Bug Summary

File:src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Transforms/Scalar/LICM.cpp
Warning:line 1229, column 33
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name LICM.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/clang/libLLVM/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Analysis -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ASMParser -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/BinaryFormat -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitcode -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitcode -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitstream -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /include/llvm/CodeGen -I /include/llvm/CodeGen/PBQP -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/IR -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IR -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Coroutines -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ProfileData/Coverage -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/CodeView -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/DWARF -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/MSF -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/PDB -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Demangle -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/JITLink -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/Orc -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend/OpenACC -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend/OpenMP -I /include/llvm/CodeGen/GlobalISel -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IRReader -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/InstCombine -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/Transforms/InstCombine -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/LTO -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Linker -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/MC -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/MC/MCParser -I /include/llvm/CodeGen/MIRParser -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Object -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Option -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Passes -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ProfileData -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Scalar -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ADT -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Support -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/Symbolize -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Target -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Utils -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Vectorize -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/IPO -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/libLLVM/../include -I /usr/src/gnu/usr.bin/clang/libLLVM/obj -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -D PIC -internal-isystem /usr/include/c++/v1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/usr/src/gnu/usr.bin/clang/libLLVM/obj -ferror-limit 19 -fvisibility-inlines-hidden -fwrapv -D_RET_PROTECTOR -ret-protector -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c++ /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Transforms/Scalar/LICM.cpp

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Transforms/Scalar/LICM.cpp

1//===-- LICM.cpp - Loop Invariant Code Motion Pass ------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This pass performs loop invariant code motion, attempting to remove as much
10// code from the body of a loop as possible. It does this by either hoisting
11// code into the preheader block, or by sinking code to the exit blocks if it is
12// safe. This pass also promotes must-aliased memory locations in the loop to
13// live in registers, thus hoisting and sinking "invariant" loads and stores.
14//
15// Hoisting operations out of loops is a canonicalization transform. It
16// enables and simplifies subsequent optimizations in the middle-end.
17// Rematerialization of hoisted instructions to reduce register pressure is the
18// responsibility of the back-end, which has more accurate information about
19// register pressure and also handles other optimizations than LICM that
20// increase live-ranges.
21//
22// This pass uses alias analysis for two purposes:
23//
24// 1. Moving loop invariant loads and calls out of loops. If we can determine
25// that a load or call inside of a loop never aliases anything stored to,
26// we can hoist it or sink it like any other instruction.
27// 2. Scalar Promotion of Memory - If there is a store instruction inside of
28// the loop, we try to move the store to happen AFTER the loop instead of
29// inside of the loop. This can only happen if a few conditions are true:
30// A. The pointer stored through is loop invariant
31// B. There are no stores or loads in the loop which _may_ alias the
32// pointer. There are no calls in the loop which mod/ref the pointer.
33// If these conditions are true, we can promote the loads and stores in the
34// loop of the pointer to use a temporary alloca'd variable. We then use
35// the SSAUpdater to construct the appropriate SSA form for the value.
36//
37//===----------------------------------------------------------------------===//
38
39#include "llvm/Transforms/Scalar/LICM.h"
40#include "llvm/ADT/SetOperations.h"
41#include "llvm/ADT/Statistic.h"
42#include "llvm/Analysis/AliasAnalysis.h"
43#include "llvm/Analysis/AliasSetTracker.h"
44#include "llvm/Analysis/BasicAliasAnalysis.h"
45#include "llvm/Analysis/BlockFrequencyInfo.h"
46#include "llvm/Analysis/CaptureTracking.h"
47#include "llvm/Analysis/ConstantFolding.h"
48#include "llvm/Analysis/GlobalsModRef.h"
49#include "llvm/Analysis/GuardUtils.h"
50#include "llvm/Analysis/LazyBlockFrequencyInfo.h"
51#include "llvm/Analysis/Loads.h"
52#include "llvm/Analysis/LoopInfo.h"
53#include "llvm/Analysis/LoopIterator.h"
54#include "llvm/Analysis/LoopPass.h"
55#include "llvm/Analysis/MemoryBuiltins.h"
56#include "llvm/Analysis/MemorySSA.h"
57#include "llvm/Analysis/MemorySSAUpdater.h"
58#include "llvm/Analysis/MustExecute.h"
59#include "llvm/Analysis/OptimizationRemarkEmitter.h"
60#include "llvm/Analysis/ScalarEvolution.h"
61#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
62#include "llvm/Analysis/TargetLibraryInfo.h"
63#include "llvm/Analysis/ValueTracking.h"
64#include "llvm/IR/CFG.h"
65#include "llvm/IR/Constants.h"
66#include "llvm/IR/DataLayout.h"
67#include "llvm/IR/DebugInfoMetadata.h"
68#include "llvm/IR/DerivedTypes.h"
69#include "llvm/IR/Dominators.h"
70#include "llvm/IR/Instructions.h"
71#include "llvm/IR/IntrinsicInst.h"
72#include "llvm/IR/LLVMContext.h"
73#include "llvm/IR/Metadata.h"
74#include "llvm/IR/PatternMatch.h"
75#include "llvm/IR/PredIteratorCache.h"
76#include "llvm/InitializePasses.h"
77#include "llvm/Support/CommandLine.h"
78#include "llvm/Support/Debug.h"
79#include "llvm/Support/raw_ostream.h"
80#include "llvm/Transforms/Scalar.h"
81#include "llvm/Transforms/Scalar/LoopPassManager.h"
82#include "llvm/Transforms/Utils/AssumeBundleBuilder.h"
83#include "llvm/Transforms/Utils/BasicBlockUtils.h"
84#include "llvm/Transforms/Utils/Local.h"
85#include "llvm/Transforms/Utils/LoopUtils.h"
86#include "llvm/Transforms/Utils/SSAUpdater.h"
87#include <algorithm>
88#include <utility>
89using namespace llvm;
90
91#define DEBUG_TYPE"licm" "licm"
92
93STATISTIC(NumCreatedBlocks, "Number of blocks created")static llvm::Statistic NumCreatedBlocks = {"licm", "NumCreatedBlocks"
, "Number of blocks created"}
;
94STATISTIC(NumClonedBranches, "Number of branches cloned")static llvm::Statistic NumClonedBranches = {"licm", "NumClonedBranches"
, "Number of branches cloned"}
;
95STATISTIC(NumSunk, "Number of instructions sunk out of loop")static llvm::Statistic NumSunk = {"licm", "NumSunk", "Number of instructions sunk out of loop"
}
;
96STATISTIC(NumHoisted, "Number of instructions hoisted out of loop")static llvm::Statistic NumHoisted = {"licm", "NumHoisted", "Number of instructions hoisted out of loop"
}
;
97STATISTIC(NumMovedLoads, "Number of load insts hoisted or sunk")static llvm::Statistic NumMovedLoads = {"licm", "NumMovedLoads"
, "Number of load insts hoisted or sunk"}
;
98STATISTIC(NumMovedCalls, "Number of call insts hoisted or sunk")static llvm::Statistic NumMovedCalls = {"licm", "NumMovedCalls"
, "Number of call insts hoisted or sunk"}
;
99STATISTIC(NumPromoted, "Number of memory locations promoted to registers")static llvm::Statistic NumPromoted = {"licm", "NumPromoted", "Number of memory locations promoted to registers"
}
;
100
101/// Memory promotion is enabled by default.
102static cl::opt<bool>
103 DisablePromotion("disable-licm-promotion", cl::Hidden, cl::init(false),
104 cl::desc("Disable memory promotion in LICM pass"));
105
106static cl::opt<bool> ControlFlowHoisting(
107 "licm-control-flow-hoisting", cl::Hidden, cl::init(false),
108 cl::desc("Enable control flow (and PHI) hoisting in LICM"));
109
110static cl::opt<unsigned> HoistSinkColdnessThreshold(
111 "licm-coldness-threshold", cl::Hidden, cl::init(4),
112 cl::desc("Relative coldness Threshold of hoisting/sinking destination "
113 "block for LICM to be considered beneficial"));
114
115static cl::opt<uint32_t> MaxNumUsesTraversed(
116 "licm-max-num-uses-traversed", cl::Hidden, cl::init(8),
117 cl::desc("Max num uses visited for identifying load "
118 "invariance in loop using invariant start (default = 8)"));
119
120// Default value of zero implies we use the regular alias set tracker mechanism
121// instead of the cross product using AA to identify aliasing of the memory
122// location we are interested in.
123static cl::opt<int>
124LICMN2Theshold("licm-n2-threshold", cl::Hidden, cl::init(0),
125 cl::desc("How many instruction to cross product using AA"));
126
127// Experimental option to allow imprecision in LICM in pathological cases, in
128// exchange for faster compile. This is to be removed if MemorySSA starts to
129// address the same issue. This flag applies only when LICM uses MemorySSA
130// instead on AliasSetTracker. LICM calls MemorySSAWalker's
131// getClobberingMemoryAccess, up to the value of the Cap, getting perfect
132// accuracy. Afterwards, LICM will call into MemorySSA's getDefiningAccess,
133// which may not be precise, since optimizeUses is capped. The result is
134// correct, but we may not get as "far up" as possible to get which access is
135// clobbering the one queried.
136cl::opt<unsigned> llvm::SetLicmMssaOptCap(
137 "licm-mssa-optimization-cap", cl::init(100), cl::Hidden,
138 cl::desc("Enable imprecision in LICM in pathological cases, in exchange "
139 "for faster compile. Caps the MemorySSA clobbering calls."));
140
141// Experimentally, memory promotion carries less importance than sinking and
142// hoisting. Limit when we do promotion when using MemorySSA, in order to save
143// compile time.
144cl::opt<unsigned> llvm::SetLicmMssaNoAccForPromotionCap(
145 "licm-mssa-max-acc-promotion", cl::init(250), cl::Hidden,
146 cl::desc("[LICM & MemorySSA] When MSSA in LICM is disabled, this has no "
147 "effect. When MSSA in LICM is enabled, then this is the maximum "
148 "number of accesses allowed to be present in a loop in order to "
149 "enable memory promotion."));
150
151static bool inSubLoop(BasicBlock *BB, Loop *CurLoop, LoopInfo *LI);
152static bool isNotUsedOrFreeInLoop(const Instruction &I, const Loop *CurLoop,
153 const LoopSafetyInfo *SafetyInfo,
154 TargetTransformInfo *TTI, bool &FreeInLoop);
155static void hoist(Instruction &I, const DominatorTree *DT, const Loop *CurLoop,
156 BasicBlock *Dest, ICFLoopSafetyInfo *SafetyInfo,
157 MemorySSAUpdater *MSSAU, ScalarEvolution *SE,
158 OptimizationRemarkEmitter *ORE);
159static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT,
160 BlockFrequencyInfo *BFI, const Loop *CurLoop,
161 ICFLoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU,
162 OptimizationRemarkEmitter *ORE);
163static bool isSafeToExecuteUnconditionally(Instruction &Inst,
164 const DominatorTree *DT,
165 const TargetLibraryInfo *TLI,
166 const Loop *CurLoop,
167 const LoopSafetyInfo *SafetyInfo,
168 OptimizationRemarkEmitter *ORE,
169 const Instruction *CtxI = nullptr);
170static bool pointerInvalidatedByLoop(MemoryLocation MemLoc,
171 AliasSetTracker *CurAST, Loop *CurLoop,
172 AAResults *AA);
173static bool pointerInvalidatedByLoopWithMSSA(MemorySSA *MSSA, MemoryUse *MU,
174 Loop *CurLoop, Instruction &I,
175 SinkAndHoistLICMFlags &Flags);
176static bool pointerInvalidatedByBlockWithMSSA(BasicBlock &BB, MemorySSA &MSSA,
177 MemoryUse &MU);
178static Instruction *cloneInstructionInExitBlock(
179 Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI,
180 const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU);
181
182static void eraseInstruction(Instruction &I, ICFLoopSafetyInfo &SafetyInfo,
183 AliasSetTracker *AST, MemorySSAUpdater *MSSAU);
184
185static void moveInstructionBefore(Instruction &I, Instruction &Dest,
186 ICFLoopSafetyInfo &SafetyInfo,
187 MemorySSAUpdater *MSSAU, ScalarEvolution *SE);
188
189static void foreachMemoryAccess(MemorySSA *MSSA, Loop *L,
190 function_ref<void(Instruction *)> Fn);
191static SmallVector<SmallSetVector<Value *, 8>, 0>
192collectPromotionCandidates(MemorySSA *MSSA, AliasAnalysis *AA, Loop *L);
193
194namespace {
195struct LoopInvariantCodeMotion {
196 bool runOnLoop(Loop *L, AAResults *AA, LoopInfo *LI, DominatorTree *DT,
197 BlockFrequencyInfo *BFI, TargetLibraryInfo *TLI,
198 TargetTransformInfo *TTI, ScalarEvolution *SE, MemorySSA *MSSA,
199 OptimizationRemarkEmitter *ORE, bool LoopNestMode = false);
200
201 LoopInvariantCodeMotion(unsigned LicmMssaOptCap,
202 unsigned LicmMssaNoAccForPromotionCap)
203 : LicmMssaOptCap(LicmMssaOptCap),
204 LicmMssaNoAccForPromotionCap(LicmMssaNoAccForPromotionCap) {}
205
206private:
207 unsigned LicmMssaOptCap;
208 unsigned LicmMssaNoAccForPromotionCap;
209
210 std::unique_ptr<AliasSetTracker>
211 collectAliasInfoForLoop(Loop *L, LoopInfo *LI, AAResults *AA);
212};
213
214struct LegacyLICMPass : public LoopPass {
215 static char ID; // Pass identification, replacement for typeid
216 LegacyLICMPass(
217 unsigned LicmMssaOptCap = SetLicmMssaOptCap,
218 unsigned LicmMssaNoAccForPromotionCap = SetLicmMssaNoAccForPromotionCap)
219 : LoopPass(ID), LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap) {
220 initializeLegacyLICMPassPass(*PassRegistry::getPassRegistry());
221 }
222
223 bool runOnLoop(Loop *L, LPPassManager &LPM) override {
224 if (skipLoop(L))
225 return false;
226
227 LLVM_DEBUG(dbgs() << "Perform LICM on Loop with header at block "do { } while (false)
228 << L->getHeader()->getNameOrAsOperand() << "\n")do { } while (false);
229
230 auto *SE = getAnalysisIfAvailable<ScalarEvolutionWrapperPass>();
231 MemorySSA *MSSA = EnableMSSALoopDependency
232 ? (&getAnalysis<MemorySSAWrapperPass>().getMSSA())
233 : nullptr;
234 bool hasProfileData = L->getHeader()->getParent()->hasProfileData();
235 BlockFrequencyInfo *BFI =
236 hasProfileData ? &getAnalysis<LazyBlockFrequencyInfoPass>().getBFI()
237 : nullptr;
238 // For the old PM, we can't use OptimizationRemarkEmitter as an analysis
239 // pass. Function analyses need to be preserved across loop transformations
240 // but ORE cannot be preserved (see comment before the pass definition).
241 OptimizationRemarkEmitter ORE(L->getHeader()->getParent());
242 return LICM.runOnLoop(
243 L, &getAnalysis<AAResultsWrapperPass>().getAAResults(),
244 &getAnalysis<LoopInfoWrapperPass>().getLoopInfo(),
245 &getAnalysis<DominatorTreeWrapperPass>().getDomTree(), BFI,
246 &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(
247 *L->getHeader()->getParent()),
248 &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(
249 *L->getHeader()->getParent()),
250 SE ? &SE->getSE() : nullptr, MSSA, &ORE);
251 }
252
253 /// This transformation requires natural loop information & requires that
254 /// loop preheaders be inserted into the CFG...
255 ///
256 void getAnalysisUsage(AnalysisUsage &AU) const override {
257 AU.addPreserved<DominatorTreeWrapperPass>();
258 AU.addPreserved<LoopInfoWrapperPass>();
259 AU.addRequired<TargetLibraryInfoWrapperPass>();
260 if (EnableMSSALoopDependency) {
261 AU.addRequired<MemorySSAWrapperPass>();
262 AU.addPreserved<MemorySSAWrapperPass>();
263 }
264 AU.addRequired<TargetTransformInfoWrapperPass>();
265 getLoopAnalysisUsage(AU);
266 LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU);
267 AU.addPreserved<LazyBlockFrequencyInfoPass>();
268 AU.addPreserved<LazyBranchProbabilityInfoPass>();
269 }
270
271private:
272 LoopInvariantCodeMotion LICM;
273};
274} // namespace
275
276PreservedAnalyses LICMPass::run(Loop &L, LoopAnalysisManager &AM,
277 LoopStandardAnalysisResults &AR, LPMUpdater &) {
278 // For the new PM, we also can't use OptimizationRemarkEmitter as an analysis
279 // pass. Function analyses need to be preserved across loop transformations
280 // but ORE cannot be preserved (see comment before the pass definition).
281 OptimizationRemarkEmitter ORE(L.getHeader()->getParent());
282
283 LoopInvariantCodeMotion LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap);
284 if (!LICM.runOnLoop(&L, &AR.AA, &AR.LI, &AR.DT, AR.BFI, &AR.TLI, &AR.TTI,
285 &AR.SE, AR.MSSA, &ORE))
286 return PreservedAnalyses::all();
287
288 auto PA = getLoopPassPreservedAnalyses();
289
290 PA.preserve<DominatorTreeAnalysis>();
291 PA.preserve<LoopAnalysis>();
292 if (AR.MSSA)
293 PA.preserve<MemorySSAAnalysis>();
294
295 return PA;
296}
297
298PreservedAnalyses LNICMPass::run(LoopNest &LN, LoopAnalysisManager &AM,
299 LoopStandardAnalysisResults &AR,
300 LPMUpdater &) {
301 // For the new PM, we also can't use OptimizationRemarkEmitter as an analysis
302 // pass. Function analyses need to be preserved across loop transformations
303 // but ORE cannot be preserved (see comment before the pass definition).
304 OptimizationRemarkEmitter ORE(LN.getParent());
305
306 LoopInvariantCodeMotion LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap);
307
308 Loop &OutermostLoop = LN.getOutermostLoop();
309 bool Changed = LICM.runOnLoop(&OutermostLoop, &AR.AA, &AR.LI, &AR.DT, AR.BFI,
310 &AR.TLI, &AR.TTI, &AR.SE, AR.MSSA, &ORE, true);
311
312 if (!Changed)
313 return PreservedAnalyses::all();
314
315 auto PA = getLoopPassPreservedAnalyses();
316
317 PA.preserve<DominatorTreeAnalysis>();
318 PA.preserve<LoopAnalysis>();
319 if (AR.MSSA)
320 PA.preserve<MemorySSAAnalysis>();
321
322 return PA;
323}
324
325char LegacyLICMPass::ID = 0;
326INITIALIZE_PASS_BEGIN(LegacyLICMPass, "licm", "Loop Invariant Code Motion",static void *initializeLegacyLICMPassPassOnce(PassRegistry &
Registry) {
327 false, false)static void *initializeLegacyLICMPassPassOnce(PassRegistry &
Registry) {
328INITIALIZE_PASS_DEPENDENCY(LoopPass)initializeLoopPassPass(Registry);
329INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)initializeTargetLibraryInfoWrapperPassPass(Registry);
330INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)initializeTargetTransformInfoWrapperPassPass(Registry);
331INITIALIZE_PASS_DEPENDENCY(MemorySSAWrapperPass)initializeMemorySSAWrapperPassPass(Registry);
332INITIALIZE_PASS_DEPENDENCY(LazyBFIPass)initializeLazyBFIPassPass(Registry);
333INITIALIZE_PASS_END(LegacyLICMPass, "licm", "Loop Invariant Code Motion", false,PassInfo *PI = new PassInfo( "Loop Invariant Code Motion", "licm"
, &LegacyLICMPass::ID, PassInfo::NormalCtor_t(callDefaultCtor
<LegacyLICMPass>), false, false); Registry.registerPass
(*PI, true); return PI; } static llvm::once_flag InitializeLegacyLICMPassPassFlag
; void llvm::initializeLegacyLICMPassPass(PassRegistry &Registry
) { llvm::call_once(InitializeLegacyLICMPassPassFlag, initializeLegacyLICMPassPassOnce
, std::ref(Registry)); }
334 false)PassInfo *PI = new PassInfo( "Loop Invariant Code Motion", "licm"
, &LegacyLICMPass::ID, PassInfo::NormalCtor_t(callDefaultCtor
<LegacyLICMPass>), false, false); Registry.registerPass
(*PI, true); return PI; } static llvm::once_flag InitializeLegacyLICMPassPassFlag
; void llvm::initializeLegacyLICMPassPass(PassRegistry &Registry
) { llvm::call_once(InitializeLegacyLICMPassPassFlag, initializeLegacyLICMPassPassOnce
, std::ref(Registry)); }
335
336Pass *llvm::createLICMPass() { return new LegacyLICMPass(); }
337Pass *llvm::createLICMPass(unsigned LicmMssaOptCap,
338 unsigned LicmMssaNoAccForPromotionCap) {
339 return new LegacyLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap);
340}
341
342llvm::SinkAndHoistLICMFlags::SinkAndHoistLICMFlags(bool IsSink, Loop *L,
343 MemorySSA *MSSA)
344 : SinkAndHoistLICMFlags(SetLicmMssaOptCap, SetLicmMssaNoAccForPromotionCap,
345 IsSink, L, MSSA) {}
346
347llvm::SinkAndHoistLICMFlags::SinkAndHoistLICMFlags(
348 unsigned LicmMssaOptCap, unsigned LicmMssaNoAccForPromotionCap, bool IsSink,
349 Loop *L, MemorySSA *MSSA)
350 : LicmMssaOptCap(LicmMssaOptCap),
351 LicmMssaNoAccForPromotionCap(LicmMssaNoAccForPromotionCap),
352 IsSink(IsSink) {
353 assert(((L != nullptr) == (MSSA != nullptr)) &&((void)0)
354 "Unexpected values for SinkAndHoistLICMFlags")((void)0);
355 if (!MSSA)
356 return;
357
358 unsigned AccessCapCount = 0;
359 for (auto *BB : L->getBlocks())
360 if (const auto *Accesses = MSSA->getBlockAccesses(BB))
361 for (const auto &MA : *Accesses) {
362 (void)MA;
363 ++AccessCapCount;
364 if (AccessCapCount > LicmMssaNoAccForPromotionCap) {
365 NoOfMemAccTooLarge = true;
366 return;
367 }
368 }
369}
370
371/// Hoist expressions out of the specified loop. Note, alias info for inner
372/// loop is not preserved so it is not a good idea to run LICM multiple
373/// times on one loop.
374bool LoopInvariantCodeMotion::runOnLoop(
375 Loop *L, AAResults *AA, LoopInfo *LI, DominatorTree *DT,
376 BlockFrequencyInfo *BFI, TargetLibraryInfo *TLI, TargetTransformInfo *TTI,
377 ScalarEvolution *SE, MemorySSA *MSSA, OptimizationRemarkEmitter *ORE,
378 bool LoopNestMode) {
379 bool Changed = false;
380
381 assert(L->isLCSSAForm(*DT) && "Loop is not in LCSSA form.")((void)0);
382
383 // If this loop has metadata indicating that LICM is not to be performed then
384 // just exit.
385 if (hasDisableLICMTransformsHint(L)) {
386 return false;
387 }
388
389 std::unique_ptr<AliasSetTracker> CurAST;
390 std::unique_ptr<MemorySSAUpdater> MSSAU;
391 std::unique_ptr<SinkAndHoistLICMFlags> Flags;
392
393 // Don't sink stores from loops with coroutine suspend instructions.
394 // LICM would sink instructions into the default destination of
395 // the coroutine switch. The default destination of the switch is to
396 // handle the case where the coroutine is suspended, by which point the
397 // coroutine frame may have been destroyed. No instruction can be sunk there.
398 // FIXME: This would unfortunately hurt the performance of coroutines, however
399 // there is currently no general solution for this. Similar issues could also
400 // potentially happen in other passes where instructions are being moved
401 // across that edge.
402 bool HasCoroSuspendInst = llvm::any_of(L->getBlocks(), [](BasicBlock *BB) {
403 return llvm::any_of(*BB, [](Instruction &I) {
404 IntrinsicInst *II = dyn_cast<IntrinsicInst>(&I);
405 return II && II->getIntrinsicID() == Intrinsic::coro_suspend;
406 });
407 });
408
409 if (!MSSA) {
410 LLVM_DEBUG(dbgs() << "LICM: Using Alias Set Tracker.\n")do { } while (false);
411 CurAST = collectAliasInfoForLoop(L, LI, AA);
412 Flags = std::make_unique<SinkAndHoistLICMFlags>(
413 LicmMssaOptCap, LicmMssaNoAccForPromotionCap, /*IsSink=*/true);
414 } else {
415 LLVM_DEBUG(dbgs() << "LICM: Using MemorySSA.\n")do { } while (false);
416 MSSAU = std::make_unique<MemorySSAUpdater>(MSSA);
417 Flags = std::make_unique<SinkAndHoistLICMFlags>(
418 LicmMssaOptCap, LicmMssaNoAccForPromotionCap, /*IsSink=*/true, L, MSSA);
419 }
420
421 // Get the preheader block to move instructions into...
422 BasicBlock *Preheader = L->getLoopPreheader();
423
424 // Compute loop safety information.
425 ICFLoopSafetyInfo SafetyInfo;
426 SafetyInfo.computeLoopSafetyInfo(L);
427
428 // We want to visit all of the instructions in this loop... that are not parts
429 // of our subloops (they have already had their invariants hoisted out of
430 // their loop, into this loop, so there is no need to process the BODIES of
431 // the subloops).
432 //
433 // Traverse the body of the loop in depth first order on the dominator tree so
434 // that we are guaranteed to see definitions before we see uses. This allows
435 // us to sink instructions in one pass, without iteration. After sinking
436 // instructions, we perform another pass to hoist them out of the loop.
437 if (L->hasDedicatedExits())
438 Changed |=
439 sinkRegion(DT->getNode(L->getHeader()), AA, LI, DT, BFI, TLI, TTI, L,
440 CurAST.get(), MSSAU.get(), &SafetyInfo, *Flags.get(), ORE);
441 Flags->setIsSink(false);
442 if (Preheader)
443 Changed |= hoistRegion(DT->getNode(L->getHeader()), AA, LI, DT, BFI, TLI, L,
444 CurAST.get(), MSSAU.get(), SE, &SafetyInfo,
445 *Flags.get(), ORE, LoopNestMode);
446
447 // Now that all loop invariants have been removed from the loop, promote any
448 // memory references to scalars that we can.
449 // Don't sink stores from loops without dedicated block exits. Exits
450 // containing indirect branches are not transformed by loop simplify,
451 // make sure we catch that. An additional load may be generated in the
452 // preheader for SSA updater, so also avoid sinking when no preheader
453 // is available.
454 if (!DisablePromotion && Preheader && L->hasDedicatedExits() &&
455 !Flags->tooManyMemoryAccesses() && !HasCoroSuspendInst) {
456 // Figure out the loop exits and their insertion points
457 SmallVector<BasicBlock *, 8> ExitBlocks;
458 L->getUniqueExitBlocks(ExitBlocks);
459
460 // We can't insert into a catchswitch.
461 bool HasCatchSwitch = llvm::any_of(ExitBlocks, [](BasicBlock *Exit) {
462 return isa<CatchSwitchInst>(Exit->getTerminator());
463 });
464
465 if (!HasCatchSwitch) {
466 SmallVector<Instruction *, 8> InsertPts;
467 SmallVector<MemoryAccess *, 8> MSSAInsertPts;
468 InsertPts.reserve(ExitBlocks.size());
469 if (MSSAU)
470 MSSAInsertPts.reserve(ExitBlocks.size());
471 for (BasicBlock *ExitBlock : ExitBlocks) {
472 InsertPts.push_back(&*ExitBlock->getFirstInsertionPt());
473 if (MSSAU)
474 MSSAInsertPts.push_back(nullptr);
475 }
476
477 PredIteratorCache PIC;
478
479 bool Promoted = false;
480 if (CurAST.get()) {
481 // Loop over all of the alias sets in the tracker object.
482 for (AliasSet &AS : *CurAST) {
483 // We can promote this alias set if it has a store, if it is a "Must"
484 // alias set, if the pointer is loop invariant, and if we are not
485 // eliminating any volatile loads or stores.
486 if (AS.isForwardingAliasSet() || !AS.isMod() || !AS.isMustAlias() ||
487 !L->isLoopInvariant(AS.begin()->getValue()))
488 continue;
489
490 assert(((void)0)
491 !AS.empty() &&((void)0)
492 "Must alias set should have at least one pointer element in it!")((void)0);
493
494 SmallSetVector<Value *, 8> PointerMustAliases;
495 for (const auto &ASI : AS)
496 PointerMustAliases.insert(ASI.getValue());
497
498 Promoted |= promoteLoopAccessesToScalars(
499 PointerMustAliases, ExitBlocks, InsertPts, MSSAInsertPts, PIC, LI,
500 DT, TLI, L, CurAST.get(), MSSAU.get(), &SafetyInfo, ORE);
501 }
502 } else {
503 // Promoting one set of accesses may make the pointers for another set
504 // loop invariant, so run this in a loop (with the MaybePromotable set
505 // decreasing in size over time).
506 bool LocalPromoted;
507 do {
508 LocalPromoted = false;
509 for (const SmallSetVector<Value *, 8> &PointerMustAliases :
510 collectPromotionCandidates(MSSA, AA, L)) {
511 LocalPromoted |= promoteLoopAccessesToScalars(
512 PointerMustAliases, ExitBlocks, InsertPts, MSSAInsertPts, PIC,
513 LI, DT, TLI, L, /*AST*/nullptr, MSSAU.get(), &SafetyInfo, ORE);
514 }
515 Promoted |= LocalPromoted;
516 } while (LocalPromoted);
517 }
518
519 // Once we have promoted values across the loop body we have to
520 // recursively reform LCSSA as any nested loop may now have values defined
521 // within the loop used in the outer loop.
522 // FIXME: This is really heavy handed. It would be a bit better to use an
523 // SSAUpdater strategy during promotion that was LCSSA aware and reformed
524 // it as it went.
525 if (Promoted)
526 formLCSSARecursively(*L, *DT, LI, SE);
527
528 Changed |= Promoted;
529 }
530 }
531
532 // Check that neither this loop nor its parent have had LCSSA broken. LICM is
533 // specifically moving instructions across the loop boundary and so it is
534 // especially in need of sanity checking here.
535 assert(L->isLCSSAForm(*DT) && "Loop not left in LCSSA form after LICM!")((void)0);
536 assert((L->isOutermost() || L->getParentLoop()->isLCSSAForm(*DT)) &&((void)0)
537 "Parent loop not left in LCSSA form after LICM!")((void)0);
538
539 if (MSSAU.get() && VerifyMemorySSA)
540 MSSAU->getMemorySSA()->verifyMemorySSA();
541
542 if (Changed && SE)
543 SE->forgetLoopDispositions(L);
544 return Changed;
545}
546
547/// Walk the specified region of the CFG (defined by all blocks dominated by
548/// the specified block, and that are in the current loop) in reverse depth
549/// first order w.r.t the DominatorTree. This allows us to visit uses before
550/// definitions, allowing us to sink a loop body in one pass without iteration.
551///
552bool llvm::sinkRegion(DomTreeNode *N, AAResults *AA, LoopInfo *LI,
553 DominatorTree *DT, BlockFrequencyInfo *BFI,
554 TargetLibraryInfo *TLI, TargetTransformInfo *TTI,
555 Loop *CurLoop, AliasSetTracker *CurAST,
556 MemorySSAUpdater *MSSAU, ICFLoopSafetyInfo *SafetyInfo,
557 SinkAndHoistLICMFlags &Flags,
558 OptimizationRemarkEmitter *ORE) {
559
560 // Verify inputs.
561 assert(N != nullptr && AA != nullptr && LI != nullptr && DT != nullptr &&((void)0)
562 CurLoop != nullptr && SafetyInfo != nullptr &&((void)0)
563 "Unexpected input to sinkRegion.")((void)0);
564 assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) &&((void)0)
565 "Either AliasSetTracker or MemorySSA should be initialized.")((void)0);
566
567 // We want to visit children before parents. We will enque all the parents
568 // before their children in the worklist and process the worklist in reverse
569 // order.
570 SmallVector<DomTreeNode *, 16> Worklist = collectChildrenInLoop(N, CurLoop);
571
572 bool Changed = false;
573 for (DomTreeNode *DTN : reverse(Worklist)) {
574 BasicBlock *BB = DTN->getBlock();
575 // Only need to process the contents of this block if it is not part of a
576 // subloop (which would already have been processed).
577 if (inSubLoop(BB, CurLoop, LI))
578 continue;
579
580 for (BasicBlock::iterator II = BB->end(); II != BB->begin();) {
581 Instruction &I = *--II;
582
583 // The instruction is not used in the loop if it is dead. In this case,
584 // we just delete it instead of sinking it.
585 if (isInstructionTriviallyDead(&I, TLI)) {
586 LLVM_DEBUG(dbgs() << "LICM deleting dead inst: " << I << '\n')do { } while (false);
587 salvageKnowledge(&I);
588 salvageDebugInfo(I);
589 ++II;
590 eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
591 Changed = true;
592 continue;
593 }
594
595 // Check to see if we can sink this instruction to the exit blocks
596 // of the loop. We can do this if the all users of the instruction are
597 // outside of the loop. In this case, it doesn't even matter if the
598 // operands of the instruction are loop invariant.
599 //
600 bool FreeInLoop = false;
601 if (!I.mayHaveSideEffects() &&
602 isNotUsedOrFreeInLoop(I, CurLoop, SafetyInfo, TTI, FreeInLoop) &&
603 canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, MSSAU, true, &Flags,
604 ORE)) {
605 if (sink(I, LI, DT, BFI, CurLoop, SafetyInfo, MSSAU, ORE)) {
606 if (!FreeInLoop) {
607 ++II;
608 salvageDebugInfo(I);
609 eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
610 }
611 Changed = true;
612 }
613 }
614 }
615 }
616 if (MSSAU && VerifyMemorySSA)
617 MSSAU->getMemorySSA()->verifyMemorySSA();
618 return Changed;
619}
620
621namespace {
622// This is a helper class for hoistRegion to make it able to hoist control flow
623// in order to be able to hoist phis. The way this works is that we initially
624// start hoisting to the loop preheader, and when we see a loop invariant branch
625// we make note of this. When we then come to hoist an instruction that's
626// conditional on such a branch we duplicate the branch and the relevant control
627// flow, then hoist the instruction into the block corresponding to its original
628// block in the duplicated control flow.
629class ControlFlowHoister {
630private:
631 // Information about the loop we are hoisting from
632 LoopInfo *LI;
633 DominatorTree *DT;
634 Loop *CurLoop;
635 MemorySSAUpdater *MSSAU;
636
637 // A map of blocks in the loop to the block their instructions will be hoisted
638 // to.
639 DenseMap<BasicBlock *, BasicBlock *> HoistDestinationMap;
640
641 // The branches that we can hoist, mapped to the block that marks a
642 // convergence point of their control flow.
643 DenseMap<BranchInst *, BasicBlock *> HoistableBranches;
644
645public:
646 ControlFlowHoister(LoopInfo *LI, DominatorTree *DT, Loop *CurLoop,
647 MemorySSAUpdater *MSSAU)
648 : LI(LI), DT(DT), CurLoop(CurLoop), MSSAU(MSSAU) {}
649
650 void registerPossiblyHoistableBranch(BranchInst *BI) {
651 // We can only hoist conditional branches with loop invariant operands.
652 if (!ControlFlowHoisting || !BI->isConditional() ||
653 !CurLoop->hasLoopInvariantOperands(BI))
654 return;
655
656 // The branch destinations need to be in the loop, and we don't gain
657 // anything by duplicating conditional branches with duplicate successors,
658 // as it's essentially the same as an unconditional branch.
659 BasicBlock *TrueDest = BI->getSuccessor(0);
660 BasicBlock *FalseDest = BI->getSuccessor(1);
661 if (!CurLoop->contains(TrueDest) || !CurLoop->contains(FalseDest) ||
662 TrueDest == FalseDest)
663 return;
664
665 // We can hoist BI if one branch destination is the successor of the other,
666 // or both have common successor which we check by seeing if the
667 // intersection of their successors is non-empty.
668 // TODO: This could be expanded to allowing branches where both ends
669 // eventually converge to a single block.
670 SmallPtrSet<BasicBlock *, 4> TrueDestSucc, FalseDestSucc;
671 TrueDestSucc.insert(succ_begin(TrueDest), succ_end(TrueDest));
672 FalseDestSucc.insert(succ_begin(FalseDest), succ_end(FalseDest));
673 BasicBlock *CommonSucc = nullptr;
674 if (TrueDestSucc.count(FalseDest)) {
675 CommonSucc = FalseDest;
676 } else if (FalseDestSucc.count(TrueDest)) {
677 CommonSucc = TrueDest;
678 } else {
679 set_intersect(TrueDestSucc, FalseDestSucc);
680 // If there's one common successor use that.
681 if (TrueDestSucc.size() == 1)
682 CommonSucc = *TrueDestSucc.begin();
683 // If there's more than one pick whichever appears first in the block list
684 // (we can't use the value returned by TrueDestSucc.begin() as it's
685 // unpredicatable which element gets returned).
686 else if (!TrueDestSucc.empty()) {
687 Function *F = TrueDest->getParent();
688 auto IsSucc = [&](BasicBlock &BB) { return TrueDestSucc.count(&BB); };
689 auto It = llvm::find_if(*F, IsSucc);
690 assert(It != F->end() && "Could not find successor in function")((void)0);
691 CommonSucc = &*It;
692 }
693 }
694 // The common successor has to be dominated by the branch, as otherwise
695 // there will be some other path to the successor that will not be
696 // controlled by this branch so any phi we hoist would be controlled by the
697 // wrong condition. This also takes care of avoiding hoisting of loop back
698 // edges.
699 // TODO: In some cases this could be relaxed if the successor is dominated
700 // by another block that's been hoisted and we can guarantee that the
701 // control flow has been replicated exactly.
702 if (CommonSucc && DT->dominates(BI, CommonSucc))
703 HoistableBranches[BI] = CommonSucc;
704 }
705
706 bool canHoistPHI(PHINode *PN) {
707 // The phi must have loop invariant operands.
708 if (!ControlFlowHoisting || !CurLoop->hasLoopInvariantOperands(PN))
709 return false;
710 // We can hoist phis if the block they are in is the target of hoistable
711 // branches which cover all of the predecessors of the block.
712 SmallPtrSet<BasicBlock *, 8> PredecessorBlocks;
713 BasicBlock *BB = PN->getParent();
714 for (BasicBlock *PredBB : predecessors(BB))
715 PredecessorBlocks.insert(PredBB);
716 // If we have less predecessor blocks than predecessors then the phi will
717 // have more than one incoming value for the same block which we can't
718 // handle.
719 // TODO: This could be handled be erasing some of the duplicate incoming
720 // values.
721 if (PredecessorBlocks.size() != pred_size(BB))
722 return false;
723 for (auto &Pair : HoistableBranches) {
724 if (Pair.second == BB) {
725 // Which blocks are predecessors via this branch depends on if the
726 // branch is triangle-like or diamond-like.
727 if (Pair.first->getSuccessor(0) == BB) {
728 PredecessorBlocks.erase(Pair.first->getParent());
729 PredecessorBlocks.erase(Pair.first->getSuccessor(1));
730 } else if (Pair.first->getSuccessor(1) == BB) {
731 PredecessorBlocks.erase(Pair.first->getParent());
732 PredecessorBlocks.erase(Pair.first->getSuccessor(0));
733 } else {
734 PredecessorBlocks.erase(Pair.first->getSuccessor(0));
735 PredecessorBlocks.erase(Pair.first->getSuccessor(1));
736 }
737 }
738 }
739 // PredecessorBlocks will now be empty if for every predecessor of BB we
740 // found a hoistable branch source.
741 return PredecessorBlocks.empty();
742 }
743
744 BasicBlock *getOrCreateHoistedBlock(BasicBlock *BB) {
745 if (!ControlFlowHoisting)
746 return CurLoop->getLoopPreheader();
747 // If BB has already been hoisted, return that
748 if (HoistDestinationMap.count(BB))
749 return HoistDestinationMap[BB];
750
751 // Check if this block is conditional based on a pending branch
752 auto HasBBAsSuccessor =
753 [&](DenseMap<BranchInst *, BasicBlock *>::value_type &Pair) {
754 return BB != Pair.second && (Pair.first->getSuccessor(0) == BB ||
755 Pair.first->getSuccessor(1) == BB);
756 };
757 auto It = llvm::find_if(HoistableBranches, HasBBAsSuccessor);
758
759 // If not involved in a pending branch, hoist to preheader
760 BasicBlock *InitialPreheader = CurLoop->getLoopPreheader();
761 if (It == HoistableBranches.end()) {
762 LLVM_DEBUG(dbgs() << "LICM using "do { } while (false)
763 << InitialPreheader->getNameOrAsOperand()do { } while (false)
764 << " as hoist destination for "do { } while (false)
765 << BB->getNameOrAsOperand() << "\n")do { } while (false);
766 HoistDestinationMap[BB] = InitialPreheader;
767 return InitialPreheader;
768 }
769 BranchInst *BI = It->first;
770 assert(std::find_if(++It, HoistableBranches.end(), HasBBAsSuccessor) ==((void)0)
771 HoistableBranches.end() &&((void)0)
772 "BB is expected to be the target of at most one branch")((void)0);
773
774 LLVMContext &C = BB->getContext();
775 BasicBlock *TrueDest = BI->getSuccessor(0);
776 BasicBlock *FalseDest = BI->getSuccessor(1);
777 BasicBlock *CommonSucc = HoistableBranches[BI];
778 BasicBlock *HoistTarget = getOrCreateHoistedBlock(BI->getParent());
779
780 // Create hoisted versions of blocks that currently don't have them
781 auto CreateHoistedBlock = [&](BasicBlock *Orig) {
782 if (HoistDestinationMap.count(Orig))
783 return HoistDestinationMap[Orig];
784 BasicBlock *New =
785 BasicBlock::Create(C, Orig->getName() + ".licm", Orig->getParent());
786 HoistDestinationMap[Orig] = New;
787 DT->addNewBlock(New, HoistTarget);
788 if (CurLoop->getParentLoop())
789 CurLoop->getParentLoop()->addBasicBlockToLoop(New, *LI);
790 ++NumCreatedBlocks;
791 LLVM_DEBUG(dbgs() << "LICM created " << New->getName()do { } while (false)
792 << " as hoist destination for " << Orig->getName()do { } while (false)
793 << "\n")do { } while (false);
794 return New;
795 };
796 BasicBlock *HoistTrueDest = CreateHoistedBlock(TrueDest);
797 BasicBlock *HoistFalseDest = CreateHoistedBlock(FalseDest);
798 BasicBlock *HoistCommonSucc = CreateHoistedBlock(CommonSucc);
799
800 // Link up these blocks with branches.
801 if (!HoistCommonSucc->getTerminator()) {
802 // The new common successor we've generated will branch to whatever that
803 // hoist target branched to.
804 BasicBlock *TargetSucc = HoistTarget->getSingleSuccessor();
805 assert(TargetSucc && "Expected hoist target to have a single successor")((void)0);
806 HoistCommonSucc->moveBefore(TargetSucc);
807 BranchInst::Create(TargetSucc, HoistCommonSucc);
808 }
809 if (!HoistTrueDest->getTerminator()) {
810 HoistTrueDest->moveBefore(HoistCommonSucc);
811 BranchInst::Create(HoistCommonSucc, HoistTrueDest);
812 }
813 if (!HoistFalseDest->getTerminator()) {
814 HoistFalseDest->moveBefore(HoistCommonSucc);
815 BranchInst::Create(HoistCommonSucc, HoistFalseDest);
816 }
817
818 // If BI is being cloned to what was originally the preheader then
819 // HoistCommonSucc will now be the new preheader.
820 if (HoistTarget == InitialPreheader) {
821 // Phis in the loop header now need to use the new preheader.
822 InitialPreheader->replaceSuccessorsPhiUsesWith(HoistCommonSucc);
823 if (MSSAU)
824 MSSAU->wireOldPredecessorsToNewImmediatePredecessor(
825 HoistTarget->getSingleSuccessor(), HoistCommonSucc, {HoistTarget});
826 // The new preheader dominates the loop header.
827 DomTreeNode *PreheaderNode = DT->getNode(HoistCommonSucc);
828 DomTreeNode *HeaderNode = DT->getNode(CurLoop->getHeader());
829 DT->changeImmediateDominator(HeaderNode, PreheaderNode);
830 // The preheader hoist destination is now the new preheader, with the
831 // exception of the hoist destination of this branch.
832 for (auto &Pair : HoistDestinationMap)
833 if (Pair.second == InitialPreheader && Pair.first != BI->getParent())
834 Pair.second = HoistCommonSucc;
835 }
836
837 // Now finally clone BI.
838 ReplaceInstWithInst(
839 HoistTarget->getTerminator(),
840 BranchInst::Create(HoistTrueDest, HoistFalseDest, BI->getCondition()));
841 ++NumClonedBranches;
842
843 assert(CurLoop->getLoopPreheader() &&((void)0)
844 "Hoisting blocks should not have destroyed preheader")((void)0);
845 return HoistDestinationMap[BB];
846 }
847};
848} // namespace
849
850// Hoisting/sinking instruction out of a loop isn't always beneficial. It's only
851// only worthwhile if the destination block is actually colder than current
852// block.
853static bool worthSinkOrHoistInst(Instruction &I, BasicBlock *DstBlock,
854 OptimizationRemarkEmitter *ORE,
855 BlockFrequencyInfo *BFI) {
856 // Check block frequency only when runtime profile is available
857 // to avoid pathological cases. With static profile, lean towards
858 // hosting because it helps canonicalize the loop for vectorizer.
859 if (!DstBlock->getParent()->hasProfileData())
860 return true;
861
862 if (!HoistSinkColdnessThreshold || !BFI)
863 return true;
864
865 BasicBlock *SrcBlock = I.getParent();
866 if (BFI->getBlockFreq(DstBlock).getFrequency() / HoistSinkColdnessThreshold >
867 BFI->getBlockFreq(SrcBlock).getFrequency()) {
868 ORE->emit([&]() {
869 return OptimizationRemarkMissed(DEBUG_TYPE"licm", "SinkHoistInst", &I)
870 << "failed to sink or hoist instruction because containing block "
871 "has lower frequency than destination block";
872 });
873 return false;
874 }
875
876 return true;
877}
878
879/// Walk the specified region of the CFG (defined by all blocks dominated by
880/// the specified block, and that are in the current loop) in depth first
881/// order w.r.t the DominatorTree. This allows us to visit definitions before
882/// uses, allowing us to hoist a loop body in one pass without iteration.
883///
884bool llvm::hoistRegion(DomTreeNode *N, AAResults *AA, LoopInfo *LI,
885 DominatorTree *DT, BlockFrequencyInfo *BFI,
886 TargetLibraryInfo *TLI, Loop *CurLoop,
887 AliasSetTracker *CurAST, MemorySSAUpdater *MSSAU,
888 ScalarEvolution *SE, ICFLoopSafetyInfo *SafetyInfo,
889 SinkAndHoistLICMFlags &Flags,
890 OptimizationRemarkEmitter *ORE, bool LoopNestMode) {
891 // Verify inputs.
892 assert(N != nullptr && AA != nullptr && LI != nullptr && DT != nullptr &&((void)0)
893 CurLoop != nullptr && SafetyInfo != nullptr &&((void)0)
894 "Unexpected input to hoistRegion.")((void)0);
895 assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) &&((void)0)
896 "Either AliasSetTracker or MemorySSA should be initialized.")((void)0);
897
898 ControlFlowHoister CFH(LI, DT, CurLoop, MSSAU);
899
900 // Keep track of instructions that have been hoisted, as they may need to be
901 // re-hoisted if they end up not dominating all of their uses.
902 SmallVector<Instruction *, 16> HoistedInstructions;
903
904 // For PHI hoisting to work we need to hoist blocks before their successors.
905 // We can do this by iterating through the blocks in the loop in reverse
906 // post-order.
907 LoopBlocksRPO Worklist(CurLoop);
908 Worklist.perform(LI);
909 bool Changed = false;
910 for (BasicBlock *BB : Worklist) {
911 // Only need to process the contents of this block if it is not part of a
912 // subloop (which would already have been processed).
913 if (!LoopNestMode && inSubLoop(BB, CurLoop, LI))
914 continue;
915
916 for (BasicBlock::iterator II = BB->begin(), E = BB->end(); II != E;) {
917 Instruction &I = *II++;
918 // Try constant folding this instruction. If all the operands are
919 // constants, it is technically hoistable, but it would be better to
920 // just fold it.
921 if (Constant *C = ConstantFoldInstruction(
922 &I, I.getModule()->getDataLayout(), TLI)) {
923 LLVM_DEBUG(dbgs() << "LICM folding inst: " << I << " --> " << *Cdo { } while (false)
924 << '\n')do { } while (false);
925 if (CurAST)
926 CurAST->copyValue(&I, C);
927 // FIXME MSSA: Such replacements may make accesses unoptimized (D51960).
928 I.replaceAllUsesWith(C);
929 if (isInstructionTriviallyDead(&I, TLI))
930 eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
931 Changed = true;
932 continue;
933 }
934
935 // Try hoisting the instruction out to the preheader. We can only do
936 // this if all of the operands of the instruction are loop invariant and
937 // if it is safe to hoist the instruction. We also check block frequency
938 // to make sure instruction only gets hoisted into colder blocks.
939 // TODO: It may be safe to hoist if we are hoisting to a conditional block
940 // and we have accurately duplicated the control flow from the loop header
941 // to that block.
942 if (CurLoop->hasLoopInvariantOperands(&I) &&
943 canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, MSSAU, true, &Flags,
944 ORE) &&
945 worthSinkOrHoistInst(I, CurLoop->getLoopPreheader(), ORE, BFI) &&
946 isSafeToExecuteUnconditionally(
947 I, DT, TLI, CurLoop, SafetyInfo, ORE,
948 CurLoop->getLoopPreheader()->getTerminator())) {
949 hoist(I, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo,
950 MSSAU, SE, ORE);
951 HoistedInstructions.push_back(&I);
952 Changed = true;
953 continue;
954 }
955
956 // Attempt to remove floating point division out of the loop by
957 // converting it to a reciprocal multiplication.
958 if (I.getOpcode() == Instruction::FDiv && I.hasAllowReciprocal() &&
959 CurLoop->isLoopInvariant(I.getOperand(1))) {
960 auto Divisor = I.getOperand(1);
961 auto One = llvm::ConstantFP::get(Divisor->getType(), 1.0);
962 auto ReciprocalDivisor = BinaryOperator::CreateFDiv(One, Divisor);
963 ReciprocalDivisor->setFastMathFlags(I.getFastMathFlags());
964 SafetyInfo->insertInstructionTo(ReciprocalDivisor, I.getParent());
965 ReciprocalDivisor->insertBefore(&I);
966
967 auto Product =
968 BinaryOperator::CreateFMul(I.getOperand(0), ReciprocalDivisor);
969 Product->setFastMathFlags(I.getFastMathFlags());
970 SafetyInfo->insertInstructionTo(Product, I.getParent());
971 Product->insertAfter(&I);
972 I.replaceAllUsesWith(Product);
973 eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
974
975 hoist(*ReciprocalDivisor, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB),
976 SafetyInfo, MSSAU, SE, ORE);
977 HoistedInstructions.push_back(ReciprocalDivisor);
978 Changed = true;
979 continue;
980 }
981
982 auto IsInvariantStart = [&](Instruction &I) {
983 using namespace PatternMatch;
984 return I.use_empty() &&
985 match(&I, m_Intrinsic<Intrinsic::invariant_start>());
986 };
987 auto MustExecuteWithoutWritesBefore = [&](Instruction &I) {
988 return SafetyInfo->isGuaranteedToExecute(I, DT, CurLoop) &&
989 SafetyInfo->doesNotWriteMemoryBefore(I, CurLoop);
990 };
991 if ((IsInvariantStart(I) || isGuard(&I)) &&
992 CurLoop->hasLoopInvariantOperands(&I) &&
993 MustExecuteWithoutWritesBefore(I)) {
994 hoist(I, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo,
995 MSSAU, SE, ORE);
996 HoistedInstructions.push_back(&I);
997 Changed = true;
998 continue;
999 }
1000
1001 if (PHINode *PN = dyn_cast<PHINode>(&I)) {
1002 if (CFH.canHoistPHI(PN)) {
1003 // Redirect incoming blocks first to ensure that we create hoisted
1004 // versions of those blocks before we hoist the phi.
1005 for (unsigned int i = 0; i < PN->getNumIncomingValues(); ++i)
1006 PN->setIncomingBlock(
1007 i, CFH.getOrCreateHoistedBlock(PN->getIncomingBlock(i)));
1008 hoist(*PN, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo,
1009 MSSAU, SE, ORE);
1010 assert(DT->dominates(PN, BB) && "Conditional PHIs not expected")((void)0);
1011 Changed = true;
1012 continue;
1013 }
1014 }
1015
1016 // Remember possibly hoistable branches so we can actually hoist them
1017 // later if needed.
1018 if (BranchInst *BI = dyn_cast<BranchInst>(&I))
1019 CFH.registerPossiblyHoistableBranch(BI);
1020 }
1021 }
1022
1023 // If we hoisted instructions to a conditional block they may not dominate
1024 // their uses that weren't hoisted (such as phis where some operands are not
1025 // loop invariant). If so make them unconditional by moving them to their
1026 // immediate dominator. We iterate through the instructions in reverse order
1027 // which ensures that when we rehoist an instruction we rehoist its operands,
1028 // and also keep track of where in the block we are rehoisting to to make sure
1029 // that we rehoist instructions before the instructions that use them.
1030 Instruction *HoistPoint = nullptr;
1031 if (ControlFlowHoisting) {
1032 for (Instruction *I : reverse(HoistedInstructions)) {
1033 if (!llvm::all_of(I->uses(),
1034 [&](Use &U) { return DT->dominates(I, U); })) {
1035 BasicBlock *Dominator =
1036 DT->getNode(I->getParent())->getIDom()->getBlock();
1037 if (!HoistPoint || !DT->dominates(HoistPoint->getParent(), Dominator)) {
1038 if (HoistPoint)
1039 assert(DT->dominates(Dominator, HoistPoint->getParent()) &&((void)0)
1040 "New hoist point expected to dominate old hoist point")((void)0);
1041 HoistPoint = Dominator->getTerminator();
1042 }
1043 LLVM_DEBUG(dbgs() << "LICM rehoisting to "do { } while (false)
1044 << HoistPoint->getParent()->getNameOrAsOperand()do { } while (false)
1045 << ": " << *I << "\n")do { } while (false);
1046 moveInstructionBefore(*I, *HoistPoint, *SafetyInfo, MSSAU, SE);
1047 HoistPoint = I;
1048 Changed = true;
1049 }
1050 }
1051 }
1052 if (MSSAU && VerifyMemorySSA)
1053 MSSAU->getMemorySSA()->verifyMemorySSA();
1054
1055 // Now that we've finished hoisting make sure that LI and DT are still
1056 // valid.
1057#ifdef EXPENSIVE_CHECKS
1058 if (Changed) {
1059 assert(DT->verify(DominatorTree::VerificationLevel::Fast) &&((void)0)
1060 "Dominator tree verification failed")((void)0);
1061 LI->verify(*DT);
1062 }
1063#endif
1064
1065 return Changed;
1066}
1067
1068// Return true if LI is invariant within scope of the loop. LI is invariant if
1069// CurLoop is dominated by an invariant.start representing the same memory
1070// location and size as the memory location LI loads from, and also the
1071// invariant.start has no uses.
1072static bool isLoadInvariantInLoop(LoadInst *LI, DominatorTree *DT,
1073 Loop *CurLoop) {
1074 Value *Addr = LI->getOperand(0);
1075 const DataLayout &DL = LI->getModule()->getDataLayout();
1076 const TypeSize LocSizeInBits = DL.getTypeSizeInBits(LI->getType());
1077
1078 // It is not currently possible for clang to generate an invariant.start
1079 // intrinsic with scalable vector types because we don't support thread local
1080 // sizeless types and we don't permit sizeless types in structs or classes.
1081 // Furthermore, even if support is added for this in future the intrinsic
1082 // itself is defined to have a size of -1 for variable sized objects. This
1083 // makes it impossible to verify if the intrinsic envelops our region of
1084 // interest. For example, both <vscale x 32 x i8> and <vscale x 16 x i8>
1085 // types would have a -1 parameter, but the former is clearly double the size
1086 // of the latter.
1087 if (LocSizeInBits.isScalable())
28
Calling 'LinearPolySize::isScalable'
30
Returning from 'LinearPolySize::isScalable'
31
Taking false branch
1088 return false;
1089
1090 // if the type is i8 addrspace(x)*, we know this is the type of
1091 // llvm.invariant.start operand
1092 auto *PtrInt8Ty = PointerType::get(Type::getInt8Ty(LI->getContext()),
1093 LI->getPointerAddressSpace());
1094 unsigned BitcastsVisited = 0;
1095 // Look through bitcasts until we reach the i8* type (this is invariant.start
1096 // operand type).
1097 while (Addr->getType() != PtrInt8Ty) {
32
Assuming the condition is true
33
Loop condition is true. Entering loop body
1098 auto *BC = dyn_cast<BitCastInst>(Addr);
34
Assuming 'Addr' is not a 'BitCastInst'
1099 // Avoid traversing high number of bitcast uses.
1100 if (++BitcastsVisited > MaxNumUsesTraversed || !BC)
35
Assuming the condition is true
1101 return false;
36
Returning zero, which participates in a condition later
1102 Addr = BC->getOperand(0);
1103 }
1104
1105 unsigned UsesVisited = 0;
1106 // Traverse all uses of the load operand value, to see if invariant.start is
1107 // one of the uses, and whether it dominates the load instruction.
1108 for (auto *U : Addr->users()) {
1109 // Avoid traversing for Load operand with high number of users.
1110 if (++UsesVisited > MaxNumUsesTraversed)
1111 return false;
1112 IntrinsicInst *II = dyn_cast<IntrinsicInst>(U);
1113 // If there are escaping uses of invariant.start instruction, the load maybe
1114 // non-invariant.
1115 if (!II || II->getIntrinsicID() != Intrinsic::invariant_start ||
1116 !II->use_empty())
1117 continue;
1118 ConstantInt *InvariantSize = cast<ConstantInt>(II->getArgOperand(0));
1119 // The intrinsic supports having a -1 argument for variable sized objects
1120 // so we should check for that here.
1121 if (InvariantSize->isNegative())
1122 continue;
1123 uint64_t InvariantSizeInBits = InvariantSize->getSExtValue() * 8;
1124 // Confirm the invariant.start location size contains the load operand size
1125 // in bits. Also, the invariant.start should dominate the load, and we
1126 // should not hoist the load out of a loop that contains this dominating
1127 // invariant.start.
1128 if (LocSizeInBits.getFixedSize() <= InvariantSizeInBits &&
1129 DT->properlyDominates(II->getParent(), CurLoop->getHeader()))
1130 return true;
1131 }
1132
1133 return false;
1134}
1135
1136namespace {
1137/// Return true if-and-only-if we know how to (mechanically) both hoist and
1138/// sink a given instruction out of a loop. Does not address legality
1139/// concerns such as aliasing or speculation safety.
1140bool isHoistableAndSinkableInst(Instruction &I) {
1141 // Only these instructions are hoistable/sinkable.
1142 return (isa<LoadInst>(I) || isa<StoreInst>(I) || isa<CallInst>(I) ||
2
Assuming 'I' is a 'LoadInst'
3
Returning the value 1, which participates in a condition later
1143 isa<FenceInst>(I) || isa<CastInst>(I) || isa<UnaryOperator>(I) ||
1144 isa<BinaryOperator>(I) || isa<SelectInst>(I) ||
1145 isa<GetElementPtrInst>(I) || isa<CmpInst>(I) ||
1146 isa<InsertElementInst>(I) || isa<ExtractElementInst>(I) ||
1147 isa<ShuffleVectorInst>(I) || isa<ExtractValueInst>(I) ||
1148 isa<InsertValueInst>(I) || isa<FreezeInst>(I));
1149}
1150/// Return true if all of the alias sets within this AST are known not to
1151/// contain a Mod, or if MSSA knows there are no MemoryDefs in the loop.
1152bool isReadOnly(AliasSetTracker *CurAST, const MemorySSAUpdater *MSSAU,
1153 const Loop *L) {
1154 if (CurAST) {
1155 for (AliasSet &AS : *CurAST) {
1156 if (!AS.isForwardingAliasSet() && AS.isMod()) {
1157 return false;
1158 }
1159 }
1160 return true;
1161 } else { /*MSSAU*/
1162 for (auto *BB : L->getBlocks())
1163 if (MSSAU->getMemorySSA()->getBlockDefs(BB))
1164 return false;
1165 return true;
1166 }
1167}
1168
1169/// Return true if I is the only Instruction with a MemoryAccess in L.
1170bool isOnlyMemoryAccess(const Instruction *I, const Loop *L,
1171 const MemorySSAUpdater *MSSAU) {
1172 for (auto *BB : L->getBlocks())
1173 if (auto *Accs = MSSAU->getMemorySSA()->getBlockAccesses(BB)) {
1174 int NotAPhi = 0;
1175 for (const auto &Acc : *Accs) {
1176 if (isa<MemoryPhi>(&Acc))
1177 continue;
1178 const auto *MUD = cast<MemoryUseOrDef>(&Acc);
1179 if (MUD->getMemoryInst() != I || NotAPhi++ == 1)
1180 return false;
1181 }
1182 }
1183 return true;
1184}
1185}
1186
1187bool llvm::canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT,
1188 Loop *CurLoop, AliasSetTracker *CurAST,
1189 MemorySSAUpdater *MSSAU,
1190 bool TargetExecutesOncePerLoop,
1191 SinkAndHoistLICMFlags *Flags,
1192 OptimizationRemarkEmitter *ORE) {
1193 assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) &&((void)0)
1194 "Either AliasSetTracker or MemorySSA should be initialized.")((void)0);
1195
1196 // If we don't understand the instruction, bail early.
1197 if (!isHoistableAndSinkableInst(I))
1
Calling 'isHoistableAndSinkableInst'
4
Returning from 'isHoistableAndSinkableInst'
5
Taking false branch
1198 return false;
1199
1200 MemorySSA *MSSA = MSSAU ? MSSAU->getMemorySSA() : nullptr;
6
Assuming 'MSSAU' is null
7
'?' condition is false
8
'MSSA' initialized to a null pointer value
1201 if (MSSA
8.1
'MSSA' is null
8.1
'MSSA' is null
8.1
'MSSA' is null
8.1
'MSSA' is null
)
9
Taking false branch
1202 assert(Flags != nullptr && "Flags cannot be null.")((void)0);
1203
1204 // Loads have extra constraints we have to verify before we can hoist them.
1205 if (LoadInst *LI
10.1
'LI' is non-null
10.1
'LI' is non-null
10.1
'LI' is non-null
10.1
'LI' is non-null
= dyn_cast<LoadInst>(&I)) {
10
Assuming the object is a 'LoadInst'
11
Taking true branch
1206 if (!LI->isUnordered())
12
Calling 'LoadInst::isUnordered'
17
Returning from 'LoadInst::isUnordered'
18
Taking false branch
1207 return false; // Don't sink/hoist volatile or ordered atomic loads!
1208
1209 // Loads from constant memory are always safe to move, even if they end up
1210 // in the same alias set as something that ends up being modified.
1211 if (AA->pointsToConstantMemory(LI->getOperand(0)))
19
Assuming the condition is false
20
Taking false branch
1212 return true;
1213 if (LI->hasMetadata(LLVMContext::MD_invariant_load))
21
Calling 'Instruction::hasMetadata'
24
Returning from 'Instruction::hasMetadata'
25
Taking false branch
1214 return true;
1215
1216 if (LI->isAtomic() && !TargetExecutesOncePerLoop)
26
Assuming the condition is false
1217 return false; // Don't risk duplicating unordered loads
1218
1219 // This checks for an invariant.start dominating the load.
1220 if (isLoadInvariantInLoop(LI, DT, CurLoop))
27
Calling 'isLoadInvariantInLoop'
37
Returning from 'isLoadInvariantInLoop'
38
Taking false branch
1221 return true;
1222
1223 bool Invalidated;
1224 if (CurAST)
39
Assuming 'CurAST' is null
40
Taking false branch
1225 Invalidated = pointerInvalidatedByLoop(MemoryLocation::get(LI), CurAST,
1226 CurLoop, AA);
1227 else
1228 Invalidated = pointerInvalidatedByLoopWithMSSA(
1229 MSSA, cast<MemoryUse>(MSSA->getMemoryAccess(LI)), CurLoop, I, *Flags);
41
Called C++ object pointer is null
1230 // Check loop-invariant address because this may also be a sinkable load
1231 // whose address is not necessarily loop-invariant.
1232 if (ORE && Invalidated && CurLoop->isLoopInvariant(LI->getPointerOperand()))
1233 ORE->emit([&]() {
1234 return OptimizationRemarkMissed(
1235 DEBUG_TYPE"licm", "LoadWithLoopInvariantAddressInvalidated", LI)
1236 << "failed to move load with loop-invariant address "
1237 "because the loop may invalidate its value";
1238 });
1239
1240 return !Invalidated;
1241 } else if (CallInst *CI = dyn_cast<CallInst>(&I)) {
1242 // Don't sink or hoist dbg info; it's legal, but not useful.
1243 if (isa<DbgInfoIntrinsic>(I))
1244 return false;
1245
1246 // Don't sink calls which can throw.
1247 if (CI->mayThrow())
1248 return false;
1249
1250 // Convergent attribute has been used on operations that involve
1251 // inter-thread communication which results are implicitly affected by the
1252 // enclosing control flows. It is not safe to hoist or sink such operations
1253 // across control flow.
1254 if (CI->isConvergent())
1255 return false;
1256
1257 using namespace PatternMatch;
1258 if (match(CI, m_Intrinsic<Intrinsic::assume>()))
1259 // Assumes don't actually alias anything or throw
1260 return true;
1261
1262 if (match(CI, m_Intrinsic<Intrinsic::experimental_widenable_condition>()))
1263 // Widenable conditions don't actually alias anything or throw
1264 return true;
1265
1266 // Handle simple cases by querying alias analysis.
