Bug Summary

File:src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/CodeGen/SelectionDAGNodes.h
Warning:line 1150, column 10
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 StatepointLowering.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 static -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" -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 -stack-protector 2 -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/CodeGen/SelectionDAG/StatepointLowering.cpp

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp

→
1//===- StatepointLowering.cpp - SDAGBuilder's statepoint code -------------===//
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 includes support code use by SelectionDAGBuilder when lowering a
10// statepoint sequence in SelectionDAG IR.
11//
12//===----------------------------------------------------------------------===//
13
14#include "StatepointLowering.h"
15#include "SelectionDAGBuilder.h"
16#include "llvm/ADT/ArrayRef.h"
17#include "llvm/ADT/None.h"
18#include "llvm/ADT/Optional.h"
19#include "llvm/ADT/STLExtras.h"
20#include "llvm/ADT/SmallSet.h"
21#include "llvm/ADT/Statistic.h"
22#include "llvm/CodeGen/FunctionLoweringInfo.h"
23#include "llvm/CodeGen/GCMetadata.h"
24#include "llvm/CodeGen/ISDOpcodes.h"
25#include "llvm/CodeGen/MachineFrameInfo.h"
26#include "llvm/CodeGen/MachineFunction.h"
27#include "llvm/CodeGen/MachineMemOperand.h"
28#include "llvm/CodeGen/RuntimeLibcalls.h"
29#include "llvm/CodeGen/SelectionDAG.h"
30#include "llvm/CodeGen/StackMaps.h"
31#include "llvm/CodeGen/TargetLowering.h"
32#include "llvm/CodeGen/TargetOpcodes.h"
33#include "llvm/IR/CallingConv.h"
34#include "llvm/IR/DerivedTypes.h"
35#include "llvm/IR/GCStrategy.h"
36#include "llvm/IR/Instruction.h"
37#include "llvm/IR/Instructions.h"
38#include "llvm/IR/LLVMContext.h"
39#include "llvm/IR/Statepoint.h"
40#include "llvm/IR/Type.h"
41#include "llvm/Support/Casting.h"
42#include "llvm/Support/CommandLine.h"
43#include "llvm/Support/MachineValueType.h"
44#include "llvm/Target/TargetMachine.h"
45#include "llvm/Target/TargetOptions.h"
46#include <cassert>
47#include <cstddef>
48#include <cstdint>
49#include <iterator>
50#include <tuple>
51#include <utility>
52
53using namespace llvm;
54
55#define DEBUG_TYPE"statepoint-lowering" "statepoint-lowering"
56
57STATISTIC(NumSlotsAllocatedForStatepoints,static llvm::Statistic NumSlotsAllocatedForStatepoints = {"statepoint-lowering"
, "NumSlotsAllocatedForStatepoints", "Number of stack slots allocated for statepoints"
}
58 "Number of stack slots allocated for statepoints")static llvm::Statistic NumSlotsAllocatedForStatepoints = {"statepoint-lowering"
, "NumSlotsAllocatedForStatepoints", "Number of stack slots allocated for statepoints"
};
59STATISTIC(NumOfStatepoints, "Number of statepoint nodes encountered")static llvm::Statistic NumOfStatepoints = {"statepoint-lowering"
, "NumOfStatepoints", "Number of statepoint nodes encountered"
};
60STATISTIC(StatepointMaxSlotsRequired,static llvm::Statistic StatepointMaxSlotsRequired = {"statepoint-lowering"
, "StatepointMaxSlotsRequired", "Maximum number of stack slots required for a singe statepoint"
}
61 "Maximum number of stack slots required for a singe statepoint")static llvm::Statistic StatepointMaxSlotsRequired = {"statepoint-lowering"
, "StatepointMaxSlotsRequired", "Maximum number of stack slots required for a singe statepoint"
};
62
63cl::opt<bool> UseRegistersForDeoptValues(
64 "use-registers-for-deopt-values", cl::Hidden, cl::init(false),
65 cl::desc("Allow using registers for non pointer deopt args"));
66
67cl::opt<bool> UseRegistersForGCPointersInLandingPad(
68 "use-registers-for-gc-values-in-landing-pad", cl::Hidden, cl::init(false),
69 cl::desc("Allow using registers for gc pointer in landing pad"));
70
71cl::opt<unsigned> MaxRegistersForGCPointers(
72 "max-registers-for-gc-values", cl::Hidden, cl::init(0),
73 cl::desc("Max number of VRegs allowed to pass GC pointer meta args in"));
74
75typedef FunctionLoweringInfo::StatepointRelocationRecord RecordType;
76
77static void pushStackMapConstant(SmallVectorImpl<SDValue>& Ops,
78 SelectionDAGBuilder &Builder, uint64_t Value) {
79 SDLoc L = Builder.getCurSDLoc();
80 Ops.push_back(Builder.DAG.getTargetConstant(StackMaps::ConstantOp, L,
81 MVT::i64));
82 Ops.push_back(Builder.DAG.getTargetConstant(Value, L, MVT::i64));
83}
84
85void StatepointLoweringState::startNewStatepoint(SelectionDAGBuilder &Builder) {
86 // Consistency check
87 assert(PendingGCRelocateCalls.empty() &&((void)0)
88 "Trying to visit statepoint before finished processing previous one")((void)0);
89 Locations.clear();
90 NextSlotToAllocate = 0;
91 // Need to resize this on each safepoint - we need the two to stay in sync and
92 // the clear patterns of a SelectionDAGBuilder have no relation to
93 // FunctionLoweringInfo. Also need to ensure used bits get cleared.
94 AllocatedStackSlots.clear();
95 AllocatedStackSlots.resize(Builder.FuncInfo.StatepointStackSlots.size());
96}
97
98void StatepointLoweringState::clear() {
99 Locations.clear();
100 AllocatedStackSlots.clear();
101 assert(PendingGCRelocateCalls.empty() &&((void)0)
102 "cleared before statepoint sequence completed")((void)0);
103}
104
105SDValue
106StatepointLoweringState::allocateStackSlot(EVT ValueType,
107 SelectionDAGBuilder &Builder) {
108 NumSlotsAllocatedForStatepoints++;
109 MachineFrameInfo &MFI = Builder.DAG.getMachineFunction().getFrameInfo();
110
111 unsigned SpillSize = ValueType.getStoreSize();
112 assert((SpillSize * 8) ==((void)0)
113 (-8u & (7 + ValueType.getSizeInBits())) && // Round up modulo 8.((void)0)
114 "Size not in bytes?")((void)0);
115
116 // First look for a previously created stack slot which is not in
117 // use (accounting for the fact arbitrary slots may already be
118 // reserved), or to create a new stack slot and use it.
119
120 const size_t NumSlots = AllocatedStackSlots.size();
121 assert(NextSlotToAllocate <= NumSlots && "Broken invariant")((void)0);
122
123 assert(AllocatedStackSlots.size() ==((void)0)
124 Builder.FuncInfo.StatepointStackSlots.size() &&((void)0)
125 "Broken invariant")((void)0);
126
127 for (; NextSlotToAllocate < NumSlots; NextSlotToAllocate++) {
128 if (!AllocatedStackSlots.test(NextSlotToAllocate)) {
129 const int FI = Builder.FuncInfo.StatepointStackSlots[NextSlotToAllocate];
130 if (MFI.getObjectSize(FI) == SpillSize) {
131 AllocatedStackSlots.set(NextSlotToAllocate);
132 // TODO: Is ValueType the right thing to use here?
133 return Builder.DAG.getFrameIndex(FI, ValueType);
134 }
135 }
136 }
137
138 // Couldn't find a free slot, so create a new one:
139
140 SDValue SpillSlot = Builder.DAG.CreateStackTemporary(ValueType);
141 const unsigned FI = cast<FrameIndexSDNode>(SpillSlot)->getIndex();
142 MFI.markAsStatepointSpillSlotObjectIndex(FI);
143
144 Builder.FuncInfo.StatepointStackSlots.push_back(FI);
145 AllocatedStackSlots.resize(AllocatedStackSlots.size()+1, true);
146 assert(AllocatedStackSlots.size() ==((void)0)
147 Builder.FuncInfo.StatepointStackSlots.size() &&((void)0)
148 "Broken invariant")((void)0);
149
150 StatepointMaxSlotsRequired.updateMax(
151 Builder.FuncInfo.StatepointStackSlots.size());
152
153 return SpillSlot;
154}
155
156/// Utility function for reservePreviousStackSlotForValue. Tries to find
157/// stack slot index to which we have spilled value for previous statepoints.
158/// LookUpDepth specifies maximum DFS depth this function is allowed to look.
159static Optional<int> findPreviousSpillSlot(const Value *Val,
160 SelectionDAGBuilder &Builder,
161 int LookUpDepth) {
162 // Can not look any further - give up now
163 if (LookUpDepth <= 0)
164 return None;
165
166 // Spill location is known for gc relocates
167 if (const auto *Relocate = dyn_cast<GCRelocateInst>(Val)) {
168 const auto &RelocationMap =
169 Builder.FuncInfo.StatepointRelocationMaps[Relocate->getStatepoint()];
170
171 auto It = RelocationMap.find(Relocate->getDerivedPtr());
172 if (It == RelocationMap.end())
173 return None;
174
175 auto &Record = It->second;
176 if (Record.type != RecordType::Spill)
177 return None;
178
179 return Record.payload.FI;
180 }
181
182 // Look through bitcast instructions.
183 if (const BitCastInst *Cast = dyn_cast<BitCastInst>(Val))
184 return findPreviousSpillSlot(Cast->getOperand(0), Builder, LookUpDepth - 1);
185
186 // Look through phi nodes
187 // All incoming values should have same known stack slot, otherwise result
188 // is unknown.
189 if (const PHINode *Phi = dyn_cast<PHINode>(Val)) {
190 Optional<int> MergedResult = None;
191
192 for (auto &IncomingValue : Phi->incoming_values()) {
193 Optional<int> SpillSlot =
194 findPreviousSpillSlot(IncomingValue, Builder, LookUpDepth - 1);
195 if (!SpillSlot.hasValue())
196 return None;
197
198 if (MergedResult.hasValue() && *MergedResult != *SpillSlot)
199 return None;
200
201 MergedResult = SpillSlot;
202 }
203 return MergedResult;
204 }
205
206 // TODO: We can do better for PHI nodes. In cases like this:
207 // ptr = phi(relocated_pointer, not_relocated_pointer)
208 // statepoint(ptr)
209 // We will return that stack slot for ptr is unknown. And later we might
210 // assign different stack slots for ptr and relocated_pointer. This limits
211 // llvm's ability to remove redundant stores.
212 // Unfortunately it's hard to accomplish in current infrastructure.
213 // We use this function to eliminate spill store completely, while
214 // in example we still need to emit store, but instead of any location
215 // we need to use special "preferred" location.
216
217 // TODO: handle simple updates. If a value is modified and the original
218 // value is no longer live, it would be nice to put the modified value in the
219 // same slot. This allows folding of the memory accesses for some
220 // instructions types (like an increment).
221 // statepoint (i)
222 // i1 = i+1
223 // statepoint (i1)
224 // However we need to be careful for cases like this:
225 // statepoint(i)
226 // i1 = i+1
227 // statepoint(i, i1)
228 // Here we want to reserve spill slot for 'i', but not for 'i+1'. If we just
229 // put handling of simple modifications in this function like it's done
230 // for bitcasts we might end up reserving i's slot for 'i+1' because order in
231 // which we visit values is unspecified.
232
233 // Don't know any information about this instruction
234 return None;
235}
236
237/// Return true if-and-only-if the given SDValue can be lowered as either a
238/// constant argument or a stack reference. The key point is that the value
239/// doesn't need to be spilled or tracked as a vreg use.
240static bool willLowerDirectly(SDValue Incoming) {
241 // We are making an unchecked assumption that the frame size <= 2^16 as that
242 // is the largest offset which can be encoded in the stackmap format.
243 if (isa<FrameIndexSDNode>(Incoming))
244 return true;
245
246 // The largest constant describeable in the StackMap format is 64 bits.
247 // Potential Optimization: Constants values are sign extended by consumer,
248 // and thus there are many constants of static type > 64 bits whose value
249 // happens to be sext(Con64) and could thus be lowered directly.
250 if (Incoming.getValueType().getSizeInBits() > 64)
251 return false;
252
253 return (isa<ConstantSDNode>(Incoming) || isa<ConstantFPSDNode>(Incoming) ||
254 Incoming.isUndef());
255}
256
257/// Try to find existing copies of the incoming values in stack slots used for
258/// statepoint spilling. If we can find a spill slot for the incoming value,
259/// mark that slot as allocated, and reuse the same slot for this safepoint.
260/// This helps to avoid series of loads and stores that only serve to reshuffle
261/// values on the stack between calls.
262static void reservePreviousStackSlotForValue(const Value *IncomingValue,
263 SelectionDAGBuilder &Builder) {
264 SDValue Incoming = Builder.getValue(IncomingValue);
265
266 // If we won't spill this, we don't need to check for previously allocated
267 // stack slots.
268 if (willLowerDirectly(Incoming))
269 return;
270
271 SDValue OldLocation = Builder.StatepointLowering.getLocation(Incoming);
272 if (OldLocation.getNode())
273 // Duplicates in input
274 return;
275
276 const int LookUpDepth = 6;
277 Optional<int> Index =
278 findPreviousSpillSlot(IncomingValue, Builder, LookUpDepth);
279 if (!Index.hasValue())
280 return;
281
282 const auto &StatepointSlots = Builder.FuncInfo.StatepointStackSlots;
283
284 auto SlotIt = find(StatepointSlots, *Index);
285 assert(SlotIt != StatepointSlots.end() &&((void)0)
286 "Value spilled to the unknown stack slot")((void)0);
287
288 // This is one of our dedicated lowering slots
289 const int Offset = std::distance(StatepointSlots.begin(), SlotIt);
290 if (Builder.StatepointLowering.isStackSlotAllocated(Offset)) {
291 // stack slot already assigned to someone else, can't use it!
292 // TODO: currently we reserve space for gc arguments after doing
293 // normal allocation for deopt arguments. We should reserve for
294 // _all_ deopt and gc arguments, then start allocating. This
295 // will prevent some moves being inserted when vm state changes,
296 // but gc state doesn't between two calls.
297 return;
298 }
299 // Reserve this stack slot
300 Builder.StatepointLowering.reserveStackSlot(Offset);
301
302 // Cache this slot so we find it when going through the normal
303 // assignment loop.
304 SDValue Loc =
305 Builder.DAG.getTargetFrameIndex(*Index, Builder.getFrameIndexTy());
306 Builder.StatepointLowering.setLocation(Incoming, Loc);
307}
308
309/// Extract call from statepoint, lower it and return pointer to the
310/// call node. Also update NodeMap so that getValue(statepoint) will
311/// reference lowered call result
312static std::pair<SDValue, SDNode *> lowerCallFromStatepointLoweringInfo(
313 SelectionDAGBuilder::StatepointLoweringInfo &SI,
314 SelectionDAGBuilder &Builder, SmallVectorImpl<SDValue> &PendingExports) {
315 SDValue ReturnValue, CallEndVal;
316 std::tie(ReturnValue, CallEndVal) =
317 Builder.lowerInvokable(SI.CLI, SI.EHPadBB);
318 SDNode *CallEnd = CallEndVal.getNode();
319
320 // Get a call instruction from the call sequence chain. Tail calls are not
321 // allowed. The following code is essentially reverse engineering X86's
322 // LowerCallTo.
323 //
324 // We are expecting DAG to have the following form:
325 //
326 // ch = eh_label (only in case of invoke statepoint)
327 // ch, glue = callseq_start ch
328 // ch, glue = X86::Call ch, glue
329 // ch, glue = callseq_end ch, glue
330 // get_return_value ch, glue
331 //
332 // get_return_value can either be a sequence of CopyFromReg instructions
333 // to grab the return value from the return register(s), or it can be a LOAD
334 // to load a value returned by reference via a stack slot.
335
336 bool HasDef = !SI.CLI.RetTy->isVoidTy();
337 if (HasDef) {
338 if (CallEnd->getOpcode() == ISD::LOAD)
339 CallEnd = CallEnd->getOperand(0).getNode();
340 else
341 while (CallEnd->getOpcode() == ISD::CopyFromReg)
342 CallEnd = CallEnd->getOperand(0).getNode();
343 }
344
345 assert(CallEnd->getOpcode() == ISD::CALLSEQ_END && "expected!")((void)0);
346 return std::make_pair(ReturnValue, CallEnd->getOperand(0).getNode());
347}
348
349static MachineMemOperand* getMachineMemOperand(MachineFunction &MF,
350 FrameIndexSDNode &FI) {
351 auto PtrInfo = MachinePointerInfo::getFixedStack(MF, FI.getIndex());
352 auto MMOFlags = MachineMemOperand::MOStore |
353 MachineMemOperand::MOLoad | MachineMemOperand::MOVolatile;
354 auto &MFI = MF.getFrameInfo();
355 return MF.getMachineMemOperand(PtrInfo, MMOFlags,
356 MFI.getObjectSize(FI.getIndex()),
357 MFI.getObjectAlign(FI.getIndex()));
358}
359
360/// Spill a value incoming to the statepoint. It might be either part of
361/// vmstate
362/// or gcstate. In both cases unconditionally spill it on the stack unless it
363/// is a null constant. Return pair with first element being frame index
364/// containing saved value and second element with outgoing chain from the
365/// emitted store
366static std::tuple<SDValue, SDValue, MachineMemOperand*>
367spillIncomingStatepointValue(SDValue Incoming, SDValue Chain,
368 SelectionDAGBuilder &Builder) {
369 SDValue Loc = Builder.StatepointLowering.getLocation(Incoming);
370 MachineMemOperand* MMO = nullptr;
371
372 // Emit new store if we didn't do it for this ptr before
373 if (!Loc.getNode()) {
374 Loc = Builder.StatepointLowering.allocateStackSlot(Incoming.getValueType(),
375 Builder);
376 int Index = cast<FrameIndexSDNode>(Loc)->getIndex();
377 // We use TargetFrameIndex so that isel will not select it into LEA
378 Loc = Builder.DAG.getTargetFrameIndex(Index, Builder.getFrameIndexTy());
379
380 // Right now we always allocate spill slots that are of the same
381 // size as the value we're about to spill (the size of spillee can
382 // vary since we spill vectors of pointers too). At some point we
383 // can consider allowing spills of smaller values to larger slots
384 // (i.e. change the '==' in the assert below to a '>=').
385 MachineFrameInfo &MFI = Builder.DAG.getMachineFunction().getFrameInfo();
386 assert((MFI.getObjectSize(Index) * 8) ==((void)0)
387 (-8 & (7 + // Round up modulo 8.((void)0)
388 (int64_t)Incoming.getValueSizeInBits())) &&((void)0)
389 "Bad spill: stack slot does not match!")((void)0);
390
391 // Note: Using the alignment of the spill slot (rather than the abi or
392 // preferred alignment) is required for correctness when dealing with spill
393 // slots with preferred alignments larger than frame alignment..
394 auto &MF = Builder.DAG.getMachineFunction();
395 auto PtrInfo = MachinePointerInfo::getFixedStack(MF, Index);
396 auto *StoreMMO = MF.getMachineMemOperand(
397 PtrInfo, MachineMemOperand::MOStore, MFI.getObjectSize(Index),
398 MFI.getObjectAlign(Index));
399 Chain = Builder.DAG.getStore(Chain, Builder.getCurSDLoc(), Incoming, Loc,
400 StoreMMO);
401
402 MMO = getMachineMemOperand(MF, *cast<FrameIndexSDNode>(Loc));
403
404 Builder.StatepointLowering.setLocation(Incoming, Loc);
405 }
406
407 assert(Loc.getNode())((void)0);
408 return std::make_tuple(Loc, Chain, MMO);
409}
410
411/// Lower a single value incoming to a statepoint node. This value can be
412/// either a deopt value or a gc value, the handling is the same. We special
413/// case constants and allocas, then fall back to spilling if required.
414static void
415lowerIncomingStatepointValue(SDValue Incoming, bool RequireSpillSlot,
416 SmallVectorImpl<SDValue> &Ops,
417 SmallVectorImpl<MachineMemOperand *> &MemRefs,
418 SelectionDAGBuilder &Builder) {
419
420 if (willLowerDirectly(Incoming)) {
24
←
Taking true branch
→
421 if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Incoming)) {
25
←
Calling 'dyn_cast<llvm::FrameIndexSDNode, llvm::SDValue>'
→
38
←
Returning from 'dyn_cast<llvm::FrameIndexSDNode, llvm::SDValue>'
→
39
←
Assuming 'FI' is null
→
40
←
Assuming pointer value is null
→
41
←
Taking false branch
→
422 // This handles allocas as arguments to the statepoint (this is only
423 // really meaningful for a deopt value. For GC, we'd be trying to
424 // relocate the address of the alloca itself?)
425 assert(Incoming.getValueType() == Builder.getFrameIndexTy() &&((void)0)
426 "Incoming value is a frame index!")((void)0);
427 Ops.push_back(Builder.DAG.getTargetFrameIndex(FI->getIndex(),
428 Builder.getFrameIndexTy()));
429
430 auto &MF = Builder.DAG.getMachineFunction();
431 auto *MMO = getMachineMemOperand(MF, *FI);
432 MemRefs.push_back(MMO);
433 return;
434 }
435
436 assert(Incoming.getValueType().getSizeInBits() <= 64)((void)0);
437
438 if (Incoming.isUndef()) {
42
←
Calling 'SDValue::isUndef'
→
439 // Put an easily recognized constant that's unlikely to be a valid
440 // value so that uses of undef by the consumer of the stackmap is
441 // easily recognized. This is legal since the compiler is always
442 // allowed to chose an arbitrary value for undef.
443 pushStackMapConstant(Ops, Builder, 0xFEFEFEFE);
444 return;
445 }
446
447 // If the original value was a constant, make sure it gets recorded as
448 // such in the stackmap. This is required so that the consumer can
449 // parse any internal format to the deopt state. It also handles null
450 // pointers and other constant pointers in GC states.
451 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Incoming)) {
452 pushStackMapConstant(Ops, Builder, C->getSExtValue());
453 return;
454 } else if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Incoming)) {
455 pushStackMapConstant(Ops, Builder,
456 C->getValueAPF().bitcastToAPInt().getZExtValue());
457 return;
458 }
459
460 llvm_unreachable("unhandled direct lowering case")__builtin_unreachable();
461 }
462
463
464
465 if (!RequireSpillSlot) {
466 // If this value is live in (not live-on-return, or live-through), we can
467 // treat it the same way patchpoint treats it's "live in" values. We'll
468 // end up folding some of these into stack references, but they'll be
469 // handled by the register allocator. Note that we do not have the notion
470 // of a late use so these values might be placed in registers which are
471 // clobbered by the call. This is fine for live-in. For live-through
472 // fix-up pass should be executed to force spilling of such registers.
473 Ops.push_back(Incoming);
474 } else {
475 // Otherwise, locate a spill slot and explicitly spill it so it can be
476 // found by the runtime later. Note: We know all of these spills are
477 // independent, but don't bother to exploit that chain wise. DAGCombine
478 // will happily do so as needed, so doing it here would be a small compile
479 // time win at most.
480 SDValue Chain = Builder.getRoot();
481 auto Res = spillIncomingStatepointValue(Incoming, Chain, Builder);
482 Ops.push_back(std::get<0>(Res));
483 if (auto *MMO = std::get<2>(Res))
484 MemRefs.push_back(MMO);
485 Chain = std::get<1>(Res);;
486 Builder.DAG.setRoot(Chain);
487 }
488
489}
490
491/// Return true if value V represents the GC value. The behavior is conservative
492/// in case it is not sure that value is not GC the function returns true.
493static bool isGCValue(const Value *V, SelectionDAGBuilder &Builder) {
494 auto *Ty = V->getType();
495 if (!Ty->isPtrOrPtrVectorTy())
496 return false;
497 if (auto *GFI = Builder.GFI)
498 if (auto IsManaged = GFI->getStrategy().isGCManagedPointer(Ty))
499 return *IsManaged;
500 return true; // conservative
501}
502
503/// Lower deopt state and gc pointer arguments of the statepoint. The actual
504/// lowering is described in lowerIncomingStatepointValue. This function is
505/// responsible for lowering everything in the right position and playing some
506/// tricks to avoid redundant stack manipulation where possible. On
507/// completion, 'Ops' will contain ready to use operands for machine code
508/// statepoint. The chain nodes will have already been created and the DAG root
509/// will be set to the last value spilled (if any were).
