Youwei Wang has posted comments on this change. Change subject: IMPALA-2809: Improve ByteSwap with builtin function or SSSE3 or AVX2. ......................................................................
Patch Set 19: (1 comment) http://gerrit.cloudera.org:8080/#/c/3081/17/be/src/util/bit-util.inline.h File be/src/util/bit-util.inline.h: Line 156: 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15); > I think you can make this constexpr and static without the run-time penalty Hi Jim. Thank you for proposing this idea. After some experiments, I found out: both clang++(v3.8) and gcc(4.9.2) don't support "constexp static __m256i mask256i = _mm256_set_epi" nor "const static __m256i mask256i = _mm256_set_epi". For both two compilers, "_mm256_set_epi8" is recognized as non-constexpr function. So I am afraid only static modifier can be applied here at this moment. -- To view, visit http://gerrit.cloudera.org:8080/3081 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I392ed5a8d5683f30f161282c228c1aedd7b648c1 Gerrit-PatchSet: 19 Gerrit-Project: Impala Gerrit-Branch: cdh5-trunk Gerrit-Owner: Youwei Wang <[email protected]> Gerrit-Reviewer: Alex Behm <[email protected]> Gerrit-Reviewer: Jim Apple <[email protected]> Gerrit-Reviewer: Marcel Kornacker <[email protected]> Gerrit-Reviewer: Mostafa Mokhtar <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-Reviewer: Youwei Wang <[email protected]> Gerrit-HasComments: Yes