1267 FunctionModRefBehavior Behavior = AA->getModRefBehavior(CI);
1268 if (Behavior == FMRB_DoesNotAccessMemory)
1269 return true;
1270 if (AAResults::onlyReadsMemory(Behavior)) {
1271 // A readonly argmemonly function only reads from memory pointed to by
1272 // it's arguments with arbitrary offsets. If we can prove there are no
1273 // writes to this memory in the loop, we can hoist or sink.
1274 if (AAResults::onlyAccessesArgPointees(Behavior)) {
1275 // TODO: expand to writeable arguments
1276 for (Value *Op : CI->arg_operands())
1277 if (Op->getType()->isPointerTy()) {
1278 bool Invalidated;
1279 if (CurAST)
1280 Invalidated = pointerInvalidatedByLoop(
1281 MemoryLocation::getBeforeOrAfter(Op), CurAST, CurLoop, AA);
1282 else
1283 Invalidated = pointerInvalidatedByLoopWithMSSA(
1284 MSSA, cast<MemoryUse>(MSSA->getMemoryAccess(CI)), CurLoop, I,
1285 *Flags);
1286 if (Invalidated)
1287 return false;
1288 }
1289 return true;
1290 }
1291
1292 // If this call only reads from memory and there are no writes to memory
1293 // in the loop, we can hoist or sink the call as appropriate.
1294 if (isReadOnly(CurAST, MSSAU, CurLoop))
1295 return true;
1296 }
1297
1298 // FIXME: This should use mod/ref information to see if we can hoist or
1299 // sink the call.
1300
1301 return false;
1302 } else if (auto *FI = dyn_cast<FenceInst>(&I)) {
1303 // Fences alias (most) everything to provide ordering. For the moment,
1304 // just give up if there are any other memory operations in the loop.
1305 if (CurAST) {
1306 auto Begin = CurAST->begin();
1307 assert(Begin != CurAST->end() && "must contain FI")((void)0);
1308 if (std::next(Begin) != CurAST->end())
1309 // constant memory for instance, TODO: handle better
1310 return false;
1311 auto *UniqueI = Begin->getUniqueInstruction();
1312 if (!UniqueI)
1313 // other memory op, give up
1314 return false;
1315 (void)FI; // suppress unused variable warning
1316 assert(UniqueI == FI && "AS must contain FI")((void)0);
1317 return true;
1318 } else // MSSAU
1319 return isOnlyMemoryAccess(FI, CurLoop, MSSAU);
1320 } else if (auto *SI = dyn_cast<StoreInst>(&I)) {
1321 if (!SI->isUnordered())
1322 return false; // Don't sink/hoist volatile or ordered atomic store!
1323
1324 // We can only hoist a store that we can prove writes a value which is not
1325 // read or overwritten within the loop. For those cases, we fallback to
1326 // load store promotion instead. TODO: We can extend this to cases where
1327 // there is exactly one write to the location and that write dominates an
1328 // arbitrary number of reads in the loop.
1329 if (CurAST) {
1330 auto &AS = CurAST->getAliasSetFor(MemoryLocation::get(SI));
1331
1332 if (AS.isRef() || !AS.isMustAlias())
1333 // Quick exit test, handled by the full path below as well.
1334 return false;
1335 auto *UniqueI = AS.getUniqueInstruction();
1336 if (!UniqueI)
1337 // other memory op, give up
1338 return false;
1339 assert(UniqueI == SI && "AS must contain SI")((void)0);
1340 return true;
1341 } else { // MSSAU
1342 if (isOnlyMemoryAccess(SI, CurLoop, MSSAU))
1343 return true;
1344 // If there are more accesses than the Promotion cap or no "quota" to
1345 // check clobber, then give up as we're not walking a list that long.
1346 if (Flags->tooManyMemoryAccesses() || Flags->tooManyClobberingCalls())
1347 return false;
1348 // If there are interfering Uses (i.e. their defining access is in the
1349 // loop), or ordered loads (stored as Defs!), don't move this store.
1350 // Could do better here, but this is conservatively correct.
1351 // TODO: Cache set of Uses on the first walk in runOnLoop, update when
1352 // moving accesses. Can also extend to dominating uses.
1353 auto *SIMD = MSSA->getMemoryAccess(SI);
1354 for (auto *BB : CurLoop->getBlocks())
1355 if (auto *Accesses = MSSA->getBlockAccesses(BB)) {
1356 for (const auto &MA : *Accesses)
1357 if (const auto *MU = dyn_cast<MemoryUse>(&MA)) {
1358 auto *MD = MU->getDefiningAccess();
1359 if (!MSSA->isLiveOnEntryDef(MD) &&
1360 CurLoop->contains(MD->getBlock()))
1361 return false;
1362 // Disable hoisting past potentially interfering loads. Optimized
1363 // Uses may point to an access outside the loop, as getClobbering
1364 // checks the previous iteration when walking the backedge.
1365 // FIXME: More precise: no Uses that alias SI.
1366 if (!Flags->getIsSink() && !MSSA->dominates(SIMD, MU))
1367 return false;
1368 } else if (const auto *MD = dyn_cast<MemoryDef>(&MA)) {
1369 if (auto *LI = dyn_cast<LoadInst>(MD->getMemoryInst())) {
1370 (void)LI; // Silence warning.
1371 assert(!LI->isUnordered() && "Expected unordered load")((void)0);
1372 return false;
1373 }
1374 // Any call, while it may not be clobbering SI, it may be a use.
1375 if (auto *CI = dyn_cast<CallInst>(MD->getMemoryInst())) {
1376 // Check if the call may read from the memory location written
1377 // to by SI. Check CI's attributes and arguments; the number of
1378 // such checks performed is limited above by NoOfMemAccTooLarge.
1379 ModRefInfo MRI = AA->getModRefInfo(CI, MemoryLocation::get(SI));
1380 if (isModOrRefSet(MRI))
1381 return false;
1382 }
1383 }
1384 }
1385 auto *Source = MSSA->getSkipSelfWalker()->getClobberingMemoryAccess(SI);
1386 Flags->incrementClobberingCalls();
1387 // If there are no clobbering Defs in the loop, store is safe to hoist.
1388 return MSSA->isLiveOnEntryDef(Source) ||
1389 !CurLoop->contains(Source->getBlock());
1390 }
1391 }
1392
1393 assert(!I.mayReadOrWriteMemory() && "unhandled aliasing")((void)0);
1394
1395 // We've established mechanical ability and aliasing, it's up to the caller
1396 // to check fault safety
1397 return true;
1398}
1399
1400/// Returns true if a PHINode is a trivially replaceable with an
1401/// Instruction.
1402/// This is true when all incoming values are that instruction.
1403/// This pattern occurs most often with LCSSA PHI nodes.
1404///
1405static bool isTriviallyReplaceablePHI(const PHINode &PN, const Instruction &I) {
1406 for (const Value *IncValue : PN.incoming_values())
1407 if (IncValue != &I)
1408 return false;
1409
1410 return true;
1411}
1412
1413/// Return true if the instruction is free in the loop.
1414static bool isFreeInLoop(const Instruction &I, const Loop *CurLoop,
1415 const TargetTransformInfo *TTI) {
1416
1417 if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&I)) {
1418 if (TTI->getUserCost(GEP, TargetTransformInfo::TCK_SizeAndLatency) !=
1419 TargetTransformInfo::TCC_Free)
1420 return false;
1421 // For a GEP, we cannot simply use getUserCost because currently it
1422 // optimistically assume that a GEP will fold into addressing mode
1423 // regardless of its users.
1424 const BasicBlock *BB = GEP->getParent();
1425 for (const User *U : GEP->users()) {
1426 const Instruction *UI = cast<Instruction>(U);
1427 if (CurLoop->contains(UI) &&
1428 (BB != UI->getParent() ||
1429 (!isa<StoreInst>(UI) && !isa<LoadInst>(UI))))
1430 return false;
1431 }
1432 return true;
1433 } else
1434 return TTI->getUserCost(&I, TargetTransformInfo::TCK_SizeAndLatency) ==
1435 TargetTransformInfo::TCC_Free;
1436}
1437
1438/// Return true if the only users of this instruction are outside of
1439/// the loop. If this is true, we can sink the instruction to the exit
1440/// blocks of the loop.
1441///
1442/// We also return true if the instruction could be folded away in lowering.
1443/// (e.g., a GEP can be folded into a load as an addressing mode in the loop).
1444static bool isNotUsedOrFreeInLoop(const Instruction &I, const Loop *CurLoop,
1445 const LoopSafetyInfo *SafetyInfo,
1446 TargetTransformInfo *TTI, bool &FreeInLoop) {
1447 const auto &BlockColors = SafetyInfo->getBlockColors();
1448 bool IsFree = isFreeInLoop(I, CurLoop, TTI);
1449 for (const User *U : I.users()) {
1450 const Instruction *UI = cast<Instruction>(U);
1451 if (const PHINode *PN = dyn_cast<PHINode>(UI)) {
1452 const BasicBlock *BB = PN->getParent();
1453 // We cannot sink uses in catchswitches.
1454 if (isa<CatchSwitchInst>(BB->getTerminator()))
1455 return false;
1456
1457 // We need to sink a callsite to a unique funclet. Avoid sinking if the
1458 // phi use is too muddled.
1459 if (isa<CallInst>(I))
1460 if (!BlockColors.empty() &&
1461 BlockColors.find(const_cast<BasicBlock *>(BB))->second.size() != 1)
1462 return false;
1463 }
1464
1465 if (CurLoop->contains(UI)) {
1466 if (IsFree) {
1467 FreeInLoop = true;
1468 continue;
1469 }
1470 return false;
1471 }
1472 }
1473 return true;
1474}
1475
1476static Instruction *cloneInstructionInExitBlock(
1477 Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI,
1478 const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU) {
1479 Instruction *New;
1480 if (auto *CI = dyn_cast<CallInst>(&I)) {
1481 const auto &BlockColors = SafetyInfo->getBlockColors();
1482
1483 // Sinking call-sites need to be handled differently from other
1484 // instructions. The cloned call-site needs a funclet bundle operand
1485 // appropriate for its location in the CFG.
1486 SmallVector<OperandBundleDef, 1> OpBundles;
1487 for (unsigned BundleIdx = 0, BundleEnd = CI->getNumOperandBundles();
1488 BundleIdx != BundleEnd; ++BundleIdx) {
1489 OperandBundleUse Bundle = CI->getOperandBundleAt(BundleIdx);
1490 if (Bundle.getTagID() == LLVMContext::OB_funclet)
1491 continue;
1492
1493 OpBundles.emplace_back(Bundle);
1494 }
1495
1496 if (!BlockColors.empty()) {
1497 const ColorVector &CV = BlockColors.find(&ExitBlock)->second;
1498 assert(CV.size() == 1 && "non-unique color for exit block!")((void)0);
1499 BasicBlock *BBColor = CV.front();
1500 Instruction *EHPad = BBColor->getFirstNonPHI();
1501 if (EHPad->isEHPad())
1502 OpBundles.emplace_back("funclet", EHPad);
1503 }
1504
1505 New = CallInst::Create(CI, OpBundles);
1506 } else {
1507 New = I.clone();
1508 }
1509
1510 ExitBlock.getInstList().insert(ExitBlock.getFirstInsertionPt(), New);
1511 if (!I.getName().empty())
1512 New->setName(I.getName() + ".le");
1513
1514 if (MSSAU && MSSAU->getMemorySSA()->getMemoryAccess(&I)) {
1515 // Create a new MemoryAccess and let MemorySSA set its defining access.
1516 MemoryAccess *NewMemAcc = MSSAU->createMemoryAccessInBB(
1517 New, nullptr, New->getParent(), MemorySSA::Beginning);
1518 if (NewMemAcc) {
1519 if (auto *MemDef = dyn_cast<MemoryDef>(NewMemAcc))
1520 MSSAU->insertDef(MemDef, /*RenameUses=*/true);
1521 else {
1522 auto *MemUse = cast<MemoryUse>(NewMemAcc);
1523 MSSAU->insertUse(MemUse, /*RenameUses=*/true);
1524 }
1525 }
1526 }
1527
1528 // Build LCSSA PHI nodes for any in-loop operands (if legal). Note that
1529 // this is particularly cheap because we can rip off the PHI node that we're
1530 // replacing for the number and blocks of the predecessors.
1531 // OPT: If this shows up in a profile, we can instead finish sinking all
1532 // invariant instructions, and then walk their operands to re-establish
1533 // LCSSA. That will eliminate creating PHI nodes just to nuke them when
1534 // sinking bottom-up.
1535 for (Use &Op : New->operands())
1536 if (LI->wouldBeOutOfLoopUseRequiringLCSSA(Op.get(), PN.getParent())) {
1537 auto *OInst = cast<Instruction>(Op.get());
1538 PHINode *OpPN =
1539 PHINode::Create(OInst->getType(), PN.getNumIncomingValues(),
1540 OInst->getName() + ".lcssa", &ExitBlock.front());
1541 for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
1542 OpPN->addIncoming(OInst, PN.getIncomingBlock(i));
1543 Op = OpPN;
1544 }
1545 return New;
1546}
1547
1548static void eraseInstruction(Instruction &I, ICFLoopSafetyInfo &SafetyInfo,
1549 AliasSetTracker *AST, MemorySSAUpdater *MSSAU) {
1550 if (AST)
1551 AST->deleteValue(&I);
1552 if (MSSAU)
1553 MSSAU->removeMemoryAccess(&I);
1554 SafetyInfo.removeInstruction(&I);
1555 I.eraseFromParent();
1556}
1557
1558static void moveInstructionBefore(Instruction &I, Instruction &Dest,
1559 ICFLoopSafetyInfo &SafetyInfo,
1560 MemorySSAUpdater *MSSAU,
1561 ScalarEvolution *SE) {
1562 SafetyInfo.removeInstruction(&I);
1563 SafetyInfo.insertInstructionTo(&I, Dest.getParent());
1564 I.moveBefore(&Dest);
1565 if (MSSAU)
1566 if (MemoryUseOrDef *OldMemAcc = cast_or_null<MemoryUseOrDef>(
1567 MSSAU->getMemorySSA()->getMemoryAccess(&I)))
1568 MSSAU->moveToPlace(OldMemAcc, Dest.getParent(),
1569 MemorySSA::BeforeTerminator);
1570 if (SE)
1571 SE->forgetValue(&I);
1572}
1573
1574static Instruction *sinkThroughTriviallyReplaceablePHI(
1575 PHINode *TPN, Instruction *I, LoopInfo *LI,
1576 SmallDenseMap<BasicBlock *, Instruction *, 32> &SunkCopies,
1577 const LoopSafetyInfo *SafetyInfo, const Loop *CurLoop,
1578 MemorySSAUpdater *MSSAU) {
1579 assert(isTriviallyReplaceablePHI(*TPN, *I) &&((void)0)
1580 "Expect only trivially replaceable PHI")((void)0);
1581 BasicBlock *ExitBlock = TPN->getParent();
1582 Instruction *New;
1583 auto It = SunkCopies.find(ExitBlock);
1584 if (It != SunkCopies.end())
1585 New = It->second;
1586 else
1587 New = SunkCopies[ExitBlock] = cloneInstructionInExitBlock(
1588 *I, *ExitBlock, *TPN, LI, SafetyInfo, MSSAU);
1589 return New;
1590}
1591
1592static bool canSplitPredecessors(PHINode *PN, LoopSafetyInfo *SafetyInfo) {
1593 BasicBlock *BB = PN->getParent();
1594 if (!BB->canSplitPredecessors())
1595 return false;
1596 // It's not impossible to split EHPad blocks, but if BlockColors already exist
1597 // it require updating BlockColors for all offspring blocks accordingly. By
1598 // skipping such corner case, we can make updating BlockColors after splitting
1599 // predecessor fairly simple.
1600 if (!SafetyInfo->getBlockColors().empty() && BB->getFirstNonPHI()->isEHPad())
1601 return false;
1602 for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
1603 BasicBlock *BBPred = *PI;
1604 if (isa<IndirectBrInst>(BBPred->getTerminator()) ||
1605 isa<CallBrInst>(BBPred->getTerminator()))
1606 return false;
1607 }
1608 return true;
1609}
1610
1611static void splitPredecessorsOfLoopExit(PHINode *PN, DominatorTree *DT,
1612 LoopInfo *LI, const Loop *CurLoop,
1613 LoopSafetyInfo *SafetyInfo,
1614 MemorySSAUpdater *MSSAU) {
1615#ifndef NDEBUG1
1616 SmallVector<BasicBlock *, 32> ExitBlocks;
1617 CurLoop->getUniqueExitBlocks(ExitBlocks);
1618 SmallPtrSet<BasicBlock *, 32> ExitBlockSet(ExitBlocks.begin(),
1619 ExitBlocks.end());
1620#endif
1621 BasicBlock *ExitBB = PN->getParent();
1622 assert(ExitBlockSet.count(ExitBB) && "Expect the PHI is in an exit block.")((void)0);
1623
1624 // Split predecessors of the loop exit to make instructions in the loop are
1625 // exposed to exit blocks through trivially replaceable PHIs while keeping the
1626 // loop in the canonical form where each predecessor of each exit block should
1627 // be contained within the loop. For example, this will convert the loop below
1628 // from
1629 //
1630 // LB1:
1631 // %v1 =
1632 // br %LE, %LB2
1633 // LB2:
1634 // %v2 =
1635 // br %LE, %LB1
1636 // LE:
1637 // %p = phi [%v1, %LB1], [%v2, %LB2] <-- non-trivially replaceable
1638 //
1639 // to
1640 //
1641 // LB1:
1642 // %v1 =
1643 // br %LE.split, %LB2
1644 // LB2:
1645 // %v2 =
1646 // br %LE.split2, %LB1
1647 // LE.split:
1648 // %p1 = phi [%v1, %LB1] <-- trivially replaceable
1649 // br %LE
1650 // LE.split2:
1651 // %p2 = phi [%v2, %LB2] <-- trivially replaceable
1652 // br %LE
1653 // LE:
1654 // %p = phi [%p1, %LE.split], [%p2, %LE.split2]
1655 //
1656 const auto &BlockColors = SafetyInfo->getBlockColors();
1657 SmallSetVector<BasicBlock *, 8> PredBBs(pred_begin(ExitBB), pred_end(ExitBB));
1658 while (!PredBBs.empty()) {
1659 BasicBlock *PredBB = *PredBBs.begin();
1660 assert(CurLoop->contains(PredBB) &&((void)0)
1661 "Expect all predecessors are in the loop")((void)0);
1662 if (PN->getBasicBlockIndex(PredBB) >= 0) {
1663 BasicBlock *NewPred = SplitBlockPredecessors(
1664 ExitBB, PredBB, ".split.loop.exit", DT, LI, MSSAU, true);
1665 // Since we do not allow splitting EH-block with BlockColors in
1666 // canSplitPredecessors(), we can simply assign predecessor's color to
1667 // the new block.
1668 if (!BlockColors.empty())
1669 // Grab a reference to the ColorVector to be inserted before getting the
1670 // reference to the vector we are copying because inserting the new
1671 // element in BlockColors might cause the map to be reallocated.
1672 SafetyInfo->copyColors(NewPred, PredBB);
1673 }
1674 PredBBs.remove(PredBB);
1675 }
1676}
1677
1678/// When an instruction is found to only be used outside of the loop, this
1679/// function moves it to the exit blocks and patches up SSA form as needed.
1680/// This method is guaranteed to remove the original instruction from its
1681/// position, and may either delete it or move it to outside of the loop.
1682///
1683static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT,
1684 BlockFrequencyInfo *BFI, const Loop *CurLoop,
1685 ICFLoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU,
1686 OptimizationRemarkEmitter *ORE) {
1687 bool Changed = false;
1688 LLVM_DEBUG(dbgs() << "LICM sinking instruction: " << I << "\n")do { } while (false);
1689
1690 // Iterate over users to be ready for actual sinking. Replace users via
1691 // unreachable blocks with undef and make all user PHIs trivially replaceable.
1692 SmallPtrSet<Instruction *, 8> VisitedUsers;
1693 for (Value::user_iterator UI = I.user_begin(), UE = I.user_end(); UI != UE;) {
1694 auto *User = cast<Instruction>(*UI);
1695 Use &U = UI.getUse();
1696 ++UI;
1697
1698 if (VisitedUsers.count(User) || CurLoop->contains(User))
1699 continue;
1700
1701 if (!DT->isReachableFromEntry(User->getParent())) {
1702 U = UndefValue::get(I.getType());
1703 Changed = true;
1704 continue;
1705 }
1706
1707 // The user must be a PHI node.
1708 PHINode *PN = cast<PHINode>(User);
1709
1710 // Surprisingly, instructions can be used outside of loops without any
1711 // exits. This can only happen in PHI nodes if the incoming block is
1712 // unreachable.
1713 BasicBlock *BB = PN->getIncomingBlock(U);
1714 if (!DT->isReachableFromEntry(BB)) {
1715 U = UndefValue::get(I.getType());
1716 Changed = true;
1717 continue;
1718 }
1719
1720 VisitedUsers.insert(PN);
1721 if (isTriviallyReplaceablePHI(*PN, I))
1722 continue;
1723
1724 if (!canSplitPredecessors(PN, SafetyInfo))
1725 return Changed;
1726
1727 // Split predecessors of the PHI so that we can make users trivially
1728 // replaceable.
1729 splitPredecessorsOfLoopExit(PN, DT, LI, CurLoop, SafetyInfo, MSSAU);
1730
1731 // Should rebuild the iterators, as they may be invalidated by
1732 // splitPredecessorsOfLoopExit().
1733 UI = I.user_begin();
1734 UE = I.user_end();
1735 }
1736
1737 if (VisitedUsers.empty())
1738 return Changed;
1739
1740 ORE->emit([&]() {
1741 return OptimizationRemark(DEBUG_TYPE"licm", "InstSunk", &I)
1742 << "sinking " << ore::NV("Inst", &I);
1743 });
1744 if (isa<LoadInst>(I))
1745 ++NumMovedLoads;
1746 else if (isa<CallInst>(I))
1747 ++NumMovedCalls;
1748 ++NumSunk;
1749
1750#ifndef NDEBUG1
1751 SmallVector<BasicBlock *, 32> ExitBlocks;
1752 CurLoop->getUniqueExitBlocks(ExitBlocks);
1753 SmallPtrSet<BasicBlock *, 32> ExitBlockSet(ExitBlocks.begin(),
1754 ExitBlocks.end());
1755#endif
1756
1757 // Clones of this instruction. Don't create more than one per exit block!
1758 SmallDenseMap<BasicBlock *, Instruction *, 32> SunkCopies;
1759
1760 // If this instruction is only used outside of the loop, then all users are
1761 // PHI nodes in exit blocks due to LCSSA form. Just RAUW them with clones of
1762 // the instruction.
1763 // First check if I is worth sinking for all uses. Sink only when it is worth
1764 // across all uses.
1765 SmallSetVector<User*, 8> Users(I.user_begin(), I.user_end());
1766 SmallVector<PHINode *, 8> ExitPNs;
1767 for (auto *UI : Users) {
1768 auto *User = cast<Instruction>(UI);
1769
1770 if (CurLoop->contains(User))
1771 continue;
1772
1773 PHINode *PN = cast<PHINode>(User);
1774 assert(ExitBlockSet.count(PN->getParent()) &&((void)0)
1775 "The LCSSA PHI is not in an exit block!")((void)0);
1776 if (!worthSinkOrHoistInst(I, PN->getParent(), ORE, BFI)) {
1777 return Changed;
1778 }
1779
1780 ExitPNs.push_back(PN);
1781 }
1782
1783 for (auto *PN : ExitPNs) {
1784
1785 // The PHI must be trivially replaceable.
1786 Instruction *New = sinkThroughTriviallyReplaceablePHI(
1787 PN, &I, LI, SunkCopies, SafetyInfo, CurLoop, MSSAU);
1788 PN->replaceAllUsesWith(New);
1789 eraseInstruction(*PN, *SafetyInfo, nullptr, nullptr);
1790 Changed = true;
1791 }
1792 return Changed;
1793}
1794
1795/// When an instruction is found to only use loop invariant operands that
1796/// is safe to hoist, this instruction is called to do the dirty work.
1797///
1798static void hoist(Instruction &I, const DominatorTree *DT, const Loop *CurLoop,
1799 BasicBlock *Dest, ICFLoopSafetyInfo *SafetyInfo,
1800 MemorySSAUpdater *MSSAU, ScalarEvolution *SE,
1801 OptimizationRemarkEmitter *ORE) {
1802 LLVM_DEBUG(dbgs() << "LICM hoisting to " << Dest->getNameOrAsOperand() << ": "do { } while (false)
1803 << I << "\n")do { } while (false);
1804 ORE->emit([&]() {
1805 return OptimizationRemark(DEBUG_TYPE"licm", "Hoisted", &I) << "hoisting "
1806 << ore::NV("Inst", &I);
1807 });
1808
1809 // Metadata can be dependent on conditions we are hoisting above.
1810 // Conservatively strip all metadata on the instruction unless we were
1811 // guaranteed to execute I if we entered the loop, in which case the metadata
1812 // is valid in the loop preheader.
1813 // Similarly, If I is a call and it is not guaranteed to execute in the loop,
1814 // then moving to the preheader means we should strip attributes on the call
1815 // that can cause UB since we may be hoisting above conditions that allowed
1816 // inferring those attributes. They may not be valid at the preheader.
1817 if ((I.hasMetadataOtherThanDebugLoc() || isa<CallInst>(I)) &&
1818 // The check on hasMetadataOtherThanDebugLoc is to prevent us from burning
1819 // time in isGuaranteedToExecute if we don't actually have anything to
1820 // drop. It is a compile time optimization, not required for correctness.
1821 !SafetyInfo->isGuaranteedToExecute(I, DT, CurLoop))
1822 I.dropUndefImplyingAttrsAndUnknownMetadata();
1823
1824 if (isa<PHINode>(I))
1825 // Move the new node to the end of the phi list in the destination block.
1826 moveInstructionBefore(I, *Dest->getFirstNonPHI(), *SafetyInfo, MSSAU, SE);
1827 else
1828 // Move the new node to the destination block, before its terminator.
1829 moveInstructionBefore(I, *Dest->getTerminator(), *SafetyInfo, MSSAU, SE);
1830
1831 I.updateLocationAfterHoist();
1832
1833 if (isa<LoadInst>(I))
1834 ++NumMovedLoads;
1835 else if (isa<CallInst>(I))
1836 ++NumMovedCalls;
1837 ++NumHoisted;
1838}
1839
1840/// Only sink or hoist an instruction if it is not a trapping instruction,
1841/// or if the instruction is known not to trap when moved to the preheader.
1842/// or if it is a trapping instruction and is guaranteed to execute.
1843static bool isSafeToExecuteUnconditionally(Instruction &Inst,
1844 const DominatorTree *DT,
1845 const TargetLibraryInfo *TLI,
1846 const Loop *CurLoop,
1847 const LoopSafetyInfo *SafetyInfo,
1848 OptimizationRemarkEmitter *ORE,
1849 const Instruction *CtxI) {
1850 if (isSafeToSpeculativelyExecute(&Inst, CtxI, DT, TLI))
1851 return true;
1852
1853 bool GuaranteedToExecute =
1854 SafetyInfo->isGuaranteedToExecute(Inst, DT, CurLoop);
1855
1856 if (!GuaranteedToExecute) {
1857 auto *LI = dyn_cast<LoadInst>(&Inst);
1858 if (LI && CurLoop->isLoopInvariant(LI->getPointerOperand()))
1859 ORE->emit([&]() {
1860 return OptimizationRemarkMissed(
1861 DEBUG_TYPE"licm", "LoadWithLoopInvariantAddressCondExecuted", LI)
1862 << "failed to hoist load with loop-invariant address "
1863 "because load is conditionally executed";
1864 });
1865 }
1866
1867 return GuaranteedToExecute;
1868}
1869
1870namespace {
1871class LoopPromoter : public LoadAndStorePromoter {
1872 Value *SomePtr; // Designated pointer to store to.
1873 const SmallSetVector<Value *, 8> &PointerMustAliases;
1874 SmallVectorImpl<BasicBlock *> &LoopExitBlocks;
1875 SmallVectorImpl<Instruction *> &LoopInsertPts;
1876 SmallVectorImpl<MemoryAccess *> &MSSAInsertPts;
1877 PredIteratorCache &PredCache;
1878 AliasSetTracker *AST;
1879 MemorySSAUpdater *MSSAU;
1880 LoopInfo &LI;
1881 DebugLoc DL;
1882 int Alignment;
1883 bool UnorderedAtomic;
1884 AAMDNodes AATags;
1885 ICFLoopSafetyInfo &SafetyInfo;
1886
1887 // We're about to add a use of V in a loop exit block. Insert an LCSSA phi
1888 // (if legal) if doing so would add an out-of-loop use to an instruction
1889 // defined in-loop.
1890 Value *maybeInsertLCSSAPHI(Value *V, BasicBlock *BB) const {
1891 if (!LI.wouldBeOutOfLoopUseRequiringLCSSA(V, BB))
1892 return V;
1893
1894 Instruction *I = cast<Instruction>(V);
1895 // We need to create an LCSSA PHI node for the incoming value and
1896 // store that.
1897 PHINode *PN = PHINode::Create(I->getType(), PredCache.size(BB),
1898 I->getName() + ".lcssa", &BB->front());
1899 for (BasicBlock *Pred : PredCache.get(BB))
1900 PN->addIncoming(I, Pred);
1901 return PN;
1902 }
1903
1904public:
1905 LoopPromoter(Value *SP, ArrayRef<const Instruction *> Insts, SSAUpdater &S,
1906 const SmallSetVector<Value *, 8> &PMA,
1907 SmallVectorImpl<BasicBlock *> &LEB,
1908 SmallVectorImpl<Instruction *> &LIP,
1909 SmallVectorImpl<MemoryAccess *> &MSSAIP, PredIteratorCache &PIC,
1910 AliasSetTracker *ast, MemorySSAUpdater *MSSAU, LoopInfo &li,
1911 DebugLoc dl, int alignment, bool UnorderedAtomic,
1912 const AAMDNodes &AATags, ICFLoopSafetyInfo &SafetyInfo)
1913 : LoadAndStorePromoter(Insts, S), SomePtr(SP), PointerMustAliases(PMA),
1914 LoopExitBlocks(LEB), LoopInsertPts(LIP), MSSAInsertPts(MSSAIP),
1915 PredCache(PIC), AST(ast), MSSAU(MSSAU), LI(li), DL(std::move(dl)),
1916 Alignment(alignment), UnorderedAtomic(UnorderedAtomic), AATags(AATags),
1917 SafetyInfo(SafetyInfo) {}
1918
1919 bool isInstInList(Instruction *I,
1920 const SmallVectorImpl<Instruction *> &) const override {
1921 Value *Ptr;
1922 if (LoadInst *LI = dyn_cast<LoadInst>(I))
1923 Ptr = LI->getOperand(0);
1924 else
1925 Ptr = cast<StoreInst>(I)->getPointerOperand();
1926 return PointerMustAliases.count(Ptr);
1927 }
1928
1929 void doExtraRewritesBeforeFinalDeletion() override {
1930 // Insert stores after in the loop exit blocks. Each exit block gets a
1931 // store of the live-out values that feed them. Since we've already told
1932 // the SSA updater about the defs in the loop and the preheader
1933 // definition, it is all set and we can start using it.
1934 for (unsigned i = 0, e = LoopExitBlocks.size(); i != e; ++i) {
1935 BasicBlock *ExitBlock = LoopExitBlocks[i];
1936 Value *LiveInValue = SSA.GetValueInMiddleOfBlock(ExitBlock);
1937 LiveInValue = maybeInsertLCSSAPHI(LiveInValue, ExitBlock);
1938 Value *Ptr = maybeInsertLCSSAPHI(SomePtr, ExitBlock);
1939 Instruction *InsertPos = LoopInsertPts[i];
1940 StoreInst *NewSI = new StoreInst(LiveInValue, Ptr, InsertPos);
1941 if (UnorderedAtomic)
1942 NewSI->setOrdering(AtomicOrdering::Unordered);
1943 NewSI->setAlignment(Align(Alignment));
1944 NewSI->setDebugLoc(DL);
1945 if (AATags)
1946 NewSI->setAAMetadata(AATags);
1947
1948 if (MSSAU) {
1949 MemoryAccess *MSSAInsertPoint = MSSAInsertPts[i];
1950 MemoryAccess *NewMemAcc;
1951 if (!MSSAInsertPoint) {
1952 NewMemAcc = MSSAU->createMemoryAccessInBB(
1953 NewSI, nullptr, NewSI->getParent(), MemorySSA::Beginning);
1954 } else {
1955 NewMemAcc =
1956 MSSAU->createMemoryAccessAfter(NewSI, nullptr, MSSAInsertPoint);
1957 }
1958 MSSAInsertPts[i] = NewMemAcc;
1959 MSSAU->insertDef(cast<MemoryDef>(NewMemAcc), true);
1960 // FIXME: true for safety, false may still be correct.
1961 }
1962 }
1963 }
1964
1965 void replaceLoadWithValue(LoadInst *LI, Value *V) const override {
1966 // Update alias analysis.
1967 if (AST)
1968 AST->copyValue(LI, V);
1969 }
1970 void instructionDeleted(Instruction *I) const override {
1971 SafetyInfo.removeInstruction(I);
1972 if (AST)
1973 AST->deleteValue(I);
1974 if (MSSAU)
1975 MSSAU->removeMemoryAccess(I);
1976 }
1977};
1978
1979bool isNotCapturedBeforeOrInLoop(const Value *V, const Loop *L,
1980 DominatorTree *DT) {
1981 // We can perform the captured-before check against any instruction in the
1982 // loop header, as the loop header is reachable from any instruction inside
1983 // the loop.
