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re PR tree-optimization/93118 (>>32<<32 is not always converted into &~0ffffffffull at the tree level)

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PR tree-optimization/93118
	* match.pd ((x >> c) << c -> x & (-1<<c)): Add nop_convert?.  Add new
	simplifier with two intermediate conversions.

	* gcc.dg/tree-ssa/pr93118.c: New test.

From-SVN: r279950
This commit is contained in:
Jakub Jelinek 2020-01-07 11:03:07 +01:00 committed by Jakub Jelinek
parent 5c4177c508
commit f26916c2ac
4 changed files with 75 additions and 2 deletions
gcc
ChangeLogmatch.pd
testsuite
ChangeLog
gcc.dg/tree-ssa
pr93118.c

6
gcc/ChangeLog

@ -1,3 +1,9 @@
2019-01-07 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/93118
* match.pd ((x >> c) << c -> x & (-1<<c)): Add nop_convert?. Add new
simplifier with two intermediate conversions.
2020-01-07 Martin Liska <mliska@suse.cz>
* params.opt: Add Optimization for various parameters.

21
gcc/match.pd

@ -2738,9 +2738,26 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* Optimize (x >> c) << c into x & (-1<<c). */
(simplify
(lshift (rshift @0 INTEGER_CST@1) @1)
(lshift (nop_convert? (rshift @0 INTEGER_CST@1)) @1)
(if (wi::ltu_p (wi::to_wide (@1), element_precision (type)))
(bit_and @0 (lshift { build_minus_one_cst (type); } @1))))
/* It doesn't matter if the right shift is arithmetic or logical. */
(bit_and (view_convert @0) (lshift { build_minus_one_cst (type); } @1))))
(simplify
(lshift (convert (convert@2 (rshift @0 INTEGER_CST@1))) @1)
(if (wi::ltu_p (wi::to_wide (@1), element_precision (type))
/* Allow intermediate conversion to integral type with whatever sign, as
long as the low TYPE_PRECISION (type)
- TYPE_PRECISION (TREE_TYPE (@2)) bits are preserved. */
&& INTEGRAL_TYPE_P (type)
&& INTEGRAL_TYPE_P (TREE_TYPE (@2))
&& INTEGRAL_TYPE_P (TREE_TYPE (@0))
&& TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0))
&& (TYPE_PRECISION (TREE_TYPE (@2)) >= TYPE_PRECISION (type)
|| wi::geu_p (wi::to_wide (@1),
TYPE_PRECISION (type)
- TYPE_PRECISION (TREE_TYPE (@2)))))
(bit_and (convert @0) (lshift { build_minus_one_cst (type); } @1))))
/* Optimize (x << c) >> c into x & ((unsigned)-1 >> c) for unsigned
types. */

5
gcc/testsuite/ChangeLog

@ -1,3 +1,8 @@
2019-01-07 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/93118
* gcc.dg/tree-ssa/pr93118.c: New test.
2020-01-07 Martin Liska <mliska@suse.cz>
PR tree-optimization/92860

45
gcc/testsuite/gcc.dg/tree-ssa/pr93118.c Normal file

@ -0,0 +1,45 @@
/* PR tree-optimization/93118 */
/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-optimized" } */
/* { dg-final { scan-tree-dump-not ">>" "optimized" } } */
/* { dg-final { scan-tree-dump-not "<<" "optimized" } } */
#if __SIZEOF_LONG_LONG__ == 8 && __SIZEOF_INT__ == 4 && __CHAR_BIT__ == 8
unsigned long long
foo (unsigned long long a)
{
unsigned long long b = a >> 32;
int c = b;
unsigned long long d = c;
return d << 32;
}
unsigned long long
bar (unsigned long long a)
{
unsigned long long b = a >> 32;
unsigned c = b;
unsigned long long d = c;
return d << 32;
}
unsigned long long
baz (long long a)
{
long long b = a >> 32;
unsigned long long c = b;
return c << 32;
}
typedef unsigned V __attribute__((vector_size (2 * sizeof (int))));
typedef int W __attribute__((vector_size (2 * sizeof (int))));
void
quux (W *w, V *v)
{
W a = (W) (*v >> 16);
*w = a << 16;
}
#else
int i;
#endif