diff options
| -rw-r--r-- | llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp | 5 | ||||
| -rw-r--r-- | llvm/test/Transforms/Mem2Reg/pr37632-unreachable-list-of-stores.ll | 20 |
2 files changed, 25 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp index e161690f5bf..86e15bbd7f2 100644 --- a/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp +++ b/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp @@ -511,6 +511,11 @@ static bool promoteSingleBlockAlloca(AllocaInst *AI, const AllocaInfo &Info, !isKnownNonZero(ReplVal, DL, 0, AC, LI, &DT)) addAssumeNonNull(AC, LI); + // If the replacement value is the load, this must occur in unreachable + // code. + if (ReplVal == LI) + ReplVal = UndefValue::get(LI->getType()); + LI->replaceAllUsesWith(ReplVal); } diff --git a/llvm/test/Transforms/Mem2Reg/pr37632-unreachable-list-of-stores.ll b/llvm/test/Transforms/Mem2Reg/pr37632-unreachable-list-of-stores.ll new file mode 100644 index 00000000000..bb4c0f1d57f --- /dev/null +++ b/llvm/test/Transforms/Mem2Reg/pr37632-unreachable-list-of-stores.ll @@ -0,0 +1,20 @@ +; RUN: opt -mem2reg < %s -S | FileCheck %s + + +; CHECK-LABEL: void @patatino() +; CHECK-NEXT: ret void + +; CHECK-LABEL: cantreachme: +; CHECK-NEXT: %dec = add nsw i32 undef, -1 +; CHECK-NEXT: br label %cantreachme + +define void @patatino() { + %a = alloca i32, align 4 + ret void +cantreachme: + %dec = add nsw i32 %tmp, -1 + store i32 %dec, i32* %a + store i32 %tmp, i32* %a + %tmp = load i32, i32* %a + br label %cantreachme +} |
