Bug Summary

File:llvm/lib/Transforms/Utils/CodeExtractor.cpp
Warning:line 957, column 33
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name CodeExtractor.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 -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/lib/Transforms/Utils -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/include -I /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/build-llvm/lib/Transforms/Utils -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2020-11-21-121427-42170-1 -x c++ /build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp
1//===- CodeExtractor.cpp - Pull code region into a new function -----------===//
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 implements the interface to tear out a code region, such as an
10// individual loop or a parallel section, into a new function, replacing it with
11// a call to the new function.
12//
13//===----------------------------------------------------------------------===//
14
15#include "llvm/Transforms/Utils/CodeExtractor.h"
16#include "llvm/ADT/ArrayRef.h"
17#include "llvm/ADT/DenseMap.h"
18#include "llvm/ADT/Optional.h"
19#include "llvm/ADT/STLExtras.h"
20#include "llvm/ADT/SetVector.h"
21#include "llvm/ADT/SmallPtrSet.h"
22#include "llvm/ADT/SmallVector.h"
23#include "llvm/Analysis/AssumptionCache.h"
24#include "llvm/Analysis/BlockFrequencyInfo.h"
25#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
26#include "llvm/Analysis/BranchProbabilityInfo.h"
27#include "llvm/Analysis/LoopInfo.h"
28#include "llvm/IR/Argument.h"
29#include "llvm/IR/Attributes.h"
30#include "llvm/IR/BasicBlock.h"
31#include "llvm/IR/CFG.h"
32#include "llvm/IR/Constant.h"
33#include "llvm/IR/Constants.h"
34#include "llvm/IR/DIBuilder.h"
35#include "llvm/IR/DataLayout.h"
36#include "llvm/IR/DebugInfoMetadata.h"
37#include "llvm/IR/DerivedTypes.h"
38#include "llvm/IR/Dominators.h"
39#include "llvm/IR/Function.h"
40#include "llvm/IR/GlobalValue.h"
41#include "llvm/IR/InstIterator.h"
42#include "llvm/IR/InstrTypes.h"
43#include "llvm/IR/Instruction.h"
44#include "llvm/IR/Instructions.h"
45#include "llvm/IR/IntrinsicInst.h"
46#include "llvm/IR/Intrinsics.h"
47#include "llvm/IR/LLVMContext.h"
48#include "llvm/IR/MDBuilder.h"
49#include "llvm/IR/Module.h"
50#include "llvm/IR/PatternMatch.h"
51#include "llvm/IR/Type.h"
52#include "llvm/IR/User.h"
53#include "llvm/IR/Value.h"
54#include "llvm/IR/Verifier.h"
55#include "llvm/Pass.h"
56#include "llvm/Support/BlockFrequency.h"
57#include "llvm/Support/BranchProbability.h"
58#include "llvm/Support/Casting.h"
59#include "llvm/Support/CommandLine.h"
60#include "llvm/Support/Debug.h"
61#include "llvm/Support/ErrorHandling.h"
62#include "llvm/Support/raw_ostream.h"
63#include "llvm/Transforms/Utils/BasicBlockUtils.h"
64#include "llvm/Transforms/Utils/Local.h"
65#include <cassert>
66#include <cstdint>
67#include <iterator>
68#include <map>
69#include <set>
70#include <utility>
71#include <vector>
72
73using namespace llvm;
74using namespace llvm::PatternMatch;
75using ProfileCount = Function::ProfileCount;
76
77#define DEBUG_TYPE"code-extractor" "code-extractor"
78
79// Provide a command-line option to aggregate function arguments into a struct
80// for functions produced by the code extractor. This is useful when converting
81// extracted functions to pthread-based code, as only one argument (void*) can
82// be passed in to pthread_create().
83static cl::opt<bool>
84AggregateArgsOpt("aggregate-extracted-args", cl::Hidden,
85 cl::desc("Aggregate arguments to code-extracted functions"));
86
87/// Test whether a block is valid for extraction.
88static bool isBlockValidForExtraction(const BasicBlock &BB,
89 const SetVector<BasicBlock *> &Result,
90 bool AllowVarArgs, bool AllowAlloca) {
91 // taking the address of a basic block moved to another function is illegal
92 if (BB.hasAddressTaken())
93 return false;
94
95 // don't hoist code that uses another basicblock address, as it's likely to
96 // lead to unexpected behavior, like cross-function jumps
97 SmallPtrSet<User const *, 16> Visited;
98 SmallVector<User const *, 16> ToVisit;
99
100 for (Instruction const &Inst : BB)
101 ToVisit.push_back(&Inst);
102
103 while (!ToVisit.empty()) {
104 User const *Curr = ToVisit.pop_back_val();
105 if (!Visited.insert(Curr).second)
106 continue;
107 if (isa<BlockAddress const>(Curr))
108 return false; // even a reference to self is likely to be not compatible
109
110 if (isa<Instruction>(Curr) && cast<Instruction>(Curr)->getParent() != &BB)
111 continue;
112
113 for (auto const &U : Curr->operands()) {
114 if (auto *UU = dyn_cast<User>(U))
115 ToVisit.push_back(UU);
116 }
117 }
118
119 // If explicitly requested, allow vastart and alloca. For invoke instructions
120 // verify that extraction is valid.
121 for (BasicBlock::const_iterator I = BB.begin(), E = BB.end(); I != E; ++I) {
122 if (isa<AllocaInst>(I)) {
123 if (!AllowAlloca)
124 return false;
125 continue;
126 }
127
128 if (const auto *II = dyn_cast<InvokeInst>(I)) {
129 // Unwind destination (either a landingpad, catchswitch, or cleanuppad)
130 // must be a part of the subgraph which is being extracted.
131 if (auto *UBB = II->getUnwindDest())
132 if (!Result.count(UBB))
133 return false;
134 continue;
135 }
136
137 // All catch handlers of a catchswitch instruction as well as the unwind
138 // destination must be in the subgraph.
139 if (const auto *CSI = dyn_cast<CatchSwitchInst>(I)) {
140 if (auto *UBB = CSI->getUnwindDest())
141 if (!Result.count(UBB))
142 return false;
143 for (auto *HBB : CSI->handlers())
144 if (!Result.count(const_cast<BasicBlock*>(HBB)))
145 return false;
146 continue;
147 }
148
149 // Make sure that entire catch handler is within subgraph. It is sufficient
150 // to check that catch return's block is in the list.
151 if (const auto *CPI = dyn_cast<CatchPadInst>(I)) {
152 for (const auto *U : CPI->users())
153 if (const auto *CRI = dyn_cast<CatchReturnInst>(U))
154 if (!Result.count(const_cast<BasicBlock*>(CRI->getParent())))
155 return false;
156 continue;
157 }
158
159 // And do similar checks for cleanup handler - the entire handler must be
160 // in subgraph which is going to be extracted. For cleanup return should
161 // additionally check that the unwind destination is also in the subgraph.
162 if (const auto *CPI = dyn_cast<CleanupPadInst>(I)) {
163 for (const auto *U : CPI->users())
164 if (const auto *CRI = dyn_cast<CleanupReturnInst>(U))
165 if (!Result.count(const_cast<BasicBlock*>(CRI->getParent())))
166 return false;
167 continue;
168 }
169 if (const auto *CRI = dyn_cast<CleanupReturnInst>(I)) {
170 if (auto *UBB = CRI->getUnwindDest())
171 if (!Result.count(UBB))
172 return false;
173 continue;
174 }
175
176 if (const CallInst *CI = dyn_cast<CallInst>(I)) {
177 if (const Function *F = CI->getCalledFunction()) {
178 auto IID = F->getIntrinsicID();
179 if (IID == Intrinsic::vastart) {
180 if (AllowVarArgs)
181 continue;
182 else
183 return false;
184 }
185
186 // Currently, we miscompile outlined copies of eh_typid_for. There are
187 // proposals for fixing this in llvm.org/PR39545.
188 if (IID == Intrinsic::eh_typeid_for)
189 return false;
190 }
191 }
192 }
193
194 return true;
195}
196
197/// Build a set of blocks to extract if the input blocks are viable.
198static SetVector<BasicBlock *>
199buildExtractionBlockSet(ArrayRef<BasicBlock *> BBs, DominatorTree *DT,
200 bool AllowVarArgs, bool AllowAlloca) {
201 assert(!BBs.empty() && "The set of blocks to extract must be non-empty")((!BBs.empty() && "The set of blocks to extract must be non-empty"
) ? static_cast<void> (0) : __assert_fail ("!BBs.empty() && \"The set of blocks to extract must be non-empty\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 201, __PRETTY_FUNCTION__))
;
202 SetVector<BasicBlock *> Result;
203
204 // Loop over the blocks, adding them to our set-vector, and aborting with an
205 // empty set if we encounter invalid blocks.
206 for (BasicBlock *BB : BBs) {
207 // If this block is dead, don't process it.
208 if (DT && !DT->isReachableFromEntry(BB))
209 continue;
210
211 if (!Result.insert(BB))
212 llvm_unreachable("Repeated basic blocks in extraction input")::llvm::llvm_unreachable_internal("Repeated basic blocks in extraction input"
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 212)
;
213 }
214
215 LLVM_DEBUG(dbgs() << "Region front block: " << Result.front()->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Region front block: " <<
Result.front()->getName() << '\n'; } } while (false
)
216 << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Region front block: " <<
Result.front()->getName() << '\n'; } } while (false
)
;
217
218 for (auto *BB : Result) {
219 if (!isBlockValidForExtraction(*BB, Result, AllowVarArgs, AllowAlloca))
220 return {};
221
222 // Make sure that the first block is not a landing pad.
223 if (BB == Result.front()) {
224 if (BB->isEHPad()) {
225 LLVM_DEBUG(dbgs() << "The first block cannot be an unwind block\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "The first block cannot be an unwind block\n"
; } } while (false)
;
226 return {};
227 }
228 continue;
229 }
230
231 // All blocks other than the first must not have predecessors outside of
232 // the subgraph which is being extracted.