510static void
511lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
512 SmallVectorImpl<MachineMemOperand *> &MemRefs,
513 SmallVectorImpl<SDValue> &GCPtrs,
514 DenseMap<SDValue, int> &LowerAsVReg,
515 SelectionDAGBuilder::StatepointLoweringInfo &SI,
516 SelectionDAGBuilder &Builder) {
517 // Lower the deopt and gc arguments for this statepoint. Layout will be:
518 // deopt argument length, deopt arguments.., gc arguments...
519#ifndef NDEBUG1
520 if (auto *GFI = Builder.GFI) {
521 // Check that each of the gc pointer and bases we've gotten out of the
522 // safepoint is something the strategy thinks might be a pointer (or vector
523 // of pointers) into the GC heap. This is basically just here to help catch
524 // errors during statepoint insertion. TODO: This should actually be in the
525 // Verifier, but we can't get to the GCStrategy from there (yet).
526 GCStrategy &S = GFI->getStrategy();
527 for (const Value *V : SI.Bases) {
528 auto Opt = S.isGCManagedPointer(V->getType()->getScalarType());
529 if (Opt.hasValue()) {
530 assert(Opt.getValue() &&((void)0)
531 "non gc managed base pointer found in statepoint")((void)0);
532 }
533 }
534 for (const Value *V : SI.Ptrs) {
535 auto Opt = S.isGCManagedPointer(V->getType()->getScalarType());
536 if (Opt.hasValue()) {
537 assert(Opt.getValue() &&((void)0)
538 "non gc managed derived pointer found in statepoint")((void)0);
539 }
540 }
541 assert(SI.Bases.size() == SI.Ptrs.size() && "Pointer without base!")((void)0);
542 } else {
543 assert(SI.Bases.empty() && "No gc specified, so cannot relocate pointers!")((void)0);
544 assert(SI.Ptrs.empty() && "No gc specified, so cannot relocate pointers!")((void)0);
545 }
546#endif
547
548 // Figure out what lowering strategy we're going to use for each part
549 // Note: Is is conservatively correct to lower both "live-in" and "live-out"
550 // as "live-through". A "live-through" variable is one which is "live-in",
551 // "live-out", and live throughout the lifetime of the call (i.e. we can find
552 // it from any PC within the transitive callee of the statepoint). In
553 // particular, if the callee spills callee preserved registers we may not
554 // be able to find a value placed in that register during the call. This is
555 // fine for live-out, but not for live-through. If we were willing to make
556 // assumptions about the code generator producing the callee, we could
557 // potentially allow live-through values in callee saved registers.
558 const bool LiveInDeopt =
559 SI.StatepointFlags & (uint64_t)StatepointFlags::DeoptLiveIn;
560
561 // Decide which deriver pointers will go on VRegs
562 unsigned MaxVRegPtrs = MaxRegistersForGCPointers.getValue();
563
564 // Pointers used on exceptional path of invoke statepoint.
565 // We cannot assing them to VRegs.
566 SmallSet<SDValue, 8> LPadPointers;
567 if (!UseRegistersForGCPointersInLandingPad)
7
←
Assuming the condition is false
→
8
←
Taking false branch
→
568 if (auto *StInvoke = dyn_cast_or_null<InvokeInst>(SI.StatepointInstr)) {
569 LandingPadInst *LPI = StInvoke->getLandingPadInst();
570 for (auto *Relocate : SI.GCRelocates)
571 if (Relocate->getOperand(0) == LPI) {
572 LPadPointers.insert(Builder.getValue(Relocate->getBasePtr()));
573 LPadPointers.insert(Builder.getValue(Relocate->getDerivedPtr()));
574 }
575 }
576
577 LLVM_DEBUG(dbgs() << "Deciding how to lower GC Pointers:\n")do { } while (false);
9
←
Loop condition is false. Exiting loop
→
578
579 // List of unique lowered GC Pointer values.
580 SmallSetVector<SDValue, 16> LoweredGCPtrs;
581 // Map lowered GC Pointer value to the index in above vector
582 DenseMap<SDValue, unsigned> GCPtrIndexMap;
583
584 unsigned CurNumVRegs = 0;
585
586 auto canPassGCPtrOnVReg = [&](SDValue SD) {
587 if (SD.getValueType().isVector())
588 return false;
589 if (LPadPointers.count(SD))
590 return false;
591 return !willLowerDirectly(SD);
592 };
593
594 auto processGCPtr = [&](const Value *V) {
595 SDValue PtrSD = Builder.getValue(V);
596 if (!LoweredGCPtrs.insert(PtrSD))
597 return; // skip duplicates
598 GCPtrIndexMap[PtrSD] = LoweredGCPtrs.size() - 1;
599
600 assert(!LowerAsVReg.count(PtrSD) && "must not have been seen")((void)0);
601 if (LowerAsVReg.size() == MaxVRegPtrs)
602 return;
603 assert(V->getType()->isVectorTy() == PtrSD.getValueType().isVector() &&((void)0)
604 "IR and SD types disagree")((void)0);
605 if (!canPassGCPtrOnVReg(PtrSD)) {
606 LLVM_DEBUG(dbgs() << "direct/spill "; PtrSD.dump(&Builder.DAG))do { } while (false);
607 return;
608 }
609 LLVM_DEBUG(dbgs() << "vreg "; PtrSD.dump(&Builder.DAG))do { } while (false);
610 LowerAsVReg[PtrSD] = CurNumVRegs++;
611 };
612
613 // Process derived pointers first to give them more chance to go on VReg.
614 for (const Value *V : SI.Ptrs)
10
←
Assuming '__begin1' is equal to '__end1'
→
615 processGCPtr(V);
616 for (const Value *V : SI.Bases)
11
←
Assuming '__begin1' is equal to '__end1'
→
617 processGCPtr(V);
618
619 LLVM_DEBUG(dbgs() << LowerAsVReg.size() << " pointers will go in vregs\n")do { } while (false);
12
←
Loop condition is false. Exiting loop
→
620
621 auto requireSpillSlot = [&](const Value *V) {
622 if (!Builder.DAG.getTargetLoweringInfo().isTypeLegal(
623 Builder.getValue(V).getValueType()))
624 return true;
625 if (isGCValue(V, Builder))
626 return !LowerAsVReg.count(Builder.getValue(V));
627 return !(LiveInDeopt || UseRegistersForDeoptValues);
628 };
629
630 // Before we actually start lowering (and allocating spill slots for values),
631 // reserve any stack slots which we judge to be profitable to reuse for a
632 // particular value. This is purely an optimization over the code below and
633 // doesn't change semantics at all. It is important for performance that we
634 // reserve slots for both deopt and gc values before lowering either.
635 for (const Value *V : SI.DeoptState) {
13
←
Assuming '__begin1' is equal to '__end1'
→
636 if (requireSpillSlot(V))
637 reservePreviousStackSlotForValue(V, Builder);
638 }
639
640 for (const Value *V : SI.Ptrs) {
14
←
Assuming '__begin1' is equal to '__end1'
→
641 SDValue SDV = Builder.getValue(V);
642 if (!LowerAsVReg.count(SDV))
643 reservePreviousStackSlotForValue(V, Builder);
644 }
645
646 for (const Value *V : SI.Bases) {
15
←
Assuming '__begin1' is equal to '__end1'
→
647 SDValue SDV = Builder.getValue(V);
648 if (!LowerAsVReg.count(SDV))
649 reservePreviousStackSlotForValue(V, Builder);
650 }
651
652 // First, prefix the list with the number of unique values to be
653 // lowered. Note that this is the number of *Values* not the
654 // number of SDValues required to lower them.
655 const int NumVMSArgs = SI.DeoptState.size();
656 pushStackMapConstant(Ops, Builder, NumVMSArgs);
657
658 // The vm state arguments are lowered in an opaque manner. We do not know
659 // what type of values are contained within.
660 LLVM_DEBUG(dbgs() << "Lowering deopt state\n")do { } while (false);
16
←
Loop condition is false. Exiting loop
→
661 for (const Value *V : SI.DeoptState) {
17
←
Assuming '__begin1' is not equal to '__end1'
→
662 SDValue Incoming;
663 // If this is a function argument at a static frame index, generate it as
664 // the frame index.
665 if (const Argument *Arg
18.1
'Arg' is null
18.1
'Arg' is null
18.1
'Arg' is null
 = dyn_cast<Argument>(V)) {
18
←
Assuming 'V' is not a 'Argument'
→
19
←
Taking false branch
→
666 int FI = Builder.FuncInfo.getArgumentFrameIndex(Arg);
667 if (FI != INT_MAX2147483647)
668 Incoming = Builder.DAG.getFrameIndex(FI, Builder.getFrameIndexTy());
669 }
670 if (!Incoming.getNode())
20
←
Taking true branch
→
671 Incoming = Builder.getValue(V);
672 LLVM_DEBUG(dbgs() << "Value " << *Vdo { } while (false)
21
←
Loop condition is false. Exiting loop
→
673 << " requireSpillSlot = " << requireSpillSlot(V) << "\n")do { } while (false);
674 lowerIncomingStatepointValue(Incoming, requireSpillSlot(V), Ops, MemRefs,
22
←
The value of 'Incoming' is assigned to 'Incoming.Node'
→
23
←
Calling 'lowerIncomingStatepointValue'
→
675 Builder);
676 }
677
678 // Finally, go ahead and lower all the gc arguments.
679 pushStackMapConstant(Ops, Builder, LoweredGCPtrs.size());
680 for (SDValue SDV : LoweredGCPtrs)
681 lowerIncomingStatepointValue(SDV, !LowerAsVReg.count(SDV), Ops, MemRefs,
682 Builder);
683
684 // Copy to out vector. LoweredGCPtrs will be empty after this point.
685 GCPtrs = LoweredGCPtrs.takeVector();
686
687 // If there are any explicit spill slots passed to the statepoint, record
688 // them, but otherwise do not do anything special. These are user provided
689 // allocas and give control over placement to the consumer. In this case,
690 // it is the contents of the slot which may get updated, not the pointer to
691 // the alloca
692 SmallVector<SDValue, 4> Allocas;
693 for (Value *V : SI.GCArgs) {
694 SDValue Incoming = Builder.getValue(V);
695 if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Incoming)) {
696 // This handles allocas as arguments to the statepoint
697 assert(Incoming.getValueType() == Builder.getFrameIndexTy() &&((void)0)
698 "Incoming value is a frame index!")((void)0);
699 Allocas.push_back(Builder.DAG.getTargetFrameIndex(
700 FI->getIndex(), Builder.getFrameIndexTy()));
701
702 auto &MF = Builder.DAG.getMachineFunction();
703 auto *MMO = getMachineMemOperand(MF, *FI);
704 MemRefs.push_back(MMO);
705 }
706 }
707 pushStackMapConstant(Ops, Builder, Allocas.size());
708 Ops.append(Allocas.begin(), Allocas.end());
709
710 // Now construct GC base/derived map;
711 pushStackMapConstant(Ops, Builder, SI.Ptrs.size());
712 SDLoc L = Builder.getCurSDLoc();
713 for (unsigned i = 0; i < SI.Ptrs.size(); ++i) {
714 SDValue Base = Builder.getValue(SI.Bases[i]);
715 assert(GCPtrIndexMap.count(Base) && "base not found in index map")((void)0);
716 Ops.push_back(
717 Builder.DAG.getTargetConstant(GCPtrIndexMap[Base], L, MVT::i64));
718 SDValue Derived = Builder.getValue(SI.Ptrs[i]);
719 assert(GCPtrIndexMap.count(Derived) && "derived not found in index map")((void)0);
720 Ops.push_back(
721 Builder.DAG.getTargetConstant(GCPtrIndexMap[Derived], L, MVT::i64));
722 }
723}
724
725SDValue SelectionDAGBuilder::LowerAsSTATEPOINT(
726 SelectionDAGBuilder::StatepointLoweringInfo &SI) {
727 // The basic scheme here is that information about both the original call and
728 // the safepoint is encoded in the CallInst. We create a temporary call and
729 // lower it, then reverse engineer the calling sequence.
730
731 NumOfStatepoints++;
732 // Clear state
733 StatepointLowering.startNewStatepoint(*this);
734 assert(SI.Bases.size() == SI.Ptrs.size())((void)0);
735
736 LLVM_DEBUG(dbgs() << "Lowering statepoint " << *SI.StatepointInstr << "\n")do { } while (false);
5
←
Loop condition is false. Exiting loop
→
737#ifndef NDEBUG1
738 for (auto *Reloc : SI.GCRelocates)
739 if (Reloc->getParent() == SI.StatepointInstr->getParent())
740 StatepointLowering.scheduleRelocCall(*Reloc);
741#endif
742
743 // Lower statepoint vmstate and gcstate arguments
744
745 // All lowered meta args.
746 SmallVector<SDValue, 10> LoweredMetaArgs;
747 // Lowered GC pointers (subset of above).
748 SmallVector<SDValue, 16> LoweredGCArgs;
749 SmallVector<MachineMemOperand*, 16> MemRefs;
750 // Maps derived pointer SDValue to statepoint result of relocated pointer.
751 DenseMap<SDValue, int> LowerAsVReg;
752 lowerStatepointMetaArgs(LoweredMetaArgs, MemRefs, LoweredGCArgs, LowerAsVReg,
6
←
Calling 'lowerStatepointMetaArgs'
→
753 SI, *this);
754
755 // Now that we've emitted the spills, we need to update the root so that the
756 // call sequence is ordered correctly.
757 SI.CLI.setChain(getRoot());
758
759 // Get call node, we will replace it later with statepoint
760 SDValue ReturnVal;
761 SDNode *CallNode;
762 std::tie(ReturnVal, CallNode) =
763 lowerCallFromStatepointLoweringInfo(SI, *this, PendingExports);
764
765 // Construct the actual GC_TRANSITION_START, STATEPOINT, and GC_TRANSITION_END
766 // nodes with all the appropriate arguments and return values.
767
768 // Call Node: Chain, Target, {Args}, RegMask, [Glue]
769 SDValue Chain = CallNode->getOperand(0);
770
771 SDValue Glue;
772 bool CallHasIncomingGlue = CallNode->getGluedNode();
773 if (CallHasIncomingGlue) {
774 // Glue is always last operand
775 Glue = CallNode->getOperand(CallNode->getNumOperands() - 1);
776 }
777
778 // Build the GC_TRANSITION_START node if necessary.
779 //
780 // The operands to the GC_TRANSITION_{START,END} nodes are laid out in the
781 // order in which they appear in the call to the statepoint intrinsic. If
782 // any of the operands is a pointer-typed, that operand is immediately
783 // followed by a SRCVALUE for the pointer that may be used during lowering
784 // (e.g. to form MachinePointerInfo values for loads/stores).
785 const bool IsGCTransition =
786 (SI.StatepointFlags & (uint64_t)StatepointFlags::GCTransition) ==
787 (uint64_t)StatepointFlags::GCTransition;
788 if (IsGCTransition) {
789 SmallVector<SDValue, 8> TSOps;
790
791 // Add chain
792 TSOps.push_back(Chain);
793
794 // Add GC transition arguments
795 for (const Value *V : SI.GCTransitionArgs) {
796 TSOps.push_back(getValue(V));
797 if (V->getType()->isPointerTy())
798 TSOps.push_back(DAG.getSrcValue(V));
799 }
800
801 // Add glue if necessary
802 if (CallHasIncomingGlue)
803 TSOps.push_back(Glue);
804
805 SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
806
807 SDValue GCTransitionStart =
808 DAG.getNode(ISD::GC_TRANSITION_START, getCurSDLoc(), NodeTys, TSOps);
809
810 Chain = GCTransitionStart.getValue(0);
811 Glue = GCTransitionStart.getValue(1);
812 }
813
814 // TODO: Currently, all of these operands are being marked as read/write in
815 // PrologEpilougeInserter.cpp, we should special case the VMState arguments
816 // and flags to be read-only.
817 SmallVector<SDValue, 40> Ops;
818
819 // Add the <id> and <numBytes> constants.
820 Ops.push_back(DAG.getTargetConstant(SI.ID, getCurSDLoc(), MVT::i64));
821 Ops.push_back(
822 DAG.getTargetConstant(SI.NumPatchBytes, getCurSDLoc(), MVT::i32));
823
824 // Calculate and push starting position of vmstate arguments
825 // Get number of arguments incoming directly into call node
826 unsigned NumCallRegArgs =
827 CallNode->getNumOperands() - (CallHasIncomingGlue ? 4 : 3);
828 Ops.push_back(DAG.getTargetConstant(NumCallRegArgs, getCurSDLoc(), MVT::i32));
829
830 // Add call target
831 SDValue CallTarget = SDValue(CallNode->getOperand(1).getNode(), 0);
832 Ops.push_back(CallTarget);
833
834 // Add call arguments
835 // Get position of register mask in the call
836 SDNode::op_iterator RegMaskIt;
837 if (CallHasIncomingGlue)
838 RegMaskIt = CallNode->op_end() - 2;
839 else
840 RegMaskIt = CallNode->op_end() - 1;
841 Ops.insert(Ops.end(), CallNode->op_begin() + 2, RegMaskIt);
842
843 // Add a constant argument for the calling convention
844 pushStackMapConstant(Ops, *this, SI.CLI.CallConv);
845
846 // Add a constant argument for the flags
847 uint64_t Flags = SI.StatepointFlags;
848 assert(((Flags & ~(uint64_t)StatepointFlags::MaskAll) == 0) &&((void)0)
849 "Unknown flag used")((void)0);
850 pushStackMapConstant(Ops, *this, Flags);
851
852 // Insert all vmstate and gcstate arguments
853 llvm::append_range(Ops, LoweredMetaArgs);
854
855 // Add register mask from call node
856 Ops.push_back(*RegMaskIt);
857
858 // Add chain
859 Ops.push_back(Chain);
860
861 // Same for the glue, but we add it only if original call had it
862 if (Glue.getNode())
863 Ops.push_back(Glue);
864
865 // Compute return values. Provide a glue output since we consume one as
866 // input. This allows someone else to chain off us as needed.
867 SmallVector<EVT, 8> NodeTys;
868 for (auto SD : LoweredGCArgs) {
869 if (!LowerAsVReg.count(SD))
870 continue;
871 NodeTys.push_back(SD.getValueType());
872 }
873 LLVM_DEBUG(dbgs() << "Statepoint has " << NodeTys.size() << " results\n")do { } while (false);
874 assert(NodeTys.size() == LowerAsVReg.size() && "Inconsistent GC Ptr lowering")((void)0);
875 NodeTys.push_back(MVT::Other);
876 NodeTys.push_back(MVT::Glue);
877
878 unsigned NumResults = NodeTys.size();
879 MachineSDNode *StatepointMCNode =
880 DAG.getMachineNode(TargetOpcode::STATEPOINT, getCurSDLoc(), NodeTys, Ops);
881 DAG.setNodeMemRefs(StatepointMCNode, MemRefs);
882
883 // For values lowered to tied-defs, create the virtual registers. Note that
884 // for simplicity, we *always* create a vreg even within a single block.
885 DenseMap<SDValue, Register> VirtRegs;
886 for (const auto *Relocate : SI.GCRelocates) {
887 Value *Derived = Relocate->getDerivedPtr();
888 SDValue SD = getValue(Derived);
889 if (!LowerAsVReg.count(SD))
890 continue;
891
892 // Handle multiple gc.relocates of the same input efficiently.
893 if (VirtRegs.count(SD))
894 continue;
895
896 SDValue Relocated = SDValue(StatepointMCNode, LowerAsVReg[SD]);
897
898 auto *RetTy = Relocate->getType();
899 Register Reg = FuncInfo.CreateRegs(RetTy);
900 RegsForValue RFV(*DAG.getContext(), DAG.getTargetLoweringInfo(),
901 DAG.getDataLayout(), Reg, RetTy, None);
902 SDValue Chain = DAG.getRoot();
903 RFV.getCopyToRegs(Relocated, DAG, getCurSDLoc(), Chain, nullptr);
904 PendingExports.push_back(Chain);
905
906 VirtRegs[SD] = Reg;
907 }
908
909 // Record for later use how each relocation was lowered. This is needed to
910 // allow later gc.relocates to mirror the lowering chosen.
911 const Instruction *StatepointInstr = SI.StatepointInstr;
912 auto &RelocationMap = FuncInfo.StatepointRelocationMaps[StatepointInstr];
913 for (const GCRelocateInst *Relocate : SI.GCRelocates) {
914 const Value *V = Relocate->getDerivedPtr();
915 SDValue SDV = getValue(V);
916 SDValue Loc = StatepointLowering.getLocation(SDV);
917
918 RecordType Record;
919 if (LowerAsVReg.count(SDV)) {
920 Record.type = RecordType::VReg;
921 assert(VirtRegs.count(SDV))((void)0);
922 Record.payload.Reg = VirtRegs[SDV];
923 } else if (Loc.getNode()) {
924 Record.type = RecordType::Spill;
925 Record.payload.FI = cast<FrameIndexSDNode>(Loc)->getIndex();
926 } else {
927 Record.type = RecordType::NoRelocate;
928 // If we didn't relocate a value, we'll essentialy end up inserting an
929 // additional use of the original value when lowering the gc.relocate.
930 // We need to make sure the value is available at the new use, which
931 // might be in another block.
932 if (Relocate->getParent() != StatepointInstr->getParent())
933 ExportFromCurrentBlock(V);
934 }
935 RelocationMap[V] = Record;
936 }
937
938
939
940 SDNode *SinkNode = StatepointMCNode;
941
942 // Build the GC_TRANSITION_END node if necessary.
943 //
944 // See the comment above regarding GC_TRANSITION_START for the layout of
945 // the operands to the GC_TRANSITION_END node.
946 if (IsGCTransition) {
947 SmallVector<SDValue, 8> TEOps;
948
949 // Add chain
950 TEOps.push_back(SDValue(StatepointMCNode, NumResults - 2));
951
952 // Add GC transition arguments
953 for (const Value *V : SI.GCTransitionArgs) {
954 TEOps.push_back(getValue(V));
955 if (V->getType()->isPointerTy())
956 TEOps.push_back(DAG.getSrcValue(V));
957 }
958
959 // Add glue
960 TEOps.push_back(SDValue(StatepointMCNode, NumResults - 1));
961
962 SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
963
964 SDValue GCTransitionStart =
965 DAG.getNode(ISD::GC_TRANSITION_END, getCurSDLoc(), NodeTys, TEOps);
966
967 SinkNode = GCTransitionStart.getNode();
968 }
969
970 // Replace original call
971 // Call: ch,glue = CALL ...
972 // Statepoint: [gc relocates],ch,glue = STATEPOINT ...
973 unsigned NumSinkValues = SinkNode->getNumValues();
974 SDValue StatepointValues[2] = {SDValue(SinkNode, NumSinkValues - 2),
975 SDValue(SinkNode, NumSinkValues - 1)};
976 DAG.ReplaceAllUsesWith(CallNode, StatepointValues);
977 // Remove original call node
978 DAG.DeleteNode(CallNode);
979
980 // Since we always emit CopyToRegs (even for local relocates), we must
981 // update root, so that they are emitted before any local uses.
982 (void)getControlRoot();
983
984 // TODO: A better future implementation would be to emit a single variable
985 // argument, variable return value STATEPOINT node here and then hookup the
986 // return value of each gc.relocate to the respective output of the
987 // previously emitted STATEPOINT value. Unfortunately, this doesn't appear
988 // to actually be possible today.
989
990 return ReturnVal;
991}
992
993void
994SelectionDAGBuilder::LowerStatepoint(const GCStatepointInst &I,
995 const BasicBlock *EHPadBB /*= nullptr*/) {
996 assert(I.getCallingConv() != CallingConv::AnyReg &&((void)0)
997 "anyregcc is not supported on statepoints!")((void)0);
998
999#ifndef NDEBUG1
1000 // Check that the associated GCStrategy expects to encounter statepoints.
1001 assert(GFI->getStrategy().useStatepoints() &&((void)0)
1002 "GCStrategy does not expect to encounter statepoints")((void)0);
1003#endif
1004
1005 SDValue ActualCallee;
1006 SDValue Callee = getValue(I.getActualCalledOperand());
1007
1008 if (I.getNumPatchBytes() > 0) {
1009 // If we've been asked to emit a nop sequence instead of a call instruction
1010 // for this statepoint then don't lower the call target, but use a constant
1011 // `undef` instead. Not lowering the call target lets statepoint clients
1012 // get away without providing a physical address for the symbolic call
1013 // target at link time.
