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| author | Jakub Jelinek <jakub@redhat.com> | 2021-05-20 09:10:38 +0200 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2021-05-20 09:10:38 +0200 |
| commit | 2b536797f7e43c55072a3215735f5833f1d6d218 (patch) | |
| tree | ed90c10a928ec8e34b4937a84827804a7cf7c38a /gcc/match.pd | |
| parent | d15a2d261b24adcbfe5e663b15dde3df5d2b3486 (diff) | |
| download | gcc-2b536797f7e43c55072a3215735f5833f1d6d218.zip gcc-2b536797f7e43c55072a3215735f5833f1d6d218.tar.gz gcc-2b536797f7e43c55072a3215735f5833f1d6d218.tar.bz2 | |
phiopt: Simplify (X & Y) == X -> (X & ~Y) == 0 even in presence of integral conversions [PR94589]
On Wed, May 19, 2021 at 10:15:53AM +0200, Christophe Lyon via Gcc-patches wrote:
> After this update, the test fails on arm and aarch64: according to the
> logs, the optimization is still performed 14 times.
Seems this is because
if (change
&& !flag_syntax_only
&& (load_extend_op (TYPE_MODE (TREE_TYPE (and0)))
== ZERO_EXTEND))
{
tree uns = unsigned_type_for (TREE_TYPE (and0));
and0 = fold_convert_loc (loc, uns, and0);
and1 = fold_convert_loc (loc, uns, and1);
}
in fold-const.c adds on these targets extra casts that prevent the
optimizations.
2021-05-20 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/94589
* match.pd ((X & Y) == X -> (X & ~Y) == 0): Simplify even in presence
of integral conversions.
Diffstat (limited to 'gcc/match.pd')
| -rw-r--r-- | gcc/match.pd | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index cdb8763..e01bb7a 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -4769,6 +4769,16 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (simplify (cmp:c (bit_and:c @0 @1) @0) (cmp (bit_and @0 (bit_not! @1)) { build_zero_cst (TREE_TYPE (@0)); })) + (simplify + (cmp:c (convert@3 (bit_and (convert@2 @0) INTEGER_CST@1)) (convert @0)) + (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) + && INTEGRAL_TYPE_P (TREE_TYPE (@2)) + && INTEGRAL_TYPE_P (TREE_TYPE (@3)) + && TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@0)) + && TYPE_PRECISION (TREE_TYPE (@3)) > TYPE_PRECISION (TREE_TYPE (@2)) + && !wi::neg_p (wi::to_wide (@1))) + (cmp (bit_and @0 (convert (bit_not @1))) + { build_zero_cst (TREE_TYPE (@0)); }))) /* (X | Y) == Y becomes (X & ~Y) == 0. */ (simplify |