233 for (auto *PBB : predecessors(BB))
234 if (!Result.count(PBB)) {
235 LLVM_DEBUG(dbgs() << "No blocks in this region may have entries from "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "No blocks in this region may have entries from "
"outside the region except for the first block!\n" << "Problematic source BB: "
<< BB->getName() << "\n" << "Problematic destination BB: "
<< PBB->getName() << "\n"; } } while (false)
236 "outside the region except for the first block!\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "No blocks in this region may have entries from "
"outside the region except for the first block!\n" << "Problematic source BB: "
<< BB->getName() << "\n" << "Problematic destination BB: "
<< PBB->getName() << "\n"; } } while (false)
237 << "Problematic source BB: " << BB->getName() << "\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "No blocks in this region may have entries from "
"outside the region except for the first block!\n" << "Problematic source BB: "
<< BB->getName() << "\n" << "Problematic destination BB: "
<< PBB->getName() << "\n"; } } while (false)
238 << "Problematic destination BB: " << PBB->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "No blocks in this region may have entries from "
"outside the region except for the first block!\n" << "Problematic source BB: "
<< BB->getName() << "\n" << "Problematic destination BB: "
<< PBB->getName() << "\n"; } } while (false)
239 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "No blocks in this region may have entries from "
"outside the region except for the first block!\n" << "Problematic source BB: "
<< BB->getName() << "\n" << "Problematic destination BB: "
<< PBB->getName() << "\n"; } } while (false)
;
240 return {};
241 }
242 }
243
244 return Result;
245}
246
247CodeExtractor::CodeExtractor(ArrayRef<BasicBlock *> BBs, DominatorTree *DT,
248 bool AggregateArgs, BlockFrequencyInfo *BFI,
249 BranchProbabilityInfo *BPI, AssumptionCache *AC,
250 bool AllowVarArgs, bool AllowAlloca,
251 std::string Suffix)
252 : DT(DT), AggregateArgs(AggregateArgs || AggregateArgsOpt), BFI(BFI),
253 BPI(BPI), AC(AC), AllowVarArgs(AllowVarArgs),
254 Blocks(buildExtractionBlockSet(BBs, DT, AllowVarArgs, AllowAlloca)),
255 Suffix(Suffix) {}
256
257CodeExtractor::CodeExtractor(DominatorTree &DT, Loop &L, bool AggregateArgs,
258 BlockFrequencyInfo *BFI,
259 BranchProbabilityInfo *BPI, AssumptionCache *AC,
260 std::string Suffix)
261 : DT(&DT), AggregateArgs(AggregateArgs || AggregateArgsOpt), BFI(BFI),
262 BPI(BPI), AC(AC), AllowVarArgs(false),
263 Blocks(buildExtractionBlockSet(L.getBlocks(), &DT,
264 /* AllowVarArgs */ false,
265 /* AllowAlloca */ false)),
266 Suffix(Suffix) {}
267
268/// definedInRegion - Return true if the specified value is defined in the
269/// extracted region.
270static bool definedInRegion(const SetVector<BasicBlock *> &Blocks, Value *V) {
271 if (Instruction *I = dyn_cast<Instruction>(V))
272 if (Blocks.count(I->getParent()))
273 return true;
274 return false;
275}
276
277/// definedInCaller - Return true if the specified value is defined in the
278/// function being code extracted, but not in the region being extracted.
279/// These values must be passed in as live-ins to the function.
280static bool definedInCaller(const SetVector<BasicBlock *> &Blocks, Value *V) {
281 if (isa<Argument>(V)) return true;
282 if (Instruction *I = dyn_cast<Instruction>(V))
283 if (!Blocks.count(I->getParent()))
284 return true;
285 return false;
286}
287
288static BasicBlock *getCommonExitBlock(const SetVector<BasicBlock *> &Blocks) {
289 BasicBlock *CommonExitBlock = nullptr;
290 auto hasNonCommonExitSucc = [&](BasicBlock *Block) {
291 for (auto *Succ : successors(Block)) {
292 // Internal edges, ok.
293 if (Blocks.count(Succ))
294 continue;
295 if (!CommonExitBlock) {
296 CommonExitBlock = Succ;
297 continue;
298 }
299 if (CommonExitBlock != Succ)
300 return true;
301 }
302 return false;
303 };
304
305 if (any_of(Blocks, hasNonCommonExitSucc))
306 return nullptr;
307
308 return CommonExitBlock;
309}
310
311CodeExtractorAnalysisCache::CodeExtractorAnalysisCache(Function &F) {
312 for (BasicBlock &BB : F) {
313 for (Instruction &II : BB.instructionsWithoutDebug())
314 if (auto *AI = dyn_cast<AllocaInst>(&II))
315 Allocas.push_back(AI);
316
317 findSideEffectInfoForBlock(BB);
318 }
319}
320
321void CodeExtractorAnalysisCache::findSideEffectInfoForBlock(BasicBlock &BB) {
322 for (Instruction &II : BB.instructionsWithoutDebug()) {
323 unsigned Opcode = II.getOpcode();
324 Value *MemAddr = nullptr;
325 switch (Opcode) {
326 case Instruction::Store:
327 case Instruction::Load: {
328 if (Opcode == Instruction::Store) {
329 StoreInst *SI = cast<StoreInst>(&II);
330 MemAddr = SI->getPointerOperand();
331 } else {
332 LoadInst *LI = cast<LoadInst>(&II);
333 MemAddr = LI->getPointerOperand();
334 }
335 // Global variable can not be aliased with locals.
336 if (dyn_cast<Constant>(MemAddr))
337 break;
338 Value *Base = MemAddr->stripInBoundsConstantOffsets();
339 if (!isa<AllocaInst>(Base)) {
340 SideEffectingBlocks.insert(&BB);
341 return;
342 }
343 BaseMemAddrs[&BB].insert(Base);
344 break;
345 }
346 default: {
347 IntrinsicInst *IntrInst = dyn_cast<IntrinsicInst>(&II);
348 if (IntrInst) {
349 if (IntrInst->isLifetimeStartOrEnd())
350 break;
351 SideEffectingBlocks.insert(&BB);
352 return;
353 }
354 // Treat all the other cases conservatively if it has side effects.
355 if (II.mayHaveSideEffects()) {
356 SideEffectingBlocks.insert(&BB);
357 return;
358 }
359 }
360 }
361 }
362}
363
364bool CodeExtractorAnalysisCache::doesBlockContainClobberOfAddr(
365 BasicBlock &BB, AllocaInst *Addr) const {
366 if (SideEffectingBlocks.count(&BB))
367 return true;
368 auto It = BaseMemAddrs.find(&BB);
369 if (It != BaseMemAddrs.end())
370 return It->second.count(Addr);
371 return false;
372}
373
374bool CodeExtractor::isLegalToShrinkwrapLifetimeMarkers(
375 const CodeExtractorAnalysisCache &CEAC, Instruction *Addr) const {
376 AllocaInst *AI = cast<AllocaInst>(Addr->stripInBoundsConstantOffsets());
377 Function *Func = (*Blocks.begin())->getParent();
378 for (BasicBlock &BB : *Func) {
379 if (Blocks.count(&BB))
380 continue;
381 if (CEAC.doesBlockContainClobberOfAddr(BB, AI))
382 return false;
383 }
384 return true;
385}
386
387BasicBlock *
388CodeExtractor::findOrCreateBlockForHoisting(BasicBlock *CommonExitBlock) {
389 BasicBlock *SinglePredFromOutlineRegion = nullptr;
390 assert(!Blocks.count(CommonExitBlock) &&((!Blocks.count(CommonExitBlock) && "Expect a block outside the region!"
) ? static_cast<void> (0) : __assert_fail ("!Blocks.count(CommonExitBlock) && \"Expect a block outside the region!\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 391, __PRETTY_FUNCTION__))
391 "Expect a block outside the region!")((!Blocks.count(CommonExitBlock) && "Expect a block outside the region!"
) ? static_cast<void> (0) : __assert_fail ("!Blocks.count(CommonExitBlock) && \"Expect a block outside the region!\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 391, __PRETTY_FUNCTION__))
;
392 for (auto *Pred : predecessors(CommonExitBlock)) {
393 if (!Blocks.count(Pred))
394 continue;
395 if (!SinglePredFromOutlineRegion) {
396 SinglePredFromOutlineRegion = Pred;
397 } else if (SinglePredFromOutlineRegion != Pred) {
398 SinglePredFromOutlineRegion = nullptr;
399 break;
400 }
401 }
402
403 if (SinglePredFromOutlineRegion)
404 return SinglePredFromOutlineRegion;
405
406#ifndef NDEBUG
407 auto getFirstPHI = [](BasicBlock *BB) {
408 BasicBlock::iterator I = BB->begin();
409 PHINode *FirstPhi = nullptr;
410 while (I != BB->end()) {
411 PHINode *Phi = dyn_cast<PHINode>(I);
412 if (!Phi)
413 break;
414 if (!FirstPhi) {
415 FirstPhi = Phi;
416 break;
417 }
418 }
419 return FirstPhi;
420 };
421 // If there are any phi nodes, the single pred either exists or has already
422 // be created before code extraction.
423 assert(!getFirstPHI(CommonExitBlock) && "Phi not expected")((!getFirstPHI(CommonExitBlock) && "Phi not expected"
) ? static_cast<void> (0) : __assert_fail ("!getFirstPHI(CommonExitBlock) && \"Phi not expected\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 423, __PRETTY_FUNCTION__))
;
424#endif
425
426 BasicBlock *NewExitBlock = CommonExitBlock->splitBasicBlock(
427 CommonExitBlock->getFirstNonPHI()->getIterator());
428
429 for (auto PI = pred_begin(CommonExitBlock), PE = pred_end(CommonExitBlock);
430 PI != PE;) {
431 BasicBlock *Pred = *PI++;
432 if (Blocks.count(Pred))
433 continue;
434 Pred->getTerminator()->replaceUsesOfWith(CommonExitBlock, NewExitBlock);
435 }
436 // Now add the old exit block to the outline region.
437 Blocks.insert(CommonExitBlock);
438 return CommonExitBlock;
439}
440
441// Find the pair of life time markers for address 'Addr' that are either
442// defined inside the outline region or can legally be shrinkwrapped into the
443// outline region. If there are not other untracked uses of the address, return
444// the pair of markers if found; otherwise return a pair of nullptr.
445CodeExtractor::LifetimeMarkerInfo
446CodeExtractor::getLifetimeMarkers(const CodeExtractorAnalysisCache &CEAC,
447 Instruction *Addr,
448 BasicBlock *ExitBlock) const {
449 LifetimeMarkerInfo Info;
450
451 for (User *U : Addr->users()) {
452 IntrinsicInst *IntrInst = dyn_cast<IntrinsicInst>(U);
453 if (IntrInst) {
454 // We don't model addresses with multiple start/end markers, but the
455 // markers do not need to be in the region.
456 if (IntrInst->getIntrinsicID() == Intrinsic::lifetime_start) {
457 if (Info.LifeStart)
458 return {};
459 Info.LifeStart = IntrInst;
460 continue;
461 }
462 if (IntrInst->getIntrinsicID() == Intrinsic::lifetime_end) {
463 if (Info.LifeEnd)
464 return {};
465 Info.LifeEnd = IntrInst;
466 continue;
467 }
468 // At this point, permit debug uses outside of the region.
469 // This is fixed in a later call to fixupDebugInfoPostExtraction().
470 if (isa<DbgInfoIntrinsic>(IntrInst))
471 continue;
472 }
473 // Find untracked uses of the address, bail.
474 if (!definedInRegion(Blocks, U))
475 return {};
476 }
477
478 if (!Info.LifeStart || !Info.LifeEnd)
479 return {};
480
481 Info.SinkLifeStart = !definedInRegion(Blocks, Info.LifeStart);
482 Info.HoistLifeEnd = !definedInRegion(Blocks, Info.LifeEnd);
483 // Do legality check.
484 if ((Info.SinkLifeStart || Info.HoistLifeEnd) &&
485 !isLegalToShrinkwrapLifetimeMarkers(CEAC, Addr))
486 return {};
487
488 // Check to see if we have a place to do hoisting, if not, bail.
