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Fix PR110726: a | (a == b) can sometimes produce wrong code

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So I had missed/forgot that EQ_EXPR could have an non boolean
type for generic when I implemented r14-2556-g0407ae8a7732d9.
This patch adds check for one bit precision intergal type
which fixes the problem.

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

	PR tree-optimization/110726

gcc/ChangeLog:

	* match.pd ((a|b)&(a==b),a|(a==b),(a&b)|(a==b)):
	Add checks to make sure the type was one bit precision
	intergal type.

gcc/testsuite/ChangeLog:

	* gcc.c-torture/execute/bitops-1.c: New test.
This commit is contained in:
Andrew Pinski 2023-07-18 21:11:46 +00:00
parent 344f413220
commit bf20b770d9
2 changed files with 42 additions and 3 deletions
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12
gcc/match.pd
View file

@ -1229,7 +1229,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* (a | b) & (a == b) --> a & b (boolean version of the above). */
(simplify
(bit_and:c (bit_ior @0 @1) (nop_convert? (eq:c @0 @1)))
(bit_and @0 @1))
(if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
&& TYPE_PRECISION (TREE_TYPE (@0)) == 1)
(bit_and @0 @1)))
/* a | ~(a ^ b) --> a | ~b */
(simplify
@ -1239,7 +1241,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* a | (a == b) --> a | (b^1) (boolean version of the above). */
(simplify
(bit_ior:c @0 (nop_convert? (eq:c @0 @1)))
(bit_ior @0 (bit_xor @1 { build_one_cst (type); })))
(if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
&& TYPE_PRECISION (TREE_TYPE (@0)) == 1)
(bit_ior @0 (bit_xor @1 { build_one_cst (type); }))))
/* (a | b) | (a &^ b) --> a | b */
(for op (bit_and bit_xor)
@ -1255,7 +1259,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* (a & b) | (a == b) --> a == b */
(simplify
(bit_ior:c (bit_and:c @0 @1) (nop_convert?@2 (eq @0 @1)))
@2)
(if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
&& TYPE_PRECISION (TREE_TYPE (@0)) == 1)
@2))
/* ~(~a & b) --> a | ~b */
(simplify

33
gcc/testsuite/gcc.c-torture/execute/bitops-1.c Normal file
View file

@ -0,0 +1,33 @@
/* PR tree-optimization/110726 */
#define DECLS(n,VOL) \
__attribute__((noinline,noclone)) \
int h##n(VOL int A, VOL int B){ \
return (A | B) & (A == B); \
} \
__attribute__((noinline,noclone)) \
int i##n(VOL int A, VOL int B){ \
return A | (A == B); \
} \
__attribute__((noinline,noclone)) \
int k##n(VOL int A, VOL int B){ \
return (A & B) | (A == B); \
} \
DECLS(0,)
DECLS(1,volatile)
int values[] = { 0, 1, 2, 3, -1, -2, -3, 0x10080 };
int numvalues = sizeof(values)/sizeof(values[0]);
int main(){
for(int A = 0; A < numvalues; A++)
for(int B = 0; B < numvalues; B++)
{
int a = values[A];
int b = values[B];
if (h0 (a, b) != h1 (a, b)) __builtin_abort();
if (i0 (a, b) != i1 (a, b)) __builtin_abort();
if (k0 (a, b) != k1 (a, b)) __builtin_abort();
}
}