| Message ID | 20231014005713.2702564-1-pinskia@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | MATCH: [PR111432] Simplify `a & (x | CST)` to a when we know that (a & ~CST) == 0 | expand |
On Sat, Oct 14, 2023 at 2:57 AM Andrew Pinski <pinskia@gmail.com> wrote: > > This adds the simplification `a & (x | CST)` to a when we know that > `(a & ~CST) == 0`. In a similar fashion as `a & CST` is handle. > > I looked into handling `a | (x & CST)` but that I don't see any decent > simplifications happening. > > OK? Bootstrapped and tested on x86_linux-gnu with no regressions. OK. > PR tree-optimization/111432 > > gcc/ChangeLog: > > * match.pd (`a & (x | CST)`): New pattern. > > gcc/testsuite/ChangeLog: > > * gcc.dg/tree-ssa/bitops-7.c: New test. > --- > gcc/match.pd | 8 ++++++++ > gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c | 24 ++++++++++++++++++++++++ > 2 files changed, 32 insertions(+) > create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c > > diff --git a/gcc/match.pd b/gcc/match.pd > index 51e5065d086..45624f3dcb4 100644 > --- a/gcc/match.pd > +++ b/gcc/match.pd > @@ -1550,6 +1550,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) > (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) > && wi::bit_and_not (get_nonzero_bits (@0), wi::to_wide (@1)) == 0) > @0)) > + > +/* `a & (x | CST)` -> a if we know that (a & ~CST) == 0 */ > +(simplify > + (bit_and:c SSA_NAME@0 (bit_ior @1 INTEGER_CST@2)) > + (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) > + && wi::bit_and_not (get_nonzero_bits (@0), wi::to_wide (@2)) == 0) > + @0)) > + > /* x | C -> C if we know that x & ~C == 0. */ > (simplify > (bit_ior SSA_NAME@0 INTEGER_CST@1) > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c b/gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c > new file mode 100644 > index 00000000000..7fb18db3a11 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c > @@ -0,0 +1,24 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O1 -fdump-tree-optimized-raw" } */ > +/* PR tree-optimization/111432 */ > + > +int > +foo3(int c, int bb) > +{ > + if ((bb & ~3)!=0) __builtin_unreachable(); > + return (bb & (c|3)); > +} > + > +int > +foo_bool(int c, _Bool bb) > +{ > + return (bb & (c|7)); > +} > + > +/* Both of these functions should be able to remove the `IOR` and `AND` > + as the only bits that are non-zero for bb is set on the other side > + of the `AND`. > + */ > + > +/* { dg-final { scan-tree-dump-not "bit_ior_expr, " "optimized" } } */ > +/* { dg-final { scan-tree-dump-not "bit_and_expr, " "optimized" } } */ > -- > 2.39.3 >
diff --git a/gcc/match.pd b/gcc/match.pd index 51e5065d086..45624f3dcb4 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -1550,6 +1550,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) && wi::bit_and_not (get_nonzero_bits (@0), wi::to_wide (@1)) == 0) @0)) + +/* `a & (x | CST)` -> a if we know that (a & ~CST) == 0 */ +(simplify + (bit_and:c SSA_NAME@0 (bit_ior @1 INTEGER_CST@2)) + (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) + && wi::bit_and_not (get_nonzero_bits (@0), wi::to_wide (@2)) == 0) + @0)) + /* x | C -> C if we know that x & ~C == 0. */ (simplify (bit_ior SSA_NAME@0 INTEGER_CST@1) diff --git a/gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c b/gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c new file mode 100644 index 00000000000..7fb18db3a11 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/bitops-7.c @@ -0,0 +1,24 @@ +/* { dg-do compile } */ +/* { dg-options "-O1 -fdump-tree-optimized-raw" } */ +/* PR tree-optimization/111432 */ + +int +foo3(int c, int bb) +{ + if ((bb & ~3)!=0) __builtin_unreachable(); + return (bb & (c|3)); +} + +int +foo_bool(int c, _Bool bb) +{ + return (bb & (c|7)); +} + +/* Both of these functions should be able to remove the `IOR` and `AND` + as the only bits that are non-zero for bb is set on the other side + of the `AND`. + */ + +/* { dg-final { scan-tree-dump-not "bit_ior_expr, " "optimized" } } */ +/* { dg-final { scan-tree-dump-not "bit_and_expr, " "optimized" } } */