489 if (Info.HoistLifeEnd && !ExitBlock)
490 return {};
491
492 return Info;
493}
494
495void CodeExtractor::findAllocas(const CodeExtractorAnalysisCache &CEAC,
496 ValueSet &SinkCands, ValueSet &HoistCands,
497 BasicBlock *&ExitBlock) const {
498 Function *Func = (*Blocks.begin())->getParent();
499 ExitBlock = getCommonExitBlock(Blocks);
500
501 auto moveOrIgnoreLifetimeMarkers =
502 [&](const LifetimeMarkerInfo &LMI) -> bool {
503 if (!LMI.LifeStart)
504 return false;
505 if (LMI.SinkLifeStart) {
506 LLVM_DEBUG(dbgs() << "Sinking lifetime.start: " << *LMI.LifeStartdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Sinking lifetime.start: "
<< *LMI.LifeStart << "\n"; } } while (false)
507 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Sinking lifetime.start: "
<< *LMI.LifeStart << "\n"; } } while (false)
;
508 SinkCands.insert(LMI.LifeStart);
509 }
510 if (LMI.HoistLifeEnd) {
511 LLVM_DEBUG(dbgs() << "Hoisting lifetime.end: " << *LMI.LifeEnd << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Hoisting lifetime.end: "
<< *LMI.LifeEnd << "\n"; } } while (false)
;
512 HoistCands.insert(LMI.LifeEnd);
513 }
514 return true;
515 };
516
517 // Look up allocas in the original function in CodeExtractorAnalysisCache, as
518 // this is much faster than walking all the instructions.
519 for (AllocaInst *AI : CEAC.getAllocas()) {
520 BasicBlock *BB = AI->getParent();
521 if (Blocks.count(BB))
522 continue;
523
524 // As a prior call to extractCodeRegion() may have shrinkwrapped the alloca,
525 // check whether it is actually still in the original function.
526 Function *AIFunc = BB->getParent();
527 if (AIFunc != Func)
528 continue;
529
530 LifetimeMarkerInfo MarkerInfo = getLifetimeMarkers(CEAC, AI, ExitBlock);
531 bool Moved = moveOrIgnoreLifetimeMarkers(MarkerInfo);
532 if (Moved) {
533 LLVM_DEBUG(dbgs() << "Sinking alloca: " << *AI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Sinking alloca: " <<
*AI << "\n"; } } while (false)
;
534 SinkCands.insert(AI);
535 continue;
536 }
537
538 // Follow any bitcasts.
539 SmallVector<Instruction *, 2> Bitcasts;
540 SmallVector<LifetimeMarkerInfo, 2> BitcastLifetimeInfo;
541 for (User *U : AI->users()) {
542 if (U->stripInBoundsConstantOffsets() == AI) {
543 Instruction *Bitcast = cast<Instruction>(U);
544 LifetimeMarkerInfo LMI = getLifetimeMarkers(CEAC, Bitcast, ExitBlock);
545 if (LMI.LifeStart) {
546 Bitcasts.push_back(Bitcast);
547 BitcastLifetimeInfo.push_back(LMI);
548 continue;
549 }
550 }
551
552 // Found unknown use of AI.
553 if (!definedInRegion(Blocks, U)) {
554 Bitcasts.clear();
555 break;
556 }
557 }
558
559 // Either no bitcasts reference the alloca or there are unknown uses.
560 if (Bitcasts.empty())
561 continue;
562
563 LLVM_DEBUG(dbgs() << "Sinking alloca (via bitcast): " << *AI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Sinking alloca (via bitcast): "
<< *AI << "\n"; } } while (false)
;
564 SinkCands.insert(AI);
565 for (unsigned I = 0, E = Bitcasts.size(); I != E; ++I) {
566 Instruction *BitcastAddr = Bitcasts[I];
567 const LifetimeMarkerInfo &LMI = BitcastLifetimeInfo[I];
568 assert(LMI.LifeStart &&((LMI.LifeStart && "Unsafe to sink bitcast without lifetime markers"
) ? static_cast<void> (0) : __assert_fail ("LMI.LifeStart && \"Unsafe to sink bitcast without lifetime markers\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 569, __PRETTY_FUNCTION__))
569 "Unsafe to sink bitcast without lifetime markers")((LMI.LifeStart && "Unsafe to sink bitcast without lifetime markers"
) ? static_cast<void> (0) : __assert_fail ("LMI.LifeStart && \"Unsafe to sink bitcast without lifetime markers\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 569, __PRETTY_FUNCTION__))
;
570 moveOrIgnoreLifetimeMarkers(LMI);
571 if (!definedInRegion(Blocks, BitcastAddr)) {
572 LLVM_DEBUG(dbgs() << "Sinking bitcast-of-alloca: " << *BitcastAddrdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Sinking bitcast-of-alloca: "
<< *BitcastAddr << "\n"; } } while (false)
573 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "Sinking bitcast-of-alloca: "
<< *BitcastAddr << "\n"; } } while (false)
;
574 SinkCands.insert(BitcastAddr);
575 }
576 }
577 }
578}
579
580bool CodeExtractor::isEligible() const {
581 if (Blocks.empty())
582 return false;
583 BasicBlock *Header = *Blocks.begin();
584 Function *F = Header->getParent();
585
586 // For functions with varargs, check that varargs handling is only done in the
587 // outlined function, i.e vastart and vaend are only used in outlined blocks.
588 if (AllowVarArgs && F->getFunctionType()->isVarArg()) {
589 auto containsVarArgIntrinsic = [](const Instruction &I) {
590 if (const CallInst *CI = dyn_cast<CallInst>(&I))
591 if (const Function *Callee = CI->getCalledFunction())
592 return Callee->getIntrinsicID() == Intrinsic::vastart ||
593 Callee->getIntrinsicID() == Intrinsic::vaend;
594 return false;
595 };
596
597 for (auto &BB : *F) {
598 if (Blocks.count(&BB))
599 continue;
600 if (llvm::any_of(BB, containsVarArgIntrinsic))
601 return false;
602 }
603 }
604 return true;
605}
606
607void CodeExtractor::findInputsOutputs(ValueSet &Inputs, ValueSet &Outputs,
608 const ValueSet &SinkCands) const {
609 for (BasicBlock *BB : Blocks) {
610 // If a used value is defined outside the region, it's an input. If an
611 // instruction is used outside the region, it's an output.
612 for (Instruction &II : *BB) {
613 for (auto &OI : II.operands()) {
614 Value *V = OI;
615 if (!SinkCands.count(V) && definedInCaller(Blocks, V))
616 Inputs.insert(V);
617 }
618
619 for (User *U : II.users())
620 if (!definedInRegion(Blocks, U)) {
621 Outputs.insert(&II);
622 break;
623 }
624 }
625 }
626}
627
628/// severSplitPHINodesOfEntry - If a PHI node has multiple inputs from outside
629/// of the region, we need to split the entry block of the region so that the
630/// PHI node is easier to deal with.
631void CodeExtractor::severSplitPHINodesOfEntry(BasicBlock *&Header) {
632 unsigned NumPredsFromRegion = 0;
633 unsigned NumPredsOutsideRegion = 0;
634
635 if (Header != &Header->getParent()->getEntryBlock()) {
636 PHINode *PN = dyn_cast<PHINode>(Header->begin());
637 if (!PN) return; // No PHI nodes.
638
639 // If the header node contains any PHI nodes, check to see if there is more
640 // than one entry from outside the region. If so, we need to sever the
641 // header block into two.
642 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
643 if (Blocks.count(PN->getIncomingBlock(i)))
644 ++NumPredsFromRegion;
645 else
646 ++NumPredsOutsideRegion;
647
648 // If there is one (or fewer) predecessor from outside the region, we don't
649 // need to do anything special.
650 if (NumPredsOutsideRegion <= 1) return;
651 }
652
653 // Otherwise, we need to split the header block into two pieces: one
654 // containing PHI nodes merging values from outside of the region, and a
655 // second that contains all of the code for the block and merges back any
656 // incoming values from inside of the region.
657 BasicBlock *NewBB = SplitBlock(Header, Header->getFirstNonPHI(), DT);
658
659 // We only want to code extract the second block now, and it becomes the new
660 // header of the region.
661 BasicBlock *OldPred = Header;
662 Blocks.remove(OldPred);
663 Blocks.insert(NewBB);
664 Header = NewBB;
665
666 // Okay, now we need to adjust the PHI nodes and any branches from within the
667 // region to go to the new header block instead of the old header block.
668 if (NumPredsFromRegion) {
669 PHINode *PN = cast<PHINode>(OldPred->begin());
670 // Loop over all of the predecessors of OldPred that are in the region,
671 // changing them to branch to NewBB instead.
672 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
673 if (Blocks.count(PN->getIncomingBlock(i))) {
674 Instruction *TI = PN->getIncomingBlock(i)->getTerminator();
675 TI->replaceUsesOfWith(OldPred, NewBB);
676 }
677
678 // Okay, everything within the region is now branching to the right block, we
679 // just have to update the PHI nodes now, inserting PHI nodes into NewBB.
680 BasicBlock::iterator AfterPHIs;
681 for (AfterPHIs = OldPred->begin(); isa<PHINode>(AfterPHIs); ++AfterPHIs) {
682 PHINode *PN = cast<PHINode>(AfterPHIs);
683 // Create a new PHI node in the new region, which has an incoming value
684 // from OldPred of PN.
685 PHINode *NewPN = PHINode::Create(PN->getType(), 1 + NumPredsFromRegion,
686 PN->getName() + ".ce", &NewBB->front());
687 PN->replaceAllUsesWith(NewPN);
688 NewPN->addIncoming(PN, OldPred);
689
690 // Loop over all of the incoming value in PN, moving them to NewPN if they
691 // are from the extracted region.
692 for (unsigned i = 0; i != PN->getNumIncomingValues(); ++i) {
693 if (Blocks.count(PN->getIncomingBlock(i))) {
694 NewPN->addIncoming(PN->getIncomingValue(i), PN->getIncomingBlock(i));
695 PN->removeIncomingValue(i);
696 --i;
697 }
698 }
699 }
700 }
701}
702
703/// severSplitPHINodesOfExits - if PHI nodes in exit blocks have inputs from
704/// outlined region, we split these PHIs on two: one with inputs from region
705/// and other with remaining incoming blocks; then first PHIs are placed in
706/// outlined region.
707void CodeExtractor::severSplitPHINodesOfExits(
708 const SmallPtrSetImpl<BasicBlock *> &Exits) {
709 for (BasicBlock *ExitBB : Exits) {
710 BasicBlock *NewBB = nullptr;
711
712 for (PHINode &PN : ExitBB->phis()) {
713 // Find all incoming values from the outlining region.
714 SmallVector<unsigned, 2> IncomingVals;
715 for (unsigned i = 0; i < PN.getNumIncomingValues(); ++i)
716 if (Blocks.count(PN.getIncomingBlock(i)))
717 IncomingVals.push_back(i);
718
719 // Do not process PHI if there is one (or fewer) predecessor from region.
720 // If PHI has exactly one predecessor from region, only this one incoming
721 // will be replaced on codeRepl block, so it should be safe to skip PHI.
722 if (IncomingVals.size() <= 1)
723 continue;
724
725 // Create block for new PHIs and add it to the list of outlined if it
726 // wasn't done before.
