+(for cmp (gt ge lt le)
+ outp (convert convert negate negate)
+ outn (negate negate convert convert)
+ /* Transform (X > 0.0 ? 1.0 : -1.0) into copysign(1, X). */
+ /* Transform (X >= 0.0 ? 1.0 : -1.0) into copysign(1, X). */
+ /* Transform (X < 0.0 ? 1.0 : -1.0) into copysign(1,-X). */
+ /* Transform (X <= 0.0 ? 1.0 : -1.0) into copysign(1,-X). */
+ (simplify
+ (cond (cmp @0 real_zerop) real_onep real_minus_onep)
+ (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type)
+ && types_match (type, TREE_TYPE (@0)))
+ (switch
+ (if (types_match (type, float_type_node))
+ (BUILT_IN_COPYSIGNF { build_one_cst (type); } (outp @0)))
+ (if (types_match (type, double_type_node))
+ (BUILT_IN_COPYSIGN { build_one_cst (type); } (outp @0)))
+ (if (types_match (type, long_double_type_node))
+ (BUILT_IN_COPYSIGNL { build_one_cst (type); } (outp @0))))))
There is already a 1.0 of the right type in the input, it would be easier
to reuse it in the output than build a new one.
Non-generic builtins like copysign are such a pain... We also end up
missing the 128-bit case that way (pre-existing problem, not your patch).
We seem to have a corresponding internal function, but apparently it is
not used until expansion (well, maybe during vectorization).
+ /* Transform (X > 0.0 ? -1.0 : 1.0) into copysign(1,-X). */
+ /* Transform (X >= 0.0 ? -1.0 : 1.0) into copysign(1,-X). */
+ /* Transform (X < 0.0 ? -1.0 : 1.0) into copysign(1,X). */
+ /* Transform (X <= 0.0 ? -1.0 : 1.0) into copysign(1,X). */
+ (simplify
+ (cond (cmp @0 real_zerop) real_minus_onep real_onep)
+ (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type)
+ && types_match (type, TREE_TYPE (@0)))
+ (switch
+ (if (types_match (type, float_type_node))
+ (BUILT_IN_COPYSIGNF { build_one_cst (type); } (outn @0)))
+ (if (types_match (type, double_type_node))
+ (BUILT_IN_COPYSIGN { build_one_cst (type); } (outn @0)))
+ (if (types_match (type, long_double_type_node))
+ (BUILT_IN_COPYSIGNL { build_one_cst (type); } (outn @0)))))))
+
+/* Transform X * copysign (1.0, X) into abs(X). */
+(simplify
+ (mult:c @0 (COPYSIGN real_onep @0))
+ (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type))
+ (abs @0)))
I would have expected it do to the right thing for signed zero and qNaN.
Can you describe a case where it would give the wrong result, or are the
conditions just conservative?
+/* Transform X * copysign (1.0, -X) into -abs(X). */
+(simplify
+ (mult:c @0 (COPYSIGN real_onep (negate @0)))
+ (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type))
+ (negate (abs @0))))
+
+/* Transform copysign (-1.0, X) into copysign (1.0, X). */
+(simplify
+ (COPYSIGN real_minus_onep @0)
+ (COPYSIGN { build_one_cst (type); } @0))
(simplify
(COPYSIGN REAL_CST@0 @1)
(if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@0)))
(COPYSIGN (negate @0) @1)))
? Or does that create trouble with sNaN and only the 1.0 case is worth
the trouble?
--
Marc Glisse
