* real.h (REAL_VALUES_IDENTICAL): New macro.
* expr.c (is_zeros_p): Don't consider -0.0 to be all zeros.
* fold-const.c (operand_equal_p): Don't consider -0.0 to be
identical to 0.0.
* tree.c (simple_cst_equal): Don't consider -0.0 to have the
same tree structure as 0.0.
* varasm.c (immed_real_const_1): Use new REAL_VALUES_IDENTICAL
macro instead of doing it by hand.
From-SVN: r16472
+1997-11-13 Paul Eggert <eggert@twinsun.com>
+
+ Fix some confusion with IEEE minus zero.
+
+ * real.h (REAL_VALUES_IDENTICAL): New macro.
+
+ * expr.c (is_zeros_p): Don't consider -0.0 to be all zeros.
+ * fold-const.c (operand_equal_p): Don't consider -0.0 to be
+ identical to 0.0.
+ * tree.c (simple_cst_equal): Don't consider -0.0 to have the
+ same tree structure as 0.0.
+
+ * varasm.c (immed_real_const_1): Use new REAL_VALUES_IDENTICAL
+ macro instead of doing it by hand.
+
Thu Nov 13 16:56:14 1997 Jeffrey A Law (law@cygnus.com)
* v850/lib1funcs.asm: Minor whitespace changes.
is_zeros_p (TREE_REALPART (exp)) && is_zeros_p (TREE_IMAGPART (exp));
case REAL_CST:
- return REAL_VALUES_EQUAL (TREE_REAL_CST (exp), dconst0);
+ return REAL_VALUES_IDENTICAL (TREE_REAL_CST (exp), dconst0);
case CONSTRUCTOR:
if (TREE_TYPE (exp) && TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
case REAL_CST:
return (! TREE_CONSTANT_OVERFLOW (arg0)
&& ! TREE_CONSTANT_OVERFLOW (arg1)
- && REAL_VALUES_EQUAL (TREE_REAL_CST (arg0),
- TREE_REAL_CST (arg1)));
+ && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
+ TREE_REAL_CST (arg1)));
case COMPLEX_CST:
return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
#define REAL_VALUE_TO_TARGET_LONG_DOUBLE(a, b) REAL_VALUE_TO_TARGET_DOUBLE (a, b)
#endif
+/* Compare two floating-point objects for bitwise identity.
+ This is not the same as comparing for equality on IEEE hosts:
+ -0.0 equals 0.0 but they are not identical, and conversely
+ two NaNs might be identical but they cannot be equal. */
+#define REAL_VALUES_IDENTICAL(x, y) \
+ (!bcmp ((char *) &(x), (char *) &(y), sizeof (REAL_VALUE_TYPE)))
+
/* Compare two floating-point values for equality. */
#ifndef REAL_VALUES_EQUAL
#define REAL_VALUES_EQUAL(x, y) ((x) == (y))
&& TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
case REAL_CST:
- return REAL_VALUES_EQUAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
+ return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
case STRING_CST:
return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
/* Detect special cases. */
- /* Avoid REAL_VALUES_EQUAL here in order to distinguish minus zero. */
- if (!bcmp ((char *) &dconst0, (char *) &d, sizeof d))
+ if (REAL_VALUES_IDENTICAL (dconst0, d))
return CONST0_RTX (mode);
/* Check for NaN first, because some ports (specifically the i386) do not
emit correct ieee-fp code by default, and thus will generate a core