727 if (!NewBB) {
728 NewBB = BasicBlock::Create(ExitBB->getContext(),
729 ExitBB->getName() + ".split",
730 ExitBB->getParent(), ExitBB);
731 SmallVector<BasicBlock *, 4> Preds(pred_begin(ExitBB),
732 pred_end(ExitBB));
733 for (BasicBlock *PredBB : Preds)
734 if (Blocks.count(PredBB))
735 PredBB->getTerminator()->replaceUsesOfWith(ExitBB, NewBB);
736 BranchInst::Create(ExitBB, NewBB);
737 Blocks.insert(NewBB);
738 }
739
740 // Split this PHI.
741 PHINode *NewPN =
742 PHINode::Create(PN.getType(), IncomingVals.size(),
743 PN.getName() + ".ce", NewBB->getFirstNonPHI());
744 for (unsigned i : IncomingVals)
745 NewPN->addIncoming(PN.getIncomingValue(i), PN.getIncomingBlock(i));
746 for (unsigned i : reverse(IncomingVals))
747 PN.removeIncomingValue(i, false);
748 PN.addIncoming(NewPN, NewBB);
749 }
750 }
751}
752
753void CodeExtractor::splitReturnBlocks() {
754 for (BasicBlock *Block : Blocks)
755 if (ReturnInst *RI = dyn_cast<ReturnInst>(Block->getTerminator())) {
756 BasicBlock *New =
757 Block->splitBasicBlock(RI->getIterator(), Block->getName() + ".ret");
758 if (DT) {
759 // Old dominates New. New node dominates all other nodes dominated
760 // by Old.
761 DomTreeNode *OldNode = DT->getNode(Block);
762 SmallVector<DomTreeNode *, 8> Children(OldNode->begin(),
763 OldNode->end());
764
765 DomTreeNode *NewNode = DT->addNewBlock(New, Block);
766
767 for (DomTreeNode *I : Children)
768 DT->changeImmediateDominator(I, NewNode);
769 }
770 }
771}
772
773/// constructFunction - make a function based on inputs and outputs, as follows:
774/// f(in0, ..., inN, out0, ..., outN)
775Function *CodeExtractor::constructFunction(const ValueSet &inputs,
776 const ValueSet &outputs,
777 BasicBlock *header,
778 BasicBlock *newRootNode,
779 BasicBlock *newHeader,
780 Function *oldFunction,
781 Module *M) {
782 LLVM_DEBUG(dbgs() << "inputs: " << inputs.size() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "inputs: " << inputs
.size() << "\n"; } } while (false)
;
1
Assuming 'DebugFlag' is false
2
Loop condition is false. Exiting loop
783 LLVM_DEBUG(dbgs() << "outputs: " << outputs.size() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "outputs: " << outputs
.size() << "\n"; } } while (false)
;
3
Loop condition is false. Exiting loop
784
785 // This function returns unsigned, outputs will go back by reference.
786 switch (NumExitBlocks) {
4
Control jumps to the 'default' case at line 790
787 case 0:
788 case 1: RetTy = Type::getVoidTy(header->getContext()); break;
789 case 2: RetTy = Type::getInt1Ty(header->getContext()); break;
790 default: RetTy = Type::getInt16Ty(header->getContext()); break;
5
Execution continues on line 793
791 }
792
793 std::vector<Type *> paramTy;
794
795 // Add the types of the input values to the function's argument list
796 for (Value *value : inputs) {
797 LLVM_DEBUG(dbgs() << "value used in func: " << *value << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "value used in func: " <<
*value << "\n"; } } while (false)
;
798 paramTy.push_back(value->getType());
799 }
800
801 // Add the types of the output values to the function's argument list.
802 for (Value *output : outputs) {
803 LLVM_DEBUG(dbgs() << "instr used in func: " << *output << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { dbgs() << "instr used in func: " <<
*output << "\n"; } } while (false)
;
804 if (AggregateArgs)
805 paramTy.push_back(output->getType());
806 else
807 paramTy.push_back(PointerType::getUnqual(output->getType()));
808 }
809
810 LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { { dbgs() << "Function type: " <<
*RetTy << " f("; for (Type *i : paramTy) dbgs() <<
*i << ", "; dbgs() << ")\n"; }; } } while (false
)
6
Assuming 'DebugFlag' is false
7
Loop condition is false. Exiting loop
811 dbgs() << "Function type: " << *RetTy << " f(";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { { dbgs() << "Function type: " <<
*RetTy << " f("; for (Type *i : paramTy) dbgs() <<
*i << ", "; dbgs() << ")\n"; }; } } while (false
)
812 for (Type *i : paramTy)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { { dbgs() << "Function type: " <<
*RetTy << " f("; for (Type *i : paramTy) dbgs() <<
*i << ", "; dbgs() << ")\n"; }; } } while (false
)
813 dbgs() << *i << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { { dbgs() << "Function type: " <<
*RetTy << " f("; for (Type *i : paramTy) dbgs() <<
*i << ", "; dbgs() << ")\n"; }; } } while (false
)
814 dbgs() << ")\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { { dbgs() << "Function type: " <<
*RetTy << " f("; for (Type *i : paramTy) dbgs() <<
*i << ", "; dbgs() << ")\n"; }; } } while (false
)
815 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { { dbgs() << "Function type: " <<
*RetTy << " f("; for (Type *i : paramTy) dbgs() <<
*i << ", "; dbgs() << ")\n"; }; } } while (false
)
;
816
817 StructType *StructTy = nullptr;
8
'StructTy' initialized to a null pointer value
818 if (AggregateArgs && (inputs.size() + outputs.size() > 0)) {
9
Assuming field 'AggregateArgs' is true
10
Assuming the condition is false
11
Taking false branch
819 StructTy = StructType::get(M->getContext(), paramTy);
820 paramTy.clear();
821 paramTy.push_back(PointerType::getUnqual(StructTy));
822 }
823 FunctionType *funcType =
824 FunctionType::get(RetTy, paramTy,
825 AllowVarArgs && oldFunction->isVarArg());
12
Assuming field 'AllowVarArgs' is false
826
827 std::string SuffixToUse =
828 Suffix.empty()
13
Assuming the condition is false
14
'?' condition is false
829 ? (header->getName().empty() ? "extracted" : header->getName().str())
830 : Suffix;
831 // Create the new function
832 Function *newFunction = Function::Create(
833 funcType, GlobalValue::InternalLinkage, oldFunction->getAddressSpace(),
834 oldFunction->getName() + "." + SuffixToUse, M);
835 // If the old function is no-throw, so is the new one.
836 if (oldFunction->doesNotThrow())
15
Assuming the condition is false
16
Taking false branch
837 newFunction->setDoesNotThrow();
838
839 // Inherit the uwtable attribute if we need to.
840 if (oldFunction->hasUWTable())
17
Assuming the condition is false
18
Taking false branch
841 newFunction->setHasUWTable();
842
843 // Inherit all of the target dependent attributes and white-listed
844 // target independent attributes.
845 // (e.g. If the extracted region contains a call to an x86.sse
846 // instruction we need to make sure that the extracted region has the
847 // "target-features" attribute allowing it to be lowered.
848 // FIXME: This should be changed to check to see if a specific
849 // attribute can not be inherited.
850 for (const auto &Attr : oldFunction->getAttributes().getFnAttributes()) {
19
Assuming '__begin1' is equal to '__end1'
851 if (Attr.isStringAttribute()) {
852 if (Attr.getKindAsString() == "thunk")
853 continue;
854 } else
855 switch (Attr.getKindAsEnum()) {
856 // Those attributes cannot be propagated safely. Explicitly list them
857 // here so we get a warning if new attributes are added. This list also
858 // includes non-function attributes.
859 case Attribute::Alignment:
860 case Attribute::AllocSize:
861 case Attribute::ArgMemOnly:
862 case Attribute::Builtin:
863 case Attribute::ByVal:
864 case Attribute::Convergent:
865 case Attribute::Dereferenceable:
866 case Attribute::DereferenceableOrNull:
867 case Attribute::InAlloca:
868 case Attribute::InReg:
869 case Attribute::InaccessibleMemOnly:
870 case Attribute::InaccessibleMemOrArgMemOnly:
871 case Attribute::JumpTable:
872 case Attribute::Naked:
873 case Attribute::Nest:
874 case Attribute::NoAlias:
875 case Attribute::NoBuiltin:
876 case Attribute::NoCapture:
877 case Attribute::NoMerge:
878 case Attribute::NoReturn:
879 case Attribute::NoSync:
880 case Attribute::NoUndef:
881 case Attribute::None:
882 case Attribute::NonNull:
883 case Attribute::Preallocated:
884 case Attribute::ReadNone:
885 case Attribute::ReadOnly:
886 case Attribute::Returned:
887 case Attribute::ReturnsTwice:
888 case Attribute::SExt:
889 case Attribute::Speculatable:
890 case Attribute::StackAlignment:
891 case Attribute::StructRet:
892 case Attribute::SwiftError:
893 case Attribute::SwiftSelf:
894 case Attribute::WillReturn:
895 case Attribute::WriteOnly:
896 case Attribute::ZExt:
897 case Attribute::ImmArg:
898 case Attribute::ByRef:
899 case Attribute::EndAttrKinds:
900 case Attribute::EmptyKey:
901 case Attribute::TombstoneKey:
902 continue;
903 // Those attributes should be safe to propagate to the extracted function.
904 case Attribute::AlwaysInline:
905 case Attribute::Cold:
906 case Attribute::NoRecurse:
907 case Attribute::InlineHint:
908 case Attribute::MinSize:
909 case Attribute::NoDuplicate:
910 case Attribute::NoFree:
911 case Attribute::NoImplicitFloat:
912 case Attribute::NoInline:
913 case Attribute::NonLazyBind:
914 case Attribute::NoRedZone:
915 case Attribute::NoUnwind:
916 case Attribute::NullPointerIsValid:
917 case Attribute::OptForFuzzing:
918 case Attribute::OptimizeNone:
919 case Attribute::OptimizeForSize:
920 case Attribute::SafeStack:
921 case Attribute::ShadowCallStack:
922 case Attribute::SanitizeAddress:
923 case Attribute::SanitizeMemory:
924 case Attribute::SanitizeThread:
925 case Attribute::SanitizeHWAddress:
926 case Attribute::SanitizeMemTag:
927 case Attribute::SpeculativeLoadHardening:
928 case Attribute::NoStackProtect:
929 case Attribute::StackProtect:
930 case Attribute::StackProtectReq:
931 case Attribute::StackProtectStrong:
932 case Attribute::StrictFP:
933 case Attribute::UWTable:
934 case Attribute::NoCfCheck:
935 case Attribute::MustProgress:
936 break;
937 }
938
939 newFunction->addFnAttr(Attr);
940 }
941 newFunction->getBasicBlockList().push_back(newRootNode);
942
943 // Create an iterator to name all of the arguments we inserted.
944 Function::arg_iterator AI = newFunction->arg_begin();
945
946 // Rewrite all users of the inputs in the extracted region to use the
947 // arguments (or appropriate addressing into struct) instead.
