diff options
| -rw-r--r-- | llvm/include/llvm/Analysis/PHITransAddr.h | 8 | ||||
| -rw-r--r-- | llvm/lib/Analysis/MemoryDependenceAnalysis.cpp | 3 | ||||
| -rw-r--r-- | llvm/lib/Analysis/PHITransAddr.cpp | 19 | ||||
| -rw-r--r-- | llvm/test/Transforms/GVN/unreachable_block_infinite_loop.ll | 29 |
4 files changed, 46 insertions, 13 deletions
diff --git a/llvm/include/llvm/Analysis/PHITransAddr.h b/llvm/include/llvm/Analysis/PHITransAddr.h index 84bb9d8008b..cbdbb88f740 100644 --- a/llvm/include/llvm/Analysis/PHITransAddr.h +++ b/llvm/include/llvm/Analysis/PHITransAddr.h @@ -75,12 +75,12 @@ public: bool IsPotentiallyPHITranslatable() const; /// PHITranslateValue - PHI translate the current address up the CFG from - /// CurBB to Pred, updating our state to reflect any needed changes. If the - /// dominator tree DT is non-null, the translated value must dominate + /// CurBB to Pred, updating our state to reflect any needed changes. If + /// 'MustDominate' is true, the translated value must dominate /// PredBB. This returns true on failure and sets Addr to null. bool PHITranslateValue(BasicBlock *CurBB, BasicBlock *PredBB, - const DominatorTree *DT); - + const DominatorTree *DT, bool MustDominate); + /// PHITranslateWithInsertion - PHI translate this value into the specified /// predecessor block, inserting a computation of the value if it is /// unavailable. diff --git a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp index 3c1826a58e6..ecc1c9bda9b 100644 --- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp +++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp @@ -1278,8 +1278,7 @@ getNonLocalPointerDepFromBB(Instruction *QueryInst, // Get the PHI translated pointer in this predecessor. This can fail if // not translatable, in which case the getAddr() returns null. PHITransAddr &PredPointer = PredList.back().second; - PredPointer.PHITranslateValue(BB, Pred, nullptr); - + PredPointer.PHITranslateValue(BB, Pred, DT, /*MustDominate=*/false); Value *PredPtrVal = PredPointer.getAddr(); // Check to see if we have already visited this pred block with another diff --git a/llvm/lib/Analysis/PHITransAddr.cpp b/llvm/lib/Analysis/PHITransAddr.cpp index 71e2cdcbb42..633d6aaad35 100644 --- a/llvm/lib/Analysis/PHITransAddr.cpp +++ b/llvm/lib/Analysis/PHITransAddr.cpp @@ -315,21 +315,26 @@ Value *PHITransAddr::PHITranslateSubExpr(Value *V, BasicBlock *CurBB, /// PHITranslateValue - PHI translate the current address up the CFG from -/// CurBB to Pred, updating our state to reflect any needed changes. If the -/// dominator tree DT is non-null, the translated value must dominate +/// CurBB to Pred, updating our state to reflect any needed changes. If +/// 'MustDominate' is true, the translated value must dominate /// PredBB. This returns true on failure and sets Addr to null. bool PHITransAddr::PHITranslateValue(BasicBlock *CurBB, BasicBlock *PredBB, - const DominatorTree *DT) { + const DominatorTree *DT, + bool MustDominate) { + assert(DT || !MustDominate); assert(Verify() && "Invalid PHITransAddr!"); - Addr = PHITranslateSubExpr(Addr, CurBB, PredBB, DT); + if (DT && DT->isReachableFromEntry(PredBB)) + Addr = + PHITranslateSubExpr(Addr, CurBB, PredBB, MustDominate ? DT : nullptr); + else + Addr = nullptr; assert(Verify() && "Invalid PHITransAddr!"); - if (DT) { + if (MustDominate) // Make sure the value is live in the predecessor. if (Instruction *Inst = dyn_cast_or_null<Instruction>(Addr)) if (!DT->dominates(Inst->getParent(), PredBB)) Addr = nullptr; - } return Addr == nullptr; } @@ -372,7 +377,7 @@ InsertPHITranslatedSubExpr(Value *InVal, BasicBlock *CurBB, // See if we have a version of this value already available and dominating // PredBB. If so, there is no need to insert a new instance of it. PHITransAddr Tmp(InVal, DL, AC); - if (!Tmp.PHITranslateValue(CurBB, PredBB, &DT)) + if (!Tmp.PHITranslateValue(CurBB, PredBB, &DT, /*MustDominate=*/true)) return Tmp.getAddr(); // If we don't have an available version of this value, it must be an diff --git a/llvm/test/Transforms/GVN/unreachable_block_infinite_loop.ll b/llvm/test/Transforms/GVN/unreachable_block_infinite_loop.ll index fca5a28b38d..a47e9e4c3a0 100644 --- a/llvm/test/Transforms/GVN/unreachable_block_infinite_loop.ll +++ b/llvm/test/Transforms/GVN/unreachable_block_infinite_loop.ll @@ -12,3 +12,32 @@ unreachable_block: ret i32 %a } +define i32 @pr23096_test0() { +entry: + br label %bb0 + +bb1: + %ptr1 = ptrtoint i32* %ptr2 to i64 + %ptr2 = inttoptr i64 %ptr1 to i32* + br i1 undef, label %bb0, label %bb1 + +bb0: + %phi = phi i32* [ undef, %entry ], [ %ptr2, %bb1 ] + %load = load i32, i32* %phi + ret i32 %load +} + +define i32 @pr23096_test1() { +entry: + br label %bb0 + +bb1: + %ptr1 = getelementptr i32, i32* %ptr2, i32 0 + %ptr2 = getelementptr i32, i32* %ptr1, i32 0 + br i1 undef, label %bb0, label %bb1 + +bb0: + %phi = phi i32* [ undef, %entry ], [ %ptr2, %bb1 ] + %load = load i32, i32* %phi + ret i32 %load +} |