1014 ActualCallee = DAG.getUNDEF(Callee.getValueType());
1015 } else {
1016 ActualCallee = Callee;
1017 }
1018
1019 StatepointLoweringInfo SI(DAG);
1020 populateCallLoweringInfo(SI.CLI, &I, GCStatepointInst::CallArgsBeginPos,
1021 I.getNumCallArgs(), ActualCallee,
1022 I.getActualReturnType(), false /* IsPatchPoint */);
1023
1024 // There may be duplication in the gc.relocate list; such as two copies of
1025 // each relocation on normal and exceptional path for an invoke. We only
1026 // need to spill once and record one copy in the stackmap, but we need to
1027 // reload once per gc.relocate. (Dedupping gc.relocates is trickier and best
1028 // handled as a CSE problem elsewhere.)
1029 // TODO: There a couple of major stackmap size optimizations we could do
1030 // here if we wished.
1031 // 1) If we've encountered a derived pair {B, D}, we don't need to actually
1032 // record {B,B} if it's seen later.
1033 // 2) Due to rematerialization, actual derived pointers are somewhat rare;
1034 // given that, we could change the format to record base pointer relocations
1035 // separately with half the space. This would require a format rev and a
1036 // fairly major rework of the STATEPOINT node though.
1037 SmallSet<SDValue, 8> Seen;
1038 for (const GCRelocateInst *Relocate : I.getGCRelocates()) {
1039 SI.GCRelocates.push_back(Relocate);
1040
1041 SDValue DerivedSD = getValue(Relocate->getDerivedPtr());
1042 if (Seen.insert(DerivedSD).second) {
1043 SI.Bases.push_back(Relocate->getBasePtr());
1044 SI.Ptrs.push_back(Relocate->getDerivedPtr());
1045 }
1046 }
1047
1048 // If we find a deopt value which isn't explicitly added, we need to
1049 // ensure it gets lowered such that gc cycles occurring before the
1050 // deoptimization event during the lifetime of the call don't invalidate
1051 // the pointer we're deopting with. Note that we assume that all
1052 // pointers passed to deopt are base pointers; relaxing that assumption
1053 // would require relatively large changes to how we represent relocations.
1054 for (Value *V : I.deopt_operands()) {
1055 if (!isGCValue(V, *this))
1056 continue;
1057 if (Seen.insert(getValue(V)).second) {
1058 SI.Bases.push_back(V);
1059 SI.Ptrs.push_back(V);
1060 }
1061 }
1062
1063 SI.GCArgs = ArrayRef<const Use>(I.gc_args_begin(), I.gc_args_end());
1064 SI.StatepointInstr = &I;
1065 SI.ID = I.getID();
1066
1067 SI.DeoptState = ArrayRef<const Use>(I.deopt_begin(), I.deopt_end());
1068 SI.GCTransitionArgs = ArrayRef<const Use>(I.gc_transition_args_begin(),
1069 I.gc_transition_args_end());
1070
1071 SI.StatepointFlags = I.getFlags();
1072 SI.NumPatchBytes = I.getNumPatchBytes();
1073 SI.EHPadBB = EHPadBB;
1074
1075 SDValue ReturnValue = LowerAsSTATEPOINT(SI);
1076
1077 // Export the result value if needed
1078 const std::pair<bool, bool> GCResultLocality = I.getGCResultLocality();
1079 Type *RetTy = I.getActualReturnType();
1080
1081 if (RetTy->isVoidTy() ||
1082 (!GCResultLocality.first && !GCResultLocality.second)) {
1083 // The return value is not needed, just generate a poison value.
1084 setValue(&I, DAG.getIntPtrConstant(-1, getCurSDLoc()));
1085 return;
1086 }
1087
1088 if (GCResultLocality.first) {
1089 // Result value will be used in a same basic block. Don't export it or
1090 // perform any explicit register copies. The gc_result will simply grab
1091 // this value.
1092 setValue(&I, ReturnValue);
1093 }
1094
1095 if (!GCResultLocality.second)
1096 return;
1097 // Result value will be used in a different basic block so we need to export
1098 // it now. Default exporting mechanism will not work here because statepoint
1099 // call has a different type than the actual call. It means that by default
1100 // llvm will create export register of the wrong type (always i32 in our
1101 // case). So instead we need to create export register with correct type
1102 // manually.
1103 // TODO: To eliminate this problem we can remove gc.result intrinsics
1104 // completely and make statepoint call to return a tuple.
1105 unsigned Reg = FuncInfo.CreateRegs(RetTy);
1106 RegsForValue RFV(*DAG.getContext(), DAG.getTargetLoweringInfo(),
1107 DAG.getDataLayout(), Reg, RetTy,
1108 I.getCallingConv());
1109 SDValue Chain = DAG.getEntryNode();
1110
1111 RFV.getCopyToRegs(ReturnValue, DAG, getCurSDLoc(), Chain, nullptr);
1112 PendingExports.push_back(Chain);
1113 FuncInfo.ValueMap[&I] = Reg;
1114}
1115
1116void SelectionDAGBuilder::LowerCallSiteWithDeoptBundleImpl(
1117 const CallBase *Call, SDValue Callee, const BasicBlock *EHPadBB,
1118 bool VarArgDisallowed, bool ForceVoidReturnTy) {
1119 StatepointLoweringInfo SI(DAG);
1120 unsigned ArgBeginIndex = Call->arg_begin() - Call->op_begin();
1121 populateCallLoweringInfo(
1122 SI.CLI, Call, ArgBeginIndex, Call->getNumArgOperands(), Callee,
1123 ForceVoidReturnTy
1.1
'ForceVoidReturnTy' is true
1.1
'ForceVoidReturnTy' is true
1.1
'ForceVoidReturnTy' is true
 ? Type::getVoidTy(*DAG.getContext()) : Call->getType(),
2
←
'?' condition is true
→
1124 false);
1125 if (!VarArgDisallowed
2.1
'VarArgDisallowed' is true
2.1
'VarArgDisallowed' is true
2.1
'VarArgDisallowed' is true
)
3
←
Taking false branch
→
1126 SI.CLI.IsVarArg = Call->getFunctionType()->isVarArg();
1127
1128 auto DeoptBundle = *Call->getOperandBundle(LLVMContext::OB_deopt);
1129
1130 unsigned DefaultID = StatepointDirectives::DeoptBundleStatepointID;
1131
1132 auto SD = parseStatepointDirectivesFromAttrs(Call->getAttributes());
1133 SI.ID = SD.StatepointID.getValueOr(DefaultID);
1134 SI.NumPatchBytes = SD.NumPatchBytes.getValueOr(0);
1135
1136 SI.DeoptState =
1137 ArrayRef<const Use>(DeoptBundle.Inputs.begin(), DeoptBundle.Inputs.end());
1138 SI.StatepointFlags = static_cast<uint64_t>(StatepointFlags::None);
1139 SI.EHPadBB = EHPadBB;
1140
1141 // NB! The GC arguments are deliberately left empty.
1142
1143 if (SDValue ReturnVal = LowerAsSTATEPOINT(SI)) {
4
←
Calling 'SelectionDAGBuilder::LowerAsSTATEPOINT'
→
1144 ReturnVal = lowerRangeToAssertZExt(DAG, *Call, ReturnVal);
1145 setValue(Call, ReturnVal);
1146 }
1147}
1148
1149void SelectionDAGBuilder::LowerCallSiteWithDeoptBundle(
1150 const CallBase *Call, SDValue Callee, const BasicBlock *EHPadBB) {
1151 LowerCallSiteWithDeoptBundleImpl(Call, Callee, EHPadBB,
1152 /* VarArgDisallowed = */ false,
1153 /* ForceVoidReturnTy = */ false);
1154}
1155
1156void SelectionDAGBuilder::visitGCResult(const GCResultInst &CI) {
1157 // The result value of the gc_result is simply the result of the actual
1158 // call. We've already emitted this, so just grab the value.
1159 const GCStatepointInst *SI = CI.getStatepoint();
1160
1161 if (SI->getParent() == CI.getParent()) {
1162 setValue(&CI, getValue(SI));
1163 return;
1164 }
1165 // Statepoint is in different basic block so we should have stored call
1166 // result in a virtual register.
1167 // We can not use default getValue() functionality to copy value from this
1168 // register because statepoint and actual call return types can be
1169 // different, and getValue() will use CopyFromReg of the wrong type,
1170 // which is always i32 in our case.
1171 Type *RetTy = SI->getActualReturnType();
1172 SDValue CopyFromReg = getCopyFromRegs(SI, RetTy);
1173
1174 assert(CopyFromReg.getNode())((void)0);
1175 setValue(&CI, CopyFromReg);
1176}
1177
1178void SelectionDAGBuilder::visitGCRelocate(const GCRelocateInst &Relocate) {
1179#ifndef NDEBUG1
1180 // Consistency check
1181 // We skip this check for relocates not in the same basic block as their
1182 // statepoint. It would be too expensive to preserve validation info through
1183 // different basic blocks.
1184 if (Relocate.getStatepoint()->getParent() == Relocate.getParent())
1185 StatepointLowering.relocCallVisited(Relocate);
1186
1187 auto *Ty = Relocate.getType()->getScalarType();
1188 if (auto IsManaged = GFI->getStrategy().isGCManagedPointer(Ty))
1189 assert(*IsManaged && "Non gc managed pointer relocated!")((void)0);
1190#endif
1191
1192 const Value *DerivedPtr = Relocate.getDerivedPtr();
1193 auto &RelocationMap =
1194 FuncInfo.StatepointRelocationMaps[Relocate.getStatepoint()];
1195 auto SlotIt = RelocationMap.find(DerivedPtr);
1196 assert(SlotIt != RelocationMap.end() && "Relocating not lowered gc value")((void)0);
1197 const RecordType &Record = SlotIt->second;
1198
1199 // If relocation was done via virtual register..
1200 if (Record.type == RecordType::VReg) {
1201 Register InReg = Record.payload.Reg;
1202 RegsForValue RFV(*DAG.getContext(), DAG.getTargetLoweringInfo(),
1203 DAG.getDataLayout(), InReg, Relocate.getType(),
1204 None); // This is not an ABI copy.
1205 // We generate copy to/from regs even for local uses, hence we must
1206 // chain with current root to ensure proper ordering of copies w.r.t.
1207 // statepoint.
1208 SDValue Chain = DAG.getRoot();
1209 SDValue Relocation = RFV.getCopyFromRegs(DAG, FuncInfo, getCurSDLoc(),
1210 Chain, nullptr, nullptr);
1211 setValue(&Relocate, Relocation);
1212 return;
1213 }
1214
1215 if (Record.type == RecordType::Spill) {
1216 unsigned Index = Record.payload.FI;
1217 SDValue SpillSlot = DAG.getTargetFrameIndex(Index, getFrameIndexTy());
1218
1219 // All the reloads are independent and are reading memory only modified by
1220 // statepoints (i.e. no other aliasing stores); informing SelectionDAG of
1221 // this this let's CSE kick in for free and allows reordering of
1222 // instructions if possible. The lowering for statepoint sets the root,
1223 // so this is ordering all reloads with the either
1224 // a) the statepoint node itself, or
1225 // b) the entry of the current block for an invoke statepoint.
1226 const SDValue Chain = DAG.getRoot(); // != Builder.getRoot()
1227
1228 auto &MF = DAG.getMachineFunction();
1229 auto &MFI = MF.getFrameInfo();
1230 auto PtrInfo = MachinePointerInfo::getFixedStack(MF, Index);
1231 auto *LoadMMO = MF.getMachineMemOperand(PtrInfo, MachineMemOperand::MOLoad,
1232 MFI.getObjectSize(Index),
1233 MFI.getObjectAlign(Index));
1234
1235 auto LoadVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(),
1236 Relocate.getType());
1237
1238 SDValue SpillLoad =
1239 DAG.getLoad(LoadVT, getCurSDLoc(), Chain, SpillSlot, LoadMMO);
1240 PendingLoads.push_back(SpillLoad.getValue(1));
1241
1242 assert(SpillLoad.getNode())((void)0);
1243 setValue(&Relocate, SpillLoad);
1244 return;
1245 }
1246
1247 assert(Record.type == RecordType::NoRelocate)((void)0);
1248 SDValue SD = getValue(DerivedPtr);
1249
1250 if (SD.isUndef() && SD.getValueType().getSizeInBits() <= 64) {
1251 // Lowering relocate(undef) as arbitrary constant. Current constant value
1252 // is chosen such that it's unlikely to be a valid pointer.
1253 setValue(&Relocate, DAG.getTargetConstant(0xFEFEFEFE, SDLoc(SD), MVT::i64));
1254 return;
1255 }
1256
1257 // We didn't need to spill these special cases (constants and allocas).
1258 // See the handling in spillIncomingValueForStatepoint for detail.
1259 setValue(&Relocate, SD);
1260}
1261
1262void SelectionDAGBuilder::LowerDeoptimizeCall(const CallInst *CI) {
1263 const auto &TLI = DAG.getTargetLoweringInfo();
1264 SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(RTLIB::DEOPTIMIZE),
1265 TLI.getPointerTy(DAG.getDataLayout()));
1266
1267 // We don't lower calls to __llvm_deoptimize as varargs, but as a regular
1268 // call. We also do not lower the return value to any virtual register, and
1269 // change the immediately following return to a trap instruction.
1270 LowerCallSiteWithDeoptBundleImpl(CI, Callee, /* EHPadBB = */ nullptr,
1
Calling 'SelectionDAGBuilder::LowerCallSiteWithDeoptBundleImpl'
→
1271 /* VarArgDisallowed = */ true,
1272 /* ForceVoidReturnTy = */ true);
1273}
1274
1275void SelectionDAGBuilder::LowerDeoptimizingReturn() {
1276 // We do not lower the return value from llvm.deoptimize to any virtual
1277 // register, and change the immediately following return to a trap
1278 // instruction.
1279 if (DAG.getTarget().Options.TrapUnreachable)
1280 DAG.setRoot(
1281 DAG.getNode(ISD::TRAP, getCurSDLoc(), MVT::Other, DAG.getRoot()));
1282}
←

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Support/Casting.h

→
1//===- llvm/Support/Casting.h - Allow flexible, checked, casts --*- 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 defines the isa<X>(), cast<X>(), dyn_cast<X>(), cast_or_null<X>(),
10// and dyn_cast_or_null<X>() templates.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_CASTING_H
15#define LLVM_SUPPORT_CASTING_H
16
17#include "llvm/Support/Compiler.h"
18#include "llvm/Support/type_traits.h"
19#include <cassert>
20#include <memory>
21#include <type_traits>
22
23namespace llvm {
24
25//===----------------------------------------------------------------------===//
26// isa<x> Support Templates
27//===----------------------------------------------------------------------===//
28
29// Define a template that can be specialized by smart pointers to reflect the
30// fact that they are automatically dereferenced, and are not involved with the
31// template selection process... the default implementation is a noop.
32//
33template<typename From> struct simplify_type {
34 using SimpleType = From; // The real type this represents...
35
36 // An accessor to get the real value...
37 static SimpleType &getSimplifiedValue(From &Val) { return Val; }
38};
39
40template<typename From> struct simplify_type<const From> {
41 using NonConstSimpleType = typename simplify_type<From>::SimpleType;
42 using SimpleType =
43 typename add_const_past_pointer<NonConstSimpleType>::type;
44 using RetType =
45 typename add_lvalue_reference_if_not_pointer<SimpleType>::type;
46
47 static RetType getSimplifiedValue(const From& Val) {
48 return simplify_type<From>::getSimplifiedValue(const_cast<From&>(Val));
49 }
50};
51
52// The core of the implementation of isa<X> is here; To and From should be
53// the names of classes. This template can be specialized to customize the
54// implementation of isa<> without rewriting it from scratch.
55template <typename To, typename From, typename Enabler = void>
56struct isa_impl {
57 static inline bool doit(const From &Val) {
58 return To::classof(&Val);
59 }
60};
61
62/// Always allow upcasts, and perform no dynamic check for them.
63template <typename To, typename From>
64struct isa_impl<To, From, std::enable_if_t<std::is_base_of<To, From>::value>> {
65 static inline bool doit(const From &) { return true; }
66};
67
68template <typename To, typename From> struct isa_impl_cl {
69 static inline bool doit(const From &Val) {
70 return isa_impl<To, From>::doit(Val);
71 }
72};
73
74template <typename To, typename From> struct isa_impl_cl<To, const From> {
75 static inline bool doit(const From &Val) {
76 return isa_impl<To, From>::doit(Val);
77 }
78};
79
80template <typename To, typename From>
81struct isa_impl_cl<To, const std::unique_ptr<From>> {
82 static inline bool doit(const std::unique_ptr<From> &Val) {
83 assert(Val && "isa<> used on a null pointer")((void)0);
84 return isa_impl_cl<To, From>::doit(*Val);
85 }
86};
87
88template <typename To, typename From> struct isa_impl_cl<To, From*> {
89 static inline bool doit(const From *Val) {
90 assert(Val && "isa<> used on a null pointer")((void)0);
91 return isa_impl<To, From>::doit(*Val);
92 }
93};
94
95template <typename To, typename From> struct isa_impl_cl<To, From*const> {
96 static inline bool doit(const From *Val) {
97 assert(Val && "isa<> used on a null pointer")((void)0);
98 return isa_impl<To, From>::doit(*Val);
99 }
100};
101
102template <typename To, typename From> struct isa_impl_cl<To, const From*> {
103 static inline bool doit(const From *Val) {
104 assert(Val && "isa<> used on a null pointer")((void)0);
105 return isa_impl<To, From>::doit(*Val);
106 }
107};
108
109template <typename To, typename From> struct isa_impl_cl<To, const From*const> {
110 static inline bool doit(const From *Val) {
111 assert(Val && "isa<> used on a null pointer")((void)0);
112 return isa_impl<To, From>::doit(*Val);
113 }
114};
115
116template<typename To, typename From, typename SimpleFrom>
117struct isa_impl_wrap {
118 // When From != SimplifiedType, we can simplify the type some more by using
119 // the simplify_type template.
120 static bool doit(const From &Val) {
121 return isa_impl_wrap<To, SimpleFrom,
122 typename simplify_type<SimpleFrom>::SimpleType>::doit(
123 simplify_type<const From>::getSimplifiedValue(Val));
124 }
125};
126
127template<typename To, typename FromTy>
128struct isa_impl_wrap<To, FromTy, FromTy> {
129 // When From == SimpleType, we are as simple as we are going to get.
130 static bool doit(const FromTy &Val) {
131 return isa_impl_cl<To,FromTy>::doit(Val);
132 }
133};
134
135// isa<X> - Return true if the parameter to the template is an instance of one
136// of the template type arguments. Used like this:
137//
138// if (isa<Type>(myVal)) { ... }
139// if (isa<Type0, Type1, Type2>(myVal)) { ... }
140//
141template <class X, class Y> LLVM_NODISCARD[[clang::warn_unused_result]] inline bool isa(const Y &Val) {
142 return isa_impl_wrap<X, const Y,
143 typename simplify_type<const Y>::SimpleType>::doit(Val);
144}
145
146template <typename First, typename Second, typename... Rest, typename Y>
147LLVM_NODISCARD[[clang::warn_unused_result]] inline bool isa(const Y &Val) {
148 return isa<First>(Val) || isa<Second, Rest...>(Val);
149}
150
151// isa_and_nonnull<X> - Functionally identical to isa, except that a null value
152// is accepted.
153//
154template <typename... X, class Y>
155LLVM_NODISCARD[[clang::warn_unused_result]] inline bool isa_and_nonnull(const Y &Val) {
156 if (!Val)
157 return false;
158 return isa<X...>(Val);
159}
160
161//===----------------------------------------------------------------------===//
162// cast<x> Support Templates
163//===----------------------------------------------------------------------===//
164
165template<class To, class From> struct cast_retty;
166
167// Calculate what type the 'cast' function should return, based on a requested
168// type of To and a source type of From.
169template<class To, class From> struct cast_retty_impl {
170 using ret_type = To &; // Normal case, return Ty&
171};
172template<class To, class From> struct cast_retty_impl<To, const From> {
173 using ret_type = const To &; // Normal case, return Ty&
174};
175
176template<class To, class From> struct cast_retty_impl<To, From*> {
177 using ret_type = To *; // Pointer arg case, return Ty*
178};
179
180template<class To, class From> struct cast_retty_impl<To, const From*> {
181 using ret_type = const To *; // Constant pointer arg case, return const Ty*
182};
183
184template<class To, class From> struct cast_retty_impl<To, const From*const> {
185 using ret_type = const To *; // Constant pointer arg case, return const Ty*
186};
187
188template <class To, class From>
189struct cast_retty_impl<To, std::unique_ptr<From>> {
190private:
191 using PointerType = typename cast_retty_impl<To, From *>::ret_type;
192 using ResultType = std::remove_pointer_t<PointerType>;
193
194public:
195 using ret_type = std::unique_ptr<ResultType>;
196};
197
198template<class To, class From, class SimpleFrom>
199struct cast_retty_wrap {
200 // When the simplified type and the from type are not the same, use the type
201 // simplifier to reduce the type, then reuse cast_retty_impl to get the
202 // resultant type.
203 using ret_type = typename cast_retty<To, SimpleFrom>::ret_type;
204};
205
206template<class To, class FromTy>
207struct cast_retty_wrap<To, FromTy, FromTy> {
208 // When the simplified type is equal to the from type, use it directly.
209 using ret_type = typename cast_retty_impl<To,FromTy>::ret_type;
210};
211
212template<class To, class From>
213struct cast_retty {
214 using ret_type = typename cast_retty_wrap<
215 To, From, typename simplify_type<From>::SimpleType>::ret_type;
216};
217
218// Ensure the non-simple values are converted using the simplify_type template
219// that may be specialized by smart pointers...
220//
221template<class To, class From, class SimpleFrom> struct cast_convert_val {
222 // This is not a simple type, use the template to simplify it...
223 static typename cast_retty<To, From>::ret_type doit(From &Val) {
224 return cast_convert_val<To, SimpleFrom,
33
←
Returning without writing to 'Val.Node'
→
225 typename simplify_type<SimpleFrom>::SimpleType>::doit(
226 simplify_type<From>::getSimplifiedValue(Val));
30
←
Calling 'simplify_type::getSimplifiedValue'
→
32
←
Returning from 'simplify_type::getSimplifiedValue'
→
227 }
228};
229
230template<class To, class FromTy> struct cast_convert_val<To,FromTy,FromTy> {
231 // This _is_ a simple type, just cast it.
232 static typename cast_retty<To, FromTy>::ret_type doit(const FromTy &Val) {
233 typename cast_retty<To, FromTy>::ret_type Res2
234 = (typename cast_retty<To, FromTy>::ret_type)const_cast<FromTy&>(Val);
235 return Res2;
236 }
237};
238
239template <class X> struct is_simple_type {
240 static const bool value =
241 std::is_same<X, typename simplify_type<X>::SimpleType>::value;
242};
243
244// cast<X> - Return the argument parameter cast to the specified type. This
245// casting operator asserts that the type is correct, so it does not return null
246// on failure. It does not allow a null argument (use cast_or_null for that).
247// It is typically used like this:
248//
249// cast<Instruction>(myVal)->getParent()
250//
251template <class X, class Y>
252inline std::enable_if_t<!is_simple_type<Y>::value,
253 typename cast_retty<X, const Y>::ret_type>
254cast(const Y &Val) {
255 assert(isa<X>(Val) && "cast<Ty>() argument of incompatible type!")((void)0);
256 return cast_convert_val<
257 X, const Y, typename simplify_type<const Y>::SimpleType>::doit(Val);
258}
259
260template <class X, class Y>
261inline typename cast_retty<X, Y>::ret_type cast(Y &Val) {
262 assert(isa<X>(Val) && "cast<Ty>() argument of incompatible type!")((void)0);
263 return cast_convert_val<X, Y,
29
←
Calling 'cast_convert_val::doit'
→
34
←
Returning from 'cast_convert_val::doit'
→
35
←
Returning without writing to 'Val.Node'
→
264 typename simplify_type<Y>::SimpleType>::doit(Val);
265}
266
267template <class X, class Y>
268inline typename cast_retty<X, Y *>::ret_type cast(Y *Val) {
269 assert(isa<X>(Val) && "cast<Ty>() argument of incompatible type!")((void)0);
270 return cast_convert_val<X, Y*,
271 typename simplify_type<Y*>::SimpleType>::doit(Val);
272}
273
274template <class X, class Y>
275inline typename cast_retty<X, std::unique_ptr<Y>>::ret_type
276cast(std::unique_ptr<Y> &&Val) {
277 assert(isa<X>(Val.get()) && "cast<Ty>() argument of incompatible type!")((void)0);
278 using ret_type = typename cast_retty<X, std::unique_ptr<Y>>::ret_type;
279 return ret_type(
280 cast_convert_val<X, Y *, typename simplify_type<Y *>::SimpleType>::doit(
281 Val.release()));
282}
283
284// cast_or_null<X> - Functionally identical to cast, except that a null value is
285// accepted.
