diff options
author | Evgeniy Stepanov <eugeni.stepanov@gmail.com> | 2014-07-10 12:45:56 +0000 |
---|---|---|
committer | Evgeniy Stepanov <eugeni.stepanov@gmail.com> | 2014-07-10 12:45:56 +0000 |
commit | b1e6561b90176255765474f4bb8ead7112f790c3 (patch) | |
tree | 4bd7cacf69d5947dab92f9e97406ae3734c23c7a /lib | |
parent | 53aa313f962535087170613bdd18766c54918e90 (diff) | |
download | compiler-rt-b1e6561b90176255765474f4bb8ead7112f790c3.tar.gz |
[msan] Fix performance issue in fast_memset.
Fast path was never triggered when called from __msan_poison.
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@212715 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r-- | lib/msan/msan_interceptors.cc | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/lib/msan/msan_interceptors.cc b/lib/msan/msan_interceptors.cc index 79c7fc17b..339469088 100644 --- a/lib/msan/msan_interceptors.cc +++ b/lib/msan/msan_interceptors.cc @@ -1264,13 +1264,14 @@ void *fast_memset(void *ptr, int c, SIZE_T n) { // hack until we have a really fast internal_memset if (sizeof(uptr) == 8 && (n % 8) == 0 && - ((uptr)ptr % 8) == 0 && - (c == 0 || c == -1)) { - // Printf("memset %p %zd %x\n", ptr, n, c); - uptr to_store = c ? -1L : 0L; + ((uptr)ptr % 8) == 0) { + uptr c8 = (unsigned)c & 0xFF; + c8 = (c8 << 8) | c8; + c8 = (c8 << 16) | c8; + c8 = (c8 << 32) | c8; uptr *p = (uptr*)ptr; for (SIZE_T i = 0; i < n / 8; i++) - p[i] = to_store; + p[i] = c8; return ptr; } return internal_memset(ptr, c, n); |