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-rw-r--r--llvm/lib/Analysis/AliasAnalysis.cpp52
1 files changed, 2 insertions, 50 deletions
diff --git a/llvm/lib/Analysis/AliasAnalysis.cpp b/llvm/lib/Analysis/AliasAnalysis.cpp
index fa1484d57de..3f1cf6aa3f8 100644
--- a/llvm/lib/Analysis/AliasAnalysis.cpp
+++ b/llvm/lib/Analysis/AliasAnalysis.cpp
@@ -388,53 +388,6 @@ AliasAnalysis::getModRefInfo(const AtomicRMWInst *RMW, const Location &Loc) {
return ModRef;
}
-namespace {
- /// Only find pointer captures which happen before the given instruction. Uses
- /// the dominator tree to determine whether one instruction is before another.
- /// Only support the case where the Value is defined in the same basic block
- /// as the given instruction and the use.
- struct CapturesBefore : public CaptureTracker {
- CapturesBefore(const Instruction *I, DominatorTree *DT)
- : BeforeHere(I), DT(DT), Captured(false) {}
-
- void tooManyUses() override { Captured = true; }
-
- bool shouldExplore(const Use *U) override {
- Instruction *I = cast<Instruction>(U->getUser());
- BasicBlock *BB = I->getParent();
- // We explore this usage only if the usage can reach "BeforeHere".
- // If use is not reachable from entry, there is no need to explore.
- if (BeforeHere != I && !DT->isReachableFromEntry(BB))
- return false;
- // If the value is defined in the same basic block as use and BeforeHere,
- // there is no need to explore the use if BeforeHere dominates use.
- // Check whether there is a path from I to BeforeHere.
- if (BeforeHere != I && DT->dominates(BeforeHere, I) &&
- !isPotentiallyReachable(I, BeforeHere, DT))
- return false;
- return true;
- }
-
- bool captured(const Use *U) override {
- Instruction *I = cast<Instruction>(U->getUser());
- BasicBlock *BB = I->getParent();
- // Same logic as in shouldExplore.
- if (BeforeHere != I && !DT->isReachableFromEntry(BB))
- return false;
- if (BeforeHere != I && DT->dominates(BeforeHere, I) &&
- !isPotentiallyReachable(I, BeforeHere, DT))
- return false;
- Captured = true;
- return true;
- }
-
- const Instruction *BeforeHere;
- DominatorTree *DT;
-
- bool Captured;
- };
-}
-
// FIXME: this is really just shoring-up a deficiency in alias analysis.
// BasicAA isn't willing to spend linear time determining whether an alloca
// was captured before or after this particular call, while we are. However,
@@ -454,9 +407,8 @@ AliasAnalysis::callCapturesBefore(const Instruction *I,
if (!CS.getInstruction() || CS.getInstruction() == Object)
return AliasAnalysis::ModRef;
- CapturesBefore CB(I, DT);
- llvm::PointerMayBeCaptured(Object, &CB);
- if (CB.Captured)
+ if (llvm::PointerMayBeCapturedBefore(Object, /* ReturnCaptures */ true,
+ /* StoreCaptures */ true, I, DT))
return AliasAnalysis::ModRef;
unsigned ArgNo = 0;
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