https://gcc.gnu.org/g:cdc06c5d808d338b240b4f50ae33cb43b71ccb40
commit r17-5754-gcdc06c5d808d338b240b4f50ae33cb43b71ccb40 Author: Uros Bizjak <[email protected]> Date: Fri Oct 30 10:16:50 2026 +0100 i386: Use separate unspecs for CRC32 widths [PR128310] The CRC32 insns used a single UNSPEC_CRC32 for all operand widths. When the second operand is a constant, which carries no mode, the QI, HI and SI forms become identical unspec expressions, so CSE merges crc32 results of different widths and e.g. _mm_crc32_u16 (c, 0x7f) == _mm_crc32_u32 (c, 0x7f) folds to 1. Use a distinct unspec for each width. Also add the 64-bit zero-extended form of crc32b. Assisted-by: Claude Sonnet 5.5 PR target/128310 gcc/ChangeLog: * config/i386/i386.md (UNSPEC_CRC32): Remove. (UNSPEC_CRC32B, UNSPEC_CRC32W) (UNSPEC_CRC32L, UNSPEC_CRC32Q): New. (sse4_2_crc32qi): Rename from sse4_2_crc32<mode>. Use UNSPEC_CRC32B. (*sse4_2_crc32qi_zext): New insn. (sse4_2_crc32hi): New insn. (sse4_2_crc32si): Ditto. (sse4_2_crc32di): Use UNSPEC_CRC32Q. gcc/testsuite/ChangeLog: * gcc.target/i386/pr128310.c: New test. Diff: --- gcc/config/i386/i386.md | 60 ++++++++++++++++++++++++++------ gcc/testsuite/gcc.target/i386/pr128310.c | 33 ++++++++++++++++++ 2 files changed, 83 insertions(+), 10 deletions(-) diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index bc225020890b..15ff3d0902ae 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -191,7 +191,10 @@ UNSPEC_ROUND ;; For CRC32 support - UNSPEC_CRC32 + UNSPEC_CRC32B + UNSPEC_CRC32W + UNSPEC_CRC32L + UNSPEC_CRC32Q ;; For LZCNT support UNSPEC_LZCNT @@ -30678,34 +30681,71 @@ (symbol_ref "memory_address_length (operands[0], false)")) (set_attr "memory" "none")]) -(define_insn "sse4_2_crc32<mode>" +(define_insn "sse4_2_crc32qi" [(set (match_operand:SI 0 "register_operand" "=r") (unspec:SI [(match_operand:SI 1 "register_operand" "0") - (match_operand:SWI124 2 "nonimmediate_operand" "<r>m")] - UNSPEC_CRC32))] + (match_operand:QI 2 "nonimmediate_operand" "qm")] + UNSPEC_CRC32B))] "TARGET_CRC32" - "crc32{<imodesuffix>}\t{%2, %0|%0, %2}" + "crc32{b}\t{%2, %0|%0, %2}" [(set_attr "type" "sselog1") (set_attr "prefix_rep" "1") (set_attr "prefix_extra" "1") - (set (attr "prefix_data16") - (if_then_else (match_operand:HI 2) - (const_string "1") - (const_string "*"))) (set (attr "prefix_rex") (if_then_else (match_operand:QI 2 "ext_QIreg_operand") (const_string "1") (const_string "*"))) (set_attr "mode" "SI")]) +(define_insn "*sse4_2_crc32qi_zext" + [(set (match_operand:DI 0 "register_operand" "=r") + (zero_extend:DI + (unspec:SI + [(match_operand:SI 1 "register_operand" "0") + (match_operand:QI 2 "nonimmediate_operand" "qm")] + UNSPEC_CRC32B)))] + "TARGET_64BIT && TARGET_CRC32" + "crc32{b}\t{%2, %0|%0, %2}" + [(set_attr "type" "sselog1") + (set_attr "prefix_rep" "1") + (set_attr "prefix_extra" "1") + (set_attr "mode" "SI")]) + +(define_insn "sse4_2_crc32hi" + [(set (match_operand:SI 0 "register_operand" "=r") + (unspec:SI + [(match_operand:SI 1 "register_operand" "0") + (match_operand:HI 2 "nonimmediate_operand" "rm")] + UNSPEC_CRC32W))] + "TARGET_CRC32" + "crc32{w}\t{%2, %0|%0, %2}" + [(set_attr "type" "sselog1") + (set_attr "prefix_rep" "1") + (set_attr "prefix_extra" "1") + (set_attr "prefix_data16" "1") + (set_attr "mode" "SI")]) + +(define_insn "sse4_2_crc32si" + [(set (match_operand:SI 0 "register_operand" "=r") + (unspec:SI + [(match_operand:SI 1 "register_operand" "0") + (match_operand:SI 2 "nonimmediate_operand" "rm")] + UNSPEC_CRC32L))] + "TARGET_CRC32" + "crc32{l}\t{%2, %0|%0, %2}" + [(set_attr "type" "sselog1") + (set_attr "prefix_rep" "1") + (set_attr "prefix_extra" "1") + (set_attr "mode" "SI")]) + (define_insn "sse4_2_crc32di" [(set (match_operand:DI 0 "register_operand" "=r") (zero_extend:DI (unspec:SI [(match_operand:SI 1 "register_operand" "0") (match_operand:DI 2 "nonimmediate_operand" "rm")] - UNSPEC_CRC32)))] + UNSPEC_CRC32Q)))] "TARGET_64BIT && TARGET_CRC32" "crc32{q}\t{%2, %0|%0, %2}" [(set_attr "type" "sselog1") diff --git a/gcc/testsuite/gcc.target/i386/pr128310.c b/gcc/testsuite/gcc.target/i386/pr128310.c new file mode 100644 index 000000000000..d90475971cf8 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr128310.c @@ -0,0 +1,33 @@ +/* PR target/128310 */ +/* { dg-do run } */ +/* { dg-options "-O2 -mcrc32" } */ +/* { dg-require-effective-target sse4 } */ + +#include "sse4_2-check.h" +#include <immintrin.h> +#include <stdint.h> + +__attribute__((noipa)) int bh (uint32_t c) +{ return _mm_crc32_u8 (c, 0x7f) == _mm_crc32_u16 (c, 0x7f); } + +__attribute__((noipa)) int bs (uint32_t c) +{ return _mm_crc32_u8 (c, 0x7f) == _mm_crc32_u32 (c, 0x7f); } + +__attribute__((noipa)) int hs (uint32_t c) +{ return _mm_crc32_u16 (c, 0x7f) == _mm_crc32_u32 (c, 0x7f); } + +#ifdef __x86_64__ +__attribute__((noipa)) int bq (uint32_t c) +{ return _mm_crc32_u8 (c, 0x7f) == _mm_crc32_u64 (c, 0x7f); } +#endif + +static void +sse4_2_test (void) +{ + if (bh (7) || bs (7) || hs (7)) + __builtin_abort (); +#ifdef __x86_64__ + if (bq (7)) + __builtin_abort (); +#endif +}