948 for (unsigned i = 0, e = inputs.size(); i != e; ++i) {
20
Assuming 'i' is not equal to 'e'
21
Loop condition is true. Entering loop body
949 Value *RewriteVal;
950 if (AggregateArgs
21.1
Field 'AggregateArgs' is true
) {
22
Taking true branch
951 Value *Idx[2];
952 Idx[0] = Constant::getNullValue(Type::getInt32Ty(header->getContext()));
953 Idx[1] = ConstantInt::get(Type::getInt32Ty(header->getContext()), i);
954 Instruction *TI = newFunction->begin()->getTerminator();
955 GetElementPtrInst *GEP = GetElementPtrInst::Create(
956 StructTy, &*AI, Idx, "gep_" + inputs[i]->getName(), TI);
957 RewriteVal = new LoadInst(StructTy->getElementType(i), GEP,
23
Called C++ object pointer is null
958 "loadgep_" + inputs[i]->getName(), TI);
959 } else
960 RewriteVal = &*AI++;
961
962 std::vector<User *> Users(inputs[i]->user_begin(), inputs[i]->user_end());
963 for (User *use : Users)
964 if (Instruction *inst = dyn_cast<Instruction>(use))
965 if (Blocks.count(inst->getParent()))
966 inst->replaceUsesOfWith(inputs[i], RewriteVal);
967 }
968
969 // Set names for input and output arguments.
970 if (!AggregateArgs) {
971 AI = newFunction->arg_begin();
972 for (unsigned i = 0, e = inputs.size(); i != e; ++i, ++AI)
973 AI->setName(inputs[i]->getName());
974 for (unsigned i = 0, e = outputs.size(); i != e; ++i, ++AI)
975 AI->setName(outputs[i]->getName()+".out");
976 }
977
978 // Rewrite branches to basic blocks outside of the loop to new dummy blocks
979 // within the new function. This must be done before we lose track of which
980 // blocks were originally in the code region.
981 std::vector<User *> Users(header->user_begin(), header->user_end());
982 for (auto &U : Users)
983 // The BasicBlock which contains the branch is not in the region
984 // modify the branch target to a new block
985 if (Instruction *I = dyn_cast<Instruction>(U))
986 if (I->isTerminator() && I->getFunction() == oldFunction &&
987 !Blocks.count(I->getParent()))
988 I->replaceUsesOfWith(header, newHeader);
989
990 return newFunction;
991}
992
993/// Erase lifetime.start markers which reference inputs to the extraction
994/// region, and insert the referenced memory into \p LifetimesStart.
995///
996/// The extraction region is defined by a set of blocks (\p Blocks), and a set
997/// of allocas which will be moved from the caller function into the extracted
998/// function (\p SunkAllocas).
999static void eraseLifetimeMarkersOnInputs(const SetVector<BasicBlock *> &Blocks,
1000 const SetVector<Value *> &SunkAllocas,
1001 SetVector<Value *> &LifetimesStart) {
1002 for (BasicBlock *BB : Blocks) {
1003 for (auto It = BB->begin(), End = BB->end(); It != End;) {
1004 auto *II = dyn_cast<IntrinsicInst>(&*It);
1005 ++It;
1006 if (!II || !II->isLifetimeStartOrEnd())
1007 continue;
1008
1009 // Get the memory operand of the lifetime marker. If the underlying
1010 // object is a sunk alloca, or is otherwise defined in the extraction
1011 // region, the lifetime marker must not be erased.
1012 Value *Mem = II->getOperand(1)->stripInBoundsOffsets();
1013 if (SunkAllocas.count(Mem) || definedInRegion(Blocks, Mem))
1014 continue;
1015
1016 if (II->getIntrinsicID() == Intrinsic::lifetime_start)
1017 LifetimesStart.insert(Mem);
1018 II->eraseFromParent();
1019 }
1020 }
1021}
1022
1023/// Insert lifetime start/end markers surrounding the call to the new function
1024/// for objects defined in the caller.
1025static void insertLifetimeMarkersSurroundingCall(
1026 Module *M, ArrayRef<Value *> LifetimesStart, ArrayRef<Value *> LifetimesEnd,
1027 CallInst *TheCall) {
1028 LLVMContext &Ctx = M->getContext();
1029 auto Int8PtrTy = Type::getInt8PtrTy(Ctx);
1030 auto NegativeOne = ConstantInt::getSigned(Type::getInt64Ty(Ctx), -1);
1031 Instruction *Term = TheCall->getParent()->getTerminator();
1032
1033 // The memory argument to a lifetime marker must be a i8*. Cache any bitcasts
1034 // needed to satisfy this requirement so they may be reused.
1035 DenseMap<Value *, Value *> Bitcasts;
1036
1037 // Emit lifetime markers for the pointers given in \p Objects. Insert the
1038 // markers before the call if \p InsertBefore, and after the call otherwise.
1039 auto insertMarkers = [&](Function *MarkerFunc, ArrayRef<Value *> Objects,
1040 bool InsertBefore) {
1041 for (Value *Mem : Objects) {
1042 assert((!isa<Instruction>(Mem) || cast<Instruction>(Mem)->getFunction() ==(((!isa<Instruction>(Mem) || cast<Instruction>(Mem
)->getFunction() == TheCall->getFunction()) && "Input memory not defined in original function"
) ? static_cast<void> (0) : __assert_fail ("(!isa<Instruction>(Mem) || cast<Instruction>(Mem)->getFunction() == TheCall->getFunction()) && \"Input memory not defined in original function\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1044, __PRETTY_FUNCTION__))
1043 TheCall->getFunction()) &&(((!isa<Instruction>(Mem) || cast<Instruction>(Mem
)->getFunction() == TheCall->getFunction()) && "Input memory not defined in original function"
) ? static_cast<void> (0) : __assert_fail ("(!isa<Instruction>(Mem) || cast<Instruction>(Mem)->getFunction() == TheCall->getFunction()) && \"Input memory not defined in original function\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1044, __PRETTY_FUNCTION__))
1044 "Input memory not defined in original function")(((!isa<Instruction>(Mem) || cast<Instruction>(Mem
)->getFunction() == TheCall->getFunction()) && "Input memory not defined in original function"
) ? static_cast<void> (0) : __assert_fail ("(!isa<Instruction>(Mem) || cast<Instruction>(Mem)->getFunction() == TheCall->getFunction()) && \"Input memory not defined in original function\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1044, __PRETTY_FUNCTION__))
;
1045 Value *&MemAsI8Ptr = Bitcasts[Mem];
1046 if (!MemAsI8Ptr) {
1047 if (Mem->getType() == Int8PtrTy)
1048 MemAsI8Ptr = Mem;
1049 else
1050 MemAsI8Ptr =
1051 CastInst::CreatePointerCast(Mem, Int8PtrTy, "lt.cast", TheCall);
1052 }
1053
1054 auto Marker = CallInst::Create(MarkerFunc, {NegativeOne, MemAsI8Ptr});
1055 if (InsertBefore)
1056 Marker->insertBefore(TheCall);
1057 else
1058 Marker->insertBefore(Term);
1059 }
1060 };
1061
1062 if (!LifetimesStart.empty()) {
1063 auto StartFn = llvm::Intrinsic::getDeclaration(
1064 M, llvm::Intrinsic::lifetime_start, Int8PtrTy);
1065 insertMarkers(StartFn, LifetimesStart, /*InsertBefore=*/true);
1066 }
1067
1068 if (!LifetimesEnd.empty()) {
1069 auto EndFn = llvm::Intrinsic::getDeclaration(
1070 M, llvm::Intrinsic::lifetime_end, Int8PtrTy);
1071 insertMarkers(EndFn, LifetimesEnd, /*InsertBefore=*/false);
1072 }
1073}
1074
1075/// emitCallAndSwitchStatement - This method sets up the caller side by adding
1076/// the call instruction, splitting any PHI nodes in the header block as
1077/// necessary.
1078CallInst *CodeExtractor::emitCallAndSwitchStatement(Function *newFunction,
1079 BasicBlock *codeReplacer,
1080 ValueSet &inputs,
1081 ValueSet &outputs) {
1082 // Emit a call to the new function, passing in: *pointer to struct (if
1083 // aggregating parameters), or plan inputs and allocated memory for outputs
1084 std::vector<Value *> params, StructValues, ReloadOutputs, Reloads;
1085
1086 Module *M = newFunction->getParent();
1087 LLVMContext &Context = M->getContext();
1088 const DataLayout &DL = M->getDataLayout();
1089 CallInst *call = nullptr;
1090
1091 // Add inputs as params, or to be filled into the struct
1092 unsigned ArgNo = 0;
1093 SmallVector<unsigned, 1> SwiftErrorArgs;
1094 for (Value *input : inputs) {
1095 if (AggregateArgs)
1096 StructValues.push_back(input);
1097 else {
1098 params.push_back(input);
1099 if (input->isSwiftError())
1100 SwiftErrorArgs.push_back(ArgNo);
1101 }
1102 ++ArgNo;
1103 }
1104
1105 // Create allocas for the outputs
1106 for (Value *output : outputs) {
1107 if (AggregateArgs) {
1108 StructValues.push_back(output);
1109 } else {
1110 AllocaInst *alloca =
1111 new AllocaInst(output->getType(), DL.getAllocaAddrSpace(),
1112 nullptr, output->getName() + ".loc",
1113 &codeReplacer->getParent()->front().front());
1114 ReloadOutputs.push_back(alloca);
1115 params.push_back(alloca);
1116 }
1117 }
1118
1119 StructType *StructArgTy = nullptr;
1120 AllocaInst *Struct = nullptr;
1121 if (AggregateArgs && (inputs.size() + outputs.size() > 0)) {
1122 std::vector<Type *> ArgTypes;
1123 for (ValueSet::iterator v = StructValues.begin(),
1124 ve = StructValues.end(); v != ve; ++v)
1125 ArgTypes.push_back((*v)->getType());
1126
1127 // Allocate a struct at the beginning of this function
1128 StructArgTy = StructType::get(newFunction->getContext(), ArgTypes);
1129 Struct = new AllocaInst(StructArgTy, DL.getAllocaAddrSpace(), nullptr,
1130 "structArg",
1131 &codeReplacer->getParent()->front().front());
1132 params.push_back(Struct);
1133
1134 for (unsigned i = 0, e = inputs.size(); i != e; ++i) {
1135 Value *Idx[2];
1136 Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
1137 Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), i);
1138 GetElementPtrInst *GEP = GetElementPtrInst::Create(
1139 StructArgTy, Struct, Idx, "gep_" + StructValues[i]->getName());
1140 codeReplacer->getInstList().push_back(GEP);
1141 new StoreInst(StructValues[i], GEP, codeReplacer);
1142 }
1143 }
1144
1145 // Emit the call to the function
1146 call = CallInst::Create(newFunction, params,
1147 NumExitBlocks > 1 ? "targetBlock" : "");
1148 // Add debug location to the new call, if the original function has debug
1149 // info. In that case, the terminator of the entry block of the extracted
1150 // function contains the first debug location of the extracted function,
1151 // set in extractCodeRegion.
1152 if (codeReplacer->getParent()->getSubprogram()) {
1153 if (auto DL = newFunction->getEntryBlock().getTerminator()->getDebugLoc())
1154 call->setDebugLoc(DL);
1155 }
1156 codeReplacer->getInstList().push_back(call);
1157
1158 // Set swifterror parameter attributes.
