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[DO_NOT_MERGE] Test PR#30716

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[DO_NOT_MERGE] Test PR#30716
luismarques wants to merge 2 commits into
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luismarques:llvm-22

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Do not merge.

The crc32 instructions are non-standard and not supported by upstream
clang.

According to perftest, this only slows things down by a few cycles

before:
I00003 crc32_perftest.c:33] CRC32 computed in 11343 cycles.
I00004 crc32_perftest.c:33] CRC32 computed in 11317 cycles.
I00005 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00006 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00007 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00008 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00009 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00010 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00011 crc32_perftest.c:33] CRC32 computed in 11314 cycles.
I00012 crc32_perftest.c:33] CRC32 computed in 11314 cycles.

after:
I00003 crc32_perftest.c:33] CRC32 computed in 11358 cycles.
I00004 crc32_perftest.c:33] CRC32 computed in 11319 cycles.
I00005 crc32_perftest.c:33] CRC32 computed in 11318 cycles.
I00006 crc32_perftest.c:33] CRC32 computed in 11318 cycles.
I00007 crc32_perftest.c:33] CRC32 computed in 11318 cycles.
I00008 crc32_perftest.c:33] CRC32 computed in 11318 cycles.
I00009 crc32_perftest.c:33] CRC32 computed in 11318 cycles.
I00010 crc32_perftest.c:33] CRC32 computed in 11318 cycles.
I00011 crc32_perftest.c:33] CRC32 computed in 11318 cycles.

Signed-off-by: Kor Nielsen <kor@google.com>
(cherry picked from commit 6a6ff0b)
@luismarques luismarques force-pushed the llvm-22 branch 6 times, most recently from 09241de to a88e19d Compare July 11, 2026 20:10
Signed-off-by: Luís Marques <luismarques@lowrisc.org>
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