On Tue, May 19, 2026 at 4:03 AM <[email protected]> wrote: > > From: Pan Li <[email protected]> > > This patch would like to try to match the the unsigned > SAT_MUL form 11, aka below > > #define DEF_SAT_U_MUL_FMT_11(NT, WT) \ > NT __attribute__((noinline)) \ > sat_u_mul_##NT##_from_##WT##_fmt_11 (NT a, NT b) \ > { \ > WT x = (WT)a * (WT)b; \ > NT max = -1; \ > bool overflow_p = x >= (WT)(max); \ > return -(NT)(overflow_p) | (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.
OK > gcc/ChangeLog: > > * match-sat-alu.pd: Add pattern for unsigned scalar > SAT_MUL form 11. > > Signed-off-by: Pan Li <[email protected]> > --- > gcc/match-sat-alu.pd | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/gcc/match-sat-alu.pd b/gcc/match-sat-alu.pd > index 483c37b6d9f..6145a0c9948 100644 > --- a/gcc/match-sat-alu.pd > +++ b/gcc/match-sat-alu.pd > @@ -548,7 +548,7 @@ along with GCC; see the file COPYING3. If not see > /* SAT_U_MUL (X, Y) = { > WT x = (WT)a * (WT)b; > NT max = -1; > - bool overflow_p = x > (WT)max; > + bool overflow_p = x > (WT)max || x > (WT)(max - 1); > return -(NT)(overflow_p) | (NT)x; > } while WT is uint128_t, uint64_t, uint32_t, uint16_t, > and T is uint64_t, uint32_t, uint16_t, uint8_t. */ > @@ -560,7 +560,12 @@ along with GCC; see the file COPYING3. If not see > unsigned prec = TYPE_PRECISION (type); > unsigned widen_prec = TYPE_PRECISION (TREE_TYPE (@3)); > wide_int max = wi::mask (prec, false, widen_prec); > - bool c2_is_max_p = wi::eq_p (wi::to_wide (@2), max); > + > + wide_int c2 = wi::to_wide (@2); > + bool c2_is_max_p = wi::eq_p (c2, max); > + > + wide_int c2_plus_one = wi::add (c2, wi::uhwi (1, widen_prec)); > + bool c2_plus_one_is_max_p = wi::eq_p (c2_plus_one, max); > } > - (if (c2_is_max_p))))) > + (if (c2_is_max_p || c2_plus_one_is_max_p))))) > ) > -- > 2.43.0 >
