diff options
| author | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2013-06-28 21:10:25 +0000 |
|---|---|---|
| committer | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2013-06-28 21:10:25 +0000 |
| commit | e187512bde9fd090a78924928a0b8793e3d87cbb (patch) | |
| tree | 81b77a6ae98b1c6879123b9ba3cbf23960b09dc5 /lib/Support | |
| parent | 4025fa5b85cf7e3df47c40c2a03e05afe44841fa (diff) | |
| download | external_llvm-e187512bde9fd090a78924928a0b8793e3d87cbb.zip external_llvm-e187512bde9fd090a78924928a0b8793e3d87cbb.tar.gz external_llvm-e187512bde9fd090a78924928a0b8793e3d87cbb.tar.bz2 | |
Eliminate an assortment of undefined behavior.
Hopefully, this fixes the PPC64 buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185218 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Support')
| -rw-r--r-- | lib/Support/BlockFrequency.cpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/lib/Support/BlockFrequency.cpp b/lib/Support/BlockFrequency.cpp index 6e4d6b1..8de517f 100644 --- a/lib/Support/BlockFrequency.cpp +++ b/lib/Support/BlockFrequency.cpp @@ -47,9 +47,13 @@ static uint64_t div96bit(uint64_t W[2], uint32_t D) { uint64_t x = W[1]; unsigned i; + // This is really a 64-bit division. + if (!x) + return y / D; + // This long division algorithm automatically saturates on overflow. for (i = 0; i < 64 && x; ++i) { - uint32_t t = (int)x >> 31; + uint32_t t = -((x >> 31) & 1); // Splat bit 31 to bits 0-31. x = (x << 1) | (y >> 63); y = y << 1; if ((x | t) >= D) { |