On Tue, Aug 8, 2023 at 12:44 AM Richard Biener via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > On Tue, Aug 8, 2023 at 2:55 AM Andrew Pinski via Gcc-patches > <gcc-patches@gcc.gnu.org> wrote: > > > > This adds a simple match pattern for this case. > > I noticed it a couple of different places. > > One while I was looking at code generation of a parser and > > also while I was looking at locations where bitwise_inverted_equal_p > > should be used more. > > > > OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions. > > > > PR tree-optimization/110937 > > PR tree-optimization/100798 > > > > gcc/ChangeLog: > > > > * match.pd (`a ? ~b : b`): Handle this > > case. > > > > gcc/testsuite/ChangeLog: > > > > * gcc.dg/tree-ssa/bool-14.c: New test. > > * gcc.dg/tree-ssa/bool-15.c: New test. > > * gcc.dg/tree-ssa/phi-opt-33.c: New test. > > * gcc.dg/tree-ssa/20030709-2.c: Update testcase > > so `a ? -1 : 0` is not used to hit the match > > pattern. > > --- > > gcc/match.pd | 13 +++++++++++++ > > gcc/testsuite/gcc.dg/tree-ssa/20030709-2.c | 5 +++-- > > gcc/testsuite/gcc.dg/tree-ssa/bool-14.c | 15 +++++++++++++++ > > gcc/testsuite/gcc.dg/tree-ssa/bool-15.c | 18 ++++++++++++++++++ > > gcc/testsuite/gcc.dg/tree-ssa/phi-opt-33.c | 13 +++++++++++++ > > 5 files changed, 62 insertions(+), 2 deletions(-) > > create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/bool-14.c > > create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/bool-15.c > > create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/phi-opt-33.c > > > > diff --git a/gcc/match.pd b/gcc/match.pd > > index 9b4819e5be7..f887c517c81 100644 > > --- a/gcc/match.pd > > +++ b/gcc/match.pd > > @@ -6460,6 +6460,19 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) > > (if (cmp == NE_EXPR) > > { constant_boolean_node (true, type); }))))))) > > > > +#if GIMPLE > > +/* a?~t:t -> (-(a))^t */ > > +(simplify > > + (cond @0 @1 @2) > > + (if (bitwise_inverted_equal_p (@1, @2)) > > I'm not sure if that can ever match a not INTEGRAL_TYPE_P > but we can have vector typed @1 and @2 and then the > TYPE_PRECISION ask below would be wrong. So can you > add > > INTEGRAL_TYPE_P (type) > && bitwise_in... > > if only for clarity? > > > + (with { > > + auto prec = TYPE_PRECISION (type); > > + auto unsign = TYPE_UNSIGNED (type); > > + tree inttype = build_nonstandard_integer_type (prec, unsign); > > + } > > + (convert (bit_xor (negate (convert:inttype @0)) (convert:inttype > > @2)))))) > > so we don't get to know which of @1 or @2 is "simpler" (the not > explicitely inverted > operand), I suppose that's the disadvantage of using bitwise_inverted_equal_p. > I'll note that if you make bitwise_inverted_equal_p a match you'd need a :c on > the 'cond' but otherwise complexity would be the same as match patterns are > not > "inlined".
Right, The disadvantage is definitely not knowing which is "simpler". And I found a testcase which shows that but I suspect we can fix that. ``` int f(int a, int t) { int t1 = ~t; return (a=='s' ? t : t1); } ``` Basically we are missing transforming: ~(-(cast)(cmp)) into -(cast)(cmp`) Filed as PR 110949 . > > In any case, OK with the INTEGRAL_TYPE_P check. Will update the patch and commit it after a bootstrap/test. Thanks, Andrew > > Thanks, > Richard. > > > +#endif > > + > > /* Simplify pointer equality compares using PTA. */ > > (for neeq (ne eq) > > (simplify > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/20030709-2.c > > b/gcc/testsuite/gcc.dg/tree-ssa/20030709-2.c > > index 5009cd69cfe..78938f919d4 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/20030709-2.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/20030709-2.c > > @@ -29,15 +29,16 @@ union tree_node > > }; > > int make_decl_rtl (tree, int); > > void * > > -get_alias_set (t) > > +get_alias_set (t, t1) > > tree t; > > + void *t1; > > { > > long set; > > if (t->decl.rtl) > > return (t->decl.rtl->fld[1].rtmem > > ? 0 > > : (((t->decl.rtl ? t->decl.rtl: (make_decl_rtl (t, 0), > > t->decl.rtl)))->fld[1]).rtmem); > > - return (void*)-1; > > + return t1; > > } > > > > /* There should be precisely one load of ->decl.rtl. If there is > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/bool-14.c > > b/gcc/testsuite/gcc.dg/tree-ssa/bool-14.c > > new file mode 100644 > > index 00000000000..0149380a63b > > --- /dev/null > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/bool-14.c > > @@ -0,0 +1,15 @@ > > +/* { dg-do compile } */ > > +/* { dg-options "-O2 -fdump-tree-optimized-raw" } */ > > +/* PR tree-optimization/110937 */ > > + > > +_Bool f2(_Bool a, _Bool b) > > +{ > > + if (a) > > + return !b; > > + return b; > > +} > > + > > +/* We should be able to remove the conditional and convert it to an xor. */ > > +/* { dg-final { scan-tree-dump-not "gimple_cond " "optimized" } } */ > > +/* { dg-final { scan-tree-dump-not "gimple_phi " "optimized" } } */ > > +/* { dg-final { scan-tree-dump-times "bit_xor_expr, " 1 "optimized" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/bool-15.c > > b/gcc/testsuite/gcc.dg/tree-ssa/bool-15.c > > new file mode 100644 > > index 00000000000..1f496663863 > > --- /dev/null > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/bool-15.c > > @@ -0,0 +1,18 @@ > > +/* { dg-do compile } */ > > +/* { dg-options "-O2 -fdump-tree-optimized-raw" } */ > > +/* PR tree-optimization/110937 */ > > + > > +_Bool f2(int x, int y, int w, int z) > > +{ > > + _Bool a = x == y; > > + _Bool b = w == z; > > + if (a) > > + return !b; > > + return b; > > +} > > + > > +/* We should be able to remove the conditional and convert it to an xor. */ > > +/* { dg-final { scan-tree-dump-not "gimple_cond " "optimized" } } */ > > +/* { dg-final { scan-tree-dump-not "gimple_phi " "optimized" } } */ > > +/* { dg-final { scan-tree-dump-not "ne_expr, " "optimized" } } */ > > +/* { dg-final { scan-tree-dump-times "bit_xor_expr, " 1 "optimized" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-33.c > > b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-33.c > > new file mode 100644 > > index 00000000000..b79fe44187a > > --- /dev/null > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-33.c > > @@ -0,0 +1,13 @@ > > +/* { dg-do compile } */ > > +/* { dg-options "-O2 -fdump-tree-optimized-raw" } */ > > +/* PR tree-optimization/100798 */ > > + > > +int f(int a, int t) > > +{ > > + return (a=='s' ? ~t : t); > > +} > > + > > +/* This should be convert into t^-(a=='s'). */ > > +/* { dg-final { scan-tree-dump-times "bit_xor_expr, " 1 "optimized" } } */ > > +/* { dg-final { scan-tree-dump-times "negate_expr, " 1 "optimized" } } */ > > +/* { dg-final { scan-tree-dump-not "bit_not_expr, " "optimized" } } */ > > -- > > 2.31.1 > >