1159 for (unsigned SwiftErrArgNo : SwiftErrorArgs) {
1160 call->addParamAttr(SwiftErrArgNo, Attribute::SwiftError);
1161 newFunction->addParamAttr(SwiftErrArgNo, Attribute::SwiftError);
1162 }
1163
1164 Function::arg_iterator OutputArgBegin = newFunction->arg_begin();
1165 unsigned FirstOut = inputs.size();
1166 if (!AggregateArgs)
1167 std::advance(OutputArgBegin, inputs.size());
1168
1169 // Reload the outputs passed in by reference.
1170 for (unsigned i = 0, e = outputs.size(); i != e; ++i) {
1171 Value *Output = nullptr;
1172 if (AggregateArgs) {
1173 Value *Idx[2];
1174 Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
1175 Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), FirstOut + i);
1176 GetElementPtrInst *GEP = GetElementPtrInst::Create(
1177 StructArgTy, Struct, Idx, "gep_reload_" + outputs[i]->getName());
1178 codeReplacer->getInstList().push_back(GEP);
1179 Output = GEP;
1180 } else {
1181 Output = ReloadOutputs[i];
1182 }
1183 LoadInst *load = new LoadInst(outputs[i]->getType(), Output,
1184 outputs[i]->getName() + ".reload",
1185 codeReplacer);
1186 Reloads.push_back(load);
1187 std::vector<User *> Users(outputs[i]->user_begin(), outputs[i]->user_end());
1188 for (unsigned u = 0, e = Users.size(); u != e; ++u) {
1189 Instruction *inst = cast<Instruction>(Users[u]);
1190 if (!Blocks.count(inst->getParent()))
1191 inst->replaceUsesOfWith(outputs[i], load);
1192 }
1193 }
1194
1195 // Now we can emit a switch statement using the call as a value.
1196 SwitchInst *TheSwitch =
1197 SwitchInst::Create(Constant::getNullValue(Type::getInt16Ty(Context)),
1198 codeReplacer, 0, codeReplacer);
1199
1200 // Since there may be multiple exits from the original region, make the new
1201 // function return an unsigned, switch on that number. This loop iterates
1202 // over all of the blocks in the extracted region, updating any terminator
1203 // instructions in the to-be-extracted region that branch to blocks that are
1204 // not in the region to be extracted.
1205 std::map<BasicBlock *, BasicBlock *> ExitBlockMap;
1206
1207 unsigned switchVal = 0;
1208 for (BasicBlock *Block : Blocks) {
1209 Instruction *TI = Block->getTerminator();
1210 for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
1211 if (!Blocks.count(TI->getSuccessor(i))) {
1212 BasicBlock *OldTarget = TI->getSuccessor(i);
1213 // add a new basic block which returns the appropriate value
1214 BasicBlock *&NewTarget = ExitBlockMap[OldTarget];
1215 if (!NewTarget) {
1216 // If we don't already have an exit stub for this non-extracted
1217 // destination, create one now!
1218 NewTarget = BasicBlock::Create(Context,
1219 OldTarget->getName() + ".exitStub",
1220 newFunction);
1221 unsigned SuccNum = switchVal++;
1222
1223 Value *brVal = nullptr;
1224 switch (NumExitBlocks) {
1225 case 0:
1226 case 1: break; // No value needed.
1227 case 2: // Conditional branch, return a bool
1228 brVal = ConstantInt::get(Type::getInt1Ty(Context), !SuccNum);
1229 break;
1230 default:
1231 brVal = ConstantInt::get(Type::getInt16Ty(Context), SuccNum);
1232 break;
1233 }
1234
1235 ReturnInst::Create(Context, brVal, NewTarget);
1236
1237 // Update the switch instruction.
1238 TheSwitch->addCase(ConstantInt::get(Type::getInt16Ty(Context),
1239 SuccNum),
1240 OldTarget);
1241 }
1242
1243 // rewrite the original branch instruction with this new target
1244 TI->setSuccessor(i, NewTarget);
1245 }
1246 }
1247
1248 // Store the arguments right after the definition of output value.
1249 // This should be proceeded after creating exit stubs to be ensure that invoke
1250 // result restore will be placed in the outlined function.
1251 Function::arg_iterator OAI = OutputArgBegin;
1252 for (unsigned i = 0, e = outputs.size(); i != e; ++i) {
1253 auto *OutI = dyn_cast<Instruction>(outputs[i]);
1254 if (!OutI)
1255 continue;
1256
1257 // Find proper insertion point.
1258 BasicBlock::iterator InsertPt;
1259 // In case OutI is an invoke, we insert the store at the beginning in the
1260 // 'normal destination' BB. Otherwise we insert the store right after OutI.
1261 if (auto *InvokeI = dyn_cast<InvokeInst>(OutI))
1262 InsertPt = InvokeI->getNormalDest()->getFirstInsertionPt();
1263 else if (auto *Phi = dyn_cast<PHINode>(OutI))
1264 InsertPt = Phi->getParent()->getFirstInsertionPt();
1265 else
1266 InsertPt = std::next(OutI->getIterator());
1267
1268 Instruction *InsertBefore = &*InsertPt;
1269 assert((InsertBefore->getFunction() == newFunction ||(((InsertBefore->getFunction() == newFunction || Blocks.count
(InsertBefore->getParent())) && "InsertPt should be in new function"
) ? static_cast<void> (0) : __assert_fail ("(InsertBefore->getFunction() == newFunction || Blocks.count(InsertBefore->getParent())) && \"InsertPt should be in new function\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1271, __PRETTY_FUNCTION__))
1270 Blocks.count(InsertBefore->getParent())) &&(((InsertBefore->getFunction() == newFunction || Blocks.count
(InsertBefore->getParent())) && "InsertPt should be in new function"
) ? static_cast<void> (0) : __assert_fail ("(InsertBefore->getFunction() == newFunction || Blocks.count(InsertBefore->getParent())) && \"InsertPt should be in new function\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1271, __PRETTY_FUNCTION__))
1271 "InsertPt should be in new function")(((InsertBefore->getFunction() == newFunction || Blocks.count
(InsertBefore->getParent())) && "InsertPt should be in new function"
) ? static_cast<void> (0) : __assert_fail ("(InsertBefore->getFunction() == newFunction || Blocks.count(InsertBefore->getParent())) && \"InsertPt should be in new function\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1271, __PRETTY_FUNCTION__))
;
1272 assert(OAI != newFunction->arg_end() &&((OAI != newFunction->arg_end() && "Number of output arguments should match "
"the amount of defined values") ? static_cast<void> (0
) : __assert_fail ("OAI != newFunction->arg_end() && \"Number of output arguments should match \" \"the amount of defined values\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1274, __PRETTY_FUNCTION__))
1273 "Number of output arguments should match "((OAI != newFunction->arg_end() && "Number of output arguments should match "
"the amount of defined values") ? static_cast<void> (0
) : __assert_fail ("OAI != newFunction->arg_end() && \"Number of output arguments should match \" \"the amount of defined values\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1274, __PRETTY_FUNCTION__))
1274 "the amount of defined values")((OAI != newFunction->arg_end() && "Number of output arguments should match "
"the amount of defined values") ? static_cast<void> (0
) : __assert_fail ("OAI != newFunction->arg_end() && \"Number of output arguments should match \" \"the amount of defined values\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1274, __PRETTY_FUNCTION__))
;
1275 if (AggregateArgs) {
1276 Value *Idx[2];
1277 Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
1278 Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), FirstOut + i);
1279 GetElementPtrInst *GEP = GetElementPtrInst::Create(
1280 StructArgTy, &*OAI, Idx, "gep_" + outputs[i]->getName(),
1281 InsertBefore);
1282 new StoreInst(outputs[i], GEP, InsertBefore);
1283 // Since there should be only one struct argument aggregating
1284 // all the output values, we shouldn't increment OAI, which always
1285 // points to the struct argument, in this case.
1286 } else {
1287 new StoreInst(outputs[i], &*OAI, InsertBefore);
1288 ++OAI;
1289 }
1290 }
1291
1292 // Now that we've done the deed, simplify the switch instruction.
1293 Type *OldFnRetTy = TheSwitch->getParent()->getParent()->getReturnType();
1294 switch (NumExitBlocks) {
1295 case 0:
1296 // There are no successors (the block containing the switch itself), which
1297 // means that previously this was the last part of the function, and hence
1298 // this should be rewritten as a `ret'
1299
1300 // Check if the function should return a value
1301 if (OldFnRetTy->isVoidTy()) {
1302 ReturnInst::Create(Context, nullptr, TheSwitch); // Return void
1303 } else if (OldFnRetTy == TheSwitch->getCondition()->getType()) {
1304 // return what we have
1305 ReturnInst::Create(Context, TheSwitch->getCondition(), TheSwitch);
1306 } else {
1307 // Otherwise we must have code extracted an unwind or something, just
1308 // return whatever we want.
1309 ReturnInst::Create(Context,
1310 Constant::getNullValue(OldFnRetTy), TheSwitch);
1311 }
1312
1313 TheSwitch->eraseFromParent();
1314 break;
1315 case 1:
1316 // Only a single destination, change the switch into an unconditional
1317 // branch.
1318 BranchInst::Create(TheSwitch->getSuccessor(1), TheSwitch);
1319 TheSwitch->eraseFromParent();
1320 break;
1321 case 2:
1322 BranchInst::Create(TheSwitch->getSuccessor(1), TheSwitch->getSuccessor(2),
1323 call, TheSwitch);
1324 TheSwitch->eraseFromParent();
1325 break;
1326 default:
1327 // Otherwise, make the default destination of the switch instruction be one
1328 // of the other successors.
1329 TheSwitch->setCondition(call);
1330 TheSwitch->setDefaultDest(TheSwitch->getSuccessor(NumExitBlocks));
1331 // Remove redundant case
1332 TheSwitch->removeCase(SwitchInst::CaseIt(TheSwitch, NumExitBlocks-1));
1333 break;
1334 }
1335
1336 // Insert lifetime markers around the reloads of any output values. The
1337 // allocas output values are stored in are only in-use in the codeRepl block.
1338 insertLifetimeMarkersSurroundingCall(M, ReloadOutputs, ReloadOutputs, call);
1339
1340 return call;
1341}
1342
1343void CodeExtractor::moveCodeToFunction(Function *newFunction) {
1344 Function *oldFunc = (*Blocks.begin())->getParent();
1345 Function::BasicBlockListType &oldBlocks = oldFunc->getBasicBlockList();
1346 Function::BasicBlockListType &newBlocks = newFunction->getBasicBlockList();
1347
1348 for (BasicBlock *Block : Blocks) {
1349 // Delete the basic block from the old function, and the list of blocks
1350 oldBlocks.remove(Block);
1351
1352 // Insert this basic block into the new function
1353 newBlocks.push_back(Block);
1354 }
1355}
1356
1357void CodeExtractor::calculateNewCallTerminatorWeights(
1358 BasicBlock *CodeReplacer,
1359 DenseMap<BasicBlock *, BlockFrequency> &ExitWeights,
1360 BranchProbabilityInfo *BPI) {
1361 using Distribution = BlockFrequencyInfoImplBase::Distribution;
1362 using BlockNode = BlockFrequencyInfoImplBase::BlockNode;
1363
1364 // Update the branch weights for the exit block.
