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fold-const: Fix up ((1 << x) & y) != 0 folding for vectors [PR99225]

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This optimization was written purely with scalar integers in mind,
can work fine even with vectors, but we can't use build_int_cst but
need to use build_one_cst instead.

2021-02-24  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/99225
	* fold-const.c (fold_binary_loc) <case NE_EXPR>: In (x & (1 << y)) != 0
	to ((x >> y) & 1) != 0 simplifications use build_one_cst instead of
	build_int_cst (..., 1).  Formatting fixes.

	* gcc.c-torture/compile/pr99225.c: New test.
This commit is contained in:
Jakub Jelinek 2021-02-24 12:10:25 +01:00
parent 5296bd57d0
commit 6e646abbe0
2 changed files with 39 additions and 8 deletions
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16
gcc/fold-const.c
View File

@ -12044,23 +12044,23 @@ fold_binary_loc (location_t loc, enum tree_code code, tree type,
&& integer_onep (TREE_OPERAND (arg00, 0))) && integer_onep (TREE_OPERAND (arg00, 0)))
{ {
tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00), tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
arg01, TREE_OPERAND (arg00, 1)); arg01, TREE_OPERAND (arg00, 1));
tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem, tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
build_int_cst (TREE_TYPE (arg0), 1)); build_one_cst (TREE_TYPE (arg0)));
return fold_build2_loc (loc, code, type, return fold_build2_loc (loc, code, type,
fold_convert_loc (loc, TREE_TYPE (arg1), tem), fold_convert_loc (loc, TREE_TYPE (arg1),
arg1); tem), arg1);
} }
else if (TREE_CODE (arg01) == LSHIFT_EXPR else if (TREE_CODE (arg01) == LSHIFT_EXPR
&& integer_onep (TREE_OPERAND (arg01, 0))) && integer_onep (TREE_OPERAND (arg01, 0)))
{ {
tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01), tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
arg00, TREE_OPERAND (arg01, 1)); arg00, TREE_OPERAND (arg01, 1));
tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem, tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
build_int_cst (TREE_TYPE (arg0), 1)); build_one_cst (TREE_TYPE (arg0)));
return fold_build2_loc (loc, code, type, return fold_build2_loc (loc, code, type,
fold_convert_loc (loc, TREE_TYPE (arg1), tem), fold_convert_loc (loc, TREE_TYPE (arg1),
arg1); tem), arg1);
} }
} }

31
gcc/testsuite/gcc.c-torture/compile/pr99225.c Normal file
View File

@ -0,0 +1,31 @@
/* PR tree-optimization/99225 */
typedef int V __attribute__((vector_size (4 * sizeof (int))));
void
foo (V *x)
{
x[2] = (x[0] & (1 << x[1])) != 0;
}
void
bar (V *x)
{
x[2] = ((1 << x[1]) & x[0]) != 0;
}
void
baz (V *x)
{
V a = 1 << x[1];
V b = a & x[0];
x[2] = b != 0;
}
void
qux (V *x)
{
V a = 1 << x[1];
V b = x[0] & a;
x[2] = b != 0;
}