1984 // TODO: ReturnCaptures=true shouldn't be necessary here.
1985 return !PointerMayBeCapturedBefore(V, /* ReturnCaptures */ true,
1986 /* StoreCaptures */ true,
1987 L->getHeader()->getTerminator(), DT);
1988}
1989
1990/// Return true iff we can prove that a caller of this function can not inspect
1991/// the contents of the provided object in a well defined program.
1992bool isKnownNonEscaping(Value *Object, const Loop *L,
1993 const TargetLibraryInfo *TLI, DominatorTree *DT) {
1994 if (isa<AllocaInst>(Object))
1995 // Since the alloca goes out of scope, we know the caller can't retain a
1996 // reference to it and be well defined. Thus, we don't need to check for
1997 // capture.
1998 return true;
1999
2000 // For all other objects we need to know that the caller can't possibly
2001 // have gotten a reference to the object. There are two components of
2002 // that:
2003 // 1) Object can't be escaped by this function. This is what
2004 // PointerMayBeCaptured checks.
2005 // 2) Object can't have been captured at definition site. For this, we
2006 // need to know the return value is noalias. At the moment, we use a
2007 // weaker condition and handle only AllocLikeFunctions (which are
2008 // known to be noalias). TODO
2009 return isAllocLikeFn(Object, TLI) &&
2010 isNotCapturedBeforeOrInLoop(Object, L, DT);
2011}
2012
2013} // namespace
2014
2015/// Try to promote memory values to scalars by sinking stores out of the
2016/// loop and moving loads to before the loop. We do this by looping over
2017/// the stores in the loop, looking for stores to Must pointers which are
2018/// loop invariant.
2019///
2020bool llvm::promoteLoopAccessesToScalars(
2021 const SmallSetVector<Value *, 8> &PointerMustAliases,
2022 SmallVectorImpl<BasicBlock *> &ExitBlocks,
2023 SmallVectorImpl<Instruction *> &InsertPts,
2024 SmallVectorImpl<MemoryAccess *> &MSSAInsertPts, PredIteratorCache &PIC,
2025 LoopInfo *LI, DominatorTree *DT, const TargetLibraryInfo *TLI,
2026 Loop *CurLoop, AliasSetTracker *CurAST, MemorySSAUpdater *MSSAU,
2027 ICFLoopSafetyInfo *SafetyInfo, OptimizationRemarkEmitter *ORE) {
2028 // Verify inputs.
2029 assert(LI != nullptr && DT != nullptr && CurLoop != nullptr &&((void)0)
2030 SafetyInfo != nullptr &&((void)0)
2031 "Unexpected Input to promoteLoopAccessesToScalars")((void)0);
2032
2033 Value *SomePtr = *PointerMustAliases.begin();
2034 BasicBlock *Preheader = CurLoop->getLoopPreheader();
2035
2036 // It is not safe to promote a load/store from the loop if the load/store is
2037 // conditional. For example, turning:
2038 //
2039 // for () { if (c) *P += 1; }
2040 //
2041 // into:
2042 //
2043 // tmp = *P; for () { if (c) tmp +=1; } *P = tmp;
2044 //
2045 // is not safe, because *P may only be valid to access if 'c' is true.
2046 //
2047 // The safety property divides into two parts:
2048 // p1) The memory may not be dereferenceable on entry to the loop. In this
2049 // case, we can't insert the required load in the preheader.
2050 // p2) The memory model does not allow us to insert a store along any dynamic
2051 // path which did not originally have one.
2052 //
2053 // If at least one store is guaranteed to execute, both properties are
2054 // satisfied, and promotion is legal.
2055 //
2056 // This, however, is not a necessary condition. Even if no store/load is
2057 // guaranteed to execute, we can still establish these properties.
2058 // We can establish (p1) by proving that hoisting the load into the preheader
2059 // is safe (i.e. proving dereferenceability on all paths through the loop). We
2060 // can use any access within the alias set to prove dereferenceability,
2061 // since they're all must alias.
2062 //
2063 // There are two ways establish (p2):
2064 // a) Prove the location is thread-local. In this case the memory model
2065 // requirement does not apply, and stores are safe to insert.
2066 // b) Prove a store dominates every exit block. In this case, if an exit
2067 // blocks is reached, the original dynamic path would have taken us through
2068 // the store, so inserting a store into the exit block is safe. Note that this
2069 // is different from the store being guaranteed to execute. For instance,
2070 // if an exception is thrown on the first iteration of the loop, the original
2071 // store is never executed, but the exit blocks are not executed either.
2072
2073 bool DereferenceableInPH = false;
2074 bool SafeToInsertStore = false;
2075
2076 SmallVector<Instruction *, 64> LoopUses;
2077
2078 // We start with an alignment of one and try to find instructions that allow
2079 // us to prove better alignment.
2080 Align Alignment;
2081 // Keep track of which types of access we see
2082 bool SawUnorderedAtomic = false;
2083 bool SawNotAtomic = false;
2084 AAMDNodes AATags;
2085
2086 const DataLayout &MDL = Preheader->getModule()->getDataLayout();
2087
2088 bool IsKnownThreadLocalObject = false;
2089 if (SafetyInfo->anyBlockMayThrow()) {
2090 // If a loop can throw, we have to insert a store along each unwind edge.
2091 // That said, we can't actually make the unwind edge explicit. Therefore,
2092 // we have to prove that the store is dead along the unwind edge. We do
2093 // this by proving that the caller can't have a reference to the object
2094 // after return and thus can't possibly load from the object.
2095 Value *Object = getUnderlyingObject(SomePtr);
2096 if (!isKnownNonEscaping(Object, CurLoop, TLI, DT))
2097 return false;
2098 // Subtlety: Alloca's aren't visible to callers, but *are* potentially
2099 // visible to other threads if captured and used during their lifetimes.
2100 IsKnownThreadLocalObject = !isa<AllocaInst>(Object);
2101 }
2102
2103 // Check that all of the pointers in the alias set have the same type. We
2104 // cannot (yet) promote a memory location that is loaded and stored in
2105 // different sizes. While we are at it, collect alignment and AA info.
2106 for (Value *ASIV : PointerMustAliases) {
2107 // Check that all of the pointers in the alias set have the same type. We
2108 // cannot (yet) promote a memory location that is loaded and stored in
2109 // different sizes.
2110 if (SomePtr->getType() != ASIV->getType())
2111 return false;
2112
2113 for (User *U : ASIV->users()) {
2114 // Ignore instructions that are outside the loop.
2115 Instruction *UI = dyn_cast<Instruction>(U);
2116 if (!UI || !CurLoop->contains(UI))
2117 continue;
2118
2119 // If there is an non-load/store instruction in the loop, we can't promote
2120 // it.
2121 if (LoadInst *Load = dyn_cast<LoadInst>(UI)) {
2122 if (!Load->isUnordered())
2123 return false;
2124
2125 SawUnorderedAtomic |= Load->isAtomic();
2126 SawNotAtomic |= !Load->isAtomic();
2127
2128 Align InstAlignment = Load->getAlign();
2129
2130 // Note that proving a load safe to speculate requires proving
2131 // sufficient alignment at the target location. Proving it guaranteed
2132 // to execute does as well. Thus we can increase our guaranteed
2133 // alignment as well.
2134 if (!DereferenceableInPH || (InstAlignment > Alignment))
2135 if (isSafeToExecuteUnconditionally(*Load, DT, TLI, CurLoop,
2136 SafetyInfo, ORE,
2137 Preheader->getTerminator())) {
2138 DereferenceableInPH = true;
2139 Alignment = std::max(Alignment, InstAlignment);
2140 }
2141 } else if (const StoreInst *Store = dyn_cast<StoreInst>(UI)) {
2142 // Stores *of* the pointer are not interesting, only stores *to* the
2143 // pointer.
2144 if (UI->getOperand(1) != ASIV)
2145 continue;
2146 if (!Store->isUnordered())
2147 return false;
2148
2149 SawUnorderedAtomic |= Store->isAtomic();
2150 SawNotAtomic |= !Store->isAtomic();
2151
2152 // If the store is guaranteed to execute, both properties are satisfied.
2153 // We may want to check if a store is guaranteed to execute even if we
2154 // already know that promotion is safe, since it may have higher
2155 // alignment than any other guaranteed stores, in which case we can
2156 // raise the alignment on the promoted store.
2157 Align InstAlignment = Store->getAlign();
2158
2159 if (!DereferenceableInPH || !SafeToInsertStore ||
2160 (InstAlignment > Alignment)) {
2161 if (SafetyInfo->isGuaranteedToExecute(*UI, DT, CurLoop)) {
2162 DereferenceableInPH = true;
2163 SafeToInsertStore = true;
2164 Alignment = std::max(Alignment, InstAlignment);
2165 }
2166 }
2167
2168 // If a store dominates all exit blocks, it is safe to sink.
2169 // As explained above, if an exit block was executed, a dominating
2170 // store must have been executed at least once, so we are not
2171 // introducing stores on paths that did not have them.
2172 // Note that this only looks at explicit exit blocks. If we ever
2173 // start sinking stores into unwind edges (see above), this will break.
2174 if (!SafeToInsertStore)
2175 SafeToInsertStore = llvm::all_of(ExitBlocks, [&](BasicBlock *Exit) {
2176 return DT->dominates(Store->getParent(), Exit);
2177 });
2178
2179 // If the store is not guaranteed to execute, we may still get
2180 // deref info through it.
2181 if (!DereferenceableInPH) {
2182 DereferenceableInPH = isDereferenceableAndAlignedPointer(
2183 Store->getPointerOperand(), Store->getValueOperand()->getType(),
2184 Store->getAlign(), MDL, Preheader->getTerminator(), DT, TLI);
2185 }
2186 } else
2187 return false; // Not a load or store.
2188
2189 // Merge the AA tags.
2190 if (LoopUses.empty()) {
2191 // On the first load/store, just take its AA tags.
2192 UI->getAAMetadata(AATags);
2193 } else if (AATags) {
2194 UI->getAAMetadata(AATags, /* Merge = */ true);
2195 }
2196
2197 LoopUses.push_back(UI);
2198 }
2199 }
2200
2201 // If we found both an unordered atomic instruction and a non-atomic memory
2202 // access, bail. We can't blindly promote non-atomic to atomic since we
2203 // might not be able to lower the result. We can't downgrade since that
2204 // would violate memory model. Also, align 0 is an error for atomics.
2205 if (SawUnorderedAtomic && SawNotAtomic)
2206 return false;
2207
2208 // If we're inserting an atomic load in the preheader, we must be able to
2209 // lower it. We're only guaranteed to be able to lower naturally aligned
2210 // atomics.
2211 auto *SomePtrElemType = SomePtr->getType()->getPointerElementType();
2212 if (SawUnorderedAtomic &&
2213 Alignment < MDL.getTypeStoreSize(SomePtrElemType))
2214 return false;
2215
2216 // If we couldn't prove we can hoist the load, bail.
2217 if (!DereferenceableInPH)
2218 return false;
2219
2220 // We know we can hoist the load, but don't have a guaranteed store.
2221 // Check whether the location is thread-local. If it is, then we can insert
2222 // stores along paths which originally didn't have them without violating the
2223 // memory model.
2224 if (!SafeToInsertStore) {
2225 if (IsKnownThreadLocalObject)
2226 SafeToInsertStore = true;
2227 else {
2228 Value *Object = getUnderlyingObject(SomePtr);
2229 SafeToInsertStore =
2230 (isAllocLikeFn(Object, TLI) || isa<AllocaInst>(Object)) &&
2231 isNotCapturedBeforeOrInLoop(Object, CurLoop, DT);
2232 }
2233 }
2234
2235 // If we've still failed to prove we can sink the store, give up.
2236 if (!SafeToInsertStore)
2237 return false;
2238
2239 // Otherwise, this is safe to promote, lets do it!
2240 LLVM_DEBUG(dbgs() << "LICM: Promoting value stored to in loop: " << *SomePtrdo { } while (false)
2241 << '\n')do { } while (false);
2242 ORE->emit([&]() {
2243 return OptimizationRemark(DEBUG_TYPE"licm", "PromoteLoopAccessesToScalar",
2244 LoopUses[0])
2245 << "Moving accesses to memory location out of the loop";
2246 });
2247 ++NumPromoted;
2248
2249 // Look at all the loop uses, and try to merge their locations.
2250 std::vector<const DILocation *> LoopUsesLocs;
2251 for (auto U : LoopUses)
2252 LoopUsesLocs.push_back(U->getDebugLoc().get());
2253 auto DL = DebugLoc(DILocation::getMergedLocations(LoopUsesLocs));
2254
2255 // We use the SSAUpdater interface to insert phi nodes as required.
2256 SmallVector<PHINode *, 16> NewPHIs;
2257 SSAUpdater SSA(&NewPHIs);
2258 LoopPromoter Promoter(SomePtr, LoopUses, SSA, PointerMustAliases, ExitBlocks,
2259 InsertPts, MSSAInsertPts, PIC, CurAST, MSSAU, *LI, DL,
2260 Alignment.value(), SawUnorderedAtomic, AATags,
2261 *SafetyInfo);
2262
2263 // Set up the preheader to have a definition of the value. It is the live-out
2264 // value from the preheader that uses in the loop will use.
2265 LoadInst *PreheaderLoad = new LoadInst(
2266 SomePtr->getType()->getPointerElementType(), SomePtr,
2267 SomePtr->getName() + ".promoted", Preheader->getTerminator());
2268 if (SawUnorderedAtomic)
2269 PreheaderLoad->setOrdering(AtomicOrdering::Unordered);
2270 PreheaderLoad->setAlignment(Alignment);
2271 PreheaderLoad->setDebugLoc(DebugLoc());
2272 if (AATags)
2273 PreheaderLoad->setAAMetadata(AATags);
2274 SSA.AddAvailableValue(Preheader, PreheaderLoad);
2275
2276 if (MSSAU) {
2277 MemoryAccess *PreheaderLoadMemoryAccess = MSSAU->createMemoryAccessInBB(
2278 PreheaderLoad, nullptr, PreheaderLoad->getParent(), MemorySSA::End);
2279 MemoryUse *NewMemUse = cast<MemoryUse>(PreheaderLoadMemoryAccess);
2280 MSSAU->insertUse(NewMemUse, /*RenameUses=*/true);
2281 }
2282
2283 if (MSSAU && VerifyMemorySSA)
2284 MSSAU->getMemorySSA()->verifyMemorySSA();
2285 // Rewrite all the loads in the loop and remember all the definitions from
2286 // stores in the loop.
2287 Promoter.run(LoopUses);
2288
2289 if (MSSAU && VerifyMemorySSA)
2290 MSSAU->getMemorySSA()->verifyMemorySSA();
2291 // If the SSAUpdater didn't use the load in the preheader, just zap it now.
2292 if (PreheaderLoad->use_empty())
2293 eraseInstruction(*PreheaderLoad, *SafetyInfo, CurAST, MSSAU);
2294
2295 return true;
2296}
2297
2298static void foreachMemoryAccess(MemorySSA *MSSA, Loop *L,
2299 function_ref<void(Instruction *)> Fn) {
2300 for (const BasicBlock *BB : L->blocks())
2301 if (const auto *Accesses = MSSA->getBlockAccesses(BB))
2302 for (const auto &Access : *Accesses)
2303 if (const auto *MUD = dyn_cast<MemoryUseOrDef>(&Access))
2304 Fn(MUD->getMemoryInst());
2305}
2306
2307static SmallVector<SmallSetVector<Value *, 8>, 0>
2308collectPromotionCandidates(MemorySSA *MSSA, AliasAnalysis *AA, Loop *L) {
2309 AliasSetTracker AST(*AA);
2310
2311 auto IsPotentiallyPromotable = [L](const Instruction *I) {
2312 if (const auto *SI = dyn_cast<StoreInst>(I))
2313 return L->isLoopInvariant(SI->getPointerOperand());
2314 if (const auto *LI = dyn_cast<LoadInst>(I))
2315 return L->isLoopInvariant(LI->getPointerOperand());
2316 return false;
2317 };
2318
2319 // Populate AST with potentially promotable accesses and remove them from
2320 // MaybePromotable, so they will not be checked again on the next iteration.
2321 SmallPtrSet<Value *, 16> AttemptingPromotion;
2322 foreachMemoryAccess(MSSA, L, [&](Instruction *I) {
2323 if (IsPotentiallyPromotable(I)) {
2324 AttemptingPromotion.insert(I);
2325 AST.add(I);
2326 }
2327 });
2328
2329 // We're only interested in must-alias sets that contain a mod.
2330 SmallVector<const AliasSet *, 8> Sets;
2331 for (AliasSet &AS : AST)
2332 if (!AS.isForwardingAliasSet() && AS.isMod() && AS.isMustAlias())
2333 Sets.push_back(&AS);
2334
2335 if (Sets.empty())
2336 return {}; // Nothing to promote...
2337
2338 // Discard any sets for which there is an aliasing non-promotable access.
2339 foreachMemoryAccess(MSSA, L, [&](Instruction *I) {
2340 if (AttemptingPromotion.contains(I))
2341 return;
2342
2343 llvm::erase_if(Sets, [&](const AliasSet *AS) {
2344 return AS->aliasesUnknownInst(I, *AA);
2345 });
2346 });
2347
2348 SmallVector<SmallSetVector<Value *, 8>, 0> Result;
2349 for (const AliasSet *Set : Sets) {
2350 SmallSetVector<Value *, 8> PointerMustAliases;
2351 for (const auto &ASI : *Set)
2352 PointerMustAliases.insert(ASI.getValue());
2353 Result.push_back(std::move(PointerMustAliases));
2354 }
2355
2356 return Result;
2357}
2358
2359/// Returns an owning pointer to an alias set which incorporates aliasing info
2360/// from L and all subloops of L.
2361std::unique_ptr<AliasSetTracker>
2362LoopInvariantCodeMotion::collectAliasInfoForLoop(Loop *L, LoopInfo *LI,
2363 AAResults *AA) {
2364 auto CurAST = std::make_unique<AliasSetTracker>(*AA);
2365
2366 // Add everything from all the sub loops.
2367 for (Loop *InnerL : L->getSubLoops())
2368 for (BasicBlock *BB : InnerL->blocks())
2369 CurAST->add(*BB);
2370
2371 // And merge in this loop (without anything from inner loops).
2372 for (BasicBlock *BB : L->blocks())
2373 if (LI->getLoopFor(BB) == L)
2374 CurAST->add(*BB);
2375
2376 return CurAST;
2377}
2378
2379static bool pointerInvalidatedByLoop(MemoryLocation MemLoc,
2380 AliasSetTracker *CurAST, Loop *CurLoop,
2381 AAResults *AA) {
2382 // First check to see if any of the basic blocks in CurLoop invalidate *V.
2383 bool isInvalidatedAccordingToAST = CurAST->getAliasSetFor(MemLoc).isMod();
2384
2385 if (!isInvalidatedAccordingToAST || !LICMN2Theshold)
2386 return isInvalidatedAccordingToAST;
2387
2388 // Check with a diagnostic analysis if we can refine the information above.
2389 // This is to identify the limitations of using the AST.
2390 // The alias set mechanism used by LICM has a major weakness in that it
2391 // combines all things which may alias into a single set *before* asking
2392 // modref questions. As a result, a single readonly call within a loop will
2393 // collapse all loads and stores into a single alias set and report
2394 // invalidation if the loop contains any store. For example, readonly calls
2395 // with deopt states have this form and create a general alias set with all
2396 // loads and stores. In order to get any LICM in loops containing possible
2397 // deopt states we need a more precise invalidation of checking the mod ref
2398 // info of each instruction within the loop and LI. This has a complexity of
2399 // O(N^2), so currently, it is used only as a diagnostic tool since the
2400 // default value of LICMN2Threshold is zero.
2401
2402 // Don't look at nested loops.
2403 if (CurLoop->begin() != CurLoop->end())
2404 return true;
2405
2406 int N = 0;
2407 for (BasicBlock *BB : CurLoop->getBlocks())
2408 for (Instruction &I : *BB) {
2409 if (N >= LICMN2Theshold) {
2410 LLVM_DEBUG(dbgs() << "Alasing N2 threshold exhausted for "do { } while (false)
2411 << *(MemLoc.Ptr) << "\n")do { } while (false);
2412 return true;
2413 }
2414 N++;
2415 auto Res = AA->getModRefInfo(&I, MemLoc);
2416 if (isModSet(Res)) {
2417 LLVM_DEBUG(dbgs() << "Aliasing failed on " << I << " for "do { } while (false)
2418 << *(MemLoc.Ptr) << "\n")do { } while (false);
2419 return true;
2420 }
2421 }
2422 LLVM_DEBUG(dbgs() << "Aliasing okay for " << *(MemLoc.Ptr) << "\n")do { } while (false);
2423 return false;
2424}
2425
2426bool pointerInvalidatedByLoopWithMSSA(MemorySSA *MSSA, MemoryUse *MU,
2427 Loop *CurLoop, Instruction &I,
2428 SinkAndHoistLICMFlags &Flags) {
2429 // For hoisting, use the walker to determine safety
2430 if (!Flags.getIsSink()) {
2431 MemoryAccess *Source;
2432 // See declaration of SetLicmMssaOptCap for usage details.
2433 if (Flags.tooManyClobberingCalls())
2434 Source = MU->getDefiningAccess();
2435 else {
2436 Source = MSSA->getSkipSelfWalker()->getClobberingMemoryAccess(MU);
2437 Flags.incrementClobberingCalls();
2438 }
2439 return !MSSA->isLiveOnEntryDef(Source) &&
2440 CurLoop->contains(Source->getBlock());
2441 }
2442
2443 // For sinking, we'd need to check all Defs below this use. The getClobbering
2444 // call will look on the backedge of the loop, but will check aliasing with
2445 // the instructions on the previous iteration.
2446 // For example:
2447 // for (i ... )
2448 // load a[i] ( Use (LoE)
2449 // store a[i] ( 1 = Def (2), with 2 = Phi for the loop.
2450 // i++;
2451 // The load sees no clobbering inside the loop, as the backedge alias check
2452 // does phi translation, and will check aliasing against store a[i-1].
2453 // However sinking the load outside the loop, below the store is incorrect.
2454
2455 // For now, only sink if there are no Defs in the loop, and the existing ones
2456 // precede the use and are in the same block.
2457 // FIXME: Increase precision: Safe to sink if Use post dominates the Def;
2458 // needs PostDominatorTreeAnalysis.
2459 // FIXME: More precise: no Defs that alias this Use.
2460 if (Flags.tooManyMemoryAccesses())
2461 return true;
2462 for (auto *BB : CurLoop->getBlocks())
2463 if (pointerInvalidatedByBlockWithMSSA(*BB, *MSSA, *MU))
2464 return true;
2465 // When sinking, the source block may not be part of the loop so check it.
2466 if (!CurLoop->contains(&I))
2467 return pointerInvalidatedByBlockWithMSSA(*I.getParent(), *MSSA, *MU);
2468
2469 return false;
2470}
2471
2472bool pointerInvalidatedByBlockWithMSSA(BasicBlock &BB, MemorySSA &MSSA,
2473 MemoryUse &MU) {
2474 if (const auto *Accesses = MSSA.getBlockDefs(&BB))
2475 for (const auto &MA : *Accesses)
2476 if (const auto *MD = dyn_cast<MemoryDef>(&MA))
2477 if (MU.getBlock() != MD->getBlock() || !MSSA.locallyDominates(MD, &MU))
2478 return true;
2479 return false;
2480}
2481
2482/// Little predicate that returns true if the specified basic block is in
2483/// a subloop of the current one, not the current one itself.
2484///
2485static bool inSubLoop(BasicBlock *BB, Loop *CurLoop, LoopInfo *LI) {
2486 assert(CurLoop->contains(BB) && "Only valid if BB is IN the loop")((void)0);
2487 return LI->getLoopFor(BB) != CurLoop;
2488}

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IR/Instructions.h

1//===- llvm/Instructions.h - Instruction subclass definitions ---*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file exposes the class definitions of all of the subclasses of the
10// Instruction class. This is meant to be an easy way to get access to all
11// instruction subclasses.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_IR_INSTRUCTIONS_H
16#define LLVM_IR_INSTRUCTIONS_H
17
18#include "llvm/ADT/ArrayRef.h"
19#include "llvm/ADT/Bitfields.h"
20#include "llvm/ADT/MapVector.h"
21#include "llvm/ADT/None.h"
22#include "llvm/ADT/STLExtras.h"
23#include "llvm/ADT/SmallVector.h"
24#include "llvm/ADT/StringRef.h"
25#include "llvm/ADT/Twine.h"
26#include "llvm/ADT/iterator.h"
27#include "llvm/ADT/iterator_range.h"
28#include "llvm/IR/Attributes.h"
29#include "llvm/IR/BasicBlock.h"
30#include "llvm/IR/CallingConv.h"
31#include "llvm/IR/CFG.h"
32#include "llvm/IR/Constant.h"
33#include "llvm/IR/DerivedTypes.h"
34#include "llvm/IR/Function.h"
35#include "llvm/IR/InstrTypes.h"
36#include "llvm/IR/Instruction.h"
37#include "llvm/IR/OperandTraits.h"
38#include "llvm/IR/Type.h"
39#include "llvm/IR/Use.h"
40#include "llvm/IR/User.h"
41#include "llvm/IR/Value.h"
42#include "llvm/Support/AtomicOrdering.h"
43#include "llvm/Support/Casting.h"
44#include "llvm/Support/ErrorHandling.h"
45#include <cassert>
46#include <cstddef>
47#include <cstdint>
48#include <iterator>
49
50namespace llvm {
51
52class APInt;
53class ConstantInt;
54class DataLayout;
55class LLVMContext;
56
57//===----------------------------------------------------------------------===//
58// AllocaInst Class
59//===----------------------------------------------------------------------===//
60
61/// an instruction to allocate memory on the stack
62class AllocaInst : public UnaryInstruction {
63 Type *AllocatedType;
64
65 using AlignmentField = AlignmentBitfieldElementT<0>;
66 using UsedWithInAllocaField = BoolBitfieldElementT<AlignmentField::NextBit>;
67 using SwiftErrorField = BoolBitfieldElementT<UsedWithInAllocaField::NextBit>;
68 static_assert(Bitfield::areContiguous<AlignmentField, UsedWithInAllocaField,
69 SwiftErrorField>(),
70 "Bitfields must be contiguous");
71
72protected:
73 // Note: Instruction needs to be a friend here to call cloneImpl.
74 friend class Instruction;
75
76 AllocaInst *cloneImpl() const;
77
78public:
79 explicit AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize,
80 const Twine &Name, Instruction *InsertBefore);
81 AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize,
82 const Twine &Name, BasicBlock *InsertAtEnd);
83
84 AllocaInst(Type *Ty, unsigned AddrSpace, const Twine &Name,
85 Instruction *InsertBefore);
86 AllocaInst(Type *Ty, unsigned AddrSpace,
87 const Twine &Name, BasicBlock *InsertAtEnd);
88
89 AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize, Align Align,
90 const Twine &Name = "", Instruction *InsertBefore = nullptr);
91 AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize, Align Align,
92 const Twine &Name, BasicBlock *InsertAtEnd);
93
94 /// Return true if there is an allocation size parameter to the allocation
95 /// instruction that is not 1.
96 bool isArrayAllocation() const;
97
98 /// Get the number of elements allocated. For a simple allocation of a single
99 /// element, this will return a constant 1 value.
100 const Value *getArraySize() const { return getOperand(0); }
101 Value *getArraySize() { return getOperand(0); }
102
103 /// Overload to return most specific pointer type.
104 PointerType *getType() const {
105 return cast<PointerType>(Instruction::getType());
106 }
107
108 /// Get allocation size in bits. Returns None if size can't be determined,
109 /// e.g. in case of a VLA.
110 Optional<TypeSize> getAllocationSizeInBits(const DataLayout &DL) const;
111
112 /// Return the type that is being allocated by the instruction.
113 Type *getAllocatedType() const { return AllocatedType; }
114 /// for use only in special circumstances that need to generically
115 /// transform a whole instruction (eg: IR linking and vectorization).
116 void setAllocatedType(Type *Ty) { AllocatedType = Ty; }
117
118 /// Return the alignment of the memory that is being allocated by the
119 /// instruction.
120 Align getAlign() const {
121 return Align(1ULL << getSubclassData<AlignmentField>());
122 }
123
124 void setAlignment(Align Align) {
125 setSubclassData<AlignmentField>(Log2(Align));
126 }
127
128 // FIXME: Remove this one transition to Align is over.
129 unsigned getAlignment() const { return getAlign().value(); }
130
131 /// Return true if this alloca is in the entry block of the function and is a
132 /// constant size. If so, the code generator will fold it into the
133 /// prolog/epilog code, so it is basically free.
134 bool isStaticAlloca() const;
135
136 /// Return true if this alloca is used as an inalloca argument to a call. Such
137 /// allocas are never considered static even if they are in the entry block.
138 bool isUsedWithInAlloca() const {
139 return getSubclassData<UsedWithInAllocaField>();
140 }
141
142 /// Specify whether this alloca is used to represent the arguments to a call.
143 void setUsedWithInAlloca(bool V) {
144 setSubclassData<UsedWithInAllocaField>(V);
145 }
146
147 /// Return true if this alloca is used as a swifterror argument to a call.
148 bool isSwiftError() const { return getSubclassData<SwiftErrorField>(); }
149 /// Specify whether this alloca is used to represent a swifterror.
150 void setSwiftError(bool V) { setSubclassData<SwiftErrorField>(V); }
151
152 // Methods for support type inquiry through isa, cast, and dyn_cast:
153 static bool classof(const Instruction *I) {
154 return (I->getOpcode() == Instruction::Alloca);
155 }
156 static bool classof(const Value *V) {
157 return isa<Instruction>(V) && classof(cast<Instruction>(V));
158 }
159
160private:
161 // Shadow Instruction::setInstructionSubclassData with a private forwarding
162 // method so that subclasses cannot accidentally use it.
163 template <typename Bitfield>
164 void setSubclassData(typename Bitfield::Type Value) {
165 Instruction::setSubclassData<Bitfield>(Value);
166 }
167};
168
169//===----------------------------------------------------------------------===//
170// LoadInst Class
171//===----------------------------------------------------------------------===//
172
173/// An instruction for reading from memory. This uses the SubclassData field in
174/// Value to store whether or not the load is volatile.
175class LoadInst : public UnaryInstruction {
176 using VolatileField = BoolBitfieldElementT<0>;
177 using AlignmentField = AlignmentBitfieldElementT<VolatileField::NextBit>;
178 using OrderingField = AtomicOrderingBitfieldElementT<AlignmentField::NextBit>;
179 static_assert(
180 Bitfield::areContiguous<VolatileField, AlignmentField, OrderingField>(),
181 "Bitfields must be contiguous");
182
183 void AssertOK();
184
185protected:
186 // Note: Instruction needs to be a friend here to call cloneImpl.
187 friend class Instruction;
188
189 LoadInst *cloneImpl() const;
190
191public:
192 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr,
193 Instruction *InsertBefore);
194 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, BasicBlock *InsertAtEnd);
195 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
196 Instruction *InsertBefore);
197 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
198 BasicBlock *InsertAtEnd);
199 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
200 Align Align, Instruction *InsertBefore = nullptr);
201 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
202 Align Align, BasicBlock *InsertAtEnd);
203 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
204 Align Align, AtomicOrdering Order,
205 SyncScope::ID SSID = SyncScope::System,
206 Instruction *InsertBefore = nullptr);
207 LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
208 Align Align, AtomicOrdering Order, SyncScope::ID SSID,
209 BasicBlock *InsertAtEnd);
210
211 /// Return true if this is a load from a volatile memory location.
212 bool isVolatile() const { return getSubclassData<VolatileField>(); }
213
214 /// Specify whether this is a volatile load or not.
215 void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
216
217 /// Return the alignment of the access that is being performed.
218 /// FIXME: Remove this function once transition to Align is over.
219 /// Use getAlign() instead.
220 unsigned getAlignment() const { return getAlign().value(); }
221
222 /// Return the alignment of the access that is being performed.
223 Align getAlign() const {
224 return Align(1ULL << (getSubclassData<AlignmentField>()));
225 }
226
227 void setAlignment(Align Align) {
228 setSubclassData<AlignmentField>(Log2(Align));
229 }
230
231 /// Returns the ordering constraint of this load instruction.
232 AtomicOrdering getOrdering() const {
233 return getSubclassData<OrderingField>();
234 }
235 /// Sets the ordering constraint of this load instruction. May not be Release
236 /// or AcquireRelease.
237 void setOrdering(AtomicOrdering Ordering) {
238 setSubclassData<OrderingField>(Ordering);
239 }
240
241 /// Returns the synchronization scope ID of this load instruction.
242 SyncScope::ID getSyncScopeID() const {
243 return SSID;
244 }
245
246 /// Sets the synchronization scope ID of this load instruction.
247 void setSyncScopeID(SyncScope::ID SSID) {
248 this->SSID = SSID;
249 }
250
251 /// Sets the ordering constraint and the synchronization scope ID of this load
252 /// instruction.
