mirror/gcc
1
0
Fork 0
mirror of https://github.com/gcc-mirror/gcc.git synced 2024-11-21 13:40:47 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

match: Add support for a ^ CST to bitwise_inverted_equal_p [PR115224]

Browse Source 
While looking into something else, I noticed that `a ^ CST` needed to be
special casing to bitwise_inverted_equal_p as it would simplify to `a ^ ~CST`
for the bitwise not.

Bootstrapped and tested on x86_64-linux-gnu with no regressions.

	PR tree-optimization/115224

gcc/ChangeLog:

	* generic-match-head.cc (bitwise_inverted_equal_p): Add `a ^ CST`
	case.
	* gimple-match-head.cc (gimple_bit_xor_cst): New declaration.
	(gimple_bitwise_inverted_equal_p): Add `a ^ CST` case.
	* match.pd (bit_xor_cst): New match.
	(maybe_bit_not): Add bit_xor_cst case.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/bitops-8.c: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
This commit is contained in:
Andrew Pinski 2024-05-26 17:38:37 -07:00
parent 0a9154d154
commit 547143df5a
4 changed files with 42 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
gcc/generic-match-head.cc
View File

@ -158,6 +158,16 @@ bitwise_inverted_equal_p (tree expr1, tree expr2, bool &wascmp)
if (TREE_CODE (expr2) == BIT_NOT_EXPR
&& bitwise_equal_p (expr1, TREE_OPERAND (expr2, 0)))
return true;
/* `X ^ CST` and `X ^ ~CST` match for ~. */
if (TREE_CODE (expr1) == BIT_XOR_EXPR && TREE_CODE (expr2) == BIT_XOR_EXPR
&& bitwise_equal_p (TREE_OPERAND (expr1, 0), TREE_OPERAND (expr2, 0)))
{
tree cst1 = uniform_integer_cst_p (TREE_OPERAND (expr1, 1));
tree cst2 = uniform_integer_cst_p (TREE_OPERAND (expr2, 1));
if (cst1 && cst2 && wi::to_wide (cst1) == ~wi::to_wide (cst2))
return true;
}
if (COMPARISON_CLASS_P (expr1)
&& COMPARISON_CLASS_P (expr2))
{

13
gcc/gimple-match-head.cc
View File

@ -283,6 +283,7 @@ gimple_bitwise_equal_p (tree expr1, tree expr2, tree (*valueize) (tree))
bool gimple_bit_not_with_nop (tree, tree *, tree (*) (tree));
bool gimple_maybe_cmp (tree, tree *, tree (*) (tree));
bool gimple_bit_xor_cst (tree, tree *, tree (*) (tree));
/* Helper function for bitwise_inverted_equal_p macro. */
@ -301,6 +302,18 @@ gimple_bitwise_inverted_equal_p (tree expr1, tree expr2, bool &wascmp, tree (*va
if (operand_equal_p (expr1, expr2, 0))
return false;
tree xor1[2];
tree xor2[2];
/* `X ^ CST` and `X ^ ~CST` match for ~. */
if (gimple_bit_xor_cst (expr1, xor1, valueize)
&& gimple_bit_xor_cst (expr2, xor2, valueize))
{
if (operand_equal_p (xor1[0], xor2[0], 0)
&& (wi::to_wide (uniform_integer_cst_p (xor1[1]))
== ~wi::to_wide (uniform_integer_cst_p (xor2[1]))))
return true;
}
tree other;
/* Try if EXPR1 was defined as ~EXPR2. */
if (gimple_bit_not_with_nop (expr1, &other, valueize))

4
gcc/match.pd
View File

@ -174,6 +174,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(match (bit_not_with_nop @0)
(convert (bit_not @0))
(if (tree_nop_conversion_p (type, TREE_TYPE (@0)))))
(match (bit_xor_cst @0 @1)
(bit_xor @0 uniform_integer_cst_p@1))
(for cmp (tcc_comparison)
(match (maybe_cmp @0)
(cmp@0 @1 @2))
@ -195,6 +197,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(INTEGER_CST@0))
(match (maybe_bit_not @0)
(maybe_cmp@0 @1))
(match (maybe_bit_not @0)
(bit_xor_cst@0 @1 @2))
/* Transform likes of (char) ABS_EXPR <(int) x> into (char) ABSU_EXPR <x>
ABSU_EXPR returns unsigned absolute value of the operand and the operand

15
gcc/testsuite/gcc.dg/tree-ssa/bitops-8.c Normal file
View File

@ -0,0 +1,15 @@
/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-optimized-raw" } */
/* PR tree-optimization/115224 */
int f1(int a, int b)
{
a = a ^ 1;
int c = ~a;
return c | (a ^ b);
// ~((a ^ 1) & b) or (a ^ -2) | ~b
}
/* { dg-final { scan-tree-dump-times "bit_xor_expr, " 1 "optimized" } } */
/* { dg-final { scan-tree-dump-times "bit_ior_expr, " 1 "optimized" } } */
/* { dg-final { scan-tree-dump-times "bit_not_expr, " 1 "optimized" } } */