[InstCombine] Disable strcmp->memcmp transform for MSan.
authorMatt Morehouse <mascasa@google.com>
Wed, 19 Sep 2018 19:37:24 +0000 (19:37 +0000)
committerMatt Morehouse <mascasa@google.com>
Wed, 19 Sep 2018 19:37:24 +0000 (19:37 +0000)
commite62fc3d0b6ce923dcbc29eeb6ebc5808e6724f90
treee5fadc259b3b063b9ddb6a12d82ce1c5b67a9c81
parenta4526d77c9921c86a29889fc09de17f7d5ccb210
[InstCombine] Disable strcmp->memcmp transform for MSan.

Summary:
The strcmp->memcmp transform can make the resulting memcmp read
uninitialized data, which MSan doesn't like.

Resolves https://github.com/google/sanitizers/issues/993.

Reviewers: eugenis, xbolva00

Reviewed By: eugenis

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D52272

llvm-svn: 342582
llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
llvm/test/Transforms/InstCombine/strcmp-memcmp.ll