253 void setAtomic(AtomicOrdering Ordering,
254 SyncScope::ID SSID = SyncScope::System) {
255 setOrdering(Ordering);
256 setSyncScopeID(SSID);
257 }
258
259 bool isSimple() const { return !isAtomic() && !isVolatile(); }
260
261 bool isUnordered() const {
262 return (getOrdering() == AtomicOrdering::NotAtomic ||
13
Assuming the condition is false
16
Returning the value 1, which participates in a condition later
263 getOrdering() == AtomicOrdering::Unordered) &&
14
Assuming the condition is true
264 !isVolatile();
15
Assuming the condition is true
265 }
266
267 Value *getPointerOperand() { return getOperand(0); }
268 const Value *getPointerOperand() const { return getOperand(0); }
269 static unsigned getPointerOperandIndex() { return 0U; }
270 Type *getPointerOperandType() const { return getPointerOperand()->getType(); }
271
272 /// Returns the address space of the pointer operand.
273 unsigned getPointerAddressSpace() const {
274 return getPointerOperandType()->getPointerAddressSpace();
275 }
276
277 // Methods for support type inquiry through isa, cast, and dyn_cast:
278 static bool classof(const Instruction *I) {
279 return I->getOpcode() == Instruction::Load;
280 }
281 static bool classof(const Value *V) {
282 return isa<Instruction>(V) && classof(cast<Instruction>(V));
283 }
284
285private:
286 // Shadow Instruction::setInstructionSubclassData with a private forwarding
287 // method so that subclasses cannot accidentally use it.
288 template <typename Bitfield>
289 void setSubclassData(typename Bitfield::Type Value) {
290 Instruction::setSubclassData<Bitfield>(Value);
291 }
292
293 /// The synchronization scope ID of this load instruction. Not quite enough
294 /// room in SubClassData for everything, so synchronization scope ID gets its
295 /// own field.
296 SyncScope::ID SSID;
297};
298
299//===----------------------------------------------------------------------===//
300// StoreInst Class
301//===----------------------------------------------------------------------===//
302
303/// An instruction for storing to memory.
304class StoreInst : public Instruction {
305 using VolatileField = BoolBitfieldElementT<0>;
306 using AlignmentField = AlignmentBitfieldElementT<VolatileField::NextBit>;
307 using OrderingField = AtomicOrderingBitfieldElementT<AlignmentField::NextBit>;
308 static_assert(
309 Bitfield::areContiguous<VolatileField, AlignmentField, OrderingField>(),
310 "Bitfields must be contiguous");
311
312 void AssertOK();
313
314protected:
315 // Note: Instruction needs to be a friend here to call cloneImpl.
316 friend class Instruction;
317
318 StoreInst *cloneImpl() const;
319
320public:
321 StoreInst(Value *Val, Value *Ptr, Instruction *InsertBefore);
322 StoreInst(Value *Val, Value *Ptr, BasicBlock *InsertAtEnd);
323 StoreInst(Value *Val, Value *Ptr, bool isVolatile, Instruction *InsertBefore);
324 StoreInst(Value *Val, Value *Ptr, bool isVolatile, BasicBlock *InsertAtEnd);
325 StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
326 Instruction *InsertBefore = nullptr);
327 StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
328 BasicBlock *InsertAtEnd);
329 StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
330 AtomicOrdering Order, SyncScope::ID SSID = SyncScope::System,
331 Instruction *InsertBefore = nullptr);
332 StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
333 AtomicOrdering Order, SyncScope::ID SSID, BasicBlock *InsertAtEnd);
334
335 // allocate space for exactly two operands
336 void *operator new(size_t S) { return User::operator new(S, 2); }
337 void operator delete(void *Ptr) { User::operator delete(Ptr); }
338
339 /// Return true if this is a store to a volatile memory location.
340 bool isVolatile() const { return getSubclassData<VolatileField>(); }
341
342 /// Specify whether this is a volatile store or not.
343 void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
344
345 /// Transparently provide more efficient getOperand methods.
346 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
347
348 /// Return the alignment of the access that is being performed
349 /// FIXME: Remove this function once transition to Align is over.
350 /// Use getAlign() instead.
351 unsigned getAlignment() const { return getAlign().value(); }
352
353 Align getAlign() const {
354 return Align(1ULL << (getSubclassData<AlignmentField>()));
355 }
356
357 void setAlignment(Align Align) {
358 setSubclassData<AlignmentField>(Log2(Align));
359 }
360
361 /// Returns the ordering constraint of this store instruction.
362 AtomicOrdering getOrdering() const {
363 return getSubclassData<OrderingField>();
364 }
365
366 /// Sets the ordering constraint of this store instruction. May not be
367 /// Acquire or AcquireRelease.
368 void setOrdering(AtomicOrdering Ordering) {
369 setSubclassData<OrderingField>(Ordering);
370 }
371
372 /// Returns the synchronization scope ID of this store instruction.
373 SyncScope::ID getSyncScopeID() const {
374 return SSID;
375 }
376
377 /// Sets the synchronization scope ID of this store instruction.
378 void setSyncScopeID(SyncScope::ID SSID) {
379 this->SSID = SSID;
380 }
381
382 /// Sets the ordering constraint and the synchronization scope ID of this
383 /// store instruction.
384 void setAtomic(AtomicOrdering Ordering,
385 SyncScope::ID SSID = SyncScope::System) {
386 setOrdering(Ordering);
387 setSyncScopeID(SSID);
388 }
389
390 bool isSimple() const { return !isAtomic() && !isVolatile(); }
391
392 bool isUnordered() const {
393 return (getOrdering() == AtomicOrdering::NotAtomic ||
394 getOrdering() == AtomicOrdering::Unordered) &&
395 !isVolatile();
396 }
397
398 Value *getValueOperand() { return getOperand(0); }
399 const Value *getValueOperand() const { return getOperand(0); }
400
401 Value *getPointerOperand() { return getOperand(1); }
402 const Value *getPointerOperand() const { return getOperand(1); }
403 static unsigned getPointerOperandIndex() { return 1U; }
404 Type *getPointerOperandType() const { return getPointerOperand()->getType(); }
405
406 /// Returns the address space of the pointer operand.
407 unsigned getPointerAddressSpace() const {
408 return getPointerOperandType()->getPointerAddressSpace();
409 }
410
411 // Methods for support type inquiry through isa, cast, and dyn_cast:
412 static bool classof(const Instruction *I) {
413 return I->getOpcode() == Instruction::Store;
414 }
415 static bool classof(const Value *V) {
416 return isa<Instruction>(V) && classof(cast<Instruction>(V));
417 }
418
419private:
420 // Shadow Instruction::setInstructionSubclassData with a private forwarding
421 // method so that subclasses cannot accidentally use it.
422 template <typename Bitfield>
423 void setSubclassData(typename Bitfield::Type Value) {
424 Instruction::setSubclassData<Bitfield>(Value);
425 }
426
427 /// The synchronization scope ID of this store instruction. Not quite enough
428 /// room in SubClassData for everything, so synchronization scope ID gets its
429 /// own field.
430 SyncScope::ID SSID;
431};
432
433template <>
434struct OperandTraits<StoreInst> : public FixedNumOperandTraits<StoreInst, 2> {
435};
436
437DEFINE_TRANSPARENT_OPERAND_ACCESSORS(StoreInst, Value)StoreInst::op_iterator StoreInst::op_begin() { return OperandTraits
<StoreInst>::op_begin(this); } StoreInst::const_op_iterator
StoreInst::op_begin() const { return OperandTraits<StoreInst
>::op_begin(const_cast<StoreInst*>(this)); } StoreInst
::op_iterator StoreInst::op_end() { return OperandTraits<StoreInst
>::op_end(this); } StoreInst::const_op_iterator StoreInst::
op_end() const { return OperandTraits<StoreInst>::op_end
(const_cast<StoreInst*>(this)); } Value *StoreInst::getOperand
(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<StoreInst>::op_begin(const_cast
<StoreInst*>(this))[i_nocapture].get()); } void StoreInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
void)0); OperandTraits<StoreInst>::op_begin(this)[i_nocapture
] = Val_nocapture; } unsigned StoreInst::getNumOperands() const
{ return OperandTraits<StoreInst>::operands(this); } template
<int Idx_nocapture> Use &StoreInst::Op() { return this
->OpFrom<Idx_nocapture>(this); } template <int Idx_nocapture
> const Use &StoreInst::Op() const { return this->OpFrom
<Idx_nocapture>(this); }
438
439//===----------------------------------------------------------------------===//
440// FenceInst Class
441//===----------------------------------------------------------------------===//
442
443/// An instruction for ordering other memory operations.
444class FenceInst : public Instruction {
445 using OrderingField = AtomicOrderingBitfieldElementT<0>;
446
447 void Init(AtomicOrdering Ordering, SyncScope::ID SSID);
448
449protected:
450 // Note: Instruction needs to be a friend here to call cloneImpl.
451 friend class Instruction;
452
453 FenceInst *cloneImpl() const;
454
455public:
456 // Ordering may only be Acquire, Release, AcquireRelease, or
457 // SequentiallyConsistent.
458 FenceInst(LLVMContext &C, AtomicOrdering Ordering,
459 SyncScope::ID SSID = SyncScope::System,
460 Instruction *InsertBefore = nullptr);
461 FenceInst(LLVMContext &C, AtomicOrdering Ordering, SyncScope::ID SSID,
462 BasicBlock *InsertAtEnd);
463
464 // allocate space for exactly zero operands
465 void *operator new(size_t S) { return User::operator new(S, 0); }
466 void operator delete(void *Ptr) { User::operator delete(Ptr); }
467
468 /// Returns the ordering constraint of this fence instruction.
469 AtomicOrdering getOrdering() const {
470 return getSubclassData<OrderingField>();
471 }
472
473 /// Sets the ordering constraint of this fence instruction. May only be
474 /// Acquire, Release, AcquireRelease, or SequentiallyConsistent.
475 void setOrdering(AtomicOrdering Ordering) {
476 setSubclassData<OrderingField>(Ordering);
477 }
478
479 /// Returns the synchronization scope ID of this fence instruction.
480 SyncScope::ID getSyncScopeID() const {
481 return SSID;
482 }
483
484 /// Sets the synchronization scope ID of this fence instruction.
485 void setSyncScopeID(SyncScope::ID SSID) {
486 this->SSID = SSID;
487 }
488
489 // Methods for support type inquiry through isa, cast, and dyn_cast:
490 static bool classof(const Instruction *I) {
491 return I->getOpcode() == Instruction::Fence;
492 }
493 static bool classof(const Value *V) {
494 return isa<Instruction>(V) && classof(cast<Instruction>(V));
495 }
496
497private:
498 // Shadow Instruction::setInstructionSubclassData with a private forwarding
499 // method so that subclasses cannot accidentally use it.
500 template <typename Bitfield>
501 void setSubclassData(typename Bitfield::Type Value) {
502 Instruction::setSubclassData<Bitfield>(Value);
503 }
504
505 /// The synchronization scope ID of this fence instruction. Not quite enough
506 /// room in SubClassData for everything, so synchronization scope ID gets its
507 /// own field.
508 SyncScope::ID SSID;
509};
510
511//===----------------------------------------------------------------------===//
512// AtomicCmpXchgInst Class
513//===----------------------------------------------------------------------===//
514
515/// An instruction that atomically checks whether a
516/// specified value is in a memory location, and, if it is, stores a new value
517/// there. The value returned by this instruction is a pair containing the
518/// original value as first element, and an i1 indicating success (true) or
519/// failure (false) as second element.
520///
521class AtomicCmpXchgInst : public Instruction {
522 void Init(Value *Ptr, Value *Cmp, Value *NewVal, Align Align,
523 AtomicOrdering SuccessOrdering, AtomicOrdering FailureOrdering,
524 SyncScope::ID SSID);
525
526 template <unsigned Offset>
527 using AtomicOrderingBitfieldElement =
528 typename Bitfield::Element<AtomicOrdering, Offset, 3,
529 AtomicOrdering::LAST>;
530
531protected:
532 // Note: Instruction needs to be a friend here to call cloneImpl.
533 friend class Instruction;
534
535 AtomicCmpXchgInst *cloneImpl() const;
536
537public:
538 AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
539 AtomicOrdering SuccessOrdering,
540 AtomicOrdering FailureOrdering, SyncScope::ID SSID,
541 Instruction *InsertBefore = nullptr);
542 AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
543 AtomicOrdering SuccessOrdering,
544 AtomicOrdering FailureOrdering, SyncScope::ID SSID,
545 BasicBlock *InsertAtEnd);
546
547 // allocate space for exactly three operands
548 void *operator new(size_t S) { return User::operator new(S, 3); }
549 void operator delete(void *Ptr) { User::operator delete(Ptr); }
550
551 using VolatileField = BoolBitfieldElementT<0>;
552 using WeakField = BoolBitfieldElementT<VolatileField::NextBit>;
553 using SuccessOrderingField =
554 AtomicOrderingBitfieldElementT<WeakField::NextBit>;
555 using FailureOrderingField =
556 AtomicOrderingBitfieldElementT<SuccessOrderingField::NextBit>;
557 using AlignmentField =
558 AlignmentBitfieldElementT<FailureOrderingField::NextBit>;
559 static_assert(
560 Bitfield::areContiguous<VolatileField, WeakField, SuccessOrderingField,
561 FailureOrderingField, AlignmentField>(),
562 "Bitfields must be contiguous");
563
564 /// Return the alignment of the memory that is being allocated by the
565 /// instruction.
566 Align getAlign() const {
567 return Align(1ULL << getSubclassData<AlignmentField>());
568 }
569
570 void setAlignment(Align Align) {
571 setSubclassData<AlignmentField>(Log2(Align));
572 }
573
574 /// Return true if this is a cmpxchg from a volatile memory
575 /// location.
576 ///
577 bool isVolatile() const { return getSubclassData<VolatileField>(); }
578
579 /// Specify whether this is a volatile cmpxchg.
580 ///
581 void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
582
583 /// Return true if this cmpxchg may spuriously fail.
584 bool isWeak() const { return getSubclassData<WeakField>(); }
585
586 void setWeak(bool IsWeak) { setSubclassData<WeakField>(IsWeak); }
587
588 /// Transparently provide more efficient getOperand methods.
589 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
590
591 static bool isValidSuccessOrdering(AtomicOrdering Ordering) {
592 return Ordering != AtomicOrdering::NotAtomic &&
593 Ordering != AtomicOrdering::Unordered;
594 }
595
596 static bool isValidFailureOrdering(AtomicOrdering Ordering) {
597 return Ordering != AtomicOrdering::NotAtomic &&
598 Ordering != AtomicOrdering::Unordered &&
599 Ordering != AtomicOrdering::AcquireRelease &&
600 Ordering != AtomicOrdering::Release;
601 }
602
603 /// Returns the success ordering constraint of this cmpxchg instruction.
604 AtomicOrdering getSuccessOrdering() const {
605 return getSubclassData<SuccessOrderingField>();
606 }
607
608 /// Sets the success ordering constraint of this cmpxchg instruction.
609 void setSuccessOrdering(AtomicOrdering Ordering) {
610 assert(isValidSuccessOrdering(Ordering) &&((void)0)
611 "invalid CmpXchg success ordering")((void)0);
612 setSubclassData<SuccessOrderingField>(Ordering);
613 }
614
615 /// Returns the failure ordering constraint of this cmpxchg instruction.
616 AtomicOrdering getFailureOrdering() const {
617 return getSubclassData<FailureOrderingField>();
618 }
619
620 /// Sets the failure ordering constraint of this cmpxchg instruction.
621 void setFailureOrdering(AtomicOrdering Ordering) {
622 assert(isValidFailureOrdering(Ordering) &&((void)0)
623 "invalid CmpXchg failure ordering")((void)0);
624 setSubclassData<FailureOrderingField>(Ordering);
625 }
626
627 /// Returns a single ordering which is at least as strong as both the
628 /// success and failure orderings for this cmpxchg.
629 AtomicOrdering getMergedOrdering() const {
630 if (getFailureOrdering() == AtomicOrdering::SequentiallyConsistent)
631 return AtomicOrdering::SequentiallyConsistent;
632 if (getFailureOrdering() == AtomicOrdering::Acquire) {
633 if (getSuccessOrdering() == AtomicOrdering::Monotonic)
634 return AtomicOrdering::Acquire;
635 if (getSuccessOrdering() == AtomicOrdering::Release)
636 return AtomicOrdering::AcquireRelease;
637 }
638 return getSuccessOrdering();
639 }
640
641 /// Returns the synchronization scope ID of this cmpxchg instruction.
642 SyncScope::ID getSyncScopeID() const {
643 return SSID;
644 }
645
646 /// Sets the synchronization scope ID of this cmpxchg instruction.
647 void setSyncScopeID(SyncScope::ID SSID) {
648 this->SSID = SSID;
649 }
650
651 Value *getPointerOperand() { return getOperand(0); }
652 const Value *getPointerOperand() const { return getOperand(0); }
653 static unsigned getPointerOperandIndex() { return 0U; }
654
655 Value *getCompareOperand() { return getOperand(1); }
656 const Value *getCompareOperand() const { return getOperand(1); }
657
658 Value *getNewValOperand() { return getOperand(2); }
659 const Value *getNewValOperand() const { return getOperand(2); }
660
661 /// Returns the address space of the pointer operand.
662 unsigned getPointerAddressSpace() const {
663 return getPointerOperand()->getType()->getPointerAddressSpace();
664 }
665
666 /// Returns the strongest permitted ordering on failure, given the
667 /// desired ordering on success.
668 ///
669 /// If the comparison in a cmpxchg operation fails, there is no atomic store
670 /// so release semantics cannot be provided. So this function drops explicit
671 /// Release requests from the AtomicOrdering. A SequentiallyConsistent
672 /// operation would remain SequentiallyConsistent.
673 static AtomicOrdering
674 getStrongestFailureOrdering(AtomicOrdering SuccessOrdering) {
675 switch (SuccessOrdering) {
676 default:
677 llvm_unreachable("invalid cmpxchg success ordering")__builtin_unreachable();
678 case AtomicOrdering::Release:
679 case AtomicOrdering::Monotonic:
680 return AtomicOrdering::Monotonic;
681 case AtomicOrdering::AcquireRelease:
682 case AtomicOrdering::Acquire:
683 return AtomicOrdering::Acquire;
684 case AtomicOrdering::SequentiallyConsistent:
685 return AtomicOrdering::SequentiallyConsistent;
686 }
687 }
688
689 // Methods for support type inquiry through isa, cast, and dyn_cast:
690 static bool classof(const Instruction *I) {
691 return I->getOpcode() == Instruction::AtomicCmpXchg;
692 }
693 static bool classof(const Value *V) {
694 return isa<Instruction>(V) && classof(cast<Instruction>(V));
695 }
696
697private:
698 // Shadow Instruction::setInstructionSubclassData with a private forwarding
699 // method so that subclasses cannot accidentally use it.
700 template <typename Bitfield>
701 void setSubclassData(typename Bitfield::Type Value) {
702 Instruction::setSubclassData<Bitfield>(Value);
703 }
704
705 /// The synchronization scope ID of this cmpxchg instruction. Not quite
706 /// enough room in SubClassData for everything, so synchronization scope ID
707 /// gets its own field.
708 SyncScope::ID SSID;
709};
710
711template <>
712struct OperandTraits<AtomicCmpXchgInst> :
713 public FixedNumOperandTraits<AtomicCmpXchgInst, 3> {
714};
715
716DEFINE_TRANSPARENT_OPERAND_ACCESSORS(AtomicCmpXchgInst, Value)AtomicCmpXchgInst::op_iterator AtomicCmpXchgInst::op_begin() {
return OperandTraits<AtomicCmpXchgInst>::op_begin(this
); } AtomicCmpXchgInst::const_op_iterator AtomicCmpXchgInst::
op_begin() const { return OperandTraits<AtomicCmpXchgInst>
::op_begin(const_cast<AtomicCmpXchgInst*>(this)); } AtomicCmpXchgInst
::op_iterator AtomicCmpXchgInst::op_end() { return OperandTraits
<AtomicCmpXchgInst>::op_end(this); } AtomicCmpXchgInst::
const_op_iterator AtomicCmpXchgInst::op_end() const { return OperandTraits
<AtomicCmpXchgInst>::op_end(const_cast<AtomicCmpXchgInst
*>(this)); } Value *AtomicCmpXchgInst::getOperand(unsigned
i_nocapture) const { ((void)0); return cast_or_null<Value
>( OperandTraits<AtomicCmpXchgInst>::op_begin(const_cast
<AtomicCmpXchgInst*>(this))[i_nocapture].get()); } void
AtomicCmpXchgInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((void)0); OperandTraits<AtomicCmpXchgInst>::op_begin
(this)[i_nocapture] = Val_nocapture; } unsigned AtomicCmpXchgInst
::getNumOperands() const { return OperandTraits<AtomicCmpXchgInst
>::operands(this); } template <int Idx_nocapture> Use
&AtomicCmpXchgInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
AtomicCmpXchgInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }
717
718//===----------------------------------------------------------------------===//
719// AtomicRMWInst Class
720//===----------------------------------------------------------------------===//
721
722/// an instruction that atomically reads a memory location,
723/// combines it with another value, and then stores the result back. Returns
724/// the old value.
725///
726class AtomicRMWInst : public Instruction {
727protected:
728 // Note: Instruction needs to be a friend here to call cloneImpl.
729 friend class Instruction;
730
731 AtomicRMWInst *cloneImpl() const;
732
733public:
734 /// This enumeration lists the possible modifications atomicrmw can make. In
735 /// the descriptions, 'p' is the pointer to the instruction's memory location,
736 /// 'old' is the initial value of *p, and 'v' is the other value passed to the
737 /// instruction. These instructions always return 'old'.
738 enum BinOp : unsigned {
739 /// *p = v
740 Xchg,
741 /// *p = old + v
742 Add,
743 /// *p = old - v
744 Sub,
745 /// *p = old & v
746 And,
747 /// *p = ~(old & v)
748 Nand,
749 /// *p = old | v
750 Or,
751 /// *p = old ^ v
752 Xor,
753 /// *p = old >signed v ? old : v
754 Max,
755 /// *p = old <signed v ? old : v
756 Min,
757 /// *p = old >unsigned v ? old : v
758 UMax,
759 /// *p = old <unsigned v ? old : v
760 UMin,
761
762 /// *p = old + v
763 FAdd,
764
765 /// *p = old - v
766 FSub,
767
768 FIRST_BINOP = Xchg,
769 LAST_BINOP = FSub,
770 BAD_BINOP
771 };
772
773private:
774 template <unsigned Offset>
775 using AtomicOrderingBitfieldElement =
776 typename Bitfield::Element<AtomicOrdering, Offset, 3,
777 AtomicOrdering::LAST>;
778
779 template <unsigned Offset>
780 using BinOpBitfieldElement =
781 typename Bitfield::Element<BinOp, Offset, 4, BinOp::LAST_BINOP>;
782
783public:
784 AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
785 AtomicOrdering Ordering, SyncScope::ID SSID,
786 Instruction *InsertBefore = nullptr);
787 AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
788 AtomicOrdering Ordering, SyncScope::ID SSID,
789 BasicBlock *InsertAtEnd);
790
791 // allocate space for exactly two operands
792 void *operator new(size_t S) { return User::operator new(S, 2); }
793 void operator delete(void *Ptr) { User::operator delete(Ptr); }
794
795 using VolatileField = BoolBitfieldElementT<0>;
796 using AtomicOrderingField =
797 AtomicOrderingBitfieldElementT<VolatileField::NextBit>;
798 using OperationField = BinOpBitfieldElement<AtomicOrderingField::NextBit>;
799 using AlignmentField = AlignmentBitfieldElementT<OperationField::NextBit>;
800 static_assert(Bitfield::areContiguous<VolatileField, AtomicOrderingField,
801 OperationField, AlignmentField>(),
802 "Bitfields must be contiguous");
803
804 BinOp getOperation() const { return getSubclassData<OperationField>(); }
805
806 static StringRef getOperationName(BinOp Op);
807
808 static bool isFPOperation(BinOp Op) {
809 switch (Op) {
810 case AtomicRMWInst::FAdd:
811 case AtomicRMWInst::FSub:
812 return true;
813 default:
814 return false;
815 }
816 }
817
818 void setOperation(BinOp Operation) {
819 setSubclassData<OperationField>(Operation);
820 }
821
822 /// Return the alignment of the memory that is being allocated by the
823 /// instruction.
824 Align getAlign() const {
825 return Align(1ULL << getSubclassData<AlignmentField>());
826 }
827
828 void setAlignment(Align Align) {
829 setSubclassData<AlignmentField>(Log2(Align));
830 }
831
832 /// Return true if this is a RMW on a volatile memory location.
833 ///
834 bool isVolatile() const { return getSubclassData<VolatileField>(); }
835
836 /// Specify whether this is a volatile RMW or not.
837 ///
838 void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
839
840 /// Transparently provide more efficient getOperand methods.
841 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
842
843 /// Returns the ordering constraint of this rmw instruction.
844 AtomicOrdering getOrdering() const {
845 return getSubclassData<AtomicOrderingField>();
846 }
847
848 /// Sets the ordering constraint of this rmw instruction.
849 void setOrdering(AtomicOrdering Ordering) {
850 assert(Ordering != AtomicOrdering::NotAtomic &&((void)0)
851 "atomicrmw instructions can only be atomic.")((void)0);
852 setSubclassData<AtomicOrderingField>(Ordering);
853 }
854
855 /// Returns the synchronization scope ID of this rmw instruction.
856 SyncScope::ID getSyncScopeID() const {
857 return SSID;
858 }
859
860 /// Sets the synchronization scope ID of this rmw instruction.
861 void setSyncScopeID(SyncScope::ID SSID) {
862 this->SSID = SSID;
863 }
864
865 Value *getPointerOperand() { return getOperand(0); }
866 const Value *getPointerOperand() const { return getOperand(0); }
867 static unsigned getPointerOperandIndex() { return 0U; }
868
869 Value *getValOperand() { return getOperand(1); }
870 const Value *getValOperand() const { return getOperand(1); }
871
872 /// Returns the address space of the pointer operand.
873 unsigned getPointerAddressSpace() const {
874 return getPointerOperand()->getType()->getPointerAddressSpace();
875 }
876
877 bool isFloatingPointOperation() const {
878 return isFPOperation(getOperation());
879 }
880
881 // Methods for support type inquiry through isa, cast, and dyn_cast:
882 static bool classof(const Instruction *I) {
883 return I->getOpcode() == Instruction::AtomicRMW;
884 }
885 static bool classof(const Value *V) {
886 return isa<Instruction>(V) && classof(cast<Instruction>(V));
887 }
888
889private:
890 void Init(BinOp Operation, Value *Ptr, Value *Val, Align Align,
891 AtomicOrdering Ordering, SyncScope::ID SSID);
892
893 // Shadow Instruction::setInstructionSubclassData with a private forwarding
894 // method so that subclasses cannot accidentally use it.
895 template <typename Bitfield>
896 void setSubclassData(typename Bitfield::Type Value) {
897 Instruction::setSubclassData<Bitfield>(Value);
898 }
899
900 /// The synchronization scope ID of this rmw instruction. Not quite enough
901 /// room in SubClassData for everything, so synchronization scope ID gets its
902 /// own field.
903 SyncScope::ID SSID;
904};
905
906template <>
907struct OperandTraits<AtomicRMWInst>
908 : public FixedNumOperandTraits<AtomicRMWInst,2> {
909};
910
911DEFINE_TRANSPARENT_OPERAND_ACCESSORS(AtomicRMWInst, Value)AtomicRMWInst::op_iterator AtomicRMWInst::op_begin() { return
OperandTraits<AtomicRMWInst>::op_begin(this); } AtomicRMWInst
::const_op_iterator AtomicRMWInst::op_begin() const { return OperandTraits
<AtomicRMWInst>::op_begin(const_cast<AtomicRMWInst*>
(this)); } AtomicRMWInst::op_iterator AtomicRMWInst::op_end()
{ return OperandTraits<AtomicRMWInst>::op_end(this); }
AtomicRMWInst::const_op_iterator AtomicRMWInst::op_end() const
{ return OperandTraits<AtomicRMWInst>::op_end(const_cast
<AtomicRMWInst*>(this)); } Value *AtomicRMWInst::getOperand
(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<AtomicRMWInst>::op_begin(const_cast
<AtomicRMWInst*>(this))[i_nocapture].get()); } void AtomicRMWInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
void)0); OperandTraits<AtomicRMWInst>::op_begin(this)[i_nocapture
] = Val_nocapture; } unsigned AtomicRMWInst::getNumOperands()
const { return OperandTraits<AtomicRMWInst>::operands(
this); } template <int Idx_nocapture> Use &AtomicRMWInst
::Op() { return this->OpFrom<Idx_nocapture>(this); }
template <int Idx_nocapture> const Use &AtomicRMWInst
::Op() const { return this->OpFrom<Idx_nocapture>(this
); }
912
913//===----------------------------------------------------------------------===//
914// GetElementPtrInst Class
915//===----------------------------------------------------------------------===//
916
917// checkGEPType - Simple wrapper function to give a better assertion failure
918// message on bad indexes for a gep instruction.
919//
920inline Type *checkGEPType(Type *Ty) {
921 assert(Ty && "Invalid GetElementPtrInst indices for type!")((void)0);
922 return Ty;
923}
924
925/// an instruction for type-safe pointer arithmetic to
926/// access elements of arrays and structs
927///
928class GetElementPtrInst : public Instruction {
929 Type *SourceElementType;
930 Type *ResultElementType;
931
932 GetElementPtrInst(const GetElementPtrInst &GEPI);
933
934 /// Constructors - Create a getelementptr instruction with a base pointer an
935 /// list of indices. The first ctor can optionally insert before an existing
936 /// instruction, the second appends the new instruction to the specified
937 /// BasicBlock.
938 inline GetElementPtrInst(Type *PointeeType, Value *Ptr,
939 ArrayRef<Value *> IdxList, unsigned Values,
940 const Twine &NameStr, Instruction *InsertBefore);
941 inline GetElementPtrInst(Type *PointeeType, Value *Ptr,
942 ArrayRef<Value *> IdxList, unsigned Values,
943 const Twine &NameStr, BasicBlock *InsertAtEnd);
944
945 void init(Value *Ptr, ArrayRef<Value *> IdxList, const Twine &NameStr);
946
947protected:
948 // Note: Instruction needs to be a friend here to call cloneImpl.
949 friend class Instruction;
950
951 GetElementPtrInst *cloneImpl() const;
952
953public:
954 static GetElementPtrInst *Create(Type *PointeeType, Value *Ptr,
955 ArrayRef<Value *> IdxList,
956 const Twine &NameStr = "",
957 Instruction *InsertBefore = nullptr) {
958 unsigned Values = 1 + unsigned(IdxList.size());
959 assert(PointeeType && "Must specify element type")((void)0);
960 assert(cast<PointerType>(Ptr->getType()->getScalarType())((void)0)
961 ->isOpaqueOrPointeeTypeMatches(PointeeType))((void)0);
962 return new (Values) GetElementPtrInst(PointeeType, Ptr, IdxList, Values,
963 NameStr, InsertBefore);
964 }
965
966 static GetElementPtrInst *Create(Type *PointeeType, Value *Ptr,
967 ArrayRef<Value *> IdxList,
968 const Twine &NameStr,
969 BasicBlock *InsertAtEnd) {
970 unsigned Values = 1 + unsigned(IdxList.size());
971 assert(PointeeType && "Must specify element type")((void)0);
972 assert(cast<PointerType>(Ptr->getType()->getScalarType())((void)0)
973 ->isOpaqueOrPointeeTypeMatches(PointeeType))((void)0);
974 return new (Values) GetElementPtrInst(PointeeType, Ptr, IdxList, Values,
975 NameStr, InsertAtEnd);
976 }
977
978 LLVM_ATTRIBUTE_DEPRECATED(static GetElementPtrInst *CreateInBounds([[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr = "", Instruction
*InsertBefore = nullptr)
979 Value *Ptr, ArrayRef<Value *> IdxList, const Twine &NameStr = "",[[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr = "", Instruction
*InsertBefore = nullptr)
980 Instruction *InsertBefore = nullptr),[[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr = "", Instruction
*InsertBefore = nullptr)
981 "Use the version with explicit element type instead")[[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr = "", Instruction
*InsertBefore = nullptr)
{
982 return CreateInBounds(
983 Ptr->getType()->getScalarType()->getPointerElementType(), Ptr, IdxList,
984 NameStr, InsertBefore);
985 }
986
987 /// Create an "inbounds" getelementptr. See the documentation for the
988 /// "inbounds" flag in LangRef.html for details.
989 static GetElementPtrInst *
990 CreateInBounds(Type *PointeeType, Value *Ptr, ArrayRef<Value *> IdxList,
991 const Twine &NameStr = "",
992 Instruction *InsertBefore = nullptr) {
993 GetElementPtrInst *GEP =
994 Create(PointeeType, Ptr, IdxList, NameStr, InsertBefore);
995 GEP->setIsInBounds(true);
996 return GEP;
997 }
998
999 LLVM_ATTRIBUTE_DEPRECATED(static GetElementPtrInst *CreateInBounds([[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr, BasicBlock
*InsertAtEnd)
1000 Value *Ptr, ArrayRef<Value *> IdxList, const Twine &NameStr,[[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr, BasicBlock
*InsertAtEnd)
1001 BasicBlock *InsertAtEnd),[[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr, BasicBlock
*InsertAtEnd)
1002 "Use the version with explicit element type instead")[[deprecated("Use the version with explicit element type instead"
)]] static GetElementPtrInst *CreateInBounds( Value *Ptr, ArrayRef
<Value *> IdxList, const Twine &NameStr, BasicBlock
*InsertAtEnd)
{
1003 return CreateInBounds(
1004 Ptr->getType()->getScalarType()->getPointerElementType(), Ptr, IdxList,
1005 NameStr, InsertAtEnd);
1006 }
1007
1008 static GetElementPtrInst *CreateInBounds(Type *PointeeType, Value *Ptr,
1009 ArrayRef<Value *> IdxList,
1010 const Twine &NameStr,
1011 BasicBlock *InsertAtEnd) {
1012 GetElementPtrInst *GEP =
1013 Create(PointeeType, Ptr, IdxList, NameStr, InsertAtEnd);
1014 GEP->setIsInBounds(true);
1015 return GEP;
1016 }
1017
1018 /// Transparently provide more efficient getOperand methods.