286//
287template <class X, class Y>
288LLVM_NODISCARD[[clang::warn_unused_result]] inline std::enable_if_t<
289 !is_simple_type<Y>::value, typename cast_retty<X, const Y>::ret_type>
290cast_or_null(const Y &Val) {
291 if (!Val)
292 return nullptr;
293 assert(isa<X>(Val) && "cast_or_null<Ty>() argument of incompatible type!")((void)0);
294 return cast<X>(Val);
295}
296
297template <class X, class Y>
298LLVM_NODISCARD[[clang::warn_unused_result]] inline std::enable_if_t<!is_simple_type<Y>::value,
299 typename cast_retty<X, Y>::ret_type>
300cast_or_null(Y &Val) {
301 if (!Val)
302 return nullptr;
303 assert(isa<X>(Val) && "cast_or_null<Ty>() argument of incompatible type!")((void)0);
304 return cast<X>(Val);
305}
306
307template <class X, class Y>
308LLVM_NODISCARD[[clang::warn_unused_result]] inline typename cast_retty<X, Y *>::ret_type
309cast_or_null(Y *Val) {
310 if (!Val) return nullptr;
311 assert(isa<X>(Val) && "cast_or_null<Ty>() argument of incompatible type!")((void)0);
312 return cast<X>(Val);
313}
314
315template <class X, class Y>
316inline typename cast_retty<X, std::unique_ptr<Y>>::ret_type
317cast_or_null(std::unique_ptr<Y> &&Val) {
318 if (!Val)
319 return nullptr;
320 return cast<X>(std::move(Val));
321}
322
323// dyn_cast<X> - Return the argument parameter cast to the specified type. This
324// casting operator returns null if the argument is of the wrong type, so it can
325// be used to test for a type as well as cast if successful. This should be
326// used in the context of an if statement like this:
327//
328// if (const Instruction *I = dyn_cast<Instruction>(myVal)) { ... }
329//
330
331template <class X, class Y>
332LLVM_NODISCARD[[clang::warn_unused_result]] inline std::enable_if_t<
333 !is_simple_type<Y>::value, typename cast_retty<X, const Y>::ret_type>
334dyn_cast(const Y &Val) {
335 return isa<X>(Val) ? cast<X>(Val) : nullptr;
336}
337
338template <class X, class Y>
339LLVM_NODISCARD[[clang::warn_unused_result]] inline typename cast_retty<X, Y>::ret_type dyn_cast(Y &Val) {
340 return isa<X>(Val) ? cast<X>(Val) : nullptr;
26
←
Assuming 'Val' is a 'FrameIndexSDNode'
→
27
←
'?' condition is true
→
28
←
Calling 'cast<llvm::FrameIndexSDNode, llvm::SDValue>'
→
36
←
Returning from 'cast<llvm::FrameIndexSDNode, llvm::SDValue>'
→
37
←
Returning without writing to 'Val.Node'
→
341}
342
343template <class X, class Y>
344LLVM_NODISCARD[[clang::warn_unused_result]] inline typename cast_retty<X, Y *>::ret_type dyn_cast(Y *Val) {
345 return isa<X>(Val) ? cast<X>(Val) : nullptr;
346}
347
348// dyn_cast_or_null<X> - Functionally identical to dyn_cast, except that a null
349// value is accepted.
350//
351template <class X, class Y>
352LLVM_NODISCARD[[clang::warn_unused_result]] inline std::enable_if_t<
353 !is_simple_type<Y>::value, typename cast_retty<X, const Y>::ret_type>
354dyn_cast_or_null(const Y &Val) {
355 return (Val && isa<X>(Val)) ? cast<X>(Val) : nullptr;
356}
357
358template <class X, class Y>
359LLVM_NODISCARD[[clang::warn_unused_result]] inline std::enable_if_t<!is_simple_type<Y>::value,
360 typename cast_retty<X, Y>::ret_type>
361dyn_cast_or_null(Y &Val) {
362 return (Val && isa<X>(Val)) ? cast<X>(Val) : nullptr;
363}
364
365template <class X, class Y>
366LLVM_NODISCARD[[clang::warn_unused_result]] inline typename cast_retty<X, Y *>::ret_type
367dyn_cast_or_null(Y *Val) {
368 return (Val && isa<X>(Val)) ? cast<X>(Val) : nullptr;
369}
370
371// unique_dyn_cast<X> - Given a unique_ptr<Y>, try to return a unique_ptr<X>,
372// taking ownership of the input pointer iff isa<X>(Val) is true. If the
373// cast is successful, From refers to nullptr on exit and the casted value
374// is returned. If the cast is unsuccessful, the function returns nullptr
375// and From is unchanged.
376template <class X, class Y>
377LLVM_NODISCARD[[clang::warn_unused_result]] inline auto unique_dyn_cast(std::unique_ptr<Y> &Val)
378 -> decltype(cast<X>(Val)) {
379 if (!isa<X>(Val))
380 return nullptr;
381 return cast<X>(std::move(Val));
382}
383
384template <class X, class Y>
385LLVM_NODISCARD[[clang::warn_unused_result]] inline auto unique_dyn_cast(std::unique_ptr<Y> &&Val) {
386 return unique_dyn_cast<X, Y>(Val);
387}
388
389// dyn_cast_or_null<X> - Functionally identical to unique_dyn_cast, except that
390// a null value is accepted.
391template <class X, class Y>
392LLVM_NODISCARD[[clang::warn_unused_result]] inline auto unique_dyn_cast_or_null(std::unique_ptr<Y> &Val)
393 -> decltype(cast<X>(Val)) {
394 if (!Val)
395 return nullptr;
396 return unique_dyn_cast<X, Y>(Val);
397}
398
399template <class X, class Y>
400LLVM_NODISCARD[[clang::warn_unused_result]] inline auto unique_dyn_cast_or_null(std::unique_ptr<Y> &&Val) {
401 return unique_dyn_cast_or_null<X, Y>(Val);
402}
403
404} // end namespace llvm
405
406#endif // LLVM_SUPPORT_CASTING_H
←

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/CodeGen/SelectionDAGNodes.h

1//===- llvm/CodeGen/SelectionDAGNodes.h - SelectionDAG Nodes ----*- 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 declares the SDNode class and derived classes, which are used to
10// represent the nodes and operations present in a SelectionDAG. These nodes
11// and operations are machine code level operations, with some similarities to
12// the GCC RTL representation.
13//
14// Clients should include the SelectionDAG.h file instead of this file directly.
15//
16//===----------------------------------------------------------------------===//
17
18#ifndef LLVM_CODEGEN_SELECTIONDAGNODES_H
19#define LLVM_CODEGEN_SELECTIONDAGNODES_H
20
21#include "llvm/ADT/APFloat.h"
22#include "llvm/ADT/ArrayRef.h"
23#include "llvm/ADT/BitVector.h"
24#include "llvm/ADT/FoldingSet.h"
25#include "llvm/ADT/GraphTraits.h"
26#include "llvm/ADT/SmallPtrSet.h"
27#include "llvm/ADT/SmallVector.h"
28#include "llvm/ADT/ilist_node.h"
29#include "llvm/ADT/iterator.h"
30#include "llvm/ADT/iterator_range.h"
31#include "llvm/CodeGen/ISDOpcodes.h"
32#include "llvm/CodeGen/MachineMemOperand.h"
33#include "llvm/CodeGen/Register.h"
34#include "llvm/CodeGen/ValueTypes.h"
35#include "llvm/IR/Constants.h"
36#include "llvm/IR/DebugLoc.h"
37#include "llvm/IR/Instruction.h"
38#include "llvm/IR/Instructions.h"
39#include "llvm/IR/Metadata.h"
40#include "llvm/IR/Operator.h"
41#include "llvm/Support/AlignOf.h"
42#include "llvm/Support/AtomicOrdering.h"
43#include "llvm/Support/Casting.h"
44#include "llvm/Support/ErrorHandling.h"
45#include "llvm/Support/MachineValueType.h"
46#include "llvm/Support/TypeSize.h"
47#include <algorithm>
48#include <cassert>
49#include <climits>
50#include <cstddef>
51#include <cstdint>
52#include <cstring>
53#include <iterator>
54#include <string>
55#include <tuple>
56
57namespace llvm {
58
59class APInt;
60class Constant;
61template <typename T> struct DenseMapInfo;
62class GlobalValue;
63class MachineBasicBlock;
64class MachineConstantPoolValue;
65class MCSymbol;
66class raw_ostream;
67class SDNode;
68class SelectionDAG;
69class Type;
70class Value;
71
72void checkForCycles(const SDNode *N, const SelectionDAG *DAG = nullptr,
73 bool force = false);
74
75/// This represents a list of ValueType's that has been intern'd by
76/// a SelectionDAG. Instances of this simple value class are returned by
77/// SelectionDAG::getVTList(...).
78///
79struct SDVTList {
80 const EVT *VTs;
81 unsigned int NumVTs;
82};
83
84namespace ISD {
85
86 /// Node predicates
87
88/// If N is a BUILD_VECTOR or SPLAT_VECTOR node whose elements are all the
89/// same constant or undefined, return true and return the constant value in
90/// \p SplatValue.
91bool isConstantSplatVector(const SDNode *N, APInt &SplatValue);
92
93/// Return true if the specified node is a BUILD_VECTOR or SPLAT_VECTOR where
94/// all of the elements are ~0 or undef. If \p BuildVectorOnly is set to
95/// true, it only checks BUILD_VECTOR.
96bool isConstantSplatVectorAllOnes(const SDNode *N,
97 bool BuildVectorOnly = false);
98
99/// Return true if the specified node is a BUILD_VECTOR or SPLAT_VECTOR where
100/// all of the elements are 0 or undef. If \p BuildVectorOnly is set to true, it
101/// only checks BUILD_VECTOR.
102bool isConstantSplatVectorAllZeros(const SDNode *N,
103 bool BuildVectorOnly = false);
104
105/// Return true if the specified node is a BUILD_VECTOR where all of the
106/// elements are ~0 or undef.
107bool isBuildVectorAllOnes(const SDNode *N);
108
109/// Return true if the specified node is a BUILD_VECTOR where all of the
110/// elements are 0 or undef.
111bool isBuildVectorAllZeros(const SDNode *N);
112
113/// Return true if the specified node is a BUILD_VECTOR node of all
114/// ConstantSDNode or undef.
115bool isBuildVectorOfConstantSDNodes(const SDNode *N);
116
117/// Return true if the specified node is a BUILD_VECTOR node of all
118/// ConstantFPSDNode or undef.
119bool isBuildVectorOfConstantFPSDNodes(const SDNode *N);
120
121/// Return true if the node has at least one operand and all operands of the
122/// specified node are ISD::UNDEF.
123bool allOperandsUndef(const SDNode *N);
124
125} // end namespace ISD
126
127//===----------------------------------------------------------------------===//
128/// Unlike LLVM values, Selection DAG nodes may return multiple
129/// values as the result of a computation. Many nodes return multiple values,
130/// from loads (which define a token and a return value) to ADDC (which returns
131/// a result and a carry value), to calls (which may return an arbitrary number
132/// of values).
133///
134/// As such, each use of a SelectionDAG computation must indicate the node that
135/// computes it as well as which return value to use from that node. This pair
136/// of information is represented with the SDValue value type.
137///
138class SDValue {
139 friend struct DenseMapInfo<SDValue>;
140
141 SDNode *Node = nullptr; // The node defining the value we are using.
142 unsigned ResNo = 0; // Which return value of the node we are using.
143
144public:
145 SDValue() = default;
146 SDValue(SDNode *node, unsigned resno);
147
148 /// get the index which selects a specific result in the SDNode
149 unsigned getResNo() const { return ResNo; }
150
151 /// get the SDNode which holds the desired result
152 SDNode *getNode() const { return Node; }
153
154 /// set the SDNode
155 void setNode(SDNode *N) { Node = N; }
156
157 inline SDNode *operator->() const { return Node; }
158
159 bool operator==(const SDValue &O) const {
160 return Node == O.Node && ResNo == O.ResNo;
161 }
162 bool operator!=(const SDValue &O) const {
163 return !operator==(O);
164 }
165 bool operator<(const SDValue &O) const {
166 return std::tie(Node, ResNo) < std::tie(O.Node, O.ResNo);
167 }
168 explicit operator bool() const {
169 return Node != nullptr;
170 }
171
172 SDValue getValue(unsigned R) const {
173 return SDValue(Node, R);
174 }
175
176 /// Return true if this node is an operand of N.
177 bool isOperandOf(const SDNode *N) const;
178
179 /// Return the ValueType of the referenced return value.
180 inline EVT getValueType() const;
181
182 /// Return the simple ValueType of the referenced return value.
183 MVT getSimpleValueType() const {
184 return getValueType().getSimpleVT();
185 }
186
187 /// Returns the size of the value in bits.
188 ///
189 /// If the value type is a scalable vector type, the scalable property will
190 /// be set and the runtime size will be a positive integer multiple of the
191 /// base size.
192 TypeSize getValueSizeInBits() const {
193 return getValueType().getSizeInBits();
194 }
195
196 uint64_t getScalarValueSizeInBits() const {
197 return getValueType().getScalarType().getFixedSizeInBits();
198 }
199
200 // Forwarding methods - These forward to the corresponding methods in SDNode.
201 inline unsigned getOpcode() const;
202 inline unsigned getNumOperands() const;
203 inline const SDValue &getOperand(unsigned i) const;
204 inline uint64_t getConstantOperandVal(unsigned i) const;
205 inline const APInt &getConstantOperandAPInt(unsigned i) const;
206 inline bool isTargetMemoryOpcode() const;
207 inline bool isTargetOpcode() const;
208 inline bool isMachineOpcode() const;
209 inline bool isUndef() const;
210 inline unsigned getMachineOpcode() const;
211 inline const DebugLoc &getDebugLoc() const;
212 inline void dump() const;
213 inline void dump(const SelectionDAG *G) const;
214 inline void dumpr() const;
215 inline void dumpr(const SelectionDAG *G) const;
216
217 /// Return true if this operand (which must be a chain) reaches the
218 /// specified operand without crossing any side-effecting instructions.
219 /// In practice, this looks through token factors and non-volatile loads.
220 /// In order to remain efficient, this only
221 /// looks a couple of nodes in, it does not do an exhaustive search.
222 bool reachesChainWithoutSideEffects(SDValue Dest,
223 unsigned Depth = 2) const;
224
225 /// Return true if there are no nodes using value ResNo of Node.
226 inline bool use_empty() const;
227
228 /// Return true if there is exactly one node using value ResNo of Node.
229 inline bool hasOneUse() const;
230};
231
232template<> struct DenseMapInfo<SDValue> {
233 static inline SDValue getEmptyKey() {
234 SDValue V;
235 V.ResNo = -1U;
236 return V;
237 }
238
239 static inline SDValue getTombstoneKey() {
240 SDValue V;
241 V.ResNo = -2U;
242 return V;
243 }
244
245 static unsigned getHashValue(const SDValue &Val) {
246 return ((unsigned)((uintptr_t)Val.getNode() >> 4) ^
247 (unsigned)((uintptr_t)Val.getNode() >> 9)) + Val.getResNo();
248 }
249
250 static bool isEqual(const SDValue &LHS, const SDValue &RHS) {
251 return LHS == RHS;
252 }
253};
254
255/// Allow casting operators to work directly on
256/// SDValues as if they were SDNode*'s.
257template<> struct simplify_type<SDValue> {
258 using SimpleType = SDNode *;
259
260 static SimpleType getSimplifiedValue(SDValue &Val) {
261 return Val.getNode();
31
←
Returning without writing to 'Val.Node'
→
262 }
263};
264template<> struct simplify_type<const SDValue> {
265 using SimpleType = /*const*/ SDNode *;
266
267 static SimpleType getSimplifiedValue(const SDValue &Val) {
268 return Val.getNode();
269 }
270};
271
272/// Represents a use of a SDNode. This class holds an SDValue,
273/// which records the SDNode being used and the result number, a
274/// pointer to the SDNode using the value, and Next and Prev pointers,
275/// which link together all the uses of an SDNode.
276///
277class SDUse {
278 /// Val - The value being used.
279 SDValue Val;
280 /// User - The user of this value.
281 SDNode *User = nullptr;
282 /// Prev, Next - Pointers to the uses list of the SDNode referred by
283 /// this operand.
284 SDUse **Prev = nullptr;
285 SDUse *Next = nullptr;
286
287public:
288 SDUse() = default;
289 SDUse(const SDUse &U) = delete;
290 SDUse &operator=(const SDUse &) = delete;
291
292 /// Normally SDUse will just implicitly convert to an SDValue that it holds.
293 operator const SDValue&() const { return Val; }
294
295 /// If implicit conversion to SDValue doesn't work, the get() method returns
296 /// the SDValue.
297 const SDValue &get() const { return Val; }
298
299 /// This returns the SDNode that contains this Use.
300 SDNode *getUser() { return User; }
301
302 /// Get the next SDUse in the use list.
303 SDUse *getNext() const { return Next; }
304
305 /// Convenience function for get().getNode().
306 SDNode *getNode() const { return Val.getNode(); }
307 /// Convenience function for get().getResNo().
308 unsigned getResNo() const { return Val.getResNo(); }
309 /// Convenience function for get().getValueType().
310 EVT getValueType() const { return Val.getValueType(); }
311
312 /// Convenience function for get().operator==
313 bool operator==(const SDValue &V) const {
314 return Val == V;
315 }
316
317 /// Convenience function for get().operator!=
318 bool operator!=(const SDValue &V) const {
319 return Val != V;
320 }
321
322 /// Convenience function for get().operator<
323 bool operator<(const SDValue &V) const {
324 return Val < V;
325 }
326
327private:
328 friend class SelectionDAG;
329 friend class SDNode;
330 // TODO: unfriend HandleSDNode once we fix its operand handling.
331 friend class HandleSDNode;
332
333 void setUser(SDNode *p) { User = p; }
334
335 /// Remove this use from its existing use list, assign it the
336 /// given value, and add it to the new value's node's use list.
337 inline void set(const SDValue &V);
338 /// Like set, but only supports initializing a newly-allocated
339 /// SDUse with a non-null value.
340 inline void setInitial(const SDValue &V);
341 /// Like set, but only sets the Node portion of the value,
342 /// leaving the ResNo portion unmodified.
343 inline void setNode(SDNode *N);
344
345 void addToList(SDUse **List) {
346 Next = *List;
347 if (Next) Next->Prev = &Next;
348 Prev = List;
349 *List = this;
350 }
351
352 void removeFromList() {
353 *Prev = Next;
354 if (Next) Next->Prev = Prev;
355 }
356};
357
358/// simplify_type specializations - Allow casting operators to work directly on
359/// SDValues as if they were SDNode*'s.
360template<> struct simplify_type<SDUse> {
361 using SimpleType = SDNode *;
362
363 static SimpleType getSimplifiedValue(SDUse &Val) {
364 return Val.getNode();
365 }
366};
367
368/// These are IR-level optimization flags that may be propagated to SDNodes.
369/// TODO: This data structure should be shared by the IR optimizer and the
370/// the backend.
371struct SDNodeFlags {
372private:
373 bool NoUnsignedWrap : 1;
374 bool NoSignedWrap : 1;
375 bool Exact : 1;
376 bool NoNaNs : 1;
377 bool NoInfs : 1;
378 bool NoSignedZeros : 1;
379 bool AllowReciprocal : 1;
380 bool AllowContract : 1;
381 bool ApproximateFuncs : 1;
382 bool AllowReassociation : 1;
383
384 // We assume instructions do not raise floating-point exceptions by default,
385 // and only those marked explicitly may do so. We could choose to represent
386 // this via a positive "FPExcept" flags like on the MI level, but having a
387 // negative "NoFPExcept" flag here (that defaults to true) makes the flag
388 // intersection logic more straightforward.
389 bool NoFPExcept : 1;
390
391public:
392 /// Default constructor turns off all optimization flags.
393 SDNodeFlags()
394 : NoUnsignedWrap(false), NoSignedWrap(false), Exact(false), NoNaNs(false),
395 NoInfs(false), NoSignedZeros(false), AllowReciprocal(false),
396 AllowContract(false), ApproximateFuncs(false),
397 AllowReassociation(false), NoFPExcept(false) {}
398
399 /// Propagate the fast-math-flags from an IR FPMathOperator.
400 void copyFMF(const FPMathOperator &FPMO) {
401 setNoNaNs(FPMO.hasNoNaNs());
402 setNoInfs(FPMO.hasNoInfs());
403 setNoSignedZeros(FPMO.hasNoSignedZeros());
404 setAllowReciprocal(FPMO.hasAllowReciprocal());
405 setAllowContract(FPMO.hasAllowContract());
406 setApproximateFuncs(FPMO.hasApproxFunc());
407 setAllowReassociation(FPMO.hasAllowReassoc());
408 }
409
410 // These are mutators for each flag.
411 void setNoUnsignedWrap(bool b) { NoUnsignedWrap = b; }
412 void setNoSignedWrap(bool b) { NoSignedWrap = b; }
413 void setExact(bool b) { Exact = b; }
414 void setNoNaNs(bool b) { NoNaNs = b; }
415 void setNoInfs(bool b) { NoInfs = b; }
416 void setNoSignedZeros(bool b) { NoSignedZeros = b; }
417 void setAllowReciprocal(bool b) { AllowReciprocal = b; }
418 void setAllowContract(bool b) { AllowContract = b; }
419 void setApproximateFuncs(bool b) { ApproximateFuncs = b; }
420 void setAllowReassociation(bool b) { AllowReassociation = b; }
421 void setNoFPExcept(bool b) { NoFPExcept = b; }
422
423 // These are accessors for each flag.
424 bool hasNoUnsignedWrap() const { return NoUnsignedWrap; }
425 bool hasNoSignedWrap() const { return NoSignedWrap; }
426 bool hasExact() const { return Exact; }
427 bool hasNoNaNs() const { return NoNaNs; }
428 bool hasNoInfs() const { return NoInfs; }
429 bool hasNoSignedZeros() const { return NoSignedZeros; }
430 bool hasAllowReciprocal() const { return AllowReciprocal; }
431 bool hasAllowContract() const { return AllowContract; }
432 bool hasApproximateFuncs() const { return ApproximateFuncs; }
433 bool hasAllowReassociation() const { return AllowReassociation; }
434 bool hasNoFPExcept() const { return NoFPExcept; }
435
436 /// Clear any flags in this flag set that aren't also set in Flags. All
437 /// flags will be cleared if Flags are undefined.
438 void intersectWith(const SDNodeFlags Flags) {
439 NoUnsignedWrap &= Flags.NoUnsignedWrap;
440 NoSignedWrap &= Flags.NoSignedWrap;
441 Exact &= Flags.Exact;
442 NoNaNs &= Flags.NoNaNs;
443 NoInfs &= Flags.NoInfs;
444 NoSignedZeros &= Flags.NoSignedZeros;
445 AllowReciprocal &= Flags.AllowReciprocal;
446 AllowContract &= Flags.AllowContract;
447 ApproximateFuncs &= Flags.ApproximateFuncs;
448 AllowReassociation &= Flags.AllowReassociation;
449 NoFPExcept &= Flags.NoFPExcept;
450 }
451};
452
453/// Represents one node in the SelectionDAG.
454///
455class SDNode : public FoldingSetNode, public ilist_node<SDNode> {
456private:
457 /// The operation that this node performs.
458 int16_t NodeType;
459
460protected:
461 // We define a set of mini-helper classes to help us interpret the bits in our
462 // SubclassData. These are designed to fit within a uint16_t so they pack
463 // with NodeType.