1365 Instruction *TI = CodeReplacer->getTerminator();
1366 SmallVector<unsigned, 8> BranchWeights(TI->getNumSuccessors(), 0);
1367
1368 // Block Frequency distribution with dummy node.
1369 Distribution BranchDist;
1370
1371 SmallVector<BranchProbability, 4> EdgeProbabilities(
1372 TI->getNumSuccessors(), BranchProbability::getUnknown());
1373
1374 // Add each of the frequencies of the successors.
1375 for (unsigned i = 0, e = TI->getNumSuccessors(); i < e; ++i) {
1376 BlockNode ExitNode(i);
1377 uint64_t ExitFreq = ExitWeights[TI->getSuccessor(i)].getFrequency();
1378 if (ExitFreq != 0)
1379 BranchDist.addExit(ExitNode, ExitFreq);
1380 else
1381 EdgeProbabilities[i] = BranchProbability::getZero();
1382 }
1383
1384 // Check for no total weight.
1385 if (BranchDist.Total == 0) {
1386 BPI->setEdgeProbability(CodeReplacer, EdgeProbabilities);
1387 return;
1388 }
1389
1390 // Normalize the distribution so that they can fit in unsigned.
1391 BranchDist.normalize();
1392
1393 // Create normalized branch weights and set the metadata.
1394 for (unsigned I = 0, E = BranchDist.Weights.size(); I < E; ++I) {
1395 const auto &Weight = BranchDist.Weights[I];
1396
1397 // Get the weight and update the current BFI.
1398 BranchWeights[Weight.TargetNode.Index] = Weight.Amount;
1399 BranchProbability BP(Weight.Amount, BranchDist.Total);
1400 EdgeProbabilities[Weight.TargetNode.Index] = BP;
1401 }
1402 BPI->setEdgeProbability(CodeReplacer, EdgeProbabilities);
1403 TI->setMetadata(
1404 LLVMContext::MD_prof,
1405 MDBuilder(TI->getContext()).createBranchWeights(BranchWeights));
1406}
1407
1408/// Erase debug info intrinsics which refer to values in \p F but aren't in
1409/// \p F.
1410static void eraseDebugIntrinsicsWithNonLocalRefs(Function &F) {
1411 for (Instruction &I : instructions(F)) {
1412 SmallVector<DbgVariableIntrinsic *, 4> DbgUsers;
1413 findDbgUsers(DbgUsers, &I);
1414 for (DbgVariableIntrinsic *DVI : DbgUsers)
1415 if (DVI->getFunction() != &F)
1416 DVI->eraseFromParent();
1417 }
1418}
1419
1420/// Fix up the debug info in the old and new functions by pointing line
1421/// locations and debug intrinsics to the new subprogram scope, and by deleting
1422/// intrinsics which point to values outside of the new function.
1423static void fixupDebugInfoPostExtraction(Function &OldFunc, Function &NewFunc,
1424 CallInst &TheCall) {
1425 DISubprogram *OldSP = OldFunc.getSubprogram();
1426 LLVMContext &Ctx = OldFunc.getContext();
1427
1428 if (!OldSP) {
1429 // Erase any debug info the new function contains.
1430 stripDebugInfo(NewFunc);
1431 // Make sure the old function doesn't contain any non-local metadata refs.
1432 eraseDebugIntrinsicsWithNonLocalRefs(NewFunc);
1433 return;
1434 }
1435
1436 // Create a subprogram for the new function. Leave out a description of the
1437 // function arguments, as the parameters don't correspond to anything at the
1438 // source level.
1439 assert(OldSP->getUnit() && "Missing compile unit for subprogram")((OldSP->getUnit() && "Missing compile unit for subprogram"
) ? static_cast<void> (0) : __assert_fail ("OldSP->getUnit() && \"Missing compile unit for subprogram\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1439, __PRETTY_FUNCTION__))
;
1440 DIBuilder DIB(*OldFunc.getParent(), /*AllowUnresolved=*/false,
1441 OldSP->getUnit());
1442 auto SPType = DIB.createSubroutineType(DIB.getOrCreateTypeArray(None));
1443 DISubprogram::DISPFlags SPFlags = DISubprogram::SPFlagDefinition |
1444 DISubprogram::SPFlagOptimized |
1445 DISubprogram::SPFlagLocalToUnit;
1446 auto NewSP = DIB.createFunction(
1447 OldSP->getUnit(), NewFunc.getName(), NewFunc.getName(), OldSP->getFile(),
1448 /*LineNo=*/0, SPType, /*ScopeLine=*/0, DINode::FlagZero, SPFlags);
1449 NewFunc.setSubprogram(NewSP);
1450
1451 // Debug intrinsics in the new function need to be updated in one of two
1452 // ways:
1453 // 1) They need to be deleted, because they describe a value in the old
1454 // function.
1455 // 2) They need to point to fresh metadata, e.g. because they currently
1456 // point to a variable in the wrong scope.
1457 SmallDenseMap<DINode *, DINode *> RemappedMetadata;
1458 SmallVector<Instruction *, 4> DebugIntrinsicsToDelete;
1459 for (Instruction &I : instructions(NewFunc)) {
1460 auto *DII = dyn_cast<DbgInfoIntrinsic>(&I);
1461 if (!DII)
1462 continue;
1463
1464 // Point the intrinsic to a fresh label within the new function.
1465 if (auto *DLI = dyn_cast<DbgLabelInst>(&I)) {
1466 DILabel *OldLabel = DLI->getLabel();
1467 DINode *&NewLabel = RemappedMetadata[OldLabel];
1468 if (!NewLabel)
1469 NewLabel = DILabel::get(Ctx, NewSP, OldLabel->getName(),
1470 OldLabel->getFile(), OldLabel->getLine());
1471 DLI->setArgOperand(0, MetadataAsValue::get(Ctx, NewLabel));
1472 continue;
1473 }
1474
1475 // If the location isn't a constant or an instruction, delete the
1476 // intrinsic.
1477 auto *DVI = cast<DbgVariableIntrinsic>(DII);
1478 Value *Location = DVI->getVariableLocation();
1479 if (!Location ||
1480 (!isa<Constant>(Location) && !isa<Instruction>(Location))) {
1481 DebugIntrinsicsToDelete.push_back(DVI);
1482 continue;
1483 }
1484
1485 // If the variable location is an instruction but isn't in the new
1486 // function, delete the intrinsic.
1487 Instruction *LocationInst = dyn_cast<Instruction>(Location);
1488 if (LocationInst && LocationInst->getFunction() != &NewFunc) {
1489 DebugIntrinsicsToDelete.push_back(DVI);
1490 continue;
1491 }
1492
1493 // Point the intrinsic to a fresh variable within the new function.
1494 DILocalVariable *OldVar = DVI->getVariable();
1495 DINode *&NewVar = RemappedMetadata[OldVar];
1496 if (!NewVar)
1497 NewVar = DIB.createAutoVariable(
1498 NewSP, OldVar->getName(), OldVar->getFile(), OldVar->getLine(),
1499 OldVar->getType(), /*AlwaysPreserve=*/false, DINode::FlagZero,
1500 OldVar->getAlignInBits());
1501 DVI->setArgOperand(1, MetadataAsValue::get(Ctx, NewVar));
1502 }
1503 for (auto *DII : DebugIntrinsicsToDelete)
1504 DII->eraseFromParent();
1505 DIB.finalizeSubprogram(NewSP);
1506
1507 // Fix up the scope information attached to the line locations in the new
1508 // function.
1509 for (Instruction &I : instructions(NewFunc)) {
1510 if (const DebugLoc &DL = I.getDebugLoc())
1511 I.setDebugLoc(DebugLoc::get(DL.getLine(), DL.getCol(), NewSP));
1512
1513 // Loop info metadata may contain line locations. Fix them up.
1514 auto updateLoopInfoLoc = [&Ctx,
1515 NewSP](const DILocation &Loc) -> DILocation * {
1516 return DILocation::get(Ctx, Loc.getLine(), Loc.getColumn(), NewSP,
1517 nullptr);
1518 };
1519 updateLoopMetadataDebugLocations(I, updateLoopInfoLoc);
1520 }
1521 if (!TheCall.getDebugLoc())
1522 TheCall.setDebugLoc(DebugLoc::get(0, 0, OldSP));
1523
1524 eraseDebugIntrinsicsWithNonLocalRefs(NewFunc);
1525}
1526
1527Function *
1528CodeExtractor::extractCodeRegion(const CodeExtractorAnalysisCache &CEAC) {
1529 if (!isEligible())
1530 return nullptr;
1531
1532 // Assumption: this is a single-entry code region, and the header is the first
1533 // block in the region.
1534 BasicBlock *header = *Blocks.begin();
1535 Function *oldFunction = header->getParent();
1536
1537 // Calculate the entry frequency of the new function before we change the root
1538 // block.
1539 BlockFrequency EntryFreq;
1540 if (BFI) {
1541 assert(BPI && "Both BPI and BFI are required to preserve profile info")((BPI && "Both BPI and BFI are required to preserve profile info"
) ? static_cast<void> (0) : __assert_fail ("BPI && \"Both BPI and BFI are required to preserve profile info\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1541, __PRETTY_FUNCTION__))
;
1542 for (BasicBlock *Pred : predecessors(header)) {
1543 if (Blocks.count(Pred))
1544 continue;
1545 EntryFreq +=
1546 BFI->getBlockFreq(Pred) * BPI->getEdgeProbability(Pred, header);
1547 }
1548 }
1549
1550 // Remove @llvm.assume calls that will be moved to the new function from the
1551 // old function's assumption cache.
1552 for (BasicBlock *Block : Blocks) {
1553 for (auto It = Block->begin(), End = Block->end(); It != End;) {
1554 Instruction *I = &*It;
1555 ++It;
1556
1557 if (match(I, m_Intrinsic<Intrinsic::assume>())) {
1558 if (AC)
1559 AC->unregisterAssumption(cast<CallInst>(I));
1560 I->eraseFromParent();
1561 }
1562 }
1563 }
1564
1565 // If we have any return instructions in the region, split those blocks so
1566 // that the return is not in the region.
1567 splitReturnBlocks();
1568
1569 // Calculate the exit blocks for the extracted region and the total exit
1570 // weights for each of those blocks.
1571 DenseMap<BasicBlock *, BlockFrequency> ExitWeights;
1572 SmallPtrSet<BasicBlock *, 1> ExitBlocks;
1573 for (BasicBlock *Block : Blocks) {
1574 for (succ_iterator SI = succ_begin(Block), SE = succ_end(Block); SI != SE;
1575 ++SI) {
1576 if (!Blocks.count(*SI)) {
1577 // Update the branch weight for this successor.
1578 if (BFI) {
1579 BlockFrequency &BF = ExitWeights[*SI];
1580 BF += BFI->getBlockFreq(Block) * BPI->getEdgeProbability(Block, *SI);
1581 }
1582 ExitBlocks.insert(*SI);
1583 }
1584 }
1585 }
1586 NumExitBlocks = ExitBlocks.size();
1587
1588 // If we have to split PHI nodes of the entry or exit blocks, do so now.