1019 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
1020
1021 Type *getSourceElementType() const { return SourceElementType; }
1022
1023 void setSourceElementType(Type *Ty) { SourceElementType = Ty; }
1024 void setResultElementType(Type *Ty) { ResultElementType = Ty; }
1025
1026 Type *getResultElementType() const {
1027 assert(cast<PointerType>(getType()->getScalarType())((void)0)
1028 ->isOpaqueOrPointeeTypeMatches(ResultElementType))((void)0);
1029 return ResultElementType;
1030 }
1031
1032 /// Returns the address space of this instruction's pointer type.
1033 unsigned getAddressSpace() const {
1034 // Note that this is always the same as the pointer operand's address space
1035 // and that is cheaper to compute, so cheat here.
1036 return getPointerAddressSpace();
1037 }
1038
1039 /// Returns the result type of a getelementptr with the given source
1040 /// element type and indexes.
1041 ///
1042 /// Null is returned if the indices are invalid for the specified
1043 /// source element type.
1044 static Type *getIndexedType(Type *Ty, ArrayRef<Value *> IdxList);
1045 static Type *getIndexedType(Type *Ty, ArrayRef<Constant *> IdxList);
1046 static Type *getIndexedType(Type *Ty, ArrayRef<uint64_t> IdxList);
1047
1048 /// Return the type of the element at the given index of an indexable
1049 /// type. This is equivalent to "getIndexedType(Agg, {Zero, Idx})".
1050 ///
1051 /// Returns null if the type can't be indexed, or the given index is not
1052 /// legal for the given type.
1053 static Type *getTypeAtIndex(Type *Ty, Value *Idx);
1054 static Type *getTypeAtIndex(Type *Ty, uint64_t Idx);
1055
1056 inline op_iterator idx_begin() { return op_begin()+1; }
1057 inline const_op_iterator idx_begin() const { return op_begin()+1; }
1058 inline op_iterator idx_end() { return op_end(); }
1059 inline const_op_iterator idx_end() const { return op_end(); }
1060
1061 inline iterator_range<op_iterator> indices() {
1062 return make_range(idx_begin(), idx_end());
1063 }
1064
1065 inline iterator_range<const_op_iterator> indices() const {
1066 return make_range(idx_begin(), idx_end());
1067 }
1068
1069 Value *getPointerOperand() {
1070 return getOperand(0);
1071 }
1072 const Value *getPointerOperand() const {
1073 return getOperand(0);
1074 }
1075 static unsigned getPointerOperandIndex() {
1076 return 0U; // get index for modifying correct operand.
1077 }
1078
1079 /// Method to return the pointer operand as a
1080 /// PointerType.
1081 Type *getPointerOperandType() const {
1082 return getPointerOperand()->getType();
1083 }
1084
1085 /// Returns the address space of the pointer operand.
1086 unsigned getPointerAddressSpace() const {
1087 return getPointerOperandType()->getPointerAddressSpace();
1088 }
1089
1090 /// Returns the pointer type returned by the GEP
1091 /// instruction, which may be a vector of pointers.
1092 static Type *getGEPReturnType(Type *ElTy, Value *Ptr,
1093 ArrayRef<Value *> IdxList) {
1094 PointerType *OrigPtrTy = cast<PointerType>(Ptr->getType()->getScalarType());
1095 unsigned AddrSpace = OrigPtrTy->getAddressSpace();
1096 Type *ResultElemTy = checkGEPType(getIndexedType(ElTy, IdxList));
1097 Type *PtrTy = OrigPtrTy->isOpaque()
1098 ? PointerType::get(OrigPtrTy->getContext(), AddrSpace)
1099 : PointerType::get(ResultElemTy, AddrSpace);
1100 // Vector GEP
1101 if (auto *PtrVTy = dyn_cast<VectorType>(Ptr->getType())) {
1102 ElementCount EltCount = PtrVTy->getElementCount();
1103 return VectorType::get(PtrTy, EltCount);
1104 }
1105 for (Value *Index : IdxList)
1106 if (auto *IndexVTy = dyn_cast<VectorType>(Index->getType())) {
1107 ElementCount EltCount = IndexVTy->getElementCount();
1108 return VectorType::get(PtrTy, EltCount);
1109 }
1110 // Scalar GEP
1111 return PtrTy;
1112 }
1113
1114 unsigned getNumIndices() const { // Note: always non-negative
1115 return getNumOperands() - 1;
1116 }
1117
1118 bool hasIndices() const {
1119 return getNumOperands() > 1;
1120 }
1121
1122 /// Return true if all of the indices of this GEP are
1123 /// zeros. If so, the result pointer and the first operand have the same
1124 /// value, just potentially different types.
1125 bool hasAllZeroIndices() const;
1126
1127 /// Return true if all of the indices of this GEP are
1128 /// constant integers. If so, the result pointer and the first operand have
1129 /// a constant offset between them.
1130 bool hasAllConstantIndices() const;
1131
1132 /// Set or clear the inbounds flag on this GEP instruction.
1133 /// See LangRef.html for the meaning of inbounds on a getelementptr.
1134 void setIsInBounds(bool b = true);
1135
1136 /// Determine whether the GEP has the inbounds flag.
1137 bool isInBounds() const;
1138
1139 /// Accumulate the constant address offset of this GEP if possible.
1140 ///
1141 /// This routine accepts an APInt into which it will accumulate the constant
1142 /// offset of this GEP if the GEP is in fact constant. If the GEP is not
1143 /// all-constant, it returns false and the value of the offset APInt is
1144 /// undefined (it is *not* preserved!). The APInt passed into this routine
1145 /// must be at least as wide as the IntPtr type for the address space of
1146 /// the base GEP pointer.
1147 bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const;
1148 bool collectOffset(const DataLayout &DL, unsigned BitWidth,
1149 MapVector<Value *, APInt> &VariableOffsets,
1150 APInt &ConstantOffset) const;
1151 // Methods for support type inquiry through isa, cast, and dyn_cast:
1152 static bool classof(const Instruction *I) {
1153 return (I->getOpcode() == Instruction::GetElementPtr);
1154 }
1155 static bool classof(const Value *V) {
1156 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1157 }
1158};
1159
1160template <>
1161struct OperandTraits<GetElementPtrInst> :
1162 public VariadicOperandTraits<GetElementPtrInst, 1> {
1163};
1164
1165GetElementPtrInst::GetElementPtrInst(Type *PointeeType, Value *Ptr,
1166 ArrayRef<Value *> IdxList, unsigned Values,
1167 const Twine &NameStr,
1168 Instruction *InsertBefore)
1169 : Instruction(getGEPReturnType(PointeeType, Ptr, IdxList), GetElementPtr,
1170 OperandTraits<GetElementPtrInst>::op_end(this) - Values,
1171 Values, InsertBefore),
1172 SourceElementType(PointeeType),
1173 ResultElementType(getIndexedType(PointeeType, IdxList)) {
1174 assert(cast<PointerType>(getType()->getScalarType())((void)0)
1175 ->isOpaqueOrPointeeTypeMatches(ResultElementType))((void)0);
1176 init(Ptr, IdxList, NameStr);
1177}
1178
1179GetElementPtrInst::GetElementPtrInst(Type *PointeeType, Value *Ptr,
1180 ArrayRef<Value *> IdxList, unsigned Values,
1181 const Twine &NameStr,
1182 BasicBlock *InsertAtEnd)
1183 : Instruction(getGEPReturnType(PointeeType, Ptr, IdxList), GetElementPtr,
1184 OperandTraits<GetElementPtrInst>::op_end(this) - Values,
1185 Values, InsertAtEnd),
1186 SourceElementType(PointeeType),
1187 ResultElementType(getIndexedType(PointeeType, IdxList)) {
1188 assert(cast<PointerType>(getType()->getScalarType())((void)0)
1189 ->isOpaqueOrPointeeTypeMatches(ResultElementType))((void)0);
1190 init(Ptr, IdxList, NameStr);
1191}
1192
1193DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GetElementPtrInst, Value)GetElementPtrInst::op_iterator GetElementPtrInst::op_begin() {
return OperandTraits<GetElementPtrInst>::op_begin(this
); } GetElementPtrInst::const_op_iterator GetElementPtrInst::
op_begin() const { return OperandTraits<GetElementPtrInst>
::op_begin(const_cast<GetElementPtrInst*>(this)); } GetElementPtrInst
::op_iterator GetElementPtrInst::op_end() { return OperandTraits
<GetElementPtrInst>::op_end(this); } GetElementPtrInst::
const_op_iterator GetElementPtrInst::op_end() const { return OperandTraits
<GetElementPtrInst>::op_end(const_cast<GetElementPtrInst
*>(this)); } Value *GetElementPtrInst::getOperand(unsigned
i_nocapture) const { ((void)0); return cast_or_null<Value
>( OperandTraits<GetElementPtrInst>::op_begin(const_cast
<GetElementPtrInst*>(this))[i_nocapture].get()); } void
GetElementPtrInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((void)0); OperandTraits<GetElementPtrInst>::op_begin
(this)[i_nocapture] = Val_nocapture; } unsigned GetElementPtrInst
::getNumOperands() const { return OperandTraits<GetElementPtrInst
>::operands(this); } template <int Idx_nocapture> Use
&GetElementPtrInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
GetElementPtrInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }
1194
1195//===----------------------------------------------------------------------===//
1196// ICmpInst Class
1197//===----------------------------------------------------------------------===//
1198
1199/// This instruction compares its operands according to the predicate given
1200/// to the constructor. It only operates on integers or pointers. The operands
1201/// must be identical types.
1202/// Represent an integer comparison operator.
1203class ICmpInst: public CmpInst {
1204 void AssertOK() {
1205 assert(isIntPredicate() &&((void)0)
1206 "Invalid ICmp predicate value")((void)0);
1207 assert(getOperand(0)->getType() == getOperand(1)->getType() &&((void)0)
1208 "Both operands to ICmp instruction are not of the same type!")((void)0);
1209 // Check that the operands are the right type
1210 assert((getOperand(0)->getType()->isIntOrIntVectorTy() ||((void)0)
1211 getOperand(0)->getType()->isPtrOrPtrVectorTy()) &&((void)0)
1212 "Invalid operand types for ICmp instruction")((void)0);
1213 }
1214
1215protected:
1216 // Note: Instruction needs to be a friend here to call cloneImpl.
1217 friend class Instruction;
1218
1219 /// Clone an identical ICmpInst
1220 ICmpInst *cloneImpl() const;
1221
1222public:
1223 /// Constructor with insert-before-instruction semantics.
1224 ICmpInst(
1225 Instruction *InsertBefore, ///< Where to insert
1226 Predicate pred, ///< The predicate to use for the comparison
1227 Value *LHS, ///< The left-hand-side of the expression
1228 Value *RHS, ///< The right-hand-side of the expression
1229 const Twine &NameStr = "" ///< Name of the instruction
1230 ) : CmpInst(makeCmpResultType(LHS->getType()),
1231 Instruction::ICmp, pred, LHS, RHS, NameStr,
1232 InsertBefore) {
1233#ifndef NDEBUG1
1234 AssertOK();
1235#endif
1236 }
1237
1238 /// Constructor with insert-at-end semantics.
1239 ICmpInst(
1240 BasicBlock &InsertAtEnd, ///< Block to insert into.
1241 Predicate pred, ///< The predicate to use for the comparison
1242 Value *LHS, ///< The left-hand-side of the expression
1243 Value *RHS, ///< The right-hand-side of the expression
1244 const Twine &NameStr = "" ///< Name of the instruction
1245 ) : CmpInst(makeCmpResultType(LHS->getType()),
1246 Instruction::ICmp, pred, LHS, RHS, NameStr,
1247 &InsertAtEnd) {
1248#ifndef NDEBUG1
1249 AssertOK();
1250#endif
1251 }
1252
1253 /// Constructor with no-insertion semantics
1254 ICmpInst(
1255 Predicate pred, ///< The predicate to use for the comparison
1256 Value *LHS, ///< The left-hand-side of the expression
1257 Value *RHS, ///< The right-hand-side of the expression
1258 const Twine &NameStr = "" ///< Name of the instruction
1259 ) : CmpInst(makeCmpResultType(LHS->getType()),
1260 Instruction::ICmp, pred, LHS, RHS, NameStr) {
1261#ifndef NDEBUG1
1262 AssertOK();
1263#endif
1264 }
1265
1266 /// For example, EQ->EQ, SLE->SLE, UGT->SGT, etc.
1267 /// @returns the predicate that would be the result if the operand were
1268 /// regarded as signed.
1269 /// Return the signed version of the predicate
1270 Predicate getSignedPredicate() const {
1271 return getSignedPredicate(getPredicate());
1272 }
1273
1274 /// This is a static version that you can use without an instruction.
1275 /// Return the signed version of the predicate.
1276 static Predicate getSignedPredicate(Predicate pred);
1277
1278 /// For example, EQ->EQ, SLE->ULE, UGT->UGT, etc.
1279 /// @returns the predicate that would be the result if the operand were
1280 /// regarded as unsigned.
1281 /// Return the unsigned version of the predicate
1282 Predicate getUnsignedPredicate() const {
1283 return getUnsignedPredicate(getPredicate());
1284 }
1285
1286 /// This is a static version that you can use without an instruction.
1287 /// Return the unsigned version of the predicate.
1288 static Predicate getUnsignedPredicate(Predicate pred);
1289
1290 /// Return true if this predicate is either EQ or NE. This also
1291 /// tests for commutativity.
1292 static bool isEquality(Predicate P) {
1293 return P == ICMP_EQ || P == ICMP_NE;
1294 }
1295
1296 /// Return true if this predicate is either EQ or NE. This also
1297 /// tests for commutativity.
1298 bool isEquality() const {
1299 return isEquality(getPredicate());
1300 }
1301
1302 /// @returns true if the predicate of this ICmpInst is commutative
1303 /// Determine if this relation is commutative.
1304 bool isCommutative() const { return isEquality(); }
1305
1306 /// Return true if the predicate is relational (not EQ or NE).
1307 ///
1308 bool isRelational() const {
1309 return !isEquality();
1310 }
1311
1312 /// Return true if the predicate is relational (not EQ or NE).
1313 ///
1314 static bool isRelational(Predicate P) {
1315 return !isEquality(P);
1316 }
1317
1318 /// Return true if the predicate is SGT or UGT.
1319 ///
1320 static bool isGT(Predicate P) {
1321 return P == ICMP_SGT || P == ICMP_UGT;
1322 }
1323
1324 /// Return true if the predicate is SLT or ULT.
1325 ///
1326 static bool isLT(Predicate P) {
1327 return P == ICMP_SLT || P == ICMP_ULT;
1328 }
1329
1330 /// Return true if the predicate is SGE or UGE.
1331 ///
1332 static bool isGE(Predicate P) {
1333 return P == ICMP_SGE || P == ICMP_UGE;
1334 }
1335
1336 /// Return true if the predicate is SLE or ULE.
1337 ///
1338 static bool isLE(Predicate P) {
1339 return P == ICMP_SLE || P == ICMP_ULE;
1340 }
1341
1342 /// Exchange the two operands to this instruction in such a way that it does
1343 /// not modify the semantics of the instruction. The predicate value may be
1344 /// changed to retain the same result if the predicate is order dependent
1345 /// (e.g. ult).
1346 /// Swap operands and adjust predicate.
1347 void swapOperands() {
1348 setPredicate(getSwappedPredicate());
1349 Op<0>().swap(Op<1>());
1350 }
1351
1352 // Methods for support type inquiry through isa, cast, and dyn_cast:
1353 static bool classof(const Instruction *I) {
1354 return I->getOpcode() == Instruction::ICmp;
1355 }
1356 static bool classof(const Value *V) {
1357 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1358 }
1359};
1360
1361//===----------------------------------------------------------------------===//
1362// FCmpInst Class
1363//===----------------------------------------------------------------------===//
1364
1365/// This instruction compares its operands according to the predicate given
1366/// to the constructor. It only operates on floating point values or packed
1367/// vectors of floating point values. The operands must be identical types.
1368/// Represents a floating point comparison operator.
1369class FCmpInst: public CmpInst {
1370 void AssertOK() {
1371 assert(isFPPredicate() && "Invalid FCmp predicate value")((void)0);
1372 assert(getOperand(0)->getType() == getOperand(1)->getType() &&((void)0)
1373 "Both operands to FCmp instruction are not of the same type!")((void)0);
1374 // Check that the operands are the right type
1375 assert(getOperand(0)->getType()->isFPOrFPVectorTy() &&((void)0)
1376 "Invalid operand types for FCmp instruction")((void)0);
1377 }
1378
1379protected:
1380 // Note: Instruction needs to be a friend here to call cloneImpl.
1381 friend class Instruction;
1382
1383 /// Clone an identical FCmpInst
1384 FCmpInst *cloneImpl() const;
1385
1386public:
1387 /// Constructor with insert-before-instruction semantics.
1388 FCmpInst(
1389 Instruction *InsertBefore, ///< Where to insert
1390 Predicate pred, ///< The predicate to use for the comparison
1391 Value *LHS, ///< The left-hand-side of the expression
1392 Value *RHS, ///< The right-hand-side of the expression
1393 const Twine &NameStr = "" ///< Name of the instruction
1394 ) : CmpInst(makeCmpResultType(LHS->getType()),
1395 Instruction::FCmp, pred, LHS, RHS, NameStr,
1396 InsertBefore) {
1397 AssertOK();
1398 }
1399
1400 /// Constructor with insert-at-end semantics.
1401 FCmpInst(
1402 BasicBlock &InsertAtEnd, ///< Block to insert into.
1403 Predicate pred, ///< The predicate to use for the comparison
1404 Value *LHS, ///< The left-hand-side of the expression
1405 Value *RHS, ///< The right-hand-side of the expression
1406 const Twine &NameStr = "" ///< Name of the instruction
1407 ) : CmpInst(makeCmpResultType(LHS->getType()),
1408 Instruction::FCmp, pred, LHS, RHS, NameStr,
1409 &InsertAtEnd) {
1410 AssertOK();
1411 }
1412
1413 /// Constructor with no-insertion semantics
1414 FCmpInst(
1415 Predicate Pred, ///< The predicate to use for the comparison
1416 Value *LHS, ///< The left-hand-side of the expression
1417 Value *RHS, ///< The right-hand-side of the expression
1418 const Twine &NameStr = "", ///< Name of the instruction
1419 Instruction *FlagsSource = nullptr
1420 ) : CmpInst(makeCmpResultType(LHS->getType()), Instruction::FCmp, Pred, LHS,
1421 RHS, NameStr, nullptr, FlagsSource) {
1422 AssertOK();
1423 }
1424
1425 /// @returns true if the predicate of this instruction is EQ or NE.
1426 /// Determine if this is an equality predicate.
1427 static bool isEquality(Predicate Pred) {
1428 return Pred == FCMP_OEQ || Pred == FCMP_ONE || Pred == FCMP_UEQ ||
1429 Pred == FCMP_UNE;
1430 }
1431
1432 /// @returns true if the predicate of this instruction is EQ or NE.
1433 /// Determine if this is an equality predicate.
1434 bool isEquality() const { return isEquality(getPredicate()); }
1435
1436 /// @returns true if the predicate of this instruction is commutative.
1437 /// Determine if this is a commutative predicate.
1438 bool isCommutative() const {
1439 return isEquality() ||
1440 getPredicate() == FCMP_FALSE ||
1441 getPredicate() == FCMP_TRUE ||
1442 getPredicate() == FCMP_ORD ||
1443 getPredicate() == FCMP_UNO;
1444 }
1445
1446 /// @returns true if the predicate is relational (not EQ or NE).
1447 /// Determine if this a relational predicate.
1448 bool isRelational() const { return !isEquality(); }
1449
1450 /// Exchange the two operands to this instruction in such a way that it does
1451 /// not modify the semantics of the instruction. The predicate value may be
1452 /// changed to retain the same result if the predicate is order dependent
1453 /// (e.g. ult).
1454 /// Swap operands and adjust predicate.
1455 void swapOperands() {
1456 setPredicate(getSwappedPredicate());
1457 Op<0>().swap(Op<1>());
1458 }
1459
1460 /// Methods for support type inquiry through isa, cast, and dyn_cast:
1461 static bool classof(const Instruction *I) {
1462 return I->getOpcode() == Instruction::FCmp;
1463 }
1464 static bool classof(const Value *V) {
1465 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1466 }
1467};
1468
1469//===----------------------------------------------------------------------===//
1470/// This class represents a function call, abstracting a target
1471/// machine's calling convention. This class uses low bit of the SubClassData
1472/// field to indicate whether or not this is a tail call. The rest of the bits
1473/// hold the calling convention of the call.
1474///
1475class CallInst : public CallBase {
1476 CallInst(const CallInst &CI);
1477
1478 /// Construct a CallInst given a range of arguments.
1479 /// Construct a CallInst from a range of arguments
1480 inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1481 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
1482 Instruction *InsertBefore);
1483
1484 inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1485 const Twine &NameStr, Instruction *InsertBefore)
1486 : CallInst(Ty, Func, Args, None, NameStr, InsertBefore) {}
1487
1488 /// Construct a CallInst given a range of arguments.
1489 /// Construct a CallInst from a range of arguments
1490 inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1491 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
1492 BasicBlock *InsertAtEnd);
1493
1494 explicit CallInst(FunctionType *Ty, Value *F, const Twine &NameStr,
1495 Instruction *InsertBefore);
1496
1497 CallInst(FunctionType *ty, Value *F, const Twine &NameStr,
1498 BasicBlock *InsertAtEnd);
1499
1500 void init(FunctionType *FTy, Value *Func, ArrayRef<Value *> Args,
1501 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);
1502 void init(FunctionType *FTy, Value *Func, const Twine &NameStr);
1503
1504 /// Compute the number of operands to allocate.
1505 static int ComputeNumOperands(int NumArgs, int NumBundleInputs = 0) {
1506 // We need one operand for the called function, plus the input operand
1507 // counts provided.
1508 return 1 + NumArgs + NumBundleInputs;
1509 }
1510
1511protected:
1512 // Note: Instruction needs to be a friend here to call cloneImpl.
1513 friend class Instruction;
1514
1515 CallInst *cloneImpl() const;
1516
1517public:
1518 static CallInst *Create(FunctionType *Ty, Value *F, const Twine &NameStr = "",
1519 Instruction *InsertBefore = nullptr) {
1520 return new (ComputeNumOperands(0)) CallInst(Ty, F, NameStr, InsertBefore);
1521 }
1522
1523 static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1524 const Twine &NameStr,
1525 Instruction *InsertBefore = nullptr) {
1526 return new (ComputeNumOperands(Args.size()))
1527 CallInst(Ty, Func, Args, None, NameStr, InsertBefore);
1528 }
1529
1530 static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1531 ArrayRef<OperandBundleDef> Bundles = None,
1532 const Twine &NameStr = "",
1533 Instruction *InsertBefore = nullptr) {
1534 const int NumOperands =
1535 ComputeNumOperands(Args.size(), CountBundleInputs(Bundles));
1536 const unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);
1537
1538 return new (NumOperands, DescriptorBytes)
1539 CallInst(Ty, Func, Args, Bundles, NameStr, InsertBefore);
1540 }
1541
1542 static CallInst *Create(FunctionType *Ty, Value *F, const Twine &NameStr,
1543 BasicBlock *InsertAtEnd) {
1544 return new (ComputeNumOperands(0)) CallInst(Ty, F, NameStr, InsertAtEnd);
1545 }
1546
1547 static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1548 const Twine &NameStr, BasicBlock *InsertAtEnd) {
1549 return new (ComputeNumOperands(Args.size()))
1550 CallInst(Ty, Func, Args, None, NameStr, InsertAtEnd);
1551 }
1552
1553 static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1554 ArrayRef<OperandBundleDef> Bundles,
1555 const Twine &NameStr, BasicBlock *InsertAtEnd) {
1556 const int NumOperands =
1557 ComputeNumOperands(Args.size(), CountBundleInputs(Bundles));
1558 const unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);
1559
1560 return new (NumOperands, DescriptorBytes)
1561 CallInst(Ty, Func, Args, Bundles, NameStr, InsertAtEnd);
1562 }
1563
1564 static CallInst *Create(FunctionCallee Func, const Twine &NameStr = "",
1565 Instruction *InsertBefore = nullptr) {
1566 return Create(Func.getFunctionType(), Func.getCallee(), NameStr,
1567 InsertBefore);
1568 }
1569
1570 static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
1571 ArrayRef<OperandBundleDef> Bundles = None,
1572 const Twine &NameStr = "",
1573 Instruction *InsertBefore = nullptr) {
1574 return Create(Func.getFunctionType(), Func.getCallee(), Args, Bundles,
1575 NameStr, InsertBefore);
1576 }
1577
1578 static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
1579 const Twine &NameStr,
1580 Instruction *InsertBefore = nullptr) {
1581 return Create(Func.getFunctionType(), Func.getCallee(), Args, NameStr,
1582 InsertBefore);
1583 }
1584
1585 static CallInst *Create(FunctionCallee Func, const Twine &NameStr,
1586 BasicBlock *InsertAtEnd) {
1587 return Create(Func.getFunctionType(), Func.getCallee(), NameStr,
1588 InsertAtEnd);
1589 }
1590
1591 static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
1592 const Twine &NameStr, BasicBlock *InsertAtEnd) {
1593 return Create(Func.getFunctionType(), Func.getCallee(), Args, NameStr,
1594 InsertAtEnd);
1595 }
1596
1597 static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
1598 ArrayRef<OperandBundleDef> Bundles,
1599 const Twine &NameStr, BasicBlock *InsertAtEnd) {
1600 return Create(Func.getFunctionType(), Func.getCallee(), Args, Bundles,
1601 NameStr, InsertAtEnd);
1602 }
1603
1604 /// Create a clone of \p CI with a different set of operand bundles and
1605 /// insert it before \p InsertPt.
1606 ///
1607 /// The returned call instruction is identical \p CI in every way except that
1608 /// the operand bundles for the new instruction are set to the operand bundles
1609 /// in \p Bundles.
1610 static CallInst *Create(CallInst *CI, ArrayRef<OperandBundleDef> Bundles,
1611 Instruction *InsertPt = nullptr);
1612
1613 /// Generate the IR for a call to malloc:
1614 /// 1. Compute the malloc call's argument as the specified type's size,
1615 /// possibly multiplied by the array size if the array size is not
1616 /// constant 1.
1617 /// 2. Call malloc with that argument.
1618 /// 3. Bitcast the result of the malloc call to the specified type.
1619 static Instruction *CreateMalloc(Instruction *InsertBefore, Type *IntPtrTy,
1620 Type *AllocTy, Value *AllocSize,
1621 Value *ArraySize = nullptr,
1622 Function *MallocF = nullptr,
1623 const Twine &Name = "");
1624 static Instruction *CreateMalloc(BasicBlock *InsertAtEnd, Type *IntPtrTy,
1625 Type *AllocTy, Value *AllocSize,
1626 Value *ArraySize = nullptr,
1627 Function *MallocF = nullptr,
1628 const Twine &Name = "");
1629 static Instruction *CreateMalloc(Instruction *InsertBefore, Type *IntPtrTy,
1630 Type *AllocTy, Value *AllocSize,
1631 Value *ArraySize = nullptr,
1632 ArrayRef<OperandBundleDef> Bundles = None,
1633 Function *MallocF = nullptr,
1634 const Twine &Name = "");
1635 static Instruction *CreateMalloc(BasicBlock *InsertAtEnd, Type *IntPtrTy,
1636 Type *AllocTy, Value *AllocSize,
1637 Value *ArraySize = nullptr,
1638 ArrayRef<OperandBundleDef> Bundles = None,
1639 Function *MallocF = nullptr,
1640 const Twine &Name = "");
1641 /// Generate the IR for a call to the builtin free function.
1642 static Instruction *CreateFree(Value *Source, Instruction *InsertBefore);
1643 static Instruction *CreateFree(Value *Source, BasicBlock *InsertAtEnd);
1644 static Instruction *CreateFree(Value *Source,
1645 ArrayRef<OperandBundleDef> Bundles,
1646 Instruction *InsertBefore);
1647 static Instruction *CreateFree(Value *Source,
1648 ArrayRef<OperandBundleDef> Bundles,
1649 BasicBlock *InsertAtEnd);
1650
1651 // Note that 'musttail' implies 'tail'.
1652 enum TailCallKind : unsigned {
1653 TCK_None = 0,
1654 TCK_Tail = 1,
1655 TCK_MustTail = 2,
1656 TCK_NoTail = 3,
1657 TCK_LAST = TCK_NoTail
1658 };
1659
1660 using TailCallKindField = Bitfield::Element<TailCallKind, 0, 2, TCK_LAST>;
1661 static_assert(
1662 Bitfield::areContiguous<TailCallKindField, CallBase::CallingConvField>(),
1663 "Bitfields must be contiguous");
1664
1665 TailCallKind getTailCallKind() const {
1666 return getSubclassData<TailCallKindField>();
1667 }
1668
1669 bool isTailCall() const {
1670 TailCallKind Kind = getTailCallKind();
1671 return Kind == TCK_Tail || Kind == TCK_MustTail;
1672 }
1673
1674 bool isMustTailCall() const { return getTailCallKind() == TCK_MustTail; }
1675
1676 bool isNoTailCall() const { return getTailCallKind() == TCK_NoTail; }
1677
1678 void setTailCallKind(TailCallKind TCK) {
1679 setSubclassData<TailCallKindField>(TCK);
1680 }
1681
1682 void setTailCall(bool IsTc = true) {
1683 setTailCallKind(IsTc ? TCK_Tail : TCK_None);
1684 }
1685
1686 /// Return true if the call can return twice
1687 bool canReturnTwice() const { return hasFnAttr(Attribute::ReturnsTwice); }
1688 void setCanReturnTwice() {
1689 addAttribute(AttributeList::FunctionIndex, Attribute::ReturnsTwice);
1690 }
1691
1692 // Methods for support type inquiry through isa, cast, and dyn_cast:
1693 static bool classof(const Instruction *I) {
1694 return I->getOpcode() == Instruction::Call;
1695 }
1696 static bool classof(const Value *V) {
1697 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1698 }
1699
1700 /// Updates profile metadata by scaling it by \p S / \p T.
1701 void updateProfWeight(uint64_t S, uint64_t T);
1702
1703private:
1704 // Shadow Instruction::setInstructionSubclassData with a private forwarding
1705 // method so that subclasses cannot accidentally use it.
1706 template <typename Bitfield>
1707 void setSubclassData(typename Bitfield::Type Value) {
1708 Instruction::setSubclassData<Bitfield>(Value);
1709 }
1710};
1711
1712CallInst::CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1713 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
1714 BasicBlock *InsertAtEnd)
1715 : CallBase(Ty->getReturnType(), Instruction::Call,
1716 OperandTraits<CallBase>::op_end(this) -
1717 (Args.size() + CountBundleInputs(Bundles) + 1),
1718 unsigned(Args.size() + CountBundleInputs(Bundles) + 1),
1719 InsertAtEnd) {
1720 init(Ty, Func, Args, Bundles, NameStr);
1721}
1722
1723CallInst::CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
1724 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
1725 Instruction *InsertBefore)
1726 : CallBase(Ty->getReturnType(), Instruction::Call,
1727 OperandTraits<CallBase>::op_end(this) -
1728 (Args.size() + CountBundleInputs(Bundles) + 1),
1729 unsigned(Args.size() + CountBundleInputs(Bundles) + 1),
1730 InsertBefore) {
1731 init(Ty, Func, Args, Bundles, NameStr);
1732}
1733
1734//===----------------------------------------------------------------------===//
1735// SelectInst Class
1736//===----------------------------------------------------------------------===//
1737
1738/// This class represents the LLVM 'select' instruction.
1739///
1740class SelectInst : public Instruction {
1741 SelectInst(Value *C, Value *S1, Value *S2, const Twine &NameStr,
1742 Instruction *InsertBefore)
1743 : Instruction(S1->getType(), Instruction::Select,
1744 &Op<0>(), 3, InsertBefore) {
1745 init(C, S1, S2);
1746 setName(NameStr);
1747 }
1748
1749 SelectInst(Value *C, Value *S1, Value *S2, const Twine &NameStr,
1750 BasicBlock *InsertAtEnd)
1751 : Instruction(S1->getType(), Instruction::Select,
1752 &Op<0>(), 3, InsertAtEnd) {
1753 init(C, S1, S2);
1754 setName(NameStr);
1755 }
1756
1757 void init(Value *C, Value *S1, Value *S2) {
1758 assert(!areInvalidOperands(C, S1, S2) && "Invalid operands for select")((void)0);
1759 Op<0>() = C;
1760 Op<1>() = S1;
1761 Op<2>() = S2;
1762 }
1763
1764protected:
1765 // Note: Instruction needs to be a friend here to call cloneImpl.
