https://gcc.gnu.org/g:971f8d5b5fd5ce9ccdc742332dfff6ed833a6ea3
commit r17-1730-g971f8d5b5fd5ce9ccdc742332dfff6ed833a6ea3 Author: Pan Li <[email protected]> Date: Tue Jun 16 13:40:39 2026 +0800 Match: Support unsigned scalar SAT_MUL form 13 This patch would like to try to match the the unsigned SAT_MUL form 13, aka below #define DEF_SAT_U_MUL_FMT_13(NT, WT) \ NT __attribute__((noinline)) \ sat_u_mul_##NT##_from_##WT##_fmt_13 (NT a, NT b) \ { \ WT x = (WT)a * (WT)b; \ if ((x >> sizeof(a) * 8) != 0) \ return (NT)-1; \ else \ return (NT)x; \ } while WT is uint128_t, uint64_t, uint32_t and uint16_t, and NT is uint64_t, uint32_t, uint16_t or uint8_t. gcc/ChangeLog: * match-sat-alu.pd: Add pattern for unsigned scalar SAT_MUL form 13. Signed-off-by: Pan Li <[email protected]> Diff: --- gcc/match-sat-alu.pd | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/gcc/match-sat-alu.pd b/gcc/match-sat-alu.pd index 6145a0c99484..c47d73f958d6 100644 --- a/gcc/match-sat-alu.pd +++ b/gcc/match-sat-alu.pd @@ -524,6 +524,31 @@ along with GCC; see the file COPYING3. If not see bool c2_is_type_precision_p = c2 == prec; } (if (widen_prec > prec && c2_is_type_precision_p && c4_is_max_p))))) + (match (unsigned_integer_sat_mul @0 @1) + /* SAT_U_MUL (X, Y) = { + WT x = (WT)a * (WT)b; + if ((x >> sizeof(a) * 8) != 0) + return (T)-1; + else + return (T)x; + } + while WT is uint128_t, T is uint8_t, uint16_t, uint32_t or uint64_t. */ + (convert (cond^ (ne (rshift (mult:c@3 (convert @0) (convert @1)) + INTEGER_CST@2) + integer_zerop) + INTEGER_CST@4 @3)) + (if (types_match (type, @0, @1) && tree_fits_uhwi_p (@2)) + (with + { + unsigned prec = TYPE_PRECISION (type); + unsigned widen_prec = TYPE_PRECISION (TREE_TYPE (@3)); + wide_int c4 = wi::to_wide (@4); + wide_int max = wi::mask (prec, false, widen_prec); + bool c4_is_max_p = wi::eq_p (c4, max); + unsigned c2 = tree_to_uhwi (@2); + bool c2_is_type_precision_p = c2 == prec; + } + (if (widen_prec > prec && c2_is_type_precision_p && c4_is_max_p))))) (match (unsigned_integer_sat_mul @0 @1) /* SAT_U_MUL (X, Y) = { WT x = (WT)a * (WT)b;