1589 severSplitPHINodesOfEntry(header);
1590 severSplitPHINodesOfExits(ExitBlocks);
1591
1592 // This takes place of the original loop
1593 BasicBlock *codeReplacer = BasicBlock::Create(header->getContext(),
1594 "codeRepl", oldFunction,
1595 header);
1596
1597 // The new function needs a root node because other nodes can branch to the
1598 // head of the region, but the entry node of a function cannot have preds.
1599 BasicBlock *newFuncRoot = BasicBlock::Create(header->getContext(),
1600 "newFuncRoot");
1601 auto *BranchI = BranchInst::Create(header);
1602 // If the original function has debug info, we have to add a debug location
1603 // to the new branch instruction from the artificial entry block.
1604 // We use the debug location of the first instruction in the extracted
1605 // blocks, as there is no other equivalent line in the source code.
1606 if (oldFunction->getSubprogram()) {
1607 any_of(Blocks, [&BranchI](const BasicBlock *BB) {
1608 return any_of(*BB, [&BranchI](const Instruction &I) {
1609 if (!I.getDebugLoc())
1610 return false;
1611 BranchI->setDebugLoc(I.getDebugLoc());
1612 return true;
1613 });
1614 });
1615 }
1616 newFuncRoot->getInstList().push_back(BranchI);
1617
1618 ValueSet inputs, outputs, SinkingCands, HoistingCands;
1619 BasicBlock *CommonExit = nullptr;
1620 findAllocas(CEAC, SinkingCands, HoistingCands, CommonExit);
1621 assert(HoistingCands.empty() || CommonExit)((HoistingCands.empty() || CommonExit) ? static_cast<void>
(0) : __assert_fail ("HoistingCands.empty() || CommonExit", "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1621, __PRETTY_FUNCTION__))
;
1622
1623 // Find inputs to, outputs from the code region.
1624 findInputsOutputs(inputs, outputs, SinkingCands);
1625
1626 // Now sink all instructions which only have non-phi uses inside the region.
1627 // Group the allocas at the start of the block, so that any bitcast uses of
1628 // the allocas are well-defined.
1629 AllocaInst *FirstSunkAlloca = nullptr;
1630 for (auto *II : SinkingCands) {
1631 if (auto *AI = dyn_cast<AllocaInst>(II)) {
1632 AI->moveBefore(*newFuncRoot, newFuncRoot->getFirstInsertionPt());
1633 if (!FirstSunkAlloca)
1634 FirstSunkAlloca = AI;
1635 }
1636 }
1637 assert((SinkingCands.empty() || FirstSunkAlloca) &&(((SinkingCands.empty() || FirstSunkAlloca) && "Did not expect a sink candidate without any allocas"
) ? static_cast<void> (0) : __assert_fail ("(SinkingCands.empty() || FirstSunkAlloca) && \"Did not expect a sink candidate without any allocas\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1638, __PRETTY_FUNCTION__))
1638 "Did not expect a sink candidate without any allocas")(((SinkingCands.empty() || FirstSunkAlloca) && "Did not expect a sink candidate without any allocas"
) ? static_cast<void> (0) : __assert_fail ("(SinkingCands.empty() || FirstSunkAlloca) && \"Did not expect a sink candidate without any allocas\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1638, __PRETTY_FUNCTION__))
;
1639 for (auto *II : SinkingCands) {
1640 if (!isa<AllocaInst>(II)) {
1641 cast<Instruction>(II)->moveAfter(FirstSunkAlloca);
1642 }
1643 }
1644
1645 if (!HoistingCands.empty()) {
1646 auto *HoistToBlock = findOrCreateBlockForHoisting(CommonExit);
1647 Instruction *TI = HoistToBlock->getTerminator();
1648 for (auto *II : HoistingCands)
1649 cast<Instruction>(II)->moveBefore(TI);
1650 }
1651
1652 // Collect objects which are inputs to the extraction region and also
1653 // referenced by lifetime start markers within it. The effects of these
1654 // markers must be replicated in the calling function to prevent the stack
1655 // coloring pass from merging slots which store input objects.
1656 ValueSet LifetimesStart;
1657 eraseLifetimeMarkersOnInputs(Blocks, SinkingCands, LifetimesStart);
1658
1659 // Construct new function based on inputs/outputs & add allocas for all defs.
1660 Function *newFunction =
1661 constructFunction(inputs, outputs, header, newFuncRoot, codeReplacer,
1662 oldFunction, oldFunction->getParent());
1663
1664 // Update the entry count of the function.
1665 if (BFI) {
1666 auto Count = BFI->getProfileCountFromFreq(EntryFreq.getFrequency());
1667 if (Count.hasValue())
1668 newFunction->setEntryCount(
1669 ProfileCount(Count.getValue(), Function::PCT_Real)); // FIXME
1670 BFI->setBlockFreq(codeReplacer, EntryFreq.getFrequency());
1671 }
1672
1673 CallInst *TheCall =
1674 emitCallAndSwitchStatement(newFunction, codeReplacer, inputs, outputs);
1675
1676 moveCodeToFunction(newFunction);
1677
1678 // Replicate the effects of any lifetime start/end markers which referenced
1679 // input objects in the extraction region by placing markers around the call.
1680 insertLifetimeMarkersSurroundingCall(
1681 oldFunction->getParent(), LifetimesStart.getArrayRef(), {}, TheCall);
1682
1683 // Propagate personality info to the new function if there is one.
1684 if (oldFunction->hasPersonalityFn())
1685 newFunction->setPersonalityFn(oldFunction->getPersonalityFn());
1686
1687 // Update the branch weights for the exit block.
1688 if (BFI && NumExitBlocks > 1)
1689 calculateNewCallTerminatorWeights(codeReplacer, ExitWeights, BPI);
1690
1691 // Loop over all of the PHI nodes in the header and exit blocks, and change
1692 // any references to the old incoming edge to be the new incoming edge.
1693 for (BasicBlock::iterator I = header->begin(); isa<PHINode>(I); ++I) {
1694 PHINode *PN = cast<PHINode>(I);
1695 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
1696 if (!Blocks.count(PN->getIncomingBlock(i)))
1697 PN->setIncomingBlock(i, newFuncRoot);
1698 }
1699
1700 for (BasicBlock *ExitBB : ExitBlocks)
1701 for (PHINode &PN : ExitBB->phis()) {
1702 Value *IncomingCodeReplacerVal = nullptr;
1703 for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1704 // Ignore incoming values from outside of the extracted region.
1705 if (!Blocks.count(PN.getIncomingBlock(i)))
1706 continue;
1707
1708 // Ensure that there is only one incoming value from codeReplacer.
1709 if (!IncomingCodeReplacerVal) {
1710 PN.setIncomingBlock(i, codeReplacer);
1711 IncomingCodeReplacerVal = PN.getIncomingValue(i);
1712 } else
1713 assert(IncomingCodeReplacerVal == PN.getIncomingValue(i) &&((IncomingCodeReplacerVal == PN.getIncomingValue(i) &&
"PHI has two incompatbile incoming values from codeRepl") ? static_cast
<void> (0) : __assert_fail ("IncomingCodeReplacerVal == PN.getIncomingValue(i) && \"PHI has two incompatbile incoming values from codeRepl\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1714, __PRETTY_FUNCTION__))
1714 "PHI has two incompatbile incoming values from codeRepl")((IncomingCodeReplacerVal == PN.getIncomingValue(i) &&
"PHI has two incompatbile incoming values from codeRepl") ? static_cast
<void> (0) : __assert_fail ("IncomingCodeReplacerVal == PN.getIncomingValue(i) && \"PHI has two incompatbile incoming values from codeRepl\""
, "/build/llvm-toolchain-snapshot-12.0.0~++20201102111116+1ed2ca68191/llvm/lib/Transforms/Utils/CodeExtractor.cpp"
, 1714, __PRETTY_FUNCTION__))
;
1715 }
1716 }
1717
1718 fixupDebugInfoPostExtraction(*oldFunction, *newFunction, *TheCall);
1719
1720 // Mark the new function `noreturn` if applicable. Terminators which resume
1721 // exception propagation are treated as returning instructions. This is to
1722 // avoid inserting traps after calls to outlined functions which unwind.
1723 bool doesNotReturn = none_of(*newFunction, [](const BasicBlock &BB) {
1724 const Instruction *Term = BB.getTerminator();
1725 return isa<ReturnInst>(Term) || isa<ResumeInst>(Term);
1726 });
1727 if (doesNotReturn)
1728 newFunction->setDoesNotReturn();
1729
1730 LLVM_DEBUG(if (verifyFunction(*newFunction, &errs())) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (verifyFunction(*newFunction, &errs
())) { newFunction->dump(); report_fatal_error("verification of newFunction failed!"
); }; } } while (false)
1731 newFunction->dump();do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (verifyFunction(*newFunction, &errs
())) { newFunction->dump(); report_fatal_error("verification of newFunction failed!"
); }; } } while (false)
1732 report_fatal_error("verification of newFunction failed!");do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (verifyFunction(*newFunction, &errs
())) { newFunction->dump(); report_fatal_error("verification of newFunction failed!"
); }; } } while (false)
1733 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (verifyFunction(*newFunction, &errs
())) { newFunction->dump(); report_fatal_error("verification of newFunction failed!"
); }; } } while (false)
;
1734 LLVM_DEBUG(if (verifyFunction(*oldFunction))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (verifyFunction(*oldFunction)) report_fatal_error
("verification of oldFunction failed!"); } } while (false)
1735 report_fatal_error("verification of oldFunction failed!"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (verifyFunction(*oldFunction)) report_fatal_error
("verification of oldFunction failed!"); } } while (false)
;
1736 LLVM_DEBUG(if (AC && verifyAssumptionCache(*oldFunction, *newFunction, AC))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (AC && verifyAssumptionCache
(*oldFunction, *newFunction, AC)) report_fatal_error("Stale Asumption cache for old Function!"
); } } while (false)
1737 report_fatal_error("Stale Asumption cache for old Function!"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("code-extractor")) { if (AC && verifyAssumptionCache
(*oldFunction, *newFunction, AC)) report_fatal_error("Stale Asumption cache for old Function!"
); } } while (false)
;
1738 return newFunction;
1739}
1740
1741bool CodeExtractor::verifyAssumptionCache(const Function &OldFunc,
1742 const Function &NewFunc,
1743 AssumptionCache *AC) {
1744 for (auto AssumeVH : AC->assumptions()) {
1745 auto *I = dyn_cast_or_null<CallInst>(AssumeVH);
1746 if (!I)
1747 continue;
1748
1749 // There shouldn't be any llvm.assume intrinsics in the new function.
1750 if (I->getFunction() != &OldFunc)
1751 return true;
1752
1753 // There shouldn't be any stale affected values in the assumption cache
1754 // that were previously in the old function, but that have now been moved
1755 // to the new function.
1756 for (auto AffectedValVH : AC->assumptionsFor(I->getOperand(0))) {
1757 auto *AffectedCI = dyn_cast_or_null<CallInst>(AffectedValVH);
1758 if (!AffectedCI)
1759 continue;
1760 if (AffectedCI->getFunction() != &OldFunc)
1761 return true;
1762 auto *AssumedInst = cast<Instruction>(AffectedCI->getOperand(0));
1763 if (AssumedInst->getFunction() != &OldFunc)
1764 return true;
1765 }
1766 }
1767 return false;
1768}