From 7aa0ad65ce03b59515fe0089f7cd8250c50cdb25 Mon Sep 17 00:00:00 2001 From: Tim Shen Date: Wed, 8 Jun 2016 19:42:32 +0000 Subject: [MemCpyOpt] Do not exchange llvm.lifetime.start and llvm.memcpy Reviewers: iteratee Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D21087 llvm-svn: 272192 --- llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp') diff --git a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp index 3c421d2365d..3ab892f7529 100644 --- a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp +++ b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp @@ -788,6 +788,11 @@ bool MemCpyOpt::performCallSlotOptzn(Instruction *cpy, // src only holds uninitialized values at the moment of the call, meaning that // the memcpy can be discarded rather than moved. + // Lifetime marks shouldn't be operated on. + if (Function *F = C->getCalledFunction()) + if (F->isIntrinsic() && F->getIntrinsicID() == Intrinsic::lifetime_start) + return false; + // Deliberately get the source and destination with bitcasts stripped away, // because we'll need to do type comparisons based on the underlying type. CallSite CS(C); -- cgit v1.2.3