464
465#if defined(_AIX) && (!defined(__GNUC__4) || defined(__clang__1))
466// Except for GCC; by default, AIX compilers store bit-fields in 4-byte words
467// and give the `pack` pragma push semantics.
468#define BEGIN_TWO_BYTE_PACK() _Pragma("pack(2)")pack(2)
469#define END_TWO_BYTE_PACK() _Pragma("pack(pop)")pack(pop)
470#else
471#define BEGIN_TWO_BYTE_PACK()
472#define END_TWO_BYTE_PACK()
473#endif
474
475BEGIN_TWO_BYTE_PACK()
476 class SDNodeBitfields {
477 friend class SDNode;
478 friend class MemIntrinsicSDNode;
479 friend class MemSDNode;
480 friend class SelectionDAG;
481
482 uint16_t HasDebugValue : 1;
483 uint16_t IsMemIntrinsic : 1;
484 uint16_t IsDivergent : 1;
485 };
486 enum { NumSDNodeBits = 3 };
487
488 class ConstantSDNodeBitfields {
489 friend class ConstantSDNode;
490
491 uint16_t : NumSDNodeBits;
492
493 uint16_t IsOpaque : 1;
494 };
495
496 class MemSDNodeBitfields {
497 friend class MemSDNode;
498 friend class MemIntrinsicSDNode;
499 friend class AtomicSDNode;
500
501 uint16_t : NumSDNodeBits;
502
503 uint16_t IsVolatile : 1;
504 uint16_t IsNonTemporal : 1;
505 uint16_t IsDereferenceable : 1;
506 uint16_t IsInvariant : 1;
507 };
508 enum { NumMemSDNodeBits = NumSDNodeBits + 4 };
509
510 class LSBaseSDNodeBitfields {
511 friend class LSBaseSDNode;
512 friend class MaskedLoadStoreSDNode;
513 friend class MaskedGatherScatterSDNode;
514
515 uint16_t : NumMemSDNodeBits;
516
517 // This storage is shared between disparate class hierarchies to hold an
518 // enumeration specific to the class hierarchy in use.
519 // LSBaseSDNode => enum ISD::MemIndexedMode
520 // MaskedLoadStoreBaseSDNode => enum ISD::MemIndexedMode
521 // MaskedGatherScatterSDNode => enum ISD::MemIndexType
522 uint16_t AddressingMode : 3;
523 };
524 enum { NumLSBaseSDNodeBits = NumMemSDNodeBits + 3 };
525
526 class LoadSDNodeBitfields {
527 friend class LoadSDNode;
528 friend class MaskedLoadSDNode;
529 friend class MaskedGatherSDNode;
530
531 uint16_t : NumLSBaseSDNodeBits;
532
533 uint16_t ExtTy : 2; // enum ISD::LoadExtType
534 uint16_t IsExpanding : 1;
535 };
536
537 class StoreSDNodeBitfields {
538 friend class StoreSDNode;
539 friend class MaskedStoreSDNode;
540 friend class MaskedScatterSDNode;
541
542 uint16_t : NumLSBaseSDNodeBits;
543
544 uint16_t IsTruncating : 1;
545 uint16_t IsCompressing : 1;
546 };
547
548 union {
549 char RawSDNodeBits[sizeof(uint16_t)];
550 SDNodeBitfields SDNodeBits;
551 ConstantSDNodeBitfields ConstantSDNodeBits;
552 MemSDNodeBitfields MemSDNodeBits;
553 LSBaseSDNodeBitfields LSBaseSDNodeBits;
554 LoadSDNodeBitfields LoadSDNodeBits;
555 StoreSDNodeBitfields StoreSDNodeBits;
556 };
557END_TWO_BYTE_PACK()
558#undef BEGIN_TWO_BYTE_PACK
559#undef END_TWO_BYTE_PACK
560
561 // RawSDNodeBits must cover the entirety of the union. This means that all of
562 // the union's members must have size <= RawSDNodeBits. We write the RHS as
563 // "2" instead of sizeof(RawSDNodeBits) because MSVC can't handle the latter.
564 static_assert(sizeof(SDNodeBitfields) <= 2, "field too wide");
565 static_assert(sizeof(ConstantSDNodeBitfields) <= 2, "field too wide");
566 static_assert(sizeof(MemSDNodeBitfields) <= 2, "field too wide");
567 static_assert(sizeof(LSBaseSDNodeBitfields) <= 2, "field too wide");
568 static_assert(sizeof(LoadSDNodeBitfields) <= 2, "field too wide");
569 static_assert(sizeof(StoreSDNodeBitfields) <= 2, "field too wide");
570
571private:
572 friend class SelectionDAG;
573 // TODO: unfriend HandleSDNode once we fix its operand handling.
574 friend class HandleSDNode;
575
576 /// Unique id per SDNode in the DAG.
577 int NodeId = -1;
578
579 /// The values that are used by this operation.
580 SDUse *OperandList = nullptr;
581
582 /// The types of the values this node defines. SDNode's may
583 /// define multiple values simultaneously.
584 const EVT *ValueList;
585
586 /// List of uses for this SDNode.
587 SDUse *UseList = nullptr;
588
589 /// The number of entries in the Operand/Value list.
590 unsigned short NumOperands = 0;
591 unsigned short NumValues;
592
593 // The ordering of the SDNodes. It roughly corresponds to the ordering of the
594 // original LLVM instructions.
595 // This is used for turning off scheduling, because we'll forgo
596 // the normal scheduling algorithms and output the instructions according to
597 // this ordering.
598 unsigned IROrder;
599
600 /// Source line information.
601 DebugLoc debugLoc;
602
603 /// Return a pointer to the specified value type.
604 static const EVT *getValueTypeList(EVT VT);
605
606 SDNodeFlags Flags;
607
608public:
609 /// Unique and persistent id per SDNode in the DAG.
610 /// Used for debug printing.
611 uint16_t PersistentId;
612
613 //===--------------------------------------------------------------------===//
614 // Accessors
615 //
616
617 /// Return the SelectionDAG opcode value for this node. For
618 /// pre-isel nodes (those for which isMachineOpcode returns false), these
619 /// are the opcode values in the ISD and <target>ISD namespaces. For
620 /// post-isel opcodes, see getMachineOpcode.
621 unsigned getOpcode() const { return (unsigned short)NodeType; }
622
623 /// Test if this node has a target-specific opcode (in the
624 /// \<target\>ISD namespace).
625 bool isTargetOpcode() const { return NodeType >= ISD::BUILTIN_OP_END; }
626
627 /// Test if this node has a target-specific opcode that may raise
628 /// FP exceptions (in the \<target\>ISD namespace and greater than
629 /// FIRST_TARGET_STRICTFP_OPCODE). Note that all target memory
630 /// opcode are currently automatically considered to possibly raise
631 /// FP exceptions as well.
632 bool isTargetStrictFPOpcode() const {
633 return NodeType >= ISD::FIRST_TARGET_STRICTFP_OPCODE;
634 }
635
636 /// Test if this node has a target-specific
637 /// memory-referencing opcode (in the \<target\>ISD namespace and
638 /// greater than FIRST_TARGET_MEMORY_OPCODE).
639 bool isTargetMemoryOpcode() const {
640 return NodeType >= ISD::FIRST_TARGET_MEMORY_OPCODE;
641 }
642
643 /// Return true if the type of the node type undefined.
644 bool isUndef() const { return NodeType == ISD::UNDEF; }
645
646 /// Test if this node is a memory intrinsic (with valid pointer information).
647 /// INTRINSIC_W_CHAIN and INTRINSIC_VOID nodes are sometimes created for
648 /// non-memory intrinsics (with chains) that are not really instances of
649 /// MemSDNode. For such nodes, we need some extra state to determine the
650 /// proper classof relationship.
651 bool isMemIntrinsic() const {
652 return (NodeType == ISD::INTRINSIC_W_CHAIN ||
653 NodeType == ISD::INTRINSIC_VOID) &&
654 SDNodeBits.IsMemIntrinsic;
655 }
656
657 /// Test if this node is a strict floating point pseudo-op.
658 bool isStrictFPOpcode() {
659 switch (NodeType) {
660 default:
661 return false;
662 case ISD::STRICT_FP16_TO_FP:
663 case ISD::STRICT_FP_TO_FP16:
664#define DAG_INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC, DAGN) \
665 case ISD::STRICT_##DAGN:
666#include "llvm/IR/ConstrainedOps.def"
667 return true;
668 }
669 }
670
671 /// Test if this node has a post-isel opcode, directly
672 /// corresponding to a MachineInstr opcode.
673 bool isMachineOpcode() const { return NodeType < 0; }
674
675 /// This may only be called if isMachineOpcode returns
676 /// true. It returns the MachineInstr opcode value that the node's opcode
677 /// corresponds to.
678 unsigned getMachineOpcode() const {
679 assert(isMachineOpcode() && "Not a MachineInstr opcode!")((void)0);
680 return ~NodeType;
681 }
682
683 bool getHasDebugValue() const { return SDNodeBits.HasDebugValue; }
684 void setHasDebugValue(bool b) { SDNodeBits.HasDebugValue = b; }
685
686 bool isDivergent() const { return SDNodeBits.IsDivergent; }
687
688 /// Return true if there are no uses of this node.
689 bool use_empty() const { return UseList == nullptr; }
690
691 /// Return true if there is exactly one use of this node.
692 bool hasOneUse() const { return hasSingleElement(uses()); }
693
694 /// Return the number of uses of this node. This method takes
695 /// time proportional to the number of uses.
696 size_t use_size() const { return std::distance(use_begin(), use_end()); }
697
698 /// Return the unique node id.
699 int getNodeId() const { return NodeId; }
700
701 /// Set unique node id.
702 void setNodeId(int Id) { NodeId = Id; }
703
704 /// Return the node ordering.
705 unsigned getIROrder() const { return IROrder; }
706
707 /// Set the node ordering.
708 void setIROrder(unsigned Order) { IROrder = Order; }
709
710 /// Return the source location info.
711 const DebugLoc &getDebugLoc() const { return debugLoc; }
712
713 /// Set source location info. Try to avoid this, putting
714 /// it in the constructor is preferable.
715 void setDebugLoc(DebugLoc dl) { debugLoc = std::move(dl); }
716
717 /// This class provides iterator support for SDUse
718 /// operands that use a specific SDNode.
719 class use_iterator {
720 friend class SDNode;
721
722 SDUse *Op = nullptr;
723
724 explicit use_iterator(SDUse *op) : Op(op) {}
725
726 public:
727 using iterator_category = std::forward_iterator_tag;
728 using value_type = SDUse;
729 using difference_type = std::ptrdiff_t;
730 using pointer = value_type *;
731 using reference = value_type &;
732
733 use_iterator() = default;
734 use_iterator(const use_iterator &I) : Op(I.Op) {}
735
736 bool operator==(const use_iterator &x) const {
737 return Op == x.Op;
738 }
739 bool operator!=(const use_iterator &x) const {
740 return !operator==(x);
741 }
742
743 /// Return true if this iterator is at the end of uses list.
744 bool atEnd() const { return Op == nullptr; }
745
746 // Iterator traversal: forward iteration only.
747 use_iterator &operator++() { // Preincrement
748 assert(Op && "Cannot increment end iterator!")((void)0);
749 Op = Op->getNext();
750 return *this;
751 }
752
753 use_iterator operator++(int) { // Postincrement
754 use_iterator tmp = *this; ++*this; return tmp;
755 }
756
757 /// Retrieve a pointer to the current user node.
758 SDNode *operator*() const {
759 assert(Op && "Cannot dereference end iterator!")((void)0);
760 return Op->getUser();
761 }
762
763 SDNode *operator->() const { return operator*(); }
764
765 SDUse &getUse() const { return *Op; }
766
767 /// Retrieve the operand # of this use in its user.
768 unsigned getOperandNo() const {
769 assert(Op && "Cannot dereference end iterator!")((void)0);
770 return (unsigned)(Op - Op->getUser()->OperandList);
771 }
772 };
773
774 /// Provide iteration support to walk over all uses of an SDNode.
775 use_iterator use_begin() const {
776 return use_iterator(UseList);
777 }
778
779 static use_iterator use_end() { return use_iterator(nullptr); }
780
781 inline iterator_range<use_iterator> uses() {
782 return make_range(use_begin(), use_end());
783 }
784 inline iterator_range<use_iterator> uses() const {
785 return make_range(use_begin(), use_end());
786 }
787
788 /// Return true if there are exactly NUSES uses of the indicated value.
789 /// This method ignores uses of other values defined by this operation.
790 bool hasNUsesOfValue(unsigned NUses, unsigned Value) const;
791
792 /// Return true if there are any use of the indicated value.
793 /// This method ignores uses of other values defined by this operation.
794 bool hasAnyUseOfValue(unsigned Value) const;
795
796 /// Return true if this node is the only use of N.
797 bool isOnlyUserOf(const SDNode *N) const;
798
799 /// Return true if this node is an operand of N.
800 bool isOperandOf(const SDNode *N) const;
801
802 /// Return true if this node is a predecessor of N.
803 /// NOTE: Implemented on top of hasPredecessor and every bit as
804 /// expensive. Use carefully.
805 bool isPredecessorOf(const SDNode *N) const {
806 return N->hasPredecessor(this);
807 }
808
809 /// Return true if N is a predecessor of this node.
810 /// N is either an operand of this node, or can be reached by recursively
811 /// traversing up the operands.
812 /// NOTE: This is an expensive method. Use it carefully.
813 bool hasPredecessor(const SDNode *N) const;
814
815 /// Returns true if N is a predecessor of any node in Worklist. This
816 /// helper keeps Visited and Worklist sets externally to allow unions
817 /// searches to be performed in parallel, caching of results across
818 /// queries and incremental addition to Worklist. Stops early if N is
819 /// found but will resume. Remember to clear Visited and Worklists
820 /// if DAG changes. MaxSteps gives a maximum number of nodes to visit before
821 /// giving up. The TopologicalPrune flag signals that positive NodeIds are
822 /// topologically ordered (Operands have strictly smaller node id) and search
823 /// can be pruned leveraging this.
824 static bool hasPredecessorHelper(const SDNode *N,
825 SmallPtrSetImpl<const SDNode *> &Visited,
826 SmallVectorImpl<const SDNode *> &Worklist,
827 unsigned int MaxSteps = 0,
828 bool TopologicalPrune = false) {
829 SmallVector<const SDNode *, 8> DeferredNodes;
830 if (Visited.count(N))
831 return true;
832
833 // Node Id's are assigned in three places: As a topological
834 // ordering (> 0), during legalization (results in values set to
835 // 0), new nodes (set to -1). If N has a topolgical id then we
836 // know that all nodes with ids smaller than it cannot be
837 // successors and we need not check them. Filter out all node
838 // that can't be matches. We add them to the worklist before exit
839 // in case of multiple calls. Note that during selection the topological id
840 // may be violated if a node's predecessor is selected before it. We mark
841 // this at selection negating the id of unselected successors and
842 // restricting topological pruning to positive ids.
843
844 int NId = N->getNodeId();
845 // If we Invalidated the Id, reconstruct original NId.
846 if (NId < -1)
847 NId = -(NId + 1);
848
849 bool Found = false;
850 while (!Worklist.empty()) {
851 const SDNode *M = Worklist.pop_back_val();
852 int MId = M->getNodeId();
853 if (TopologicalPrune && M->getOpcode() != ISD::TokenFactor && (NId > 0) &&
854 (MId > 0) && (MId < NId)) {
855 DeferredNodes.push_back(M);
856 continue;
857 }
858 for (const SDValue &OpV : M->op_values()) {
859 SDNode *Op = OpV.getNode();
860 if (Visited.insert(Op).second)
861 Worklist.push_back(Op);
862 if (Op == N)
863 Found = true;
864 }
865 if (Found)
866 break;
867 if (MaxSteps != 0 && Visited.size() >= MaxSteps)
868 break;
869 }
870 // Push deferred nodes back on worklist.
871 Worklist.append(DeferredNodes.begin(), DeferredNodes.end());
872 // If we bailed early, conservatively return found.
873 if (MaxSteps != 0 && Visited.size() >= MaxSteps)
874 return true;
875 return Found;
876 }
877
878 /// Return true if all the users of N are contained in Nodes.
879 /// NOTE: Requires at least one match, but doesn't require them all.
880 static bool areOnlyUsersOf(ArrayRef<const SDNode *> Nodes, const SDNode *N);
881
882 /// Return the number of values used by this operation.
883 unsigned getNumOperands() const { return NumOperands; }
884
885 /// Return the maximum number of operands that a SDNode can hold.
886 static constexpr size_t getMaxNumOperands() {
887 return std::numeric_limits<decltype(SDNode::NumOperands)>::max();
888 }
889
890 /// Helper method returns the integer value of a ConstantSDNode operand.
891 inline uint64_t getConstantOperandVal(unsigned Num) const;
892
893 /// Helper method returns the APInt of a ConstantSDNode operand.
894 inline const APInt &getConstantOperandAPInt(unsigned Num) const;
895
896 const SDValue &getOperand(unsigned Num) const {
897 assert(Num < NumOperands && "Invalid child # of SDNode!")((void)0);
898 return OperandList[Num];
899 }
900
901 using op_iterator = SDUse *;
902
903 op_iterator op_begin() const { return OperandList; }
904 op_iterator op_end() const { return OperandList+NumOperands; }
905 ArrayRef<SDUse> ops() const { return makeArrayRef(op_begin(), op_end()); }
906
907 /// Iterator for directly iterating over the operand SDValue's.
908 struct value_op_iterator
909 : iterator_adaptor_base<value_op_iterator, op_iterator,
910 std::random_access_iterator_tag, SDValue,
911 ptrdiff_t, value_op_iterator *,
912 value_op_iterator *> {
913 explicit value_op_iterator(SDUse *U = nullptr)
914 : iterator_adaptor_base(U) {}
915
916 const SDValue &operator*() const { return I->get(); }
917 };
918
919 iterator_range<value_op_iterator> op_values() const {
920 return make_range(value_op_iterator(op_begin()),
921 value_op_iterator(op_end()));
922 }
923
924 SDVTList getVTList() const {
925 SDVTList X = { ValueList, NumValues };
926 return X;
927 }
928
929 /// If this node has a glue operand, return the node
930 /// to which the glue operand points. Otherwise return NULL.
931 SDNode *getGluedNode() const {
932 if (getNumOperands() != 0 &&
933 getOperand(getNumOperands()-1).getValueType() == MVT::Glue)
934 return getOperand(getNumOperands()-1).getNode();
935 return nullptr;
936 }
937
938 /// If this node has a glue value with a user, return
939 /// the user (there is at most one). Otherwise return NULL.
940 SDNode *getGluedUser() const {
941 for (use_iterator UI = use_begin(), UE = use_end(); UI != UE; ++UI)
942 if (UI.getUse().get().getValueType() == MVT::Glue)
943 return *UI;
944 return nullptr;
945 }
946
947 SDNodeFlags getFlags() const { return Flags; }
948 void setFlags(SDNodeFlags NewFlags) { Flags = NewFlags; }
949
950 /// Clear any flags in this node that aren't also set in Flags.
951 /// If Flags is not in a defined state then this has no effect.
952 void intersectFlagsWith(const SDNodeFlags Flags);
953
954 /// Return the number of values defined/returned by this operator.
955 unsigned getNumValues() const { return NumValues; }
956
957 /// Return the type of a specified result.
958 EVT getValueType(unsigned ResNo) const {
959 assert(ResNo < NumValues && "Illegal result number!")((void)0);
960 return ValueList[ResNo];
961 }
962
963 /// Return the type of a specified result as a simple type.
964 MVT getSimpleValueType(unsigned ResNo) const {
965 return getValueType(ResNo).getSimpleVT();
966 }
967
968 /// Returns MVT::getSizeInBits(getValueType(ResNo)).
969 ///
970 /// If the value type is a scalable vector type, the scalable property will
971 /// be set and the runtime size will be a positive integer multiple of the
972 /// base size.
973 TypeSize getValueSizeInBits(unsigned ResNo) const {
974 return getValueType(ResNo).getSizeInBits();
975 }
976
977 using value_iterator = const EVT *;
978
979 value_iterator value_begin() const { return ValueList; }
980 value_iterator value_end() const { return ValueList+NumValues; }
981 iterator_range<value_iterator> values() const {
982 return llvm::make_range(value_begin(), value_end());
983 }
984
985 /// Return the opcode of this operation for printing.
986 std::string getOperationName(const SelectionDAG *G = nullptr) const;
987 static const char* getIndexedModeName(ISD::MemIndexedMode AM);
988 void print_types(raw_ostream &OS, const SelectionDAG *G) const;
989 void print_details(raw_ostream &OS, const SelectionDAG *G) const;
990 void print(raw_ostream &OS, const SelectionDAG *G = nullptr) const;
991 void printr(raw_ostream &OS, const SelectionDAG *G = nullptr) const;
992
993 /// Print a SelectionDAG node and all children down to
994 /// the leaves. The given SelectionDAG allows target-specific nodes
995 /// to be printed in human-readable form. Unlike printr, this will
996 /// print the whole DAG, including children that appear multiple
997 /// times.
998 ///
999 void printrFull(raw_ostream &O, const SelectionDAG *G = nullptr) const;
1000
1001 /// Print a SelectionDAG node and children up to
1002 /// depth "depth." The given SelectionDAG allows target-specific
1003 /// nodes to be printed in human-readable form. Unlike printr, this
1004 /// will print children that appear multiple times wherever they are
1005 /// used.
1006 ///
1007 void printrWithDepth(raw_ostream &O, const SelectionDAG *G = nullptr,
1008 unsigned depth = 100) const;
1009
1010 /// Dump this node, for debugging.
1011 void dump() const;
1012
1013 /// Dump (recursively) this node and its use-def subgraph.
1014 void dumpr() const;
1015
1016 /// Dump this node, for debugging.
1017 /// The given SelectionDAG allows target-specific nodes to be printed
1018 /// in human-readable form.
1019 void dump(const SelectionDAG *G) const;
1020
1021 /// Dump (recursively) this node and its use-def subgraph.
1022 /// The given SelectionDAG allows target-specific nodes to be printed
1023 /// in human-readable form.
1024 void dumpr(const SelectionDAG *G) const;
1025
1026 /// printrFull to dbgs(). The given SelectionDAG allows
1027 /// target-specific nodes to be printed in human-readable form.
1028 /// Unlike dumpr, this will print the whole DAG, including children
1029 /// that appear multiple times.
1030 void dumprFull(const SelectionDAG *G = nullptr) const;
1031
1032 /// printrWithDepth to dbgs(). The given
1033 /// SelectionDAG allows target-specific nodes to be printed in
1034 /// human-readable form. Unlike dumpr, this will print children
1035 /// that appear multiple times wherever they are used.
1036 ///
1037 void dumprWithDepth(const SelectionDAG *G = nullptr,
1038 unsigned depth = 100) const;
1039
1040 /// Gather unique data for the node.
1041 void Profile(FoldingSetNodeID &ID) const;
1042
1043 /// This method should only be used by the SDUse class.
1044 void addUse(SDUse &U) { U.addToList(&UseList); }
1045
1046protected:
1047 static SDVTList getSDVTList(EVT VT) {
1048 SDVTList Ret = { getValueTypeList(VT), 1 };
1049 return Ret;
1050 }
1051
1052 /// Create an SDNode.
1053 ///
1054 /// SDNodes are created without any operands, and never own the operand
1055 /// storage. To add operands, see SelectionDAG::createOperands.
1056 SDNode(unsigned Opc, unsigned Order, DebugLoc dl, SDVTList VTs)
1057 : NodeType(Opc), ValueList(VTs.VTs), NumValues(VTs.NumVTs),
1058 IROrder(Order), debugLoc(std::move(dl)) {
1059 memset(&RawSDNodeBits, 0, sizeof(RawSDNodeBits));
1060 assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor")((void)0);
1061 assert(NumValues == VTs.NumVTs &&((void)0)
1062 "NumValues wasn't wide enough for its operands!")((void)0);
1063 }
1064
1065 /// Release the operands and set this node to have zero operands.
1066 void DropOperands();
1067};
1068
1069/// Wrapper class for IR location info (IR ordering and DebugLoc) to be passed
1070/// into SDNode creation functions.
1071/// When an SDNode is created from the DAGBuilder, the DebugLoc is extracted
1072/// from the original Instruction, and IROrder is the ordinal position of
1073/// the instruction.
1074/// When an SDNode is created after the DAG is being built, both DebugLoc and
1075/// the IROrder are propagated from the original SDNode.
1076/// So SDLoc class provides two constructors besides the default one, one to
1077/// be used by the DAGBuilder, the other to be used by others.
1078class SDLoc {
1079private:
1080 DebugLoc DL;
1081 int IROrder = 0;
1082
1083public:
1084 SDLoc() = default;
1085 SDLoc(const SDNode *N) : DL(N->getDebugLoc()), IROrder(N->getIROrder()) {}
1086 SDLoc(const SDValue V) : SDLoc(V.getNode()) {}
1087 SDLoc(const Instruction *I, int Order) : IROrder(Order) {
1088 assert(Order >= 0 && "bad IROrder")((void)0);
1089 if (I)
1090 DL = I->getDebugLoc();
1091 }
1092
1093 unsigned getIROrder() const { return IROrder; }
1094 const DebugLoc &getDebugLoc() const { return DL; }
1095};
1096
1097// Define inline functions from the SDValue class.
1098
1099inline SDValue::SDValue(SDNode *node, unsigned resno)
1100 : Node(node), ResNo(resno) {
1101 // Explicitly check for !ResNo to avoid use-after-free, because there are
1102 // callers that use SDValue(N, 0) with a deleted N to indicate successful
1103 // combines.
1104 assert((!Node || !ResNo || ResNo < Node->getNumValues()) &&((void)0)
1105 "Invalid result number for the given node!")((void)0);
1106 assert(ResNo < -2U && "Cannot use result numbers reserved for DenseMaps.")((void)0);
1107}
1108
1109inline unsigned SDValue::getOpcode() const {
1110 return Node->getOpcode();
1111}
1112
1113inline EVT SDValue::getValueType() const {
1114 return Node->getValueType(ResNo);
1115}
1116
1117inline unsigned SDValue::getNumOperands() const {
1118 return Node->getNumOperands();
1119}
1120
1121inline const SDValue &SDValue::getOperand(unsigned i) const {
1122 return Node->getOperand(i);
1123}
1124
1125inline uint64_t SDValue::getConstantOperandVal(unsigned i) const {
1126 return Node->getConstantOperandVal(i);
1127}
1128
1129inline const APInt &SDValue::getConstantOperandAPInt(unsigned i) const {
1130 return Node->getConstantOperandAPInt(i);
1131}
1132
1133inline bool SDValue::isTargetOpcode() const {
1134 return Node->isTargetOpcode();
1135}
1136
1137inline bool SDValue::isTargetMemoryOpcode() const {
1138 return Node->isTargetMemoryOpcode();
1139}
1140
1141inline bool SDValue::isMachineOpcode() const {
1142 return Node->isMachineOpcode();
1143}
1144
1145inline unsigned SDValue::getMachineOpcode() const {
1146 return Node->getMachineOpcode();
1147}
1148
1149inline bool SDValue::isUndef() const {
1150 return Node->isUndef();
43
←
Called C++ object pointer is null
1151}
1152
1153inline bool SDValue::use_empty() const {
1154 return !Node->hasAnyUseOfValue(ResNo);
1155}
1156
1157inline bool SDValue::hasOneUse() const {
1158 return Node->hasNUsesOfValue(1, ResNo);
1159}
1160
1161inline const DebugLoc &SDValue::getDebugLoc() const {
1162 return Node->getDebugLoc();
1163}
1164
1165inline void SDValue::dump() const {
1166 return Node->dump();
1167}
1168
1169inline void SDValue::dump(const SelectionDAG *G) const {
1170 return Node->dump(G);
1171}
1172
1173inline void SDValue::dumpr() const {
1174 return Node->dumpr();
1175}
1176
1177inline void SDValue::dumpr(const SelectionDAG *G) const {
1178 return Node->dumpr(G);
1179}
1180
1181// Define inline functions from the SDUse class.
1182
1183inline void SDUse::set(const SDValue &V) {
1184 if (Val.getNode()) removeFromList();
1185 Val = V;
1186 if (V.getNode()) V.getNode()->addUse(*this);
1187}
1188
1189inline void SDUse::setInitial(const SDValue &V) {
1190 Val = V;
1191 V.getNode()->addUse(*this);
1192}
1193
1194inline void SDUse::setNode(SDNode *N) {
1195 if (Val.getNode()) removeFromList();
1196 Val.setNode(N);
1197 if (N) N->addUse(*this);
1198}
1199
1200/// This class is used to form a handle around another node that
1201/// is persistent and is updated across invocations of replaceAllUsesWith on its
1202/// operand. This node should be directly created by end-users and not added to
1203/// the AllNodes list.
1204class HandleSDNode : public SDNode {
1205 SDUse Op;
1206
1207public:
1208 explicit HandleSDNode(SDValue X)
1209 : SDNode(ISD::HANDLENODE, 0, DebugLoc(), getSDVTList(MVT::Other)) {
1210 // HandleSDNodes are never inserted into the DAG, so they won't be
1211 // auto-numbered. Use ID 65535 as a sentinel.
1212 PersistentId = 0xffff;
1213
1214 // Manually set up the operand list. This node type is special in that it's
1215 // always stack allocated and SelectionDAG does not manage its operands.
1216 // TODO: This should either (a) not be in the SDNode hierarchy, or (b) not
1217 // be so special.
1218 Op.setUser(this);
1219 Op.setInitial(X);
1220 NumOperands = 1;
1221 OperandList = &Op;
1222 }
1223 ~HandleSDNode();
1224
1225 const SDValue &getValue() const { return Op; }
1226};
1227
1228class AddrSpaceCastSDNode : public SDNode {
1229private:
1230 unsigned SrcAddrSpace;
1231 unsigned DestAddrSpace;
1232
1233public:
1234 AddrSpaceCastSDNode(unsigned Order, const DebugLoc &dl, EVT VT,
1235 unsigned SrcAS, unsigned DestAS);
1236
1237 unsigned getSrcAddressSpace() const { return SrcAddrSpace; }
1238 unsigned getDestAddressSpace() const { return DestAddrSpace; }
1239
1240 static bool classof(const SDNode *N) {
1241 return N->getOpcode() == ISD::ADDRSPACECAST;
1242 }
1243};
1244
1245/// This is an abstract virtual class for memory operations.
1246class MemSDNode : public SDNode {
1247private:
1248 // VT of in-memory value.
1249 EVT MemoryVT;
1250
1251protected:
1252 /// Memory reference information.
1253 MachineMemOperand *MMO;
1254
1255public:
1256 MemSDNode(unsigned Opc, unsigned Order, const DebugLoc &dl, SDVTList VTs,
1257 EVT memvt, MachineMemOperand *MMO);
1258
1259 bool readMem() const { return MMO->isLoad(); }
1260 bool writeMem() const { return MMO->isStore(); }
1261
1262 /// Returns alignment and volatility of the memory access
1263 Align getOriginalAlign() const { return MMO->getBaseAlign(); }
1264 Align getAlign() const { return MMO->getAlign(); }
1265 // FIXME: Remove once transition to getAlign is over.
1266 unsigned getAlignment() const { return MMO->getAlign().value(); }
1267
1268 /// Return the SubclassData value, without HasDebugValue. This contains an
1269 /// encoding of the volatile flag, as well as bits used by subclasses. This
1270 /// function should only be used to compute a FoldingSetNodeID value.
1271 /// The HasDebugValue bit is masked out because CSE map needs to match
1272 /// nodes with debug info with nodes without debug info. Same is about
1273 /// isDivergent bit.
1274 unsigned getRawSubclassData() const {
1275 uint16_t Data;
1276 union {
1277 char RawSDNodeBits[sizeof(uint16_t)];
1278 SDNodeBitfields SDNodeBits;
1279 };
1280 memcpy(&RawSDNodeBits, &this->RawSDNodeBits, sizeof(this->RawSDNodeBits));
1281 SDNodeBits.HasDebugValue = 0;
1282 SDNodeBits.IsDivergent = false;
1283 memcpy(&Data, &RawSDNodeBits, sizeof(RawSDNodeBits));
1284 return Data;
1285 }
1286
1287 bool isVolatile() const { return MemSDNodeBits.IsVolatile; }
1288 bool isNonTemporal() const { return MemSDNodeBits.IsNonTemporal; }
1289 bool isDereferenceable() const { return MemSDNodeBits.IsDereferenceable; }
1290 bool isInvariant() const { return MemSDNodeBits.IsInvariant; }
1291
1292 // Returns the offset from the location of the access.
1293 int64_t getSrcValueOffset() const { return MMO->getOffset(); }
1294
1295 /// Returns the AA info that describes the dereference.
1296 AAMDNodes getAAInfo() const { return MMO->getAAInfo(); }
1297
1298 /// Returns the Ranges that describes the dereference.
1299 const MDNode *getRanges() const { return MMO->getRanges(); }
1300
1301 /// Returns the synchronization scope ID for this memory operation.
1302 SyncScope::ID getSyncScopeID() const { return MMO->getSyncScopeID(); }
1303
1304 /// Return the atomic ordering requirements for this memory operation. For
1305 /// cmpxchg atomic operations, return the atomic ordering requirements when
1306 /// store occurs.
1307 AtomicOrdering getSuccessOrdering() const {
1308 return MMO->getSuccessOrdering();
1309 }
1310
1311 /// Return a single atomic ordering that is at least as strong as both the
1312 /// success and failure orderings for an atomic operation. (For operations
1313 /// other than cmpxchg, this is equivalent to getSuccessOrdering().)
1314 AtomicOrdering getMergedOrdering() const { return MMO->getMergedOrdering(); }
1315
1316 /// Return true if the memory operation ordering is Unordered or higher.
1317 bool isAtomic() const { return MMO->isAtomic(); }
1318
1319 /// Returns true if the memory operation doesn't imply any ordering
1320 /// constraints on surrounding memory operations beyond the normal memory
1321 /// aliasing rules.
1322 bool isUnordered() const { return MMO->isUnordered(); }
1323
1324 /// Returns true if the memory operation is neither atomic or volatile.
1325 bool isSimple() const { return !isAtomic() && !isVolatile(); }
1326
1327 /// Return the type of the in-memory value.
1328 EVT getMemoryVT() const { return MemoryVT; }
1329
1330 /// Return a MachineMemOperand object describing the memory
1331 /// reference performed by operation.
1332 MachineMemOperand *getMemOperand() const { return MMO; }
1333
1334 const MachinePointerInfo &getPointerInfo() const {
1335 return MMO->getPointerInfo();
1336 }
1337
1338 /// Return the address space for the associated pointer
1339 unsigned getAddressSpace() const {
1340 return getPointerInfo().getAddrSpace();
1341 }
1342
1343 /// Update this MemSDNode's MachineMemOperand information
1344 /// to reflect the alignment of NewMMO, if it has a greater alignment.
1345 /// This must only be used when the new alignment applies to all users of
1346 /// this MachineMemOperand.
1347 void refineAlignment(const MachineMemOperand *NewMMO) {
1348 MMO->refineAlignment(NewMMO);
1349 }
1350
1351 const SDValue &getChain() const { return getOperand(0); }
1352
1353 const SDValue &getBasePtr() const {
1354 switch (getOpcode()) {
1355 case ISD::STORE:
1356 case ISD::MSTORE:
1357 return getOperand(2);
1358 case ISD::MGATHER:
1359 case ISD::MSCATTER:
1360 return getOperand(3);
1361 default:
1362 return getOperand(1);
1363 }
1364 }
1365
1366 // Methods to support isa and dyn_cast
1367 static bool classof(const SDNode *N) {
1368 // For some targets, we lower some target intrinsics to a MemIntrinsicNode
1369 // with either an intrinsic or a target opcode.
1370 switch (N->getOpcode()) {
1371 case ISD::LOAD:
1372 case ISD::STORE:
1373 case ISD::PREFETCH:
1374 case ISD::ATOMIC_CMP_SWAP:
1375 case ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS:
1376 case ISD::ATOMIC_SWAP:
1377 case ISD::ATOMIC_LOAD_ADD:
1378 case ISD::ATOMIC_LOAD_SUB:
1379 case ISD::ATOMIC_LOAD_AND:
1380 case ISD::ATOMIC_LOAD_CLR:
1381 case ISD::ATOMIC_LOAD_OR:
1382 case ISD::ATOMIC_LOAD_XOR:
1383 case ISD::ATOMIC_LOAD_NAND:
1384 case ISD::ATOMIC_LOAD_MIN:
1385 case ISD::ATOMIC_LOAD_MAX:
1386 case ISD::ATOMIC_LOAD_UMIN:
1387 case ISD::ATOMIC_LOAD_UMAX:
1388 case ISD::ATOMIC_LOAD_FADD:
1389 case ISD::ATOMIC_LOAD_FSUB:
1390 case ISD::ATOMIC_LOAD:
1391 case ISD::ATOMIC_STORE:
1392 case ISD::MLOAD:
1393 case ISD::MSTORE:
1394 case ISD::MGATHER:
1395 case ISD::MSCATTER:
1396 return true;
1397 default:
1398 return N->isMemIntrinsic() || N->isTargetMemoryOpcode();
1399 }
1400 }
1401};
1402
1403/// This is an SDNode representing atomic operations.
1404class AtomicSDNode : public MemSDNode {
1405public:
1406 AtomicSDNode(unsigned Opc, unsigned Order, const DebugLoc &dl, SDVTList VTL,
1407 EVT MemVT, MachineMemOperand *MMO)
1408 : MemSDNode(Opc, Order, dl, VTL, MemVT, MMO) {
1409 assert(((Opc != ISD::ATOMIC_LOAD && Opc != ISD::ATOMIC_STORE) ||((void)0)
1410 MMO->isAtomic()) && "then why are we using an AtomicSDNode?")((void)0);
1411 }
1412
1413 const SDValue &getBasePtr() const { return getOperand(1); }
1414 const SDValue &getVal() const { return getOperand(2); }
1415
1416 /// Returns true if this SDNode represents cmpxchg atomic operation, false
1417 /// otherwise.
1418 bool isCompareAndSwap() const {
1419 unsigned Op = getOpcode();
1420 return Op == ISD::ATOMIC_CMP_SWAP ||
1421 Op == ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS;
1422 }
1423
1424 /// For cmpxchg atomic operations, return the atomic ordering requirements
1425 /// when store does not occur.
1426 AtomicOrdering getFailureOrdering() const {
1427 assert(isCompareAndSwap() && "Must be cmpxchg operation")((void)0);
1428 return MMO->getFailureOrdering();
1429 }
1430
1431 // Methods to support isa and dyn_cast
1432 static bool classof(const SDNode *N) {
1433 return N->getOpcode() == ISD::ATOMIC_CMP_SWAP ||
1434 N->getOpcode() == ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS ||
1435 N->getOpcode() == ISD::ATOMIC_SWAP ||
1436 N->getOpcode() == ISD::ATOMIC_LOAD_ADD ||
1437 N->getOpcode() == ISD::ATOMIC_LOAD_SUB ||
1438 N->getOpcode() == ISD::ATOMIC_LOAD_AND ||
1439 N->getOpcode() == ISD::ATOMIC_LOAD_CLR ||
1440 N->getOpcode() == ISD::ATOMIC_LOAD_OR ||
1441 N->getOpcode() == ISD::ATOMIC_LOAD_XOR ||
1442 N->getOpcode() == ISD::ATOMIC_LOAD_NAND ||
1443 N->getOpcode() == ISD::ATOMIC_LOAD_MIN ||
1444 N->getOpcode() == ISD::ATOMIC_LOAD_MAX ||
1445 N->getOpcode() == ISD::ATOMIC_LOAD_UMIN ||
1446 N->getOpcode() == ISD::ATOMIC_LOAD_UMAX ||
1447 N->getOpcode() == ISD::ATOMIC_LOAD_FADD ||
1448 N->getOpcode() == ISD::ATOMIC_LOAD_FSUB ||
1449 N->getOpcode() == ISD::ATOMIC_LOAD ||
1450 N->getOpcode() == ISD::ATOMIC_STORE;
1451 }
1452};
1453
1454/// This SDNode is used for target intrinsics that touch
1455/// memory and need an associated MachineMemOperand. Its opcode may be
1456/// INTRINSIC_VOID, INTRINSIC_W_CHAIN, PREFETCH, or a target-specific opcode
1457/// with a value not less than FIRST_TARGET_MEMORY_OPCODE.
1458class MemIntrinsicSDNode : public MemSDNode {
1459public:
1460 MemIntrinsicSDNode(unsigned Opc, unsigned Order, const DebugLoc &dl,
1461 SDVTList VTs, EVT MemoryVT, MachineMemOperand *MMO)
1462 : MemSDNode(Opc, Order, dl, VTs, MemoryVT, MMO) {
1463 SDNodeBits.IsMemIntrinsic = true;
1464 }
1465
1466 // Methods to support isa and dyn_cast
1467 static bool classof(const SDNode *N) {
1468 // We lower some target intrinsics to their target opcode
1469 // early a node with a target opcode can be of this class
1470 return N->isMemIntrinsic() ||
1471 N->getOpcode() == ISD::PREFETCH ||
1472 N->isTargetMemoryOpcode();
1473 }
1474};
1475
1476/// This SDNode is used to implement the code generator
1477/// support for the llvm IR shufflevector instruction. It combines elements
1478/// from two input vectors into a new input vector, with the selection and
1479/// ordering of elements determined by an array of integers, referred to as
1480/// the shuffle mask. For input vectors of width N, mask indices of 0..N-1
1481/// refer to elements from the LHS input, and indices from N to 2N-1 the RHS.
1482/// An index of -1 is treated as undef, such that the code generator may put
1483/// any value in the corresponding element of the result.
1484class ShuffleVectorSDNode : public SDNode {
1485 // The memory for Mask is owned by the SelectionDAG's OperandAllocator, and
1486 // is freed when the SelectionDAG object is destroyed.
1487 const int *Mask;
1488
1489protected:
1490 friend class SelectionDAG;
1491
1492 ShuffleVectorSDNode(EVT VT, unsigned Order, const DebugLoc &dl, const int *M)
1493 : SDNode(ISD::VECTOR_SHUFFLE, Order, dl, getSDVTList(VT)), Mask(M) {}
1494
1495public:
1496 ArrayRef<int> getMask() const {
1497 EVT VT = getValueType(0);
1498 return makeArrayRef(Mask, VT.getVectorNumElements());
1499 }
1500
1501 int getMaskElt(unsigned Idx) const {
1502 assert(Idx < getValueType(0).getVectorNumElements() && "Idx out of range!")((void)0);
1503 return Mask[Idx];
1504 }
1505
1506 bool isSplat() const { return isSplatMask(Mask, getValueType(0)); }
1507
1508 int getSplatIndex() const {
1509 assert(isSplat() && "Cannot get splat index for non-splat!")((void)0);
1510 EVT VT = getValueType(0);
1511 for (unsigned i = 0, e = VT.getVectorNumElements(); i != e; ++i)
1512 if (Mask[i] >= 0)
1513 return Mask[i];
1514
1515 // We can choose any index value here and be correct because all elements
1516 // are undefined. Return 0 for better potential for callers to simplify.
1517 return 0;
1518 }
1519
1520 static bool isSplatMask(const int *Mask, EVT VT);
1521
1522 /// Change values in a shuffle permute mask assuming
1523 /// the two vector operands have swapped position.
1524 static void commuteMask(MutableArrayRef<int> Mask) {
1525 unsigned NumElems = Mask.size();
1526 for (unsigned i = 0; i != NumElems; ++i) {
1527 int idx = Mask[i];
1528 if (idx < 0)
1529 continue;
1530 else if (idx < (int)NumElems)
1531 Mask[i] = idx + NumElems;
1532 else
1533 Mask[i] = idx - NumElems;
1534 }
1535 }
1536
1537 static bool classof(const SDNode *N) {
1538 return N->getOpcode() == ISD::VECTOR_SHUFFLE;
1539 }
1540};
1541
1542class ConstantSDNode : public SDNode {
1543 friend class SelectionDAG;
1544
1545 const ConstantInt *Value;
1546
1547 ConstantSDNode(bool isTarget, bool isOpaque, const ConstantInt *val, EVT VT)
1548 : SDNode(isTarget ? ISD::TargetConstant : ISD::Constant, 0, DebugLoc(),
1549 getSDVTList(VT)),
1550 Value(val) {
1551 ConstantSDNodeBits.IsOpaque = isOpaque;
1552 }
1553
1554public:
1555 const ConstantInt *getConstantIntValue() const { return Value; }
1556 const APInt &getAPIntValue() const { return Value->getValue(); }
1557 uint64_t getZExtValue() const { return Value->getZExtValue(); }
1558 int64_t getSExtValue() const { return Value->getSExtValue(); }
1559 uint64_t getLimitedValue(uint64_t Limit = UINT64_MAX0xffffffffffffffffULL) {
1560 return Value->getLimitedValue(Limit);
1561 }
1562 MaybeAlign getMaybeAlignValue() const { return Value->getMaybeAlignValue(); }
1563 Align getAlignValue() const { return Value->getAlignValue(); }
1564
1565 bool isOne() const { return Value->isOne(); }
1566 bool isNullValue() const { return Value->isZero(); }
1567 bool isAllOnesValue() const { return Value->isMinusOne(); }
1568 bool isMaxSignedValue() const { return Value->isMaxValue(true); }
1569 bool isMinSignedValue() const { return Value->isMinValue(true); }
1570
1571 bool isOpaque() const { return ConstantSDNodeBits.IsOpaque; }
1572
1573 static bool classof(const SDNode *N) {
1574 return N->getOpcode() == ISD::Constant ||
1575 N->getOpcode() == ISD::TargetConstant;
1576 }
1577};
1578
1579uint64_t SDNode::getConstantOperandVal(unsigned Num) const {
1580 return cast<ConstantSDNode>(getOperand(Num))->getZExtValue();
1581}
1582
1583const APInt &SDNode::getConstantOperandAPInt(unsigned Num) const {
1584 return cast<ConstantSDNode>(getOperand(Num))->getAPIntValue();
1585}
1586
1587class ConstantFPSDNode : public SDNode {
1588 friend class SelectionDAG;
1589
1590 const ConstantFP *Value;
1591
1592 ConstantFPSDNode(bool isTarget, const ConstantFP *val, EVT VT)
1593 : SDNode(isTarget ? ISD::TargetConstantFP : ISD::ConstantFP, 0,
1594 DebugLoc(), getSDVTList(VT)),
1595 Value(val) {}
1596
1597public:
1598 const APFloat& getValueAPF() const { return Value->getValueAPF(); }
1599 const ConstantFP *getConstantFPValue() const { return Value; }
1600
1601 /// Return true if the value is positive or negative zero.
1602 bool isZero() const { return Value->isZero(); }
1603
1604 /// Return true if the value is a NaN.
1605 bool isNaN() const { return Value->isNaN(); }
1606
1607 /// Return true if the value is an infinity
1608 bool isInfinity() const { return Value->isInfinity(); }
1609
1610 /// Return true if the value is negative.
1611 bool isNegative() const { return Value->isNegative(); }
1612
1613 /// We don't rely on operator== working on double values, as
1614 /// it returns true for things that are clearly not equal, like -0.0 and 0.0.
1615 /// As such, this method can be used to do an exact bit-for-bit comparison of
1616 /// two floating point values.
1617
1618 /// We leave the version with the double argument here because it's just so
1619 /// convenient to write "2.0" and the like. Without this function we'd
1620 /// have to duplicate its logic everywhere it's called.
1621 bool isExactlyValue(double V) const {
1622 return Value->getValueAPF().isExactlyValue(V);
1623 }
1624 bool isExactlyValue(const APFloat& V) const;
1625
1626 static bool isValueValidForType(EVT VT, const APFloat& Val);
1627
1628 static bool classof(const SDNode *N) {
1629 return N->getOpcode() == ISD::ConstantFP ||
1630 N->getOpcode() == ISD::TargetConstantFP;
1631 }
1632};
1633
1634/// Returns true if \p V is a constant integer zero.
1635bool isNullConstant(SDValue V);
1636
1637/// Returns true if \p V is an FP constant with a value of positive zero.
1638bool isNullFPConstant(SDValue V);
1639
1640/// Returns true if \p V is an integer constant with all bits set.
1641bool isAllOnesConstant(SDValue V);
1642
1643/// Returns true if \p V is a constant integer one.
1644bool isOneConstant(SDValue V);
1645
1646/// Return the non-bitcasted source operand of \p V if it exists.
1647/// If \p V is not a bitcasted value, it is returned as-is.
1648SDValue peekThroughBitcasts(SDValue V);
1649
1650/// Return the non-bitcasted and one-use source operand of \p V if it exists.
1651/// If \p V is not a bitcasted one-use value, it is returned as-is.
1652SDValue peekThroughOneUseBitcasts(SDValue V);
1653
1654/// Return the non-extracted vector source operand of \p V if it exists.
1655/// If \p V is not an extracted subvector, it is returned as-is.
1656SDValue peekThroughExtractSubvectors(SDValue V);
1657
1658/// Returns true if \p V is a bitwise not operation. Assumes that an all ones
1659/// constant is canonicalized to be operand 1.
1660bool isBitwiseNot(SDValue V, bool AllowUndefs = false);
1661
1662/// Returns the SDNode if it is a constant splat BuildVector or constant int.
1663ConstantSDNode *isConstOrConstSplat(SDValue N, bool AllowUndefs = false,
1664 bool AllowTruncation = false);
1665
1666/// Returns the SDNode if it is a demanded constant splat BuildVector or
1667/// constant int.
1668ConstantSDNode *isConstOrConstSplat(SDValue N, const APInt &DemandedElts,
1669 bool AllowUndefs = false,
1670 bool AllowTruncation = false);
1671
1672/// Returns the SDNode if it is a constant splat BuildVector or constant float.
1673ConstantFPSDNode *isConstOrConstSplatFP(SDValue N, bool AllowUndefs = false);
1674
1675/// Returns the SDNode if it is a demanded constant splat BuildVector or
1676/// constant float.
1677ConstantFPSDNode *isConstOrConstSplatFP(SDValue N, const APInt &DemandedElts,
1678 bool AllowUndefs = false);
1679
1680/// Return true if the value is a constant 0 integer or a splatted vector of
1681/// a constant 0 integer (with no undefs by default).
1682/// Build vector implicit truncation is not an issue for null values.
1683bool isNullOrNullSplat(SDValue V, bool AllowUndefs = false);
1684
1685/// Return true if the value is a constant 1 integer or a splatted vector of a
1686/// constant 1 integer (with no undefs).
1687/// Does not permit build vector implicit truncation.
1688bool isOneOrOneSplat(SDValue V, bool AllowUndefs = false);
1689
1690/// Return true if the value is a constant -1 integer or a splatted vector of a
1691/// constant -1 integer (with no undefs).
1692/// Does not permit build vector implicit truncation.
1693bool isAllOnesOrAllOnesSplat(SDValue V, bool AllowUndefs = false);
1694
1695/// Return true if \p V is either a integer or FP constant.
1696inline bool isIntOrFPConstant(SDValue V) {
1697 return isa<ConstantSDNode>(V) || isa<ConstantFPSDNode>(V);
1698}
1699
1700class GlobalAddressSDNode : public SDNode {
1701 friend class SelectionDAG;
1702
1703 const GlobalValue *TheGlobal;
1704 int64_t Offset;
1705 unsigned TargetFlags;
1706
1707 GlobalAddressSDNode(unsigned Opc, unsigned Order, const DebugLoc &DL,
1708 const GlobalValue *GA, EVT VT, int64_t o,
1709 unsigned TF);
1710
1711public:
1712 const GlobalValue *getGlobal() const { return TheGlobal; }
1713 int64_t getOffset() const { return Offset; }
1714 unsigned getTargetFlags() const { return TargetFlags; }
1715 // Return the address space this GlobalAddress belongs to.
1716 unsigned getAddressSpace() const;
1717
1718 static bool classof(const SDNode *N) {
1719 return N->getOpcode() == ISD::GlobalAddress ||
1720 N->getOpcode() == ISD::TargetGlobalAddress ||
1721 N->getOpcode() == ISD::GlobalTLSAddress ||
1722 N->getOpcode() == ISD::TargetGlobalTLSAddress;
1723 }
1724};
1725
1726class FrameIndexSDNode : public SDNode {
1727 friend class SelectionDAG;
1728
1729 int FI;
1730
1731 FrameIndexSDNode(int fi, EVT VT, bool isTarg)
1732 : SDNode(isTarg ? ISD::TargetFrameIndex : ISD::FrameIndex,
1733 0, DebugLoc(), getSDVTList(VT)), FI(fi) {
1734 }
1735
1736public:
1737 int getIndex() const { return FI; }
1738
1739 static bool classof(const SDNode *N) {
1740 return N->getOpcode() == ISD::FrameIndex ||
1741 N->getOpcode() == ISD::TargetFrameIndex;
1742 }
1743};
1744
1745/// This SDNode is used for LIFETIME_START/LIFETIME_END values, which indicate
1746/// the offet and size that are started/ended in the underlying FrameIndex.
1747class LifetimeSDNode : public SDNode {
1748 friend class SelectionDAG;
1749 int64_t Size;
1750 int64_t Offset; // -1 if offset is unknown.
1751
1752 LifetimeSDNode(unsigned Opcode, unsigned Order, const DebugLoc &dl,
1753 SDVTList VTs, int64_t Size, int64_t Offset)
1754 : SDNode(Opcode, Order, dl, VTs), Size(Size), Offset(Offset) {}
1755public:
1756 int64_t getFrameIndex() const {
1757 return cast<FrameIndexSDNode>(getOperand(1))->getIndex();
1758 }
1759
1760 bool hasOffset() const { return Offset >= 0; }
1761 int64_t getOffset() const {
1762 assert(hasOffset() && "offset is unknown")((void)0);
1763 return Offset;
1764 }
1765 int64_t getSize() const {
1766 assert(hasOffset() && "offset is unknown")((void)0);
1767 return Size;
1768 }
1769
1770 // Methods to support isa and dyn_cast
1771 static bool classof(const SDNode *N) {
1772 return N->getOpcode() == ISD::LIFETIME_START ||
1773 N->getOpcode() == ISD::LIFETIME_END;
1774 }
1775};
1776
1777/// This SDNode is used for PSEUDO_PROBE values, which are the function guid and
1778/// the index of the basic block being probed. A pseudo probe serves as a place
1779/// holder and will be removed at the end of compilation. It does not have any
1780/// operand because we do not want the instruction selection to deal with any.
1781class PseudoProbeSDNode : public SDNode {
1782 friend class SelectionDAG;
1783 uint64_t Guid;
1784 uint64_t Index;
1785 uint32_t Attributes;
1786
1787 PseudoProbeSDNode(unsigned Opcode, unsigned Order, const DebugLoc &Dl,
1788 SDVTList VTs, uint64_t Guid, uint64_t Index, uint32_t Attr)
1789 : SDNode(Opcode, Order, Dl, VTs), Guid(Guid), Index(Index),
1790 Attributes(Attr) {}
1791
1792public:
1793 uint64_t getGuid() const { return Guid; }
1794 uint64_t getIndex() const { return Index; }
1795 uint32_t getAttributes() const { return Attributes; }
1796
1797 // Methods to support isa and dyn_cast
1798 static bool classof(const SDNode *N) {
1799 return N->getOpcode() == ISD::PSEUDO_PROBE;
1800 }
1801};
1802
1803class JumpTableSDNode : public SDNode {
1804 friend class SelectionDAG;
1805
1806 int JTI;
1807 unsigned TargetFlags;
1808
1809 JumpTableSDNode(int jti, EVT VT, bool isTarg, unsigned TF)
1810 : SDNode(isTarg ? ISD::TargetJumpTable : ISD::JumpTable,
1811 0, DebugLoc(), getSDVTList(VT)), JTI(jti), TargetFlags(TF) {
1812 }
1813
1814public:
1815 int getIndex() const { return JTI; }
1816 unsigned getTargetFlags() const { return TargetFlags; }
1817
1818 static bool classof(const SDNode *N) {
1819 return N->getOpcode() == ISD::JumpTable ||
1820 N->getOpcode() == ISD::TargetJumpTable;
1821 }
1822};
1823
1824class ConstantPoolSDNode : public SDNode {
1825 friend class SelectionDAG;
1826
1827 union {
1828 const Constant *ConstVal;
1829 MachineConstantPoolValue *MachineCPVal;
1830 } Val;
1831 int Offset; // It's a MachineConstantPoolValue if top bit is set.
1832 Align Alignment; // Minimum alignment requirement of CP.
1833 unsigned TargetFlags;
1834
1835 ConstantPoolSDNode(bool isTarget, const Constant *c, EVT VT, int o,
1836 Align Alignment, unsigned TF)
1837 : SDNode(isTarget ? ISD::TargetConstantPool : ISD::ConstantPool, 0,
1838 DebugLoc(), getSDVTList(VT)),
1839 Offset(o), Alignment(Alignment), TargetFlags(TF) {
1840 assert(Offset >= 0 && "Offset is too large")((void)0);
1841 Val.ConstVal = c;
1842 }
1843
1844 ConstantPoolSDNode(bool isTarget, MachineConstantPoolValue *v, EVT VT, int o,
1845 Align Alignment, unsigned TF)
1846 : SDNode(isTarget ? ISD::TargetConstantPool : ISD::ConstantPool, 0,
1847 DebugLoc(), getSDVTList(VT)),
1848 Offset(o), Alignment(Alignment), TargetFlags(TF) {
1849 assert(Offset >= 0 && "Offset is too large")((void)0);
1850 Val.MachineCPVal = v;
1851 Offset |= 1 << (sizeof(unsigned)*CHAR_BIT8-1);
1852 }
1853
1854public:
1855 bool isMachineConstantPoolEntry() const {
1856 return Offset < 0;
1857 }
1858
1859 const Constant *getConstVal() const {
1860 assert(!isMachineConstantPoolEntry() && "Wrong constantpool type")((void)0);
1861 return Val.ConstVal;
1862 }
1863
1864 MachineConstantPoolValue *getMachineCPVal() const {
1865 assert(isMachineConstantPoolEntry() && "Wrong constantpool type")((void)0);
1866 return Val.MachineCPVal;
1867 }
1868
1869 int getOffset() const {
1870 return Offset & ~(1 << (sizeof(unsigned)*CHAR_BIT8-1));
1871 }
1872
1873 // Return the alignment of this constant pool object, which is either 0 (for
1874 // default alignment) or the desired value.
1875 Align getAlign() const { return Alignment; }
1876 unsigned getTargetFlags() const { return TargetFlags; }
1877
1878 Type *getType() const;
1879
1880 static bool classof(const SDNode *N) {
1881 return N->getOpcode() == ISD::ConstantPool ||
1882 N->getOpcode() == ISD::TargetConstantPool;
1883 }
1884};
1885
1886/// Completely target-dependent object reference.
1887class TargetIndexSDNode : public SDNode {
1888 friend class SelectionDAG;
1889
1890 unsigned TargetFlags;
1891 int Index;
1892 int64_t Offset;
1893
1894public:
1895 TargetIndexSDNode(int Idx, EVT VT, int64_t Ofs, unsigned TF)
1896 : SDNode(ISD::TargetIndex, 0, DebugLoc(), getSDVTList(VT)),
1897 TargetFlags(TF), Index(Idx), Offset(Ofs) {}
1898
1899 unsigned getTargetFlags() const { return TargetFlags; }
1900 int getIndex() const { return Index; }
1901 int64_t getOffset() const { return Offset; }
1902
1903 static bool classof(const SDNode *N) {
1904 return N->getOpcode() == ISD::TargetIndex;
1905 }
1906};
1907
1908class BasicBlockSDNode : public SDNode {
1909 friend class SelectionDAG;
1910
1911 MachineBasicBlock *MBB;
1912
1913 /// Debug info is meaningful and potentially useful here, but we create
1914 /// blocks out of order when they're jumped to, which makes it a bit
1915 /// harder. Let's see if we need it first.
1916 explicit BasicBlockSDNode(MachineBasicBlock *mbb)
1917 : SDNode(ISD::BasicBlock, 0, DebugLoc(), getSDVTList(MVT::Other)), MBB(mbb)
1918 {}
1919
1920public:
1921 MachineBasicBlock *getBasicBlock() const { return MBB; }
1922
1923 static bool classof(const SDNode *N) {
1924 return N->getOpcode() == ISD::BasicBlock;
1925 }
1926};
1927
1928/// A "pseudo-class" with methods for operating on BUILD_VECTORs.
1929class BuildVectorSDNode : public SDNode {
1930public:
1931 // These are constructed as SDNodes and then cast to BuildVectorSDNodes.
1932 explicit BuildVectorSDNode() = delete;
1933
1934 /// Check if this is a constant splat, and if so, find the
1935 /// smallest element size that splats the vector. If MinSplatBits is
1936 /// nonzero, the element size must be at least that large. Note that the
1937 /// splat element may be the entire vector (i.e., a one element vector).
1938 /// Returns the splat element value in SplatValue. Any undefined bits in
1939 /// that value are zero, and the corresponding bits in the SplatUndef mask
1940 /// are set. The SplatBitSize value is set to the splat element size in
1941 /// bits. HasAnyUndefs is set to true if any bits in the vector are
1942 /// undefined. isBigEndian describes the endianness of the target.
1943 bool isConstantSplat(APInt &SplatValue, APInt &SplatUndef,
1944 unsigned &SplatBitSize, bool &HasAnyUndefs,
1945 unsigned MinSplatBits = 0,
1946 bool isBigEndian = false) const;
1947
1948 /// Returns the demanded splatted value or a null value if this is not a
1949 /// splat.
1950 ///
1951 /// The DemandedElts mask indicates the elements that must be in the splat.
1952 /// If passed a non-null UndefElements bitvector, it will resize it to match
1953 /// the vector width and set the bits where elements are undef.
1954 SDValue getSplatValue(const APInt &DemandedElts,
1955 BitVector *UndefElements = nullptr) const;
1956
1957 /// Returns the splatted value or a null value if this is not a splat.
1958 ///
1959 /// If passed a non-null UndefElements bitvector, it will resize it to match
1960 /// the vector width and set the bits where elements are undef.
1961 SDValue getSplatValue(BitVector *UndefElements = nullptr) const;
1962
1963 /// Find the shortest repeating sequence of values in the build vector.
1964 ///
1965 /// e.g. { u, X, u, X, u, u, X, u } -> { X }
1966 /// { X, Y, u, Y, u, u, X, u } -> { X, Y }
1967 ///
1968 /// Currently this must be a power-of-2 build vector.
1969 /// The DemandedElts mask indicates the elements that must be present,
1970 /// undemanded elements in Sequence may be null (SDValue()). If passed a
1971 /// non-null UndefElements bitvector, it will resize it to match the original
1972 /// vector width and set the bits where elements are undef. If result is
1973 /// false, Sequence will be empty.
1974 bool getRepeatedSequence(const APInt &DemandedElts,
1975 SmallVectorImpl<SDValue> &Sequence,
1976 BitVector *UndefElements = nullptr) const;
1977
1978 /// Find the shortest repeating sequence of values in the build vector.
1979 ///
1980 /// e.g. { u, X, u, X, u, u, X, u } -> { X }
1981 /// { X, Y, u, Y, u, u, X, u } -> { X, Y }
1982 ///
1983 /// Currently this must be a power-of-2 build vector.
1984 /// If passed a non-null UndefElements bitvector, it will resize it to match
1985 /// the original vector width and set the bits where elements are undef.
1986 /// If result is false, Sequence will be empty.
1987 bool getRepeatedSequence(SmallVectorImpl<SDValue> &Sequence,
1988 BitVector *UndefElements = nullptr) const;
1989
1990 /// Returns the demanded splatted constant or null if this is not a constant
1991 /// splat.
1992 ///
1993 /// The DemandedElts mask indicates the elements that must be in the splat.
1994 /// If passed a non-null UndefElements bitvector, it will resize it to match
1995 /// the vector width and set the bits where elements are undef.
1996 ConstantSDNode *
1997 getConstantSplatNode(const APInt &DemandedElts,
1998 BitVector *UndefElements = nullptr) const;
1999
2000 /// Returns the splatted constant or null if this is not a constant
2001 /// splat.
2002 ///
2003 /// If passed a non-null UndefElements bitvector, it will resize it to match
2004 /// the vector width and set the bits where elements are undef.
2005 ConstantSDNode *
2006 getConstantSplatNode(BitVector *UndefElements = nullptr) const;
2007
2008 /// Returns the demanded splatted constant FP or null if this is not a
2009 /// constant FP splat.
2010 ///
2011 /// The DemandedElts mask indicates the elements that must be in the splat.
2012 /// If passed a non-null UndefElements bitvector, it will resize it to match
2013 /// the vector width and set the bits where elements are undef.
2014 ConstantFPSDNode *
2015 getConstantFPSplatNode(const APInt &DemandedElts,
2016 BitVector *UndefElements = nullptr) const;
2017
2018 /// Returns the splatted constant FP or null if this is not a constant
2019 /// FP splat.
2020 ///
2021 /// If passed a non-null UndefElements bitvector, it will resize it to match
2022 /// the vector width and set the bits where elements are undef.
2023 ConstantFPSDNode *
2024 getConstantFPSplatNode(BitVector *UndefElements = nullptr) const;
2025
2026 /// If this is a constant FP splat and the splatted constant FP is an
2027 /// exact power or 2, return the log base 2 integer value. Otherwise,
2028 /// return -1.
2029 ///
2030 /// The BitWidth specifies the necessary bit precision.
2031 int32_t getConstantFPSplatPow2ToLog2Int(BitVector *UndefElements,
2032 uint32_t BitWidth) const;
2033
2034 bool isConstant() const;
2035
2036 static bool classof(const SDNode *N) {
2037 return N->getOpcode() == ISD::BUILD_VECTOR;
2038 }
2039};
2040
2041/// An SDNode that holds an arbitrary LLVM IR Value. This is
2042/// used when the SelectionDAG needs to make a simple reference to something
2043/// in the LLVM IR representation.
2044///
2045class SrcValueSDNode : public SDNode {
2046 friend class SelectionDAG;
2047
2048 const Value *V;
2049
2050 /// Create a SrcValue for a general value.
2051 explicit SrcValueSDNode(const Value *v)
2052 : SDNode(ISD::SRCVALUE, 0, DebugLoc(), getSDVTList(MVT::Other)), V(v) {}
2053
2054public:
2055 /// Return the contained Value.
2056 const Value *getValue() const { return V; }
2057
2058 static bool classof(const SDNode *N) {
2059 return N->getOpcode() == ISD::SRCVALUE;
2060 }
2061};
2062
2063class MDNodeSDNode : public SDNode {
2064 friend class SelectionDAG;
2065
2066 const MDNode *MD;
2067
2068 explicit MDNodeSDNode(const MDNode *md)
2069 : SDNode(ISD::MDNODE_SDNODE, 0, DebugLoc(), getSDVTList(MVT::Other)), MD(md)
2070 {}
2071
2072public:
2073 const MDNode *getMD() const { return MD; }
2074
2075 static bool classof(const SDNode *N) {
2076 return N->getOpcode() == ISD::MDNODE_SDNODE;
2077 }
2078};
2079
2080class RegisterSDNode : public SDNode {
2081 friend class SelectionDAG;
2082
2083 Register Reg;
2084
2085 RegisterSDNode(Register reg, EVT VT)
2086 : SDNode(ISD::Register, 0, DebugLoc(), getSDVTList(VT)), Reg(reg) {}
2087
2088public:
2089 Register getReg() const { return Reg; }
2090
2091 static bool classof(const SDNode *N) {
2092 return N->getOpcode() == ISD::Register;
2093 }
2094};
2095
2096class RegisterMaskSDNode : public SDNode {
2097 friend class SelectionDAG;
2098
2099 // The memory for RegMask is not owned by the node.
2100 const uint32_t *RegMask;
2101
2102 RegisterMaskSDNode(const uint32_t *mask)
2103 : SDNode(ISD::RegisterMask, 0, DebugLoc(), getSDVTList(MVT::Untyped)),
2104 RegMask(mask) {}
2105
2106public:
2107 const uint32_t *getRegMask() const { return RegMask; }
2108
2109 static bool classof(const SDNode *N) {
2110 return N->getOpcode() == ISD::RegisterMask;
2111 }
2112};
2113
2114class BlockAddressSDNode : public SDNode {
2115 friend class SelectionDAG;
2116
2117 const BlockAddress *BA;
2118 int64_t Offset;
2119 unsigned TargetFlags;
2120
2121 BlockAddressSDNode(unsigned NodeTy, EVT VT, const BlockAddress *ba,
2122 int64_t o, unsigned Flags)
2123 : SDNode(NodeTy, 0, DebugLoc(), getSDVTList(VT)),
2124 BA(ba), Offset(o), TargetFlags(Flags) {}
2125
2126public:
2127 const BlockAddress *getBlockAddress() const { return BA; }
2128 int64_t getOffset() const { return Offset; }
2129 unsigned getTargetFlags() const { return TargetFlags; }
2130
2131 static bool classof(const SDNode *N) {
2132 return N->getOpcode() == ISD::BlockAddress ||
2133 N->getOpcode() == ISD::TargetBlockAddress;
2134 }
2135};
2136
2137class LabelSDNode : public SDNode {
2138 friend class SelectionDAG;
2139
2140 MCSymbol *Label;
2141
2142 LabelSDNode(unsigned Opcode, unsigned Order, const DebugLoc &dl, MCSymbol *L)
2143 : SDNode(Opcode, Order, dl, getSDVTList(MVT::Other)), Label(L) {
2144 assert(LabelSDNode::classof(this) && "not a label opcode")((void)0);
2145 }
2146
2147public:
2148 MCSymbol *getLabel() const { return Label; }
2149
2150 static bool classof(const SDNode *N) {
2151 return N->getOpcode() == ISD::EH_LABEL ||
2152 N->getOpcode() == ISD::ANNOTATION_LABEL;
2153 }
2154};
2155
2156class ExternalSymbolSDNode : public SDNode {
2157 friend class SelectionDAG;
2158
2159 const char *Symbol;
2160 unsigned TargetFlags;
2161
2162 ExternalSymbolSDNode(bool isTarget, const char *Sym, unsigned TF, EVT VT)
2163 : SDNode(isTarget ? ISD::TargetExternalSymbol : ISD::ExternalSymbol, 0,
2164 DebugLoc(), getSDVTList(VT)),
2165 Symbol(Sym), TargetFlags(TF) {}
2166
2167public:
2168 const char *getSymbol() const { return Symbol; }
2169 unsigned getTargetFlags() const { return TargetFlags; }
2170
2171 static bool classof(const SDNode *N) {
2172 return N->getOpcode() == ISD::ExternalSymbol ||
2173 N->getOpcode() == ISD::TargetExternalSymbol;
2174 }
2175};
2176
2177class MCSymbolSDNode : public SDNode {
2178 friend class SelectionDAG;
2179
2180 MCSymbol *Symbol;
2181
2182 MCSymbolSDNode(MCSymbol *Symbol, EVT VT)
2183 : SDNode(ISD::MCSymbol, 0, DebugLoc(), getSDVTList(VT)), Symbol(Symbol) {}
2184
2185public:
2186 MCSymbol *getMCSymbol() const { return Symbol; }
2187
2188 static bool classof(const SDNode *N) {
2189 return N->getOpcode() == ISD::MCSymbol;
2190 }
2191};
2192
2193class CondCodeSDNode : public SDNode {
2194 friend class SelectionDAG;
2195
2196 ISD::CondCode Condition;
2197
2198 explicit CondCodeSDNode(ISD::CondCode Cond)
2199 : SDNode(ISD::CONDCODE, 0, DebugLoc(), getSDVTList(MVT::Other)),
2200 Condition(Cond) {}
2201
2202public:
2203 ISD::CondCode get() const { return Condition; }
2204
2205 static bool classof(const SDNode *N) {
2206 return N->getOpcode() == ISD::CONDCODE;
2207 }
2208};
2209
2210/// This class is used to represent EVT's, which are used
2211/// to parameterize some operations.