1766 friend class Instruction;
1767
1768 SelectInst *cloneImpl() const;
1769
1770public:
1771 static SelectInst *Create(Value *C, Value *S1, Value *S2,
1772 const Twine &NameStr = "",
1773 Instruction *InsertBefore = nullptr,
1774 Instruction *MDFrom = nullptr) {
1775 SelectInst *Sel = new(3) SelectInst(C, S1, S2, NameStr, InsertBefore);
1776 if (MDFrom)
1777 Sel->copyMetadata(*MDFrom);
1778 return Sel;
1779 }
1780
1781 static SelectInst *Create(Value *C, Value *S1, Value *S2,
1782 const Twine &NameStr,
1783 BasicBlock *InsertAtEnd) {
1784 return new(3) SelectInst(C, S1, S2, NameStr, InsertAtEnd);
1785 }
1786
1787 const Value *getCondition() const { return Op<0>(); }
1788 const Value *getTrueValue() const { return Op<1>(); }
1789 const Value *getFalseValue() const { return Op<2>(); }
1790 Value *getCondition() { return Op<0>(); }
1791 Value *getTrueValue() { return Op<1>(); }
1792 Value *getFalseValue() { return Op<2>(); }
1793
1794 void setCondition(Value *V) { Op<0>() = V; }
1795 void setTrueValue(Value *V) { Op<1>() = V; }
1796 void setFalseValue(Value *V) { Op<2>() = V; }
1797
1798 /// Swap the true and false values of the select instruction.
1799 /// This doesn't swap prof metadata.
1800 void swapValues() { Op<1>().swap(Op<2>()); }
1801
1802 /// Return a string if the specified operands are invalid
1803 /// for a select operation, otherwise return null.
1804 static const char *areInvalidOperands(Value *Cond, Value *True, Value *False);
1805
1806 /// Transparently provide more efficient getOperand methods.
1807 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
1808
1809 OtherOps getOpcode() const {
1810 return static_cast<OtherOps>(Instruction::getOpcode());
1811 }
1812
1813 // Methods for support type inquiry through isa, cast, and dyn_cast:
1814 static bool classof(const Instruction *I) {
1815 return I->getOpcode() == Instruction::Select;
1816 }
1817 static bool classof(const Value *V) {
1818 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1819 }
1820};
1821
1822template <>
1823struct OperandTraits<SelectInst> : public FixedNumOperandTraits<SelectInst, 3> {
1824};
1825
1826DEFINE_TRANSPARENT_OPERAND_ACCESSORS(SelectInst, Value)SelectInst::op_iterator SelectInst::op_begin() { return OperandTraits
<SelectInst>::op_begin(this); } SelectInst::const_op_iterator
SelectInst::op_begin() const { return OperandTraits<SelectInst
>::op_begin(const_cast<SelectInst*>(this)); } SelectInst
::op_iterator SelectInst::op_end() { return OperandTraits<
SelectInst>::op_end(this); } SelectInst::const_op_iterator
SelectInst::op_end() const { return OperandTraits<SelectInst
>::op_end(const_cast<SelectInst*>(this)); } Value *SelectInst
::getOperand(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<SelectInst>::op_begin(const_cast
<SelectInst*>(this))[i_nocapture].get()); } void SelectInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
void)0); OperandTraits<SelectInst>::op_begin(this)[i_nocapture
] = Val_nocapture; } unsigned SelectInst::getNumOperands() const
{ return OperandTraits<SelectInst>::operands(this); } template
<int Idx_nocapture> Use &SelectInst::Op() { return
this->OpFrom<Idx_nocapture>(this); } template <int
Idx_nocapture> const Use &SelectInst::Op() const { return
this->OpFrom<Idx_nocapture>(this); }
1827
1828//===----------------------------------------------------------------------===//
1829// VAArgInst Class
1830//===----------------------------------------------------------------------===//
1831
1832/// This class represents the va_arg llvm instruction, which returns
1833/// an argument of the specified type given a va_list and increments that list
1834///
1835class VAArgInst : public UnaryInstruction {
1836protected:
1837 // Note: Instruction needs to be a friend here to call cloneImpl.
1838 friend class Instruction;
1839
1840 VAArgInst *cloneImpl() const;
1841
1842public:
1843 VAArgInst(Value *List, Type *Ty, const Twine &NameStr = "",
1844 Instruction *InsertBefore = nullptr)
1845 : UnaryInstruction(Ty, VAArg, List, InsertBefore) {
1846 setName(NameStr);
1847 }
1848
1849 VAArgInst(Value *List, Type *Ty, const Twine &NameStr,
1850 BasicBlock *InsertAtEnd)
1851 : UnaryInstruction(Ty, VAArg, List, InsertAtEnd) {
1852 setName(NameStr);
1853 }
1854
1855 Value *getPointerOperand() { return getOperand(0); }
1856 const Value *getPointerOperand() const { return getOperand(0); }
1857 static unsigned getPointerOperandIndex() { return 0U; }
1858
1859 // Methods for support type inquiry through isa, cast, and dyn_cast:
1860 static bool classof(const Instruction *I) {
1861 return I->getOpcode() == VAArg;
1862 }
1863 static bool classof(const Value *V) {
1864 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1865 }
1866};
1867
1868//===----------------------------------------------------------------------===//
1869// ExtractElementInst Class
1870//===----------------------------------------------------------------------===//
1871
1872/// This instruction extracts a single (scalar)
1873/// element from a VectorType value
1874///
1875class ExtractElementInst : public Instruction {
1876 ExtractElementInst(Value *Vec, Value *Idx, const Twine &NameStr = "",
1877 Instruction *InsertBefore = nullptr);
1878 ExtractElementInst(Value *Vec, Value *Idx, const Twine &NameStr,
1879 BasicBlock *InsertAtEnd);
1880
1881protected:
1882 // Note: Instruction needs to be a friend here to call cloneImpl.
1883 friend class Instruction;
1884
1885 ExtractElementInst *cloneImpl() const;
1886
1887public:
1888 static ExtractElementInst *Create(Value *Vec, Value *Idx,
1889 const Twine &NameStr = "",
1890 Instruction *InsertBefore = nullptr) {
1891 return new(2) ExtractElementInst(Vec, Idx, NameStr, InsertBefore);
1892 }
1893
1894 static ExtractElementInst *Create(Value *Vec, Value *Idx,
1895 const Twine &NameStr,
1896 BasicBlock *InsertAtEnd) {
1897 return new(2) ExtractElementInst(Vec, Idx, NameStr, InsertAtEnd);
1898 }
1899
1900 /// Return true if an extractelement instruction can be
1901 /// formed with the specified operands.
1902 static bool isValidOperands(const Value *Vec, const Value *Idx);
1903
1904 Value *getVectorOperand() { return Op<0>(); }
1905 Value *getIndexOperand() { return Op<1>(); }
1906 const Value *getVectorOperand() const { return Op<0>(); }
1907 const Value *getIndexOperand() const { return Op<1>(); }
1908
1909 VectorType *getVectorOperandType() const {
1910 return cast<VectorType>(getVectorOperand()->getType());
1911 }
1912
1913 /// Transparently provide more efficient getOperand methods.
1914 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
1915
1916 // Methods for support type inquiry through isa, cast, and dyn_cast:
1917 static bool classof(const Instruction *I) {
1918 return I->getOpcode() == Instruction::ExtractElement;
1919 }
1920 static bool classof(const Value *V) {
1921 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1922 }
1923};
1924
1925template <>
1926struct OperandTraits<ExtractElementInst> :
1927 public FixedNumOperandTraits<ExtractElementInst, 2> {
1928};
1929
1930DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ExtractElementInst, Value)ExtractElementInst::op_iterator ExtractElementInst::op_begin(
) { return OperandTraits<ExtractElementInst>::op_begin(
this); } ExtractElementInst::const_op_iterator ExtractElementInst
::op_begin() const { return OperandTraits<ExtractElementInst
>::op_begin(const_cast<ExtractElementInst*>(this)); }
ExtractElementInst::op_iterator ExtractElementInst::op_end()
{ return OperandTraits<ExtractElementInst>::op_end(this
); } ExtractElementInst::const_op_iterator ExtractElementInst
::op_end() const { return OperandTraits<ExtractElementInst
>::op_end(const_cast<ExtractElementInst*>(this)); } Value
*ExtractElementInst::getOperand(unsigned i_nocapture) const {
((void)0); return cast_or_null<Value>( OperandTraits<
ExtractElementInst>::op_begin(const_cast<ExtractElementInst
*>(this))[i_nocapture].get()); } void ExtractElementInst::
setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((void
)0); OperandTraits<ExtractElementInst>::op_begin(this)[
i_nocapture] = Val_nocapture; } unsigned ExtractElementInst::
getNumOperands() const { return OperandTraits<ExtractElementInst
>::operands(this); } template <int Idx_nocapture> Use
&ExtractElementInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
ExtractElementInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }
1931
1932//===----------------------------------------------------------------------===//
1933// InsertElementInst Class
1934//===----------------------------------------------------------------------===//
1935
1936/// This instruction inserts a single (scalar)
1937/// element into a VectorType value
1938///
1939class InsertElementInst : public Instruction {
1940 InsertElementInst(Value *Vec, Value *NewElt, Value *Idx,
1941 const Twine &NameStr = "",
1942 Instruction *InsertBefore = nullptr);
1943 InsertElementInst(Value *Vec, Value *NewElt, Value *Idx, const Twine &NameStr,
1944 BasicBlock *InsertAtEnd);
1945
1946protected:
1947 // Note: Instruction needs to be a friend here to call cloneImpl.
1948 friend class Instruction;
1949
1950 InsertElementInst *cloneImpl() const;
1951
1952public:
1953 static InsertElementInst *Create(Value *Vec, Value *NewElt, Value *Idx,
1954 const Twine &NameStr = "",
1955 Instruction *InsertBefore = nullptr) {
1956 return new(3) InsertElementInst(Vec, NewElt, Idx, NameStr, InsertBefore);
1957 }
1958
1959 static InsertElementInst *Create(Value *Vec, Value *NewElt, Value *Idx,
1960 const Twine &NameStr,
1961 BasicBlock *InsertAtEnd) {
1962 return new(3) InsertElementInst(Vec, NewElt, Idx, NameStr, InsertAtEnd);
1963 }
1964
1965 /// Return true if an insertelement instruction can be
1966 /// formed with the specified operands.
1967 static bool isValidOperands(const Value *Vec, const Value *NewElt,
1968 const Value *Idx);
1969
1970 /// Overload to return most specific vector type.
1971 ///
1972 VectorType *getType() const {
1973 return cast<VectorType>(Instruction::getType());
1974 }
1975
1976 /// Transparently provide more efficient getOperand methods.
1977 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
1978
1979 // Methods for support type inquiry through isa, cast, and dyn_cast:
1980 static bool classof(const Instruction *I) {
1981 return I->getOpcode() == Instruction::InsertElement;
1982 }
1983 static bool classof(const Value *V) {
1984 return isa<Instruction>(V) && classof(cast<Instruction>(V));
1985 }
1986};
1987
1988template <>
1989struct OperandTraits<InsertElementInst> :
1990 public FixedNumOperandTraits<InsertElementInst, 3> {
1991};
1992
1993DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertElementInst, Value)InsertElementInst::op_iterator InsertElementInst::op_begin() {
return OperandTraits<InsertElementInst>::op_begin(this
); } InsertElementInst::const_op_iterator InsertElementInst::
op_begin() const { return OperandTraits<InsertElementInst>
::op_begin(const_cast<InsertElementInst*>(this)); } InsertElementInst
::op_iterator InsertElementInst::op_end() { return OperandTraits
<InsertElementInst>::op_end(this); } InsertElementInst::
const_op_iterator InsertElementInst::op_end() const { return OperandTraits
<InsertElementInst>::op_end(const_cast<InsertElementInst
*>(this)); } Value *InsertElementInst::getOperand(unsigned
i_nocapture) const { ((void)0); return cast_or_null<Value
>( OperandTraits<InsertElementInst>::op_begin(const_cast
<InsertElementInst*>(this))[i_nocapture].get()); } void
InsertElementInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((void)0); OperandTraits<InsertElementInst>::op_begin
(this)[i_nocapture] = Val_nocapture; } unsigned InsertElementInst
::getNumOperands() const { return OperandTraits<InsertElementInst
>::operands(this); } template <int Idx_nocapture> Use
&InsertElementInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
InsertElementInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }
1994
1995//===----------------------------------------------------------------------===//
1996// ShuffleVectorInst Class
1997//===----------------------------------------------------------------------===//
1998
1999constexpr int UndefMaskElem = -1;
2000
2001/// This instruction constructs a fixed permutation of two
2002/// input vectors.
2003///
2004/// For each element of the result vector, the shuffle mask selects an element
2005/// from one of the input vectors to copy to the result. Non-negative elements
2006/// in the mask represent an index into the concatenated pair of input vectors.
2007/// UndefMaskElem (-1) specifies that the result element is undefined.
2008///
2009/// For scalable vectors, all the elements of the mask must be 0 or -1. This
2010/// requirement may be relaxed in the future.
2011class ShuffleVectorInst : public Instruction {
2012 SmallVector<int, 4> ShuffleMask;
2013 Constant *ShuffleMaskForBitcode;
2014
2015protected:
2016 // Note: Instruction needs to be a friend here to call cloneImpl.
2017 friend class Instruction;
2018
2019 ShuffleVectorInst *cloneImpl() const;
2020
2021public:
2022 ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
2023 const Twine &NameStr = "",
2024 Instruction *InsertBefor = nullptr);
2025 ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
2026 const Twine &NameStr, BasicBlock *InsertAtEnd);
2027 ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
2028 const Twine &NameStr = "",
2029 Instruction *InsertBefor = nullptr);
2030 ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
2031 const Twine &NameStr, BasicBlock *InsertAtEnd);
2032
2033 void *operator new(size_t S) { return User::operator new(S, 2); }
2034 void operator delete(void *Ptr) { return User::operator delete(Ptr); }
2035
2036 /// Swap the operands and adjust the mask to preserve the semantics
2037 /// of the instruction.
2038 void commute();
2039
2040 /// Return true if a shufflevector instruction can be
2041 /// formed with the specified operands.
2042 static bool isValidOperands(const Value *V1, const Value *V2,
2043 const Value *Mask);
2044 static bool isValidOperands(const Value *V1, const Value *V2,
2045 ArrayRef<int> Mask);
2046
2047 /// Overload to return most specific vector type.
2048 ///
2049 VectorType *getType() const {
2050 return cast<VectorType>(Instruction::getType());
2051 }
2052
2053 /// Transparently provide more efficient getOperand methods.
2054 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
2055
2056 /// Return the shuffle mask value of this instruction for the given element
2057 /// index. Return UndefMaskElem if the element is undef.
2058 int getMaskValue(unsigned Elt) const { return ShuffleMask[Elt]; }
2059
2060 /// Convert the input shuffle mask operand to a vector of integers. Undefined
2061 /// elements of the mask are returned as UndefMaskElem.
2062 static void getShuffleMask(const Constant *Mask,
2063 SmallVectorImpl<int> &Result);
2064
2065 /// Return the mask for this instruction as a vector of integers. Undefined
2066 /// elements of the mask are returned as UndefMaskElem.
2067 void getShuffleMask(SmallVectorImpl<int> &Result) const {
2068 Result.assign(ShuffleMask.begin(), ShuffleMask.end());
2069 }
2070
2071 /// Return the mask for this instruction, for use in bitcode.
2072 ///
2073 /// TODO: This is temporary until we decide a new bitcode encoding for
2074 /// shufflevector.
2075 Constant *getShuffleMaskForBitcode() const { return ShuffleMaskForBitcode; }
2076
2077 static Constant *convertShuffleMaskForBitcode(ArrayRef<int> Mask,
2078 Type *ResultTy);
2079
2080 void setShuffleMask(ArrayRef<int> Mask);
2081
2082 ArrayRef<int> getShuffleMask() const { return ShuffleMask; }
2083
2084 /// Return true if this shuffle returns a vector with a different number of
2085 /// elements than its source vectors.
2086 /// Examples: shufflevector <4 x n> A, <4 x n> B, <1,2,3>
2087 /// shufflevector <4 x n> A, <4 x n> B, <1,2,3,4,5>
2088 bool changesLength() const {
2089 unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
2090 ->getElementCount()
2091 .getKnownMinValue();
2092 unsigned NumMaskElts = ShuffleMask.size();
2093 return NumSourceElts != NumMaskElts;
2094 }
2095
2096 /// Return true if this shuffle returns a vector with a greater number of
2097 /// elements than its source vectors.
2098 /// Example: shufflevector <2 x n> A, <2 x n> B, <1,2,3>
2099 bool increasesLength() const {
2100 unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
2101 ->getElementCount()
2102 .getKnownMinValue();
2103 unsigned NumMaskElts = ShuffleMask.size();
2104 return NumSourceElts < NumMaskElts;
2105 }
2106
2107 /// Return true if this shuffle mask chooses elements from exactly one source
2108 /// vector.
2109 /// Example: <7,5,undef,7>
2110 /// This assumes that vector operands are the same length as the mask.
2111 static bool isSingleSourceMask(ArrayRef<int> Mask);
2112 static bool isSingleSourceMask(const Constant *Mask) {
2113 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2114 SmallVector<int, 16> MaskAsInts;
2115 getShuffleMask(Mask, MaskAsInts);
2116 return isSingleSourceMask(MaskAsInts);
2117 }
2118
2119 /// Return true if this shuffle chooses elements from exactly one source
2120 /// vector without changing the length of that vector.
2121 /// Example: shufflevector <4 x n> A, <4 x n> B, <3,0,undef,3>
2122 /// TODO: Optionally allow length-changing shuffles.
2123 bool isSingleSource() const {
2124 return !changesLength() && isSingleSourceMask(ShuffleMask);
2125 }
2126
2127 /// Return true if this shuffle mask chooses elements from exactly one source
2128 /// vector without lane crossings. A shuffle using this mask is not
2129 /// necessarily a no-op because it may change the number of elements from its
2130 /// input vectors or it may provide demanded bits knowledge via undef lanes.
2131 /// Example: <undef,undef,2,3>
2132 static bool isIdentityMask(ArrayRef<int> Mask);
2133 static bool isIdentityMask(const Constant *Mask) {
2134 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2135 SmallVector<int, 16> MaskAsInts;
2136 getShuffleMask(Mask, MaskAsInts);
2137 return isIdentityMask(MaskAsInts);
2138 }
2139
2140 /// Return true if this shuffle chooses elements from exactly one source
2141 /// vector without lane crossings and does not change the number of elements
2142 /// from its input vectors.
2143 /// Example: shufflevector <4 x n> A, <4 x n> B, <4,undef,6,undef>
2144 bool isIdentity() const {
2145 return !changesLength() && isIdentityMask(ShuffleMask);
2146 }
2147
2148 /// Return true if this shuffle lengthens exactly one source vector with
2149 /// undefs in the high elements.
2150 bool isIdentityWithPadding() const;
2151
2152 /// Return true if this shuffle extracts the first N elements of exactly one
2153 /// source vector.
2154 bool isIdentityWithExtract() const;
2155
2156 /// Return true if this shuffle concatenates its 2 source vectors. This
2157 /// returns false if either input is undefined. In that case, the shuffle is
2158 /// is better classified as an identity with padding operation.
2159 bool isConcat() const;
2160
2161 /// Return true if this shuffle mask chooses elements from its source vectors
2162 /// without lane crossings. A shuffle using this mask would be
2163 /// equivalent to a vector select with a constant condition operand.
2164 /// Example: <4,1,6,undef>
2165 /// This returns false if the mask does not choose from both input vectors.
2166 /// In that case, the shuffle is better classified as an identity shuffle.
2167 /// This assumes that vector operands are the same length as the mask
2168 /// (a length-changing shuffle can never be equivalent to a vector select).
2169 static bool isSelectMask(ArrayRef<int> Mask);
2170 static bool isSelectMask(const Constant *Mask) {
2171 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2172 SmallVector<int, 16> MaskAsInts;
2173 getShuffleMask(Mask, MaskAsInts);
2174 return isSelectMask(MaskAsInts);
2175 }
2176
2177 /// Return true if this shuffle chooses elements from its source vectors
2178 /// without lane crossings and all operands have the same number of elements.
2179 /// In other words, this shuffle is equivalent to a vector select with a
2180 /// constant condition operand.
2181 /// Example: shufflevector <4 x n> A, <4 x n> B, <undef,1,6,3>
2182 /// This returns false if the mask does not choose from both input vectors.
2183 /// In that case, the shuffle is better classified as an identity shuffle.
2184 /// TODO: Optionally allow length-changing shuffles.
2185 bool isSelect() const {
2186 return !changesLength() && isSelectMask(ShuffleMask);
2187 }
2188
2189 /// Return true if this shuffle mask swaps the order of elements from exactly
2190 /// one source vector.
2191 /// Example: <7,6,undef,4>
2192 /// This assumes that vector operands are the same length as the mask.
2193 static bool isReverseMask(ArrayRef<int> Mask);
2194 static bool isReverseMask(const Constant *Mask) {
2195 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2196 SmallVector<int, 16> MaskAsInts;
2197 getShuffleMask(Mask, MaskAsInts);
2198 return isReverseMask(MaskAsInts);
2199 }
2200
2201 /// Return true if this shuffle swaps the order of elements from exactly
2202 /// one source vector.
2203 /// Example: shufflevector <4 x n> A, <4 x n> B, <3,undef,1,undef>
2204 /// TODO: Optionally allow length-changing shuffles.
2205 bool isReverse() const {
2206 return !changesLength() && isReverseMask(ShuffleMask);
2207 }
2208
2209 /// Return true if this shuffle mask chooses all elements with the same value
2210 /// as the first element of exactly one source vector.
2211 /// Example: <4,undef,undef,4>
2212 /// This assumes that vector operands are the same length as the mask.
2213 static bool isZeroEltSplatMask(ArrayRef<int> Mask);
2214 static bool isZeroEltSplatMask(const Constant *Mask) {
2215 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2216 SmallVector<int, 16> MaskAsInts;
2217 getShuffleMask(Mask, MaskAsInts);
2218 return isZeroEltSplatMask(MaskAsInts);
2219 }
2220
2221 /// Return true if all elements of this shuffle are the same value as the
2222 /// first element of exactly one source vector without changing the length
2223 /// of that vector.
2224 /// Example: shufflevector <4 x n> A, <4 x n> B, <undef,0,undef,0>
2225 /// TODO: Optionally allow length-changing shuffles.
2226 /// TODO: Optionally allow splats from other elements.
2227 bool isZeroEltSplat() const {
2228 return !changesLength() && isZeroEltSplatMask(ShuffleMask);
2229 }
2230
2231 /// Return true if this shuffle mask is a transpose mask.
2232 /// Transpose vector masks transpose a 2xn matrix. They read corresponding
2233 /// even- or odd-numbered vector elements from two n-dimensional source
2234 /// vectors and write each result into consecutive elements of an
2235 /// n-dimensional destination vector. Two shuffles are necessary to complete
2236 /// the transpose, one for the even elements and another for the odd elements.
2237 /// This description closely follows how the TRN1 and TRN2 AArch64
2238 /// instructions operate.
2239 ///
2240 /// For example, a simple 2x2 matrix can be transposed with:
2241 ///
2242 /// ; Original matrix
2243 /// m0 = < a, b >
2244 /// m1 = < c, d >
2245 ///
2246 /// ; Transposed matrix
2247 /// t0 = < a, c > = shufflevector m0, m1, < 0, 2 >
2248 /// t1 = < b, d > = shufflevector m0, m1, < 1, 3 >
2249 ///
2250 /// For matrices having greater than n columns, the resulting nx2 transposed
2251 /// matrix is stored in two result vectors such that one vector contains
2252 /// interleaved elements from all the even-numbered rows and the other vector
2253 /// contains interleaved elements from all the odd-numbered rows. For example,
2254 /// a 2x4 matrix can be transposed with:
2255 ///
2256 /// ; Original matrix
2257 /// m0 = < a, b, c, d >
2258 /// m1 = < e, f, g, h >
2259 ///
2260 /// ; Transposed matrix
2261 /// t0 = < a, e, c, g > = shufflevector m0, m1 < 0, 4, 2, 6 >
2262 /// t1 = < b, f, d, h > = shufflevector m0, m1 < 1, 5, 3, 7 >
2263 static bool isTransposeMask(ArrayRef<int> Mask);
2264 static bool isTransposeMask(const Constant *Mask) {
2265 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2266 SmallVector<int, 16> MaskAsInts;
2267 getShuffleMask(Mask, MaskAsInts);
2268 return isTransposeMask(MaskAsInts);
2269 }
2270
2271 /// Return true if this shuffle transposes the elements of its inputs without
2272 /// changing the length of the vectors. This operation may also be known as a
2273 /// merge or interleave. See the description for isTransposeMask() for the
2274 /// exact specification.
2275 /// Example: shufflevector <4 x n> A, <4 x n> B, <0,4,2,6>
2276 bool isTranspose() const {
2277 return !changesLength() && isTransposeMask(ShuffleMask);
2278 }
2279
2280 /// Return true if this shuffle mask is an extract subvector mask.
2281 /// A valid extract subvector mask returns a smaller vector from a single
2282 /// source operand. The base extraction index is returned as well.
2283 static bool isExtractSubvectorMask(ArrayRef<int> Mask, int NumSrcElts,
2284 int &Index);
2285 static bool isExtractSubvectorMask(const Constant *Mask, int NumSrcElts,
2286 int &Index) {
2287 assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((void)0);
2288 // Not possible to express a shuffle mask for a scalable vector for this
2289 // case.
2290 if (isa<ScalableVectorType>(Mask->getType()))
2291 return false;
2292 SmallVector<int, 16> MaskAsInts;
2293 getShuffleMask(Mask, MaskAsInts);
2294 return isExtractSubvectorMask(MaskAsInts, NumSrcElts, Index);
2295 }
2296
2297 /// Return true if this shuffle mask is an extract subvector mask.
2298 bool isExtractSubvectorMask(int &Index) const {
2299 // Not possible to express a shuffle mask for a scalable vector for this
2300 // case.
2301 if (isa<ScalableVectorType>(getType()))
2302 return false;
2303
2304 int NumSrcElts =
2305 cast<FixedVectorType>(Op<0>()->getType())->getNumElements();
2306 return isExtractSubvectorMask(ShuffleMask, NumSrcElts, Index);
2307 }
2308
2309 /// Change values in a shuffle permute mask assuming the two vector operands
2310 /// of length InVecNumElts have swapped position.
2311 static void commuteShuffleMask(MutableArrayRef<int> Mask,
2312 unsigned InVecNumElts) {
2313 for (int &Idx : Mask) {
2314 if (Idx == -1)
2315 continue;
2316 Idx = Idx < (int)InVecNumElts ? Idx + InVecNumElts : Idx - InVecNumElts;
2317 assert(Idx >= 0 && Idx < (int)InVecNumElts * 2 &&((void)0)
2318 "shufflevector mask index out of range")((void)0);
2319 }
2320 }
2321
2322 // Methods for support type inquiry through isa, cast, and dyn_cast:
2323 static bool classof(const Instruction *I) {
2324 return I->getOpcode() == Instruction::ShuffleVector;
2325 }
2326 static bool classof(const Value *V) {
2327 return isa<Instruction>(V) && classof(cast<Instruction>(V));
2328 }
2329};
2330
2331template <>
2332struct OperandTraits<ShuffleVectorInst>
2333 : public FixedNumOperandTraits<ShuffleVectorInst, 2> {};
2334
2335DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ShuffleVectorInst, Value)ShuffleVectorInst::op_iterator ShuffleVectorInst::op_begin() {
return OperandTraits<ShuffleVectorInst>::op_begin(this
); } ShuffleVectorInst::const_op_iterator ShuffleVectorInst::
op_begin() const { return OperandTraits<ShuffleVectorInst>
::op_begin(const_cast<ShuffleVectorInst*>(this)); } ShuffleVectorInst
::op_iterator ShuffleVectorInst::op_end() { return OperandTraits
<ShuffleVectorInst>::op_end(this); } ShuffleVectorInst::
const_op_iterator ShuffleVectorInst::op_end() const { return OperandTraits
<ShuffleVectorInst>::op_end(const_cast<ShuffleVectorInst
*>(this)); } Value *ShuffleVectorInst::getOperand(unsigned
i_nocapture) const { ((void)0); return cast_or_null<Value
>( OperandTraits<ShuffleVectorInst>::op_begin(const_cast
<ShuffleVectorInst*>(this))[i_nocapture].get()); } void
ShuffleVectorInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((void)0); OperandTraits<ShuffleVectorInst>::op_begin
(this)[i_nocapture] = Val_nocapture; } unsigned ShuffleVectorInst
::getNumOperands() const { return OperandTraits<ShuffleVectorInst
>::operands(this); } template <int Idx_nocapture> Use
&ShuffleVectorInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
ShuffleVectorInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }
2336
2337//===----------------------------------------------------------------------===//
2338// ExtractValueInst Class
2339//===----------------------------------------------------------------------===//
2340
2341/// This instruction extracts a struct member or array
2342/// element value from an aggregate value.
2343///
2344class ExtractValueInst : public UnaryInstruction {
2345 SmallVector<unsigned, 4> Indices;
2346
2347 ExtractValueInst(const ExtractValueInst &EVI);
2348
2349 /// Constructors - Create a extractvalue instruction with a base aggregate
2350 /// value and a list of indices. The first ctor can optionally insert before
2351 /// an existing instruction, the second appends the new instruction to the
2352 /// specified BasicBlock.
2353 inline ExtractValueInst(Value *Agg,
2354 ArrayRef<unsigned> Idxs,
2355 const Twine &NameStr,
2356 Instruction *InsertBefore);
2357 inline ExtractValueInst(Value *Agg,
2358 ArrayRef<unsigned> Idxs,
2359 const Twine &NameStr, BasicBlock *InsertAtEnd);
2360
2361 void init(ArrayRef<unsigned> Idxs, const Twine &NameStr);
2362
2363protected:
2364 // Note: Instruction needs to be a friend here to call cloneImpl.
2365 friend class Instruction;
2366
2367 ExtractValueInst *cloneImpl() const;
2368
2369public:
2370 static ExtractValueInst *Create(Value *Agg,
2371 ArrayRef<unsigned> Idxs,
2372 const Twine &NameStr = "",
2373 Instruction *InsertBefore = nullptr) {
2374 return new
2375 ExtractValueInst(Agg, Idxs, NameStr, InsertBefore);
2376 }
2377
2378 static ExtractValueInst *Create(Value *Agg,
2379 ArrayRef<unsigned> Idxs,
2380 const Twine &NameStr,
2381 BasicBlock *InsertAtEnd) {
2382 return new ExtractValueInst(Agg, Idxs, NameStr, InsertAtEnd);
2383 }
2384
2385 /// Returns the type of the element that would be extracted
2386 /// with an extractvalue instruction with the specified parameters.
2387 ///
2388 /// Null is returned if the indices are invalid for the specified type.
2389 static Type *getIndexedType(Type *Agg, ArrayRef<unsigned> Idxs);
2390
2391 using idx_iterator = const unsigned*;
2392
2393 inline idx_iterator idx_begin() const { return Indices.begin(); }
2394 inline idx_iterator idx_end() const { return Indices.end(); }
2395 inline iterator_range<idx_iterator> indices() const {
2396 return make_range(idx_begin(), idx_end());
2397 }
2398
2399 Value *getAggregateOperand() {
2400 return getOperand(0);
2401 }
2402 const Value *getAggregateOperand() const {
2403 return getOperand(0);
2404 }
2405 static unsigned getAggregateOperandIndex() {
2406 return 0U; // get index for modifying correct operand
2407 }
2408
2409 ArrayRef<unsigned> getIndices() const {
2410 return Indices;
2411 }
2412
2413 unsigned getNumIndices() const {
2414 return (unsigned)Indices.size();
2415 }
2416
2417 bool hasIndices() const {
2418 return true;
2419 }
2420
2421 // Methods for support type inquiry through isa, cast, and dyn_cast:
2422 static bool classof(const Instruction *I) {
2423 return I->getOpcode() == Instruction::ExtractValue;
2424 }
2425 static bool classof(const Value *V) {
2426 return isa<Instruction>(V) && classof(cast<Instruction>(V));
2427 }
2428};
2429
2430ExtractValueInst::ExtractValueInst(Value *Agg,
2431 ArrayRef<unsigned> Idxs,
2432 const Twine &NameStr,
2433 Instruction *InsertBefore)
2434 : UnaryInstruction(checkGEPType(getIndexedType(Agg->getType(), Idxs)),
2435 ExtractValue, Agg, InsertBefore) {
2436 init(Idxs, NameStr);
2437}
2438
2439ExtractValueInst::ExtractValueInst(Value *Agg,
2440 ArrayRef<unsigned> Idxs,
2441 const Twine &NameStr,
2442 BasicBlock *InsertAtEnd)
2443 : UnaryInstruction(checkGEPType(getIndexedType(Agg->getType(), Idxs)),
2444 ExtractValue, Agg, InsertAtEnd) {
2445 init(Idxs, NameStr);
2446}
2447
2448//===----------------------------------------------------------------------===//
2449// InsertValueInst Class
2450//===----------------------------------------------------------------------===//
2451
2452/// This instruction inserts a struct field of array element
2453/// value into an aggregate value.
