On Fri, Nov 12, 2021 at 04:34:27PM +0100, Jakub Jelinek via Gcc-patches wrote: > Why? When one uses 16-bit atomics, no matter what he does there will be > some HImode math (at least the atomic instruction). And the rest can be > dealt with. > > I have following patch queued for testing for this...
Bootstrapped/regtested successfully on x86_64-linux and i686-linux, ok for trunk? > 2021-11-12 Jakub Jelinek <ja...@redhat.com> > > PR target/103205 > * config/i386/sync.md (atomic_bit_test_and_set<mode>, > atomic_bit_test_and_complement<mode>, > atomic_bit_test_and_reset<mode>): Use OPTAB_WIDEN instead of > OPTAB_DIRECT. > > * gcc.target/i386/pr103205.c: New test. > > --- gcc/config/i386/sync.md.jj 2021-10-04 19:53:01.025005548 +0200 > +++ gcc/config/i386/sync.md 2021-11-12 15:27:47.387273428 +0100 > @@ -726,7 +726,7 @@ (define_expand "atomic_bit_test_and_set< > rtx result = convert_modes (<MODE>mode, QImode, tem, 1); > if (operands[4] == const0_rtx) > result = expand_simple_binop (<MODE>mode, ASHIFT, result, > - operands[2], operands[0], 0, OPTAB_DIRECT); > + operands[2], operands[0], 0, OPTAB_WIDEN); > if (result != operands[0]) > emit_move_insn (operands[0], result); > DONE; > @@ -763,7 +763,7 @@ (define_expand "atomic_bit_test_and_comp > rtx result = convert_modes (<MODE>mode, QImode, tem, 1); > if (operands[4] == const0_rtx) > result = expand_simple_binop (<MODE>mode, ASHIFT, result, > - operands[2], operands[0], 0, OPTAB_DIRECT); > + operands[2], operands[0], 0, OPTAB_WIDEN); > if (result != operands[0]) > emit_move_insn (operands[0], result); > DONE; > @@ -801,7 +801,7 @@ (define_expand "atomic_bit_test_and_rese > rtx result = convert_modes (<MODE>mode, QImode, tem, 1); > if (operands[4] == const0_rtx) > result = expand_simple_binop (<MODE>mode, ASHIFT, result, > - operands[2], operands[0], 0, OPTAB_DIRECT); > + operands[2], operands[0], 0, OPTAB_WIDEN); > if (result != operands[0]) > emit_move_insn (operands[0], result); > DONE; > --- gcc/testsuite/gcc.target/i386/pr103205.c.jj 2021-11-12 > 15:47:21.218380790 +0100 > +++ gcc/testsuite/gcc.target/i386/pr103205.c 2021-11-12 15:46:39.546980182 > +0100 > @@ -0,0 +1,11 @@ > +/* PR target/103205 */ > +/* { dg-do compile } */ > +/* { dg-options "-O2 -mtune-ctrl=^himode_math" } */ > + > +unsigned short a; > + > +unsigned short > +foo (void) > +{ > + return __sync_fetch_and_and (&a, ~1) & 1; > +} Jakub