From c5b785b91c922bbb3d5adb4b042c976bebe00e4d Mon Sep 17 00:00:00 2001 From: Chandler Carruth Date: Sat, 24 Mar 2012 22:34:23 +0000 Subject: [PATCH] Don't add the instruction about to be RAUW'ed and erased to the worklist. This can happen in theory when an instruction uses itself, such as a PHI node. This was spotted by inspection, and unfortunately I've not been able to come up with a test case that would trigger it. If anyone has ideas, let me know... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153396 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/InstructionSimplify.cpp | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp index 95d02efd789..c8fb6ae595b 100644 --- a/lib/Analysis/InstructionSimplify.cpp +++ b/lib/Analysis/InstructionSimplify.cpp @@ -2841,7 +2841,8 @@ static bool replaceAndRecursivelySimplifyImpl(Instruction *I, Value *SimpleV, if (SimpleV) { for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); UI != UE; ++UI) - Worklist.push_back(cast(*UI)); + if (*UI != I) + Worklist.push_back(cast(*UI)); // Replace the instruction with its simplified value. I->replaceAllUsesWith(SimpleV); @@ -2869,7 +2870,8 @@ static bool replaceAndRecursivelySimplifyImpl(Instruction *I, Value *SimpleV, // uses of To on the recursive step in most cases. for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); UI != UE; ++UI) - Worklist.push_back(cast(*UI)); + if (*UI != I) + Worklist.push_back(cast(*UI)); // Replace the instruction with its simplified value. I->replaceAllUsesWith(SimpleV);