2454///
2455class InsertValueInst : public Instruction {
2456 SmallVector<unsigned, 4> Indices;
2457
2458 InsertValueInst(const InsertValueInst &IVI);
2459
2460 /// Constructors - Create a insertvalue instruction with a base aggregate
2461 /// value, a value to insert, and a list of indices. The first ctor can
2462 /// optionally insert before an existing instruction, the second appends
2463 /// the new instruction to the specified BasicBlock.
2464 inline InsertValueInst(Value *Agg, Value *Val,
2465 ArrayRef<unsigned> Idxs,
2466 const Twine &NameStr,
2467 Instruction *InsertBefore);
2468 inline InsertValueInst(Value *Agg, Value *Val,
2469 ArrayRef<unsigned> Idxs,
2470 const Twine &NameStr, BasicBlock *InsertAtEnd);
2471
2472 /// Constructors - These two constructors are convenience methods because one
2473 /// and two index insertvalue instructions are so common.
2474 InsertValueInst(Value *Agg, Value *Val, unsigned Idx,
2475 const Twine &NameStr = "",
2476 Instruction *InsertBefore = nullptr);
2477 InsertValueInst(Value *Agg, Value *Val, unsigned Idx, const Twine &NameStr,
2478 BasicBlock *InsertAtEnd);
2479
2480 void init(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
2481 const Twine &NameStr);
2482
2483protected:
2484 // Note: Instruction needs to be a friend here to call cloneImpl.
2485 friend class Instruction;
2486
2487 InsertValueInst *cloneImpl() const;
2488
2489public:
2490 // allocate space for exactly two operands
2491 void *operator new(size_t S) { return User::operator new(S, 2); }
2492 void operator delete(void *Ptr) { User::operator delete(Ptr); }
2493
2494 static InsertValueInst *Create(Value *Agg, Value *Val,
2495 ArrayRef<unsigned> Idxs,
2496 const Twine &NameStr = "",
2497 Instruction *InsertBefore = nullptr) {
2498 return new InsertValueInst(Agg, Val, Idxs, NameStr, InsertBefore);
2499 }
2500
2501 static InsertValueInst *Create(Value *Agg, Value *Val,
2502 ArrayRef<unsigned> Idxs,
2503 const Twine &NameStr,
2504 BasicBlock *InsertAtEnd) {
2505 return new InsertValueInst(Agg, Val, Idxs, NameStr, InsertAtEnd);
2506 }
2507
2508 /// Transparently provide more efficient getOperand methods.
2509 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
2510
2511 using idx_iterator = const unsigned*;
2512
2513 inline idx_iterator idx_begin() const { return Indices.begin(); }
2514 inline idx_iterator idx_end() const { return Indices.end(); }
2515 inline iterator_range<idx_iterator> indices() const {
2516 return make_range(idx_begin(), idx_end());
2517 }
2518
2519 Value *getAggregateOperand() {
2520 return getOperand(0);
2521 }
2522 const Value *getAggregateOperand() const {
2523 return getOperand(0);
2524 }
2525 static unsigned getAggregateOperandIndex() {
2526 return 0U; // get index for modifying correct operand
2527 }
2528
2529 Value *getInsertedValueOperand() {
2530 return getOperand(1);
2531 }
2532 const Value *getInsertedValueOperand() const {
2533 return getOperand(1);
2534 }
2535 static unsigned getInsertedValueOperandIndex() {
2536 return 1U; // get index for modifying correct operand
2537 }
2538
2539 ArrayRef<unsigned> getIndices() const {
2540 return Indices;
2541 }
2542
2543 unsigned getNumIndices() const {
2544 return (unsigned)Indices.size();
2545 }
2546
2547 bool hasIndices() const {
2548 return true;
2549 }
2550
2551 // Methods for support type inquiry through isa, cast, and dyn_cast:
2552 static bool classof(const Instruction *I) {
2553 return I->getOpcode() == Instruction::InsertValue;
2554 }
2555 static bool classof(const Value *V) {
2556 return isa<Instruction>(V) && classof(cast<Instruction>(V));
2557 }
2558};
2559
2560template <>
2561struct OperandTraits<InsertValueInst> :
2562 public FixedNumOperandTraits<InsertValueInst, 2> {
2563};
2564
2565InsertValueInst::InsertValueInst(Value *Agg,
2566 Value *Val,
2567 ArrayRef<unsigned> Idxs,
2568 const Twine &NameStr,
2569 Instruction *InsertBefore)
2570 : Instruction(Agg->getType(), InsertValue,
2571 OperandTraits<InsertValueInst>::op_begin(this),
2572 2, InsertBefore) {
2573 init(Agg, Val, Idxs, NameStr);
2574}
2575
2576InsertValueInst::InsertValueInst(Value *Agg,
2577 Value *Val,
2578 ArrayRef<unsigned> Idxs,
2579 const Twine &NameStr,
2580 BasicBlock *InsertAtEnd)
2581 : Instruction(Agg->getType(), InsertValue,
2582 OperandTraits<InsertValueInst>::op_begin(this),
2583 2, InsertAtEnd) {
2584 init(Agg, Val, Idxs, NameStr);
2585}
2586
2587DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertValueInst, Value)InsertValueInst::op_iterator InsertValueInst::op_begin() { return
OperandTraits<InsertValueInst>::op_begin(this); } InsertValueInst
::const_op_iterator InsertValueInst::op_begin() const { return
OperandTraits<InsertValueInst>::op_begin(const_cast<
InsertValueInst*>(this)); } InsertValueInst::op_iterator InsertValueInst
::op_end() { return OperandTraits<InsertValueInst>::op_end
(this); } InsertValueInst::const_op_iterator InsertValueInst::
op_end() const { return OperandTraits<InsertValueInst>::
op_end(const_cast<InsertValueInst*>(this)); } Value *InsertValueInst
::getOperand(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<InsertValueInst>::op_begin
(const_cast<InsertValueInst*>(this))[i_nocapture].get()
); } void InsertValueInst::setOperand(unsigned i_nocapture, Value
*Val_nocapture) { ((void)0); OperandTraits<InsertValueInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
InsertValueInst::getNumOperands() const { return OperandTraits
<InsertValueInst>::operands(this); } template <int Idx_nocapture
> Use &InsertValueInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
const Use &InsertValueInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }
2588
2589//===----------------------------------------------------------------------===//
2590// PHINode Class
2591//===----------------------------------------------------------------------===//
2592
2593// PHINode - The PHINode class is used to represent the magical mystical PHI
2594// node, that can not exist in nature, but can be synthesized in a computer
2595// scientist's overactive imagination.
2596//
2597class PHINode : public Instruction {
2598 /// The number of operands actually allocated. NumOperands is
2599 /// the number actually in use.
2600 unsigned ReservedSpace;
2601
2602 PHINode(const PHINode &PN);
2603
2604 explicit PHINode(Type *Ty, unsigned NumReservedValues,
2605 const Twine &NameStr = "",
2606 Instruction *InsertBefore = nullptr)
2607 : Instruction(Ty, Instruction::PHI, nullptr, 0, InsertBefore),
2608 ReservedSpace(NumReservedValues) {
2609 assert(!Ty->isTokenTy() && "PHI nodes cannot have token type!")((void)0);
2610 setName(NameStr);
2611 allocHungoffUses(ReservedSpace);
2612 }
2613
2614 PHINode(Type *Ty, unsigned NumReservedValues, const Twine &NameStr,
2615 BasicBlock *InsertAtEnd)
2616 : Instruction(Ty, Instruction::PHI, nullptr, 0, InsertAtEnd),
2617 ReservedSpace(NumReservedValues) {
2618 assert(!Ty->isTokenTy() && "PHI nodes cannot have token type!")((void)0);
2619 setName(NameStr);
2620 allocHungoffUses(ReservedSpace);
2621 }
2622
2623protected:
2624 // Note: Instruction needs to be a friend here to call cloneImpl.
2625 friend class Instruction;
2626
2627 PHINode *cloneImpl() const;
2628
2629 // allocHungoffUses - this is more complicated than the generic
2630 // User::allocHungoffUses, because we have to allocate Uses for the incoming
2631 // values and pointers to the incoming blocks, all in one allocation.
2632 void allocHungoffUses(unsigned N) {
2633 User::allocHungoffUses(N, /* IsPhi */ true);
2634 }
2635
2636public:
2637 /// Constructors - NumReservedValues is a hint for the number of incoming
2638 /// edges that this phi node will have (use 0 if you really have no idea).
2639 static PHINode *Create(Type *Ty, unsigned NumReservedValues,
2640 const Twine &NameStr = "",
2641 Instruction *InsertBefore = nullptr) {
2642 return new PHINode(Ty, NumReservedValues, NameStr, InsertBefore);
2643 }
2644
2645 static PHINode *Create(Type *Ty, unsigned NumReservedValues,
2646 const Twine &NameStr, BasicBlock *InsertAtEnd) {
2647 return new PHINode(Ty, NumReservedValues, NameStr, InsertAtEnd);
2648 }
2649
2650 /// Provide fast operand accessors
2651 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
2652
2653 // Block iterator interface. This provides access to the list of incoming
2654 // basic blocks, which parallels the list of incoming values.
2655
2656 using block_iterator = BasicBlock **;
2657 using const_block_iterator = BasicBlock * const *;
2658
2659 block_iterator block_begin() {
2660 return reinterpret_cast<block_iterator>(op_begin() + ReservedSpace);
2661 }
2662
2663 const_block_iterator block_begin() const {
2664 return reinterpret_cast<const_block_iterator>(op_begin() + ReservedSpace);
2665 }
2666
2667 block_iterator block_end() {
2668 return block_begin() + getNumOperands();
2669 }
2670
2671 const_block_iterator block_end() const {
2672 return block_begin() + getNumOperands();
2673 }
2674
2675 iterator_range<block_iterator> blocks() {
2676 return make_range(block_begin(), block_end());
2677 }
2678
2679 iterator_range<const_block_iterator> blocks() const {
2680 return make_range(block_begin(), block_end());
2681 }
2682
2683 op_range incoming_values() { return operands(); }
2684
2685 const_op_range incoming_values() const { return operands(); }
2686
2687 /// Return the number of incoming edges
2688 ///
2689 unsigned getNumIncomingValues() const { return getNumOperands(); }
2690
2691 /// Return incoming value number x
2692 ///
2693 Value *getIncomingValue(unsigned i) const {
2694 return getOperand(i);
2695 }
2696 void setIncomingValue(unsigned i, Value *V) {
2697 assert(V && "PHI node got a null value!")((void)0);
2698 assert(getType() == V->getType() &&((void)0)
2699 "All operands to PHI node must be the same type as the PHI node!")((void)0);
2700 setOperand(i, V);
2701 }
2702
2703 static unsigned getOperandNumForIncomingValue(unsigned i) {
2704 return i;
2705 }
2706
2707 static unsigned getIncomingValueNumForOperand(unsigned i) {
2708 return i;
2709 }
2710
2711 /// Return incoming basic block number @p i.
2712 ///
2713 BasicBlock *getIncomingBlock(unsigned i) const {
2714 return block_begin()[i];
2715 }
2716
2717 /// Return incoming basic block corresponding
2718 /// to an operand of the PHI.
2719 ///
2720 BasicBlock *getIncomingBlock(const Use &U) const {
2721 assert(this == U.getUser() && "Iterator doesn't point to PHI's Uses?")((void)0);
2722 return getIncomingBlock(unsigned(&U - op_begin()));
2723 }
2724
2725 /// Return incoming basic block corresponding
2726 /// to value use iterator.
2727 ///
2728 BasicBlock *getIncomingBlock(Value::const_user_iterator I) const {
2729 return getIncomingBlock(I.getUse());
2730 }
2731
2732 void setIncomingBlock(unsigned i, BasicBlock *BB) {
2733 assert(BB && "PHI node got a null basic block!")((void)0);
2734 block_begin()[i] = BB;
2735 }
2736
2737 /// Replace every incoming basic block \p Old to basic block \p New.
2738 void replaceIncomingBlockWith(const BasicBlock *Old, BasicBlock *New) {
2739 assert(New && Old && "PHI node got a null basic block!")((void)0);
2740 for (unsigned Op = 0, NumOps = getNumOperands(); Op != NumOps; ++Op)
2741 if (getIncomingBlock(Op) == Old)
2742 setIncomingBlock(Op, New);
2743 }
2744
2745 /// Add an incoming value to the end of the PHI list
2746 ///
2747 void addIncoming(Value *V, BasicBlock *BB) {
2748 if (getNumOperands() == ReservedSpace)
2749 growOperands(); // Get more space!
2750 // Initialize some new operands.
2751 setNumHungOffUseOperands(getNumOperands() + 1);
2752 setIncomingValue(getNumOperands() - 1, V);
2753 setIncomingBlock(getNumOperands() - 1, BB);
2754 }
2755
2756 /// Remove an incoming value. This is useful if a
2757 /// predecessor basic block is deleted. The value removed is returned.
2758 ///
2759 /// If the last incoming value for a PHI node is removed (and DeletePHIIfEmpty
2760 /// is true), the PHI node is destroyed and any uses of it are replaced with
2761 /// dummy values. The only time there should be zero incoming values to a PHI
2762 /// node is when the block is dead, so this strategy is sound.
2763 ///
2764 Value *removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty = true);
2765
2766 Value *removeIncomingValue(const BasicBlock *BB, bool DeletePHIIfEmpty=true) {
2767 int Idx = getBasicBlockIndex(BB);
2768 assert(Idx >= 0 && "Invalid basic block argument to remove!")((void)0);
2769 return removeIncomingValue(Idx, DeletePHIIfEmpty);
2770 }
2771
2772 /// Return the first index of the specified basic
2773 /// block in the value list for this PHI. Returns -1 if no instance.
2774 ///
2775 int getBasicBlockIndex(const BasicBlock *BB) const {
2776 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
2777 if (block_begin()[i] == BB)
2778 return i;
2779 return -1;
2780 }
2781
2782 Value *getIncomingValueForBlock(const BasicBlock *BB) const {
2783 int Idx = getBasicBlockIndex(BB);
2784 assert(Idx >= 0 && "Invalid basic block argument!")((void)0);
2785 return getIncomingValue(Idx);
2786 }
2787
2788 /// Set every incoming value(s) for block \p BB to \p V.
2789 void setIncomingValueForBlock(const BasicBlock *BB, Value *V) {
2790 assert(BB && "PHI node got a null basic block!")((void)0);
2791 bool Found = false;
2792 for (unsigned Op = 0, NumOps = getNumOperands(); Op != NumOps; ++Op)
2793 if (getIncomingBlock(Op) == BB) {
2794 Found = true;
2795 setIncomingValue(Op, V);
2796 }
2797 (void)Found;
2798 assert(Found && "Invalid basic block argument to set!")((void)0);
2799 }
2800
2801 /// If the specified PHI node always merges together the
2802 /// same value, return the value, otherwise return null.
2803 Value *hasConstantValue() const;
2804
2805 /// Whether the specified PHI node always merges
2806 /// together the same value, assuming undefs are equal to a unique
2807 /// non-undef value.
2808 bool hasConstantOrUndefValue() const;
2809
2810 /// If the PHI node is complete which means all of its parent's predecessors
2811 /// have incoming value in this PHI, return true, otherwise return false.
2812 bool isComplete() const {
2813 return llvm::all_of(predecessors(getParent()),
2814 [this](const BasicBlock *Pred) {
2815 return getBasicBlockIndex(Pred) >= 0;
2816 });
2817 }
2818
2819 /// Methods for support type inquiry through isa, cast, and dyn_cast:
2820 static bool classof(const Instruction *I) {
2821 return I->getOpcode() == Instruction::PHI;
2822 }
2823 static bool classof(const Value *V) {
2824 return isa<Instruction>(V) && classof(cast<Instruction>(V));
2825 }
2826
2827private:
2828 void growOperands();
2829};
2830
2831template <>
2832struct OperandTraits<PHINode> : public HungoffOperandTraits<2> {
2833};
2834
2835DEFINE_TRANSPARENT_OPERAND_ACCESSORS(PHINode, Value)PHINode::op_iterator PHINode::op_begin() { return OperandTraits
<PHINode>::op_begin(this); } PHINode::const_op_iterator
PHINode::op_begin() const { return OperandTraits<PHINode>
::op_begin(const_cast<PHINode*>(this)); } PHINode::op_iterator
PHINode::op_end() { return OperandTraits<PHINode>::op_end
(this); } PHINode::const_op_iterator PHINode::op_end() const {
return OperandTraits<PHINode>::op_end(const_cast<PHINode
*>(this)); } Value *PHINode::getOperand(unsigned i_nocapture
) const { ((void)0); return cast_or_null<Value>( OperandTraits
<PHINode>::op_begin(const_cast<PHINode*>(this))[i_nocapture
].get()); } void PHINode::setOperand(unsigned i_nocapture, Value
*Val_nocapture) { ((void)0); OperandTraits<PHINode>::op_begin
(this)[i_nocapture] = Val_nocapture; } unsigned PHINode::getNumOperands
() const { return OperandTraits<PHINode>::operands(this
); } template <int Idx_nocapture> Use &PHINode::Op(
) { return this->OpFrom<Idx_nocapture>(this); } template
<int Idx_nocapture> const Use &PHINode::Op() const
{ return this->OpFrom<Idx_nocapture>(this); }
2836
2837//===----------------------------------------------------------------------===//
2838// LandingPadInst Class
2839//===----------------------------------------------------------------------===//
2840
2841//===---------------------------------------------------------------------------
2842/// The landingpad instruction holds all of the information
2843/// necessary to generate correct exception handling. The landingpad instruction
2844/// cannot be moved from the top of a landing pad block, which itself is
2845/// accessible only from the 'unwind' edge of an invoke. This uses the
2846/// SubclassData field in Value to store whether or not the landingpad is a
2847/// cleanup.
2848///
2849class LandingPadInst : public Instruction {
2850 using CleanupField = BoolBitfieldElementT<0>;
2851
2852 /// The number of operands actually allocated. NumOperands is
2853 /// the number actually in use.
2854 unsigned ReservedSpace;
2855
2856 LandingPadInst(const LandingPadInst &LP);
2857
2858public:
2859 enum ClauseType { Catch, Filter };
2860
2861private:
2862 explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
2863 const Twine &NameStr, Instruction *InsertBefore);
2864 explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
2865 const Twine &NameStr, BasicBlock *InsertAtEnd);
2866
2867 // Allocate space for exactly zero operands.
2868 void *operator new(size_t S) { return User::operator new(S); }
2869
2870 void growOperands(unsigned Size);
2871 void init(unsigned NumReservedValues, const Twine &NameStr);
2872
2873protected:
2874 // Note: Instruction needs to be a friend here to call cloneImpl.
2875 friend class Instruction;
2876
2877 LandingPadInst *cloneImpl() const;
2878
2879public:
2880 void operator delete(void *Ptr) { User::operator delete(Ptr); }
2881
2882 /// Constructors - NumReservedClauses is a hint for the number of incoming
2883 /// clauses that this landingpad will have (use 0 if you really have no idea).
2884 static LandingPadInst *Create(Type *RetTy, unsigned NumReservedClauses,
2885 const Twine &NameStr = "",
2886 Instruction *InsertBefore = nullptr);
2887 static LandingPadInst *Create(Type *RetTy, unsigned NumReservedClauses,
2888 const Twine &NameStr, BasicBlock *InsertAtEnd);
2889
2890 /// Provide fast operand accessors
2891 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
2892
2893 /// Return 'true' if this landingpad instruction is a
2894 /// cleanup. I.e., it should be run when unwinding even if its landing pad
2895 /// doesn't catch the exception.
2896 bool isCleanup() const { return getSubclassData<CleanupField>(); }
2897
2898 /// Indicate that this landingpad instruction is a cleanup.
2899 void setCleanup(bool V) { setSubclassData<CleanupField>(V); }
2900
2901 /// Add a catch or filter clause to the landing pad.
2902 void addClause(Constant *ClauseVal);
2903
2904 /// Get the value of the clause at index Idx. Use isCatch/isFilter to
2905 /// determine what type of clause this is.
2906 Constant *getClause(unsigned Idx) const {
2907 return cast<Constant>(getOperandList()[Idx]);
2908 }
2909
2910 /// Return 'true' if the clause and index Idx is a catch clause.
2911 bool isCatch(unsigned Idx) const {
2912 return !isa<ArrayType>(getOperandList()[Idx]->getType());
2913 }
2914
2915 /// Return 'true' if the clause and index Idx is a filter clause.
2916 bool isFilter(unsigned Idx) const {
2917 return isa<ArrayType>(getOperandList()[Idx]->getType());
2918 }
2919
2920 /// Get the number of clauses for this landing pad.
2921 unsigned getNumClauses() const { return getNumOperands(); }
2922
2923 /// Grow the size of the operand list to accommodate the new
2924 /// number of clauses.
2925 void reserveClauses(unsigned Size) { growOperands(Size); }
2926
2927 // Methods for support type inquiry through isa, cast, and dyn_cast:
2928 static bool classof(const Instruction *I) {
2929 return I->getOpcode() == Instruction::LandingPad;
2930 }
2931 static bool classof(const Value *V) {
2932 return isa<Instruction>(V) && classof(cast<Instruction>(V));
2933 }
2934};
2935
2936template <>
2937struct OperandTraits<LandingPadInst> : public HungoffOperandTraits<1> {
2938};
2939
2940DEFINE_TRANSPARENT_OPERAND_ACCESSORS(LandingPadInst, Value)LandingPadInst::op_iterator LandingPadInst::op_begin() { return
OperandTraits<LandingPadInst>::op_begin(this); } LandingPadInst
::const_op_iterator LandingPadInst::op_begin() const { return
OperandTraits<LandingPadInst>::op_begin(const_cast<
LandingPadInst*>(this)); } LandingPadInst::op_iterator LandingPadInst
::op_end() { return OperandTraits<LandingPadInst>::op_end
(this); } LandingPadInst::const_op_iterator LandingPadInst::op_end
() const { return OperandTraits<LandingPadInst>::op_end
(const_cast<LandingPadInst*>(this)); } Value *LandingPadInst
::getOperand(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<LandingPadInst>::op_begin(
const_cast<LandingPadInst*>(this))[i_nocapture].get());
} void LandingPadInst::setOperand(unsigned i_nocapture, Value
*Val_nocapture) { ((void)0); OperandTraits<LandingPadInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
LandingPadInst::getNumOperands() const { return OperandTraits
<LandingPadInst>::operands(this); } template <int Idx_nocapture
> Use &LandingPadInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
const Use &LandingPadInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }
2941
2942//===----------------------------------------------------------------------===//
2943// ReturnInst Class
2944//===----------------------------------------------------------------------===//
2945
2946//===---------------------------------------------------------------------------
2947/// Return a value (possibly void), from a function. Execution
2948/// does not continue in this function any longer.
2949///
2950class ReturnInst : public Instruction {
2951 ReturnInst(const ReturnInst &RI);
2952
2953private:
2954 // ReturnInst constructors:
2955 // ReturnInst() - 'ret void' instruction
2956 // ReturnInst( null) - 'ret void' instruction
2957 // ReturnInst(Value* X) - 'ret X' instruction
2958 // ReturnInst( null, Inst *I) - 'ret void' instruction, insert before I
2959 // ReturnInst(Value* X, Inst *I) - 'ret X' instruction, insert before I
2960 // ReturnInst( null, BB *B) - 'ret void' instruction, insert @ end of B
2961 // ReturnInst(Value* X, BB *B) - 'ret X' instruction, insert @ end of B
2962 //
2963 // NOTE: If the Value* passed is of type void then the constructor behaves as
2964 // if it was passed NULL.
2965 explicit ReturnInst(LLVMContext &C, Value *retVal = nullptr,
2966 Instruction *InsertBefore = nullptr);
2967 ReturnInst(LLVMContext &C, Value *retVal, BasicBlock *InsertAtEnd);
2968 explicit ReturnInst(LLVMContext &C, BasicBlock *InsertAtEnd);
2969
2970protected:
2971 // Note: Instruction needs to be a friend here to call cloneImpl.
2972 friend class Instruction;
2973
2974 ReturnInst *cloneImpl() const;
2975
2976public:
2977 static ReturnInst* Create(LLVMContext &C, Value *retVal = nullptr,
2978 Instruction *InsertBefore = nullptr) {
2979 return new(!!retVal) ReturnInst(C, retVal, InsertBefore);
2980 }
2981
2982 static ReturnInst* Create(LLVMContext &C, Value *retVal,
2983 BasicBlock *InsertAtEnd) {
2984 return new(!!retVal) ReturnInst(C, retVal, InsertAtEnd);
2985 }
2986
2987 static ReturnInst* Create(LLVMContext &C, BasicBlock *InsertAtEnd) {
2988 return new(0) ReturnInst(C, InsertAtEnd);
2989 }
2990
2991 /// Provide fast operand accessors
2992 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
2993
2994 /// Convenience accessor. Returns null if there is no return value.
2995 Value *getReturnValue() const {
2996 return getNumOperands() != 0 ? getOperand(0) : nullptr;
2997 }
2998
2999 unsigned getNumSuccessors() const { return 0; }
3000
3001 // Methods for support type inquiry through isa, cast, and dyn_cast:
3002 static bool classof(const Instruction *I) {
3003 return (I->getOpcode() == Instruction::Ret);
3004 }
3005 static bool classof(const Value *V) {
3006 return isa<Instruction>(V) && classof(cast<Instruction>(V));
3007 }
3008
3009private:
3010 BasicBlock *getSuccessor(unsigned idx) const {
3011 llvm_unreachable("ReturnInst has no successors!")__builtin_unreachable();
3012 }
3013
3014 void setSuccessor(unsigned idx, BasicBlock *B) {
3015 llvm_unreachable("ReturnInst has no successors!")__builtin_unreachable();
3016 }
3017};
3018
3019template <>
3020struct OperandTraits<ReturnInst> : public VariadicOperandTraits<ReturnInst> {
3021};
3022
3023DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ReturnInst, Value)ReturnInst::op_iterator ReturnInst::op_begin() { return OperandTraits
<ReturnInst>::op_begin(this); } ReturnInst::const_op_iterator
ReturnInst::op_begin() const { return OperandTraits<ReturnInst
>::op_begin(const_cast<ReturnInst*>(this)); } ReturnInst
::op_iterator ReturnInst::op_end() { return OperandTraits<
ReturnInst>::op_end(this); } ReturnInst::const_op_iterator
ReturnInst::op_end() const { return OperandTraits<ReturnInst
>::op_end(const_cast<ReturnInst*>(this)); } Value *ReturnInst
::getOperand(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<ReturnInst>::op_begin(const_cast
<ReturnInst*>(this))[i_nocapture].get()); } void ReturnInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
void)0); OperandTraits<ReturnInst>::op_begin(this)[i_nocapture
] = Val_nocapture; } unsigned ReturnInst::getNumOperands() const
{ return OperandTraits<ReturnInst>::operands(this); } template
<int Idx_nocapture> Use &ReturnInst::Op() { return
this->OpFrom<Idx_nocapture>(this); } template <int
Idx_nocapture> const Use &ReturnInst::Op() const { return
this->OpFrom<Idx_nocapture>(this); }
3024
3025//===----------------------------------------------------------------------===//
3026// BranchInst Class
3027//===----------------------------------------------------------------------===//
3028
3029//===---------------------------------------------------------------------------
3030/// Conditional or Unconditional Branch instruction.
3031///
3032class BranchInst : public Instruction {
3033 /// Ops list - Branches are strange. The operands are ordered:
3034 /// [Cond, FalseDest,] TrueDest. This makes some accessors faster because
3035 /// they don't have to check for cond/uncond branchness. These are mostly
3036 /// accessed relative from op_end().
3037 BranchInst(const BranchInst &BI);
3038 // BranchInst constructors (where {B, T, F} are blocks, and C is a condition):
3039 // BranchInst(BB *B) - 'br B'
3040 // BranchInst(BB* T, BB *F, Value *C) - 'br C, T, F'
3041 // BranchInst(BB* B, Inst *I) - 'br B' insert before I
3042 // BranchInst(BB* T, BB *F, Value *C, Inst *I) - 'br C, T, F', insert before I
3043 // BranchInst(BB* B, BB *I) - 'br B' insert at end
3044 // BranchInst(BB* T, BB *F, Value *C, BB *I) - 'br C, T, F', insert at end
3045 explicit BranchInst(BasicBlock *IfTrue, Instruction *InsertBefore = nullptr);
3046 BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
3047 Instruction *InsertBefore = nullptr);
3048 BranchInst(BasicBlock *IfTrue, BasicBlock *InsertAtEnd);
3049 BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
3050 BasicBlock *InsertAtEnd);
3051
3052 void AssertOK();
3053
3054protected:
3055 // Note: Instruction needs to be a friend here to call cloneImpl.
3056 friend class Instruction;
3057
3058 BranchInst *cloneImpl() const;
3059
3060public:
3061 /// Iterator type that casts an operand to a basic block.
3062 ///
3063 /// This only makes sense because the successors are stored as adjacent
3064 /// operands for branch instructions.
3065 struct succ_op_iterator
3066 : iterator_adaptor_base<succ_op_iterator, value_op_iterator,
3067 std::random_access_iterator_tag, BasicBlock *,
3068 ptrdiff_t, BasicBlock *, BasicBlock *> {
3069 explicit succ_op_iterator(value_op_iterator I) : iterator_adaptor_base(I) {}
3070
3071 BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
3072 BasicBlock *operator->() const { return operator*(); }
3073 };
3074
3075 /// The const version of `succ_op_iterator`.
3076 struct const_succ_op_iterator
3077 : iterator_adaptor_base<const_succ_op_iterator, const_value_op_iterator,
3078 std::random_access_iterator_tag,
3079 const BasicBlock *, ptrdiff_t, const BasicBlock *,
3080 const BasicBlock *> {
3081 explicit const_succ_op_iterator(const_value_op_iterator I)
3082 : iterator_adaptor_base(I) {}
3083
3084 const BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
3085 const BasicBlock *operator->() const { return operator*(); }
3086 };
3087
3088 static BranchInst *Create(BasicBlock *IfTrue,
3089 Instruction *InsertBefore = nullptr) {
3090 return new(1) BranchInst(IfTrue, InsertBefore);
3091 }
3092
3093 static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *IfFalse,
3094 Value *Cond, Instruction *InsertBefore = nullptr) {
3095 return new(3) BranchInst(IfTrue, IfFalse, Cond, InsertBefore);
3096 }
3097
3098 static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *InsertAtEnd) {
3099 return new(1) BranchInst(IfTrue, InsertAtEnd);
3100 }
3101
3102 static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *IfFalse,
3103 Value *Cond, BasicBlock *InsertAtEnd) {
3104 return new(3) BranchInst(IfTrue, IfFalse, Cond, InsertAtEnd);
3105 }
3106
3107 /// Transparently provide more efficient getOperand methods.
3108 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
setOperand(unsigned, Value*); inline op_iterator op_begin();
inline const_op_iterator op_begin() const; inline op_iterator
op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
getNumOperands() const
;
3109
3110 bool isUnconditional() const { return getNumOperands() == 1; }
3111 bool isConditional() const { return getNumOperands() == 3; }
3112
3113 Value *getCondition() const {
3114 assert(isConditional() && "Cannot get condition of an uncond branch!")((void)0);
3115 return Op<-3>();
3116 }
3117
3118 void setCondition(Value *V) {
3119 assert(isConditional() && "Cannot set condition of unconditional branch!")((void)0);
3120 Op<-3>() = V;
3121 }
3122
3123 unsigned getNumSuccessors() const { return 1+isConditional(); }
3124
3125 BasicBlock *getSuccessor(unsigned i) const {
3126 assert(i < getNumSuccessors() && "Successor # out of range for Branch!")((void)0);
3127 return cast_or_null<BasicBlock>((&Op<-1>() - i)->get());
3128 }
3129
3130 void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
3131 assert(idx < getNumSuccessors() && "Successor # out of range for Branch!")((void)0);
3132 *(&Op<-1>() - idx) = NewSucc;
3133 }
3134
3135 /// Swap the successors of this branch instruction.
3136 ///
3137 /// Swaps the successors of the branch instruction. This also swaps any
3138 /// branch weight metadata associated with the instruction so that it
3139 /// continues to map correctly to each operand.
3140 void swapSuccessors();
3141
3142 iterator_range<succ_op_iterator> successors() {
3143 return make_range(
3144 succ_op_iterator(std::next(value_op_begin(), isConditional() ? 1 : 0)),
3145 succ_op_iterator(value_op_end()));
3146 }
3147
3148 iterator_range<const_succ_op_iterator> successors() const {
3149 return make_range(const_succ_op_iterator(
3150 std::next(value_op_begin(), isConditional() ? 1 : 0)),
3151 const_succ_op_iterator(value_op_end()));
3152 }
3153
3154 // Methods for support type inquiry through isa, cast, and dyn_cast:
3155 static bool classof(const Instruction *I) {
3156 return (I->getOpcode() == Instruction::Br);
3157 }
3158 static bool classof(const Value *V) {
3159 return isa<Instruction>(V) && classof(cast<Instruction>(V));
3160 }
3161};
3162
3163template <>
3164struct OperandTraits<BranchInst> : public VariadicOperandTraits<BranchInst, 1> {
3165};
3166
3167DEFINE_TRANSPARENT_OPERAND_ACCESSORS(BranchInst, Value)BranchInst::op_iterato