diff options
| author |  Copybara-Service <copybara-worker@google.com> | 2023-02-22 08:13:06 -0800 |
|---|---|---|
| committer | Copybara-Service <copybara-worker@google.com> | 2023-02-22 08:13:06 -0800 |
| commit | d6ea4df62db59dc1ebc1fd3b62146700640ef400 (patch) | |
| tree | a65ea233272b101048e405748df0ba892da4084e /absl/hash | |
| parent | c3b5022604551a045e383c68071d7be0a807839d (diff) | |
| parent | 32794f0a4272bd4cc7ee5306999e9ff4180278d9 (diff) | |
Merge pull request #1388 from miladfarca:fix-Read1To3-on-BE
PiperOrigin-RevId: 511499093
Change-Id: I9ea2bbc38cbe8bd9dae937626d8faac41c010b38
Diffstat (limited to 'absl/hash')
| -rw-r--r-- | absl/hash/internal/hash.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/absl/hash/internal/hash.h b/absl/hash/internal/hash.h index 89740dab..61970e0d 100644 --- a/absl/hash/internal/hash.h +++ b/absl/hash/internal/hash.h @@ -1074,6 +1074,7 @@ class ABSL_DLL MixingHashState : public HashStateBase<MixingHashState> { // Reads 1 to 3 bytes from p. Zero pads to fill uint32_t. static uint32_t Read1To3(const unsigned char* p, size_t len) { + // The trick used by this implementation is to avoid branches if possible. unsigned char mem0 = p[0]; unsigned char mem1 = p[len / 2]; unsigned char mem2 = p[len - 1]; @@ -1083,7 +1084,7 @@ class ABSL_DLL MixingHashState : public HashStateBase<MixingHashState> { unsigned char significant0 = mem0; #else unsigned char significant2 = mem0; - unsigned char significant1 = mem1; + unsigned char significant1 = len == 2 ? mem0 : mem1; unsigned char significant0 = mem2; #endif return static_cast<uint32_t>(significant0 | // |