2212class VTSDNode : public SDNode {
2213 friend class SelectionDAG;
2214
2215 EVT ValueType;
2216
2217 explicit VTSDNode(EVT VT)
2218 : SDNode(ISD::VALUETYPE, 0, DebugLoc(), getSDVTList(MVT::Other)),
2219 ValueType(VT) {}
2220
2221public:
2222 EVT getVT() const { return ValueType; }
2223
2224 static bool classof(const SDNode *N) {
2225 return N->getOpcode() == ISD::VALUETYPE;
2226 }
2227};
2228
2229/// Base class for LoadSDNode and StoreSDNode
2230class LSBaseSDNode : public MemSDNode {
2231public:
2232 LSBaseSDNode(ISD::NodeType NodeTy, unsigned Order, const DebugLoc &dl,
2233 SDVTList VTs, ISD::MemIndexedMode AM, EVT MemVT,
2234 MachineMemOperand *MMO)
2235 : MemSDNode(NodeTy, Order, dl, VTs, MemVT, MMO) {
2236 LSBaseSDNodeBits.AddressingMode = AM;
2237 assert(getAddressingMode() == AM && "Value truncated")((void)0);
2238 }
2239
2240 const SDValue &getOffset() const {
2241 return getOperand(getOpcode() == ISD::LOAD ? 2 : 3);
2242 }
2243
2244 /// Return the addressing mode for this load or store:
2245 /// unindexed, pre-inc, pre-dec, post-inc, or post-dec.
2246 ISD::MemIndexedMode getAddressingMode() const {
2247 return static_cast<ISD::MemIndexedMode>(LSBaseSDNodeBits.AddressingMode);
2248 }
2249
2250 /// Return true if this is a pre/post inc/dec load/store.
2251 bool isIndexed() const { return getAddressingMode() != ISD::UNINDEXED; }
2252
2253 /// Return true if this is NOT a pre/post inc/dec load/store.
2254 bool isUnindexed() const { return getAddressingMode() == ISD::UNINDEXED; }
2255
2256 static bool classof(const SDNode *N) {
2257 return N->getOpcode() == ISD::LOAD ||
2258 N->getOpcode() == ISD::STORE;
2259 }
2260};
2261
2262/// This class is used to represent ISD::LOAD nodes.
2263class LoadSDNode : public LSBaseSDNode {
2264 friend class SelectionDAG;
2265
2266 LoadSDNode(unsigned Order, const DebugLoc &dl, SDVTList VTs,
2267 ISD::MemIndexedMode AM, ISD::LoadExtType ETy, EVT MemVT,
2268 MachineMemOperand *MMO)
2269 : LSBaseSDNode(ISD::LOAD, Order, dl, VTs, AM, MemVT, MMO) {
2270 LoadSDNodeBits.ExtTy = ETy;
2271 assert(readMem() && "Load MachineMemOperand is not a load!")((void)0);
2272 assert(!writeMem() && "Load MachineMemOperand is a store!")((void)0);
2273 }
2274
2275public:
2276 /// Return whether this is a plain node,
2277 /// or one of the varieties of value-extending loads.
2278 ISD::LoadExtType getExtensionType() const {
2279 return static_cast<ISD::LoadExtType>(LoadSDNodeBits.ExtTy);
2280 }
2281
2282 const SDValue &getBasePtr() const { return getOperand(1); }
2283 const SDValue &getOffset() const { return getOperand(2); }
2284
2285 static bool classof(const SDNode *N) {
2286 return N->getOpcode() == ISD::LOAD;
2287 }
2288};
2289
2290/// This class is used to represent ISD::STORE nodes.
2291class StoreSDNode : public LSBaseSDNode {
2292 friend class SelectionDAG;
2293
2294 StoreSDNode(unsigned Order, const DebugLoc &dl, SDVTList VTs,
2295 ISD::MemIndexedMode AM, bool isTrunc, EVT MemVT,
2296 MachineMemOperand *MMO)
2297 : LSBaseSDNode(ISD::STORE, Order, dl, VTs, AM, MemVT, MMO) {
2298 StoreSDNodeBits.IsTruncating = isTrunc;
2299 assert(!readMem() && "Store MachineMemOperand is a load!")((void)0);
2300 assert(writeMem() && "Store MachineMemOperand is not a store!")((void)0);
2301 }
2302
2303public:
2304 /// Return true if the op does a truncation before store.
2305 /// For integers this is the same as doing a TRUNCATE and storing the result.
2306 /// For floats, it is the same as doing an FP_ROUND and storing the result.
2307 bool isTruncatingStore() const { return StoreSDNodeBits.IsTruncating; }
2308 void setTruncatingStore(bool Truncating) {
2309 StoreSDNodeBits.IsTruncating = Truncating;
2310 }
2311
2312 const SDValue &getValue() const { return getOperand(1); }
2313 const SDValue &getBasePtr() const { return getOperand(2); }
2314 const SDValue &getOffset() const { return getOperand(3); }
2315
2316 static bool classof(const SDNode *N) {
2317 return N->getOpcode() == ISD::STORE;
2318 }
2319};
2320
2321/// This base class is used to represent MLOAD and MSTORE nodes
2322class MaskedLoadStoreSDNode : public MemSDNode {
2323public:
2324 friend class SelectionDAG;
2325
2326 MaskedLoadStoreSDNode(ISD::NodeType NodeTy, unsigned Order,
2327 const DebugLoc &dl, SDVTList VTs,
2328 ISD::MemIndexedMode AM, EVT MemVT,
2329 MachineMemOperand *MMO)
2330 : MemSDNode(NodeTy, Order, dl, VTs, MemVT, MMO) {
2331 LSBaseSDNodeBits.AddressingMode = AM;
2332 assert(getAddressingMode() == AM && "Value truncated")((void)0);
2333 }
2334
2335 // MaskedLoadSDNode (Chain, ptr, offset, mask, passthru)
2336 // MaskedStoreSDNode (Chain, data, ptr, offset, mask)
2337 // Mask is a vector of i1 elements
2338 const SDValue &getOffset() const {
2339 return getOperand(getOpcode() == ISD::MLOAD ? 2 : 3);
2340 }
2341 const SDValue &getMask() const {
2342 return getOperand(getOpcode() == ISD::MLOAD ? 3 : 4);
2343 }
2344
2345 /// Return the addressing mode for this load or store:
2346 /// unindexed, pre-inc, pre-dec, post-inc, or post-dec.
2347 ISD::MemIndexedMode getAddressingMode() const {
2348 return static_cast<ISD::MemIndexedMode>(LSBaseSDNodeBits.AddressingMode);
2349 }
2350
2351 /// Return true if this is a pre/post inc/dec load/store.
2352 bool isIndexed() const { return getAddressingMode() != ISD::UNINDEXED; }
2353
2354 /// Return true if this is NOT a pre/post inc/dec load/store.
2355 bool isUnindexed() const { return getAddressingMode() == ISD::UNINDEXED; }
2356
2357 static bool classof(const SDNode *N) {
2358 return N->getOpcode() == ISD::MLOAD ||
2359 N->getOpcode() == ISD::MSTORE;
2360 }
2361};
2362
2363/// This class is used to represent an MLOAD node
2364class MaskedLoadSDNode : public MaskedLoadStoreSDNode {
2365public:
2366 friend class SelectionDAG;
2367
2368 MaskedLoadSDNode(unsigned Order, const DebugLoc &dl, SDVTList VTs,
2369 ISD::MemIndexedMode AM, ISD::LoadExtType ETy,
2370 bool IsExpanding, EVT MemVT, MachineMemOperand *MMO)
2371 : MaskedLoadStoreSDNode(ISD::MLOAD, Order, dl, VTs, AM, MemVT, MMO) {
2372 LoadSDNodeBits.ExtTy = ETy;
2373 LoadSDNodeBits.IsExpanding = IsExpanding;
2374 }
2375
2376 ISD::LoadExtType getExtensionType() const {
2377 return static_cast<ISD::LoadExtType>(LoadSDNodeBits.ExtTy);
2378 }
2379
2380 const SDValue &getBasePtr() const { return getOperand(1); }
2381 const SDValue &getOffset() const { return getOperand(2); }
2382 const SDValue &getMask() const { return getOperand(3); }
2383 const SDValue &getPassThru() const { return getOperand(4); }
2384
2385 static bool classof(const SDNode *N) {
2386 return N->getOpcode() == ISD::MLOAD;
2387 }
2388
2389 bool isExpandingLoad() const { return LoadSDNodeBits.IsExpanding; }
2390};
2391
2392/// This class is used to represent an MSTORE node
2393class MaskedStoreSDNode : public MaskedLoadStoreSDNode {
2394public:
2395 friend class SelectionDAG;
2396
2397 MaskedStoreSDNode(unsigned Order, const DebugLoc &dl, SDVTList VTs,
2398 ISD::MemIndexedMode AM, bool isTrunc, bool isCompressing,
2399 EVT MemVT, MachineMemOperand *MMO)
2400 : MaskedLoadStoreSDNode(ISD::MSTORE, Order, dl, VTs, AM, MemVT, MMO) {
2401 StoreSDNodeBits.IsTruncating = isTrunc;
2402 StoreSDNodeBits.IsCompressing = isCompressing;
2403 }
2404
2405 /// Return true if the op does a truncation before store.
2406 /// For integers this is the same as doing a TRUNCATE and storing the result.
2407 /// For floats, it is the same as doing an FP_ROUND and storing the result.
2408 bool isTruncatingStore() const { return StoreSDNodeBits.IsTruncating; }
2409
2410 /// Returns true if the op does a compression to the vector before storing.
2411 /// The node contiguously stores the active elements (integers or floats)
2412 /// in src (those with their respective bit set in writemask k) to unaligned
2413 /// memory at base_addr.
2414 bool isCompressingStore() const { return StoreSDNodeBits.IsCompressing; }
2415
2416 const SDValue &getValue() const { return getOperand(1); }
2417 const SDValue &getBasePtr() const { return getOperand(2); }
2418 const SDValue &getOffset() const { return getOperand(3); }
2419 const SDValue &getMask() const { return getOperand(4); }
2420
2421 static bool classof(const SDNode *N) {
2422 return N->getOpcode() == ISD::MSTORE;
2423 }
2424};
2425
2426/// This is a base class used to represent
2427/// MGATHER and MSCATTER nodes
2428///
2429class MaskedGatherScatterSDNode : public MemSDNode {
2430public:
2431 friend class SelectionDAG;
2432
2433 MaskedGatherScatterSDNode(ISD::NodeType NodeTy, unsigned Order,
2434 const DebugLoc &dl, SDVTList VTs, EVT MemVT,
2435 MachineMemOperand *MMO, ISD::MemIndexType IndexType)
2436 : MemSDNode(NodeTy, Order, dl, VTs, MemVT, MMO) {
2437 LSBaseSDNodeBits.AddressingMode = IndexType;
2438 assert(getIndexType() == IndexType && "Value truncated")((void)0);
2439 }
2440
2441 /// How is Index applied to BasePtr when computing addresses.
2442 ISD::MemIndexType getIndexType() const {
2443 return static_cast<ISD::MemIndexType>(LSBaseSDNodeBits.AddressingMode);
2444 }
2445 void setIndexType(ISD::MemIndexType IndexType) {
2446 LSBaseSDNodeBits.AddressingMode = IndexType;
2447 }
2448 bool isIndexScaled() const {
2449 return (getIndexType() == ISD::SIGNED_SCALED) ||
2450 (getIndexType() == ISD::UNSIGNED_SCALED);
2451 }
2452 bool isIndexSigned() const {
2453 return (getIndexType() == ISD::SIGNED_SCALED) ||
2454 (getIndexType() == ISD::SIGNED_UNSCALED);
2455 }
2456
2457 // In the both nodes address is Op1, mask is Op2:
2458 // MaskedGatherSDNode (Chain, passthru, mask, base, index, scale)
2459 // MaskedScatterSDNode (Chain, value, mask, base, index, scale)
2460 // Mask is a vector of i1 elements
2461 const SDValue &getBasePtr() const { return getOperand(3); }
2462 const SDValue &getIndex() const { return getOperand(4); }
2463 const SDValue &getMask() const { return getOperand(2); }
2464 const SDValue &getScale() const { return getOperand(5); }
2465
2466 static bool classof(const SDNode *N) {
2467 return N->getOpcode() == ISD::MGATHER ||
2468 N->getOpcode() == ISD::MSCATTER;
2469 }
2470};
2471
2472/// This class is used to represent an MGATHER node
2473///
2474class MaskedGatherSDNode : public MaskedGatherScatterSDNode {
2475public:
2476 friend class SelectionDAG;
2477
2478 MaskedGatherSDNode(unsigned Order, const DebugLoc &dl, SDVTList VTs,
2479 EVT MemVT, MachineMemOperand *MMO,
2480 ISD::MemIndexType IndexType, ISD::LoadExtType ETy)
2481 : MaskedGatherScatterSDNode(ISD::MGATHER, Order, dl, VTs, MemVT, MMO,
2482 IndexType) {
2483 LoadSDNodeBits.ExtTy = ETy;
2484 }
2485
2486 const SDValue &getPassThru() const { return getOperand(1); }
2487
2488 ISD::LoadExtType getExtensionType() const {
2489 return ISD::LoadExtType(LoadSDNodeBits.ExtTy);
2490 }
2491
2492 static bool classof(const SDNode *N) {
2493 return N->getOpcode() == ISD::MGATHER;
2494 }
2495};
2496
2497/// This class is used to represent an MSCATTER node
2498///
2499class MaskedScatterSDNode : public MaskedGatherScatterSDNode {
2500public:
2501 friend class SelectionDAG;
2502
2503 MaskedScatterSDNode(unsigned Order, const DebugLoc &dl, SDVTList VTs,
2504 EVT MemVT, MachineMemOperand *MMO,
2505 ISD::MemIndexType IndexType, bool IsTrunc)
2506 : MaskedGatherScatterSDNode(ISD::MSCATTER, Order, dl, VTs, MemVT, MMO,
2507 IndexType) {
2508 StoreSDNodeBits.IsTruncating = IsTrunc;
2509 }
2510
2511 /// Return true if the op does a truncation before store.
2512 /// For integers this is the same as doing a TRUNCATE and storing the result.
2513 /// For floats, it is the same as doing an FP_ROUND and storing the result.
2514 bool isTruncatingStore() const { return StoreSDNodeBits.IsTruncating; }
2515
2516 const SDValue &getValue() const { return getOperand(1); }
2517
2518 static bool classof(const SDNode *N) {
2519 return N->getOpcode() == ISD::MSCATTER;
2520 }
2521};
2522
2523/// An SDNode that represents everything that will be needed
2524/// to construct a MachineInstr. These nodes are created during the
2525/// instruction selection proper phase.
2526///
2527/// Note that the only supported way to set the `memoperands` is by calling the
2528/// `SelectionDAG::setNodeMemRefs` function as the memory management happens
2529/// inside the DAG rather than in the node.
2530class MachineSDNode : public SDNode {
2531private:
2532 friend class SelectionDAG;
2533
2534 MachineSDNode(unsigned Opc, unsigned Order, const DebugLoc &DL, SDVTList VTs)
2535 : SDNode(Opc, Order, DL, VTs) {}
2536
2537 // We use a pointer union between a single `MachineMemOperand` pointer and
2538 // a pointer to an array of `MachineMemOperand` pointers. This is null when
2539 // the number of these is zero, the single pointer variant used when the
2540 // number is one, and the array is used for larger numbers.
2541 //
2542 // The array is allocated via the `SelectionDAG`'s allocator and so will
2543 // always live until the DAG is cleaned up and doesn't require ownership here.
2544 //
2545 // We can't use something simpler like `TinyPtrVector` here because `SDNode`
2546 // subclasses aren't managed in a conforming C++ manner. See the comments on
2547 // `SelectionDAG::MorphNodeTo` which details what all goes on, but the
2548 // constraint here is that these don't manage memory with their constructor or
2549 // destructor and can be initialized to a good state even if they start off
2550 // uninitialized.
2551 PointerUnion<MachineMemOperand *, MachineMemOperand **> MemRefs = {};
2552
2553 // Note that this could be folded into the above `MemRefs` member if doing so
2554 // is advantageous at some point. We don't need to store this in most cases.
2555 // However, at the moment this doesn't appear to make the allocation any
2556 // smaller and makes the code somewhat simpler to read.
2557 int NumMemRefs = 0;
2558
2559public:
2560 using mmo_iterator = ArrayRef<MachineMemOperand *>::const_iterator;
2561
2562 ArrayRef<MachineMemOperand *> memoperands() const {
2563 // Special case the common cases.
2564 if (NumMemRefs == 0)
2565 return {};
2566 if (NumMemRefs == 1)
2567 return makeArrayRef(MemRefs.getAddrOfPtr1(), 1);
2568
2569 // Otherwise we have an actual array.
2570 return makeArrayRef(MemRefs.get<MachineMemOperand **>(), NumMemRefs);
2571 }
2572 mmo_iterator memoperands_begin() const { return memoperands().begin(); }
2573 mmo_iterator memoperands_end() const { return memoperands().end(); }
2574 bool memoperands_empty() const { return memoperands().empty(); }
2575
2576 /// Clear out the memory reference descriptor list.
2577 void clearMemRefs() {
2578 MemRefs = nullptr;
2579 NumMemRefs = 0;
2580 }
2581
2582 static bool classof(const SDNode *N) {
2583 return N->isMachineOpcode();
2584 }
2585};
2586
2587/// An SDNode that records if a register contains a value that is guaranteed to
2588/// be aligned accordingly.
2589class AssertAlignSDNode : public SDNode {
2590 Align Alignment;
2591
2592public:
2593 AssertAlignSDNode(unsigned Order, const DebugLoc &DL, EVT VT, Align A)
2594 : SDNode(ISD::AssertAlign, Order, DL, getSDVTList(VT)), Alignment(A) {}
2595
2596 Align getAlign() const { return Alignment; }
2597
2598 static bool classof(const SDNode *N) {
2599 return N->getOpcode() == ISD::AssertAlign;
2600 }
2601};
2602
2603class SDNodeIterator {
2604 const SDNode *Node;
2605 unsigned Operand;
2606
2607 SDNodeIterator(const SDNode *N, unsigned Op) : Node(N), Operand(Op) {}
2608
2609public:
2610 using iterator_category = std::forward_iterator_tag;
2611 using value_type = SDNode;
2612 using difference_type = std::ptrdiff_t;
2613 using pointer = value_type *;
2614 using reference = value_type &;
2615
2616 bool operator==(const SDNodeIterator& x) const {
2617 return Operand == x.Operand;
2618 }
2619 bool operator!=(const SDNodeIterator& x) const { return !operator==(x); }
2620
2621 pointer operator*() const {
2622 return Node->getOperand(Operand).getNode();
2623 }
2624 pointer operator->() const { return operator*(); }
2625
2626 SDNodeIterator& operator++() { // Preincrement
2627 ++Operand;
2628 return *this;
2629 }
2630 SDNodeIterator operator++(int) { // Postincrement
2631 SDNodeIterator tmp = *this; ++*this; return tmp;
2632 }
2633 size_t operator-(SDNodeIterator Other) const {
2634 assert(Node == Other.Node &&((void)0)
2635 "Cannot compare iterators of two different nodes!")((void)0);
2636 return Operand - Other.Operand;
2637 }
2638
2639 static SDNodeIterator begin(const SDNode *N) { return SDNodeIterator(N, 0); }
2640 static SDNodeIterator end (const SDNode *N) {
2641 return SDNodeIterator(N, N->getNumOperands());
2642 }
2643
2644 unsigned getOperand() const { return Operand; }
2645 const SDNode *getNode() const { return Node; }
2646};
2647
2648template <> struct GraphTraits<SDNode*> {
2649 using NodeRef = SDNode *;
2650 using ChildIteratorType = SDNodeIterator;
2651
2652 static NodeRef getEntryNode(SDNode *N) { return N; }
2653
2654 static ChildIteratorType child_begin(NodeRef N) {
2655 return SDNodeIterator::begin(N);
2656 }
2657
2658 static ChildIteratorType child_end(NodeRef N) {
2659 return SDNodeIterator::end(N);
2660 }
2661};
2662
2663/// A representation of the largest SDNode, for use in sizeof().
2664///
2665/// This needs to be a union because the largest node differs on 32 bit systems
2666/// with 4 and 8 byte pointer alignment, respectively.
2667using LargestSDNode = AlignedCharArrayUnion<AtomicSDNode, TargetIndexSDNode,
2668 BlockAddressSDNode,
2669 GlobalAddressSDNode,
2670 PseudoProbeSDNode>;
2671
2672/// The SDNode class with the greatest alignment requirement.
2673using MostAlignedSDNode = GlobalAddressSDNode;
2674
2675namespace ISD {
2676
2677 /// Returns true if the specified node is a non-extending and unindexed load.
2678 inline bool isNormalLoad(const SDNode *N) {
2679 const LoadSDNode *Ld = dyn_cast<LoadSDNode>(N);
2680 return Ld && Ld->getExtensionType() == ISD::NON_EXTLOAD &&
2681 Ld->getAddressingMode() == ISD::UNINDEXED;
2682 }
2683
2684 /// Returns true if the specified node is a non-extending load.
2685 inline bool isNON_EXTLoad(const SDNode *N) {
2686 return isa<LoadSDNode>(N) &&
2687 cast<LoadSDNode>(N)->getExtensionType() == ISD::NON_EXTLOAD;
2688 }
2689
2690 /// Returns true if the specified node is a EXTLOAD.
2691 inline bool isEXTLoad(const SDNode *N) {
2692 return isa<LoadSDNode>(N) &&
2693 cast<LoadSDNode>(N)->getExtensionType() == ISD::EXTLOAD;
2694 }
2695
2696 /// Returns true if the specified node is a SEXTLOAD.
2697 inline bool isSEXTLoad(const SDNode *N) {
2698 return isa<LoadSDNode>(N) &&
2699 cast<LoadSDNode>(N)->getExtensionType() == ISD::SEXTLOAD;
2700 }
2701
2702 /// Returns true if the specified node is a ZEXTLOAD.
2703 inline bool isZEXTLoad(const SDNode *N) {
2704 return isa<LoadSDNode>(N) &&
2705 cast<LoadSDNode>(N)->getExtensionType() == ISD::ZEXTLOAD;
2706 }
2707
2708 /// Returns true if the specified node is an unindexed load.
2709 inline bool isUNINDEXEDLoad(const SDNode *N) {
2710 return isa<LoadSDNode>(N) &&
2711 cast<LoadSDNode>(N)->getAddressingMode() == ISD::UNINDEXED;
2712 }
2713
2714 /// Returns true if the specified node is a non-truncating
2715 /// and unindexed store.
2716 inline bool isNormalStore(const SDNode *N) {
2717 const StoreSDNode *St = dyn_cast<StoreSDNode>(N);
2718 return St && !St->isTruncatingStore() &&
2719 St->getAddressingMode() == ISD::UNINDEXED;
2720 }
2721
2722 /// Returns true if the specified node is an unindexed store.
2723 inline bool isUNINDEXEDStore(const SDNode *N) {
2724 return isa<StoreSDNode>(N) &&
2725 cast<StoreSDNode>(N)->getAddressingMode() == ISD::UNINDEXED;
2726 }
2727
2728 /// Attempt to match a unary predicate against a scalar/splat constant or
2729 /// every element of a constant BUILD_VECTOR.
2730 /// If AllowUndef is true, then UNDEF elements will pass nullptr to Match.
2731 bool matchUnaryPredicate(SDValue Op,
2732 std::function<bool(ConstantSDNode *)> Match,
2733 bool AllowUndefs = false);
2734
2735 /// Attempt to match a binary predicate against a pair of scalar/splat
2736 /// constants or every element of a pair of constant BUILD_VECTORs.
2737 /// If AllowUndef is true, then UNDEF elements will pass nullptr to Match.
2738 /// If AllowTypeMismatch is true then RetType + ArgTypes don't need to match.
2739 bool matchBinaryPredicate(
2740 SDValue LHS, SDValue RHS,
2741 std::function<bool(ConstantSDNode *, ConstantSDNode *)> Match,
2742 bool AllowUndefs = false, bool AllowTypeMismatch = false);
2743
2744 /// Returns true if the specified value is the overflow result from one
2745 /// of the overflow intrinsic nodes.
2746 inline bool isOverflowIntrOpRes(SDValue Op) {
2747 unsigned Opc = Op.getOpcode();
2748 return (Op.getResNo() == 1 &&
2749 (Opc == ISD::SADDO || Opc == ISD::UADDO || Opc == ISD::SSUBO ||
2750 Opc == ISD::USUBO || Opc == ISD::SMULO || Opc == ISD::UMULO));
2751 }
2752
2753} // end namespace ISD
2754
2755} // end namespace llvm
2756
2757#endif // LLVM_CODEGEN_SELECTIONDAGNODES_H