simplify-rtx.c (simplify_binary_operation_1): Do not simplify IOR to a constant if one operand has side effects.

* simplify-rtx.c (simplify_binary_operation_1): Do not simplify
	IOR to a constant if one operand has side effects.

testsuite:
	* gcc.c-torture/execute/20120808-1.c: New test.

From-SVN: r190237
This commit is contained in:
Joseph Myers 2012-08-08 20:42:58 +01:00 committed by Joseph Myers
parent 215770ada8
commit e7160b278e
4 changed files with 51 additions and 2 deletions

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@ -1,3 +1,8 @@
2012-08-08 Joseph Myers <joseph@codesourcery.com>
* simplify-rtx.c (simplify_binary_operation_1): Do not simplify
IOR to a constant if one operand has side effects.
2012-08-08 Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
* builtins.c (expand_builtin_atomic_compare_exchange): Pass old

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@ -2420,7 +2420,9 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
case IOR:
if (trueop1 == CONST0_RTX (mode))
return op0;
if (INTEGRAL_MODE_P (mode) && trueop1 == CONSTM1_RTX (mode))
if (INTEGRAL_MODE_P (mode)
&& trueop1 == CONSTM1_RTX (mode)
&& !side_effects_p (op0))
return op1;
if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
return op0;
@ -2434,7 +2436,8 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
/* (ior A C) is C if all bits of A that might be nonzero are on in C. */
if (CONST_INT_P (op1)
&& HWI_COMPUTABLE_MODE_P (mode)
&& (nonzero_bits (op0, mode) & ~UINTVAL (op1)) == 0)
&& (nonzero_bits (op0, mode) & ~UINTVAL (op1)) == 0
&& !side_effects_p (op0))
return op1;
/* Canonicalize (X & C1) | C2. */

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@ -1,3 +1,7 @@
2012-08-08 Joseph Myers <joseph@codesourcery.com>
* gcc.c-torture/execute/20120808-1.c: New test.
2012-08-08 H.J. Lu <hongjiu.lu@intel.com>
PR rtl-optimization/54157

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@ -0,0 +1,37 @@
extern void exit (int);
extern void abort (void);
volatile int i;
unsigned char *volatile cp;
unsigned char d[32] = { 0 };
int
main (void)
{
unsigned char c[32] = { 0 };
unsigned char *p = d + i;
int j;
for (j = 0; j < 30; j++)
{
int x = 0xff;
int y = *++p;
switch (j)
{
case 1: x ^= 2; break;
case 2: x ^= 4; break;
case 25: x ^= 1; break;
default: break;
}
c[j] = y | x;
cp = p;
}
if (c[0] != 0xff
|| c[1] != 0xfd
|| c[2] != 0xfb
|| c[3] != 0xff
|| c[4] != 0xff
|| c[25] != 0xfe
|| cp != d + 30)
abort ();
exit (0);
}