From a4cf325e41fca33c7ce7deef39a7bcf25fb38266 Mon Sep 17 00:00:00 2001 From: Tom Stellard Date: Tue, 17 Mar 2015 20:42:08 +0000 Subject: [PATCH] Merging r214336: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ------------------------------------------------------------------------ r214336 | rafael.espindola | 2014-07-30 17:04:00 -0400 (Wed, 30 Jul 2014) | 9 lines SimplifyCFG: Avoid miscompilations due to removed lifetime intrinsics. The lifetime intrinsics need some work in order to make it clear which optimizations are or are not valid. For now dropping this optimization avoids a miscompilation. Patch by Björn Steinbrink. ------------------------------------------------------------------------ git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@232544 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Utils/SimplifyCFG.cpp | 2 +- test/Transforms/SimplifyCFG/lifetime.ll | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp index 24bb63bb60a..1c62559739f 100644 --- a/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/lib/Transforms/Utils/SimplifyCFG.cpp @@ -4008,7 +4008,7 @@ bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI, IRBuilder<> &Builder){ return true; // If the Terminator is the only non-phi instruction, simplify the block. - BasicBlock::iterator I = BB->getFirstNonPHIOrDbgOrLifetime(); + BasicBlock::iterator I = BB->getFirstNonPHIOrDbg(); if (I->isTerminator() && BB != &BB->getParent()->getEntryBlock() && TryToSimplifyUncondBranchFromEmptyBlock(BB)) return true; diff --git a/test/Transforms/SimplifyCFG/lifetime.ll b/test/Transforms/SimplifyCFG/lifetime.ll index b7942217253..7c66be52950 100644 --- a/test/Transforms/SimplifyCFG/lifetime.ll +++ b/test/Transforms/SimplifyCFG/lifetime.ll @@ -1,11 +1,11 @@ ; RUN: opt < %s -simplifycfg -S | FileCheck %s -; Test that a lifetime intrinsic doesn't prevent us from simplifying this. +; Test that a lifetime intrinsic isn't removed because that would change semantics ; CHECK: foo ; CHECK: entry: -; CHECK-NOT: bb0: -; CHECK-NOT: bb1: +; CHECK: bb0: +; CHECK: bb1: ; CHECK: ret define void @foo(i1 %x) { entry: