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| author | Marc Glisse <marc.glisse@inria.fr> | 2016-05-17 19:57:27 +0200 |
|---|---|---|
| committer | Marc Glisse <glisse@gcc.gnu.org> | 2016-05-17 17:57:27 +0000 |
| commit | c7986356a1ca8e8e671af74e9e7b76d14238bd5f (patch) | |
| tree | 7114d3925db69527c7a16eef0f554a9b15efb76c | |
| parent | d982c5b7b73b9bed5d63d614dc2ae4f17d49eb74 (diff) | |
| download | gcc-c7986356a1ca8e8e671af74e9e7b76d14238bd5f.zip gcc-c7986356a1ca8e8e671af74e9e7b76d14238bd5f.tar.gz gcc-c7986356a1ca8e8e671af74e9e7b76d14238bd5f.tar.bz2 | |
x & C -> x if we know that x & ~C == 0
2016-05-17 Marc Glisse <marc.glisse@inria.fr>
gcc/
* match.pd (X & C): New transformation.
gcc/testsuite/
* gcc.dg/tree-ssa/and-1.c: New testcase.
From-SVN: r236338
| -rw-r--r-- | gcc/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/match.pd | 9 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/and-1.c | 11 |
4 files changed, 28 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9ec5a9e..7f72227 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,9 @@ 2016-05-17 Marc Glisse <marc.glisse@inria.fr> + * match.pd (X & C): New transformation. + +2016-05-17 Marc Glisse <marc.glisse@inria.fr> + * match.pd (~X & Y): New transformation. 2016-05-17 Marc Glisse <marc.glisse@inria.fr> diff --git a/gcc/match.pd b/gcc/match.pd index acc41be..db8e39c 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -563,6 +563,15 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (bitop @0 @0) (non_lvalue @0))) +/* x & C -> x if we know that x & ~C == 0. */ +#if GIMPLE +(simplify + (bit_and SSA_NAME@0 INTEGER_CST@1) + (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) + && (get_nonzero_bits (@0) & wi::bit_not (@1)) == 0) + @0)) +#endif + /* x + (x & 1) -> (x + 1) & ~1 */ (simplify (plus:c @0 (bit_and:s @0 integer_onep@1)) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 61b6a22..0e648e5 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,9 @@ 2016-05-17 Marc Glisse <marc.glisse@inria.fr> + * gcc.dg/tree-ssa/and-1.c: New testcase. + +2016-05-17 Marc Glisse <marc.glisse@inria.fr> + * gcc.dg/tree-ssa/pr69270.c: Adjust. * gcc.dg/tree-ssa/andnot-1.c: New testcase. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/and-1.c b/gcc/testsuite/gcc.dg/tree-ssa/and-1.c new file mode 100644 index 0000000..276c2b9 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/and-1.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-optimized-raw" } */ + +int f(int in) { + in = in | 3; + in = in ^ 1; + in = (in & ~(unsigned long)1); + return in; +} + +/* { dg-final { scan-tree-dump-not "bit_and_expr" "optimized" } } */ |