Index: match.pd
===================================================================
--- match.pd	(revision 249626)
+++ match.pd	(working copy)
@@ -155,6 +155,58 @@
            || !COMPLEX_FLOAT_TYPE_P (type)))
    (negate @0)))
 
+(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@1 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 @1 (outp @0)))
+    (if (types_match (type, double_type_node))
+     (BUILT_IN_COPYSIGN @1 (outp @0)))
+    (if (types_match (type, long_double_type_node))
+     (BUILT_IN_COPYSIGNL @1 (outp @0))))))
+ /* 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@1)
+  (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 @1 (outn @0)))
+    (if (types_match (type, double_type_node))
+     (BUILT_IN_COPYSIGN @1 (outn @0)))
+    (if (types_match (type, long_double_type_node))
+     (BUILT_IN_COPYSIGNL @1 (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)))
+
+/* 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 (CST, X) into copysign (ABS(CST), X). */
+(simplify
+ (COPYSIGN REAL_CST@0 @1)
+ (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@0)))
+  (COPYSIGN (negate @0) @1)))
+
 /* X * 1, X / 1 -> X.  */
 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
   (simplify
Index: testsuite/gcc.dg/tree-ssa/copy-sign-1.c
===================================================================
--- testsuite/gcc.dg/tree-ssa/copy-sign-1.c	(nonexistent)
+++ testsuite/gcc.dg/tree-ssa/copy-sign-1.c	(working copy)
@@ -0,0 +1,35 @@
+/* { dg-options "-O2 -ffast-math -fdump-tree-gimple" } */
+/* { dg-do compile } */
+float f(float x)
+{
+  return (x > 0.f ? -1.f : 1.f);
+}
+float f1(float x)
+{
+  return (x > 0.f ? 1.f : -1.f);
+}
+float g(float x)
+{
+  return (x >= 0.f ? -1.f : 1.f);
+}
+float g1(float x)
+{
+  return (x >= 0.f ? 1.f : -1.f);
+}
+float h(float x)
+{
+  return (x < 0.f ? -1.f : 1.f);
+}
+float h1(float x)
+{
+  return (x < 0.f ? 1.f : -1.f);
+}
+float i(float x)
+{
+  return (x <= 0.f ? -1.f : 1.f);
+}
+float i1(float x)
+{
+  return (x <= 0.f ? 1.f : -1.f);
+}
+/* { dg-final { scan-tree-dump-times "copysign" 8 "gimple"} } */
Index: testsuite/gcc.dg/tree-ssa/copy-sign-2.c
===================================================================
--- testsuite/gcc.dg/tree-ssa/copy-sign-2.c	(nonexistent)
+++ testsuite/gcc.dg/tree-ssa/copy-sign-2.c	(working copy)
@@ -0,0 +1,13 @@
+/* { dg-options "-O2 -ffast-math -fdump-tree-optimized" } */
+/* { dg-do compile } */
+float f(float x)
+{
+  float t = __builtin_copysignf (1.0f, x);
+  return x * t;
+}
+float f1(float x)
+{
+  float t = __builtin_copysignf (1.0f, -x);
+  return x * t;
+}
+/* { dg-final { scan-tree-dump-times "ABS" 2 "optimized"} } */
Index: testsuite/gcc.dg/tree-ssa/mult-abs-2.c
===================================================================
--- testsuite/gcc.dg/tree-ssa/mult-abs-2.c	(nonexistent)
+++ testsuite/gcc.dg/tree-ssa/mult-abs-2.c	(working copy)
@@ -0,0 +1,35 @@
+/* { dg-options "-O2 -ffast-math -fdump-tree-gimple" } */
+/* { dg-do compile } */
+float f(float x)
+{
+  return x * (x > 0.f ? -1.f : 1.f);
+}
+float f1(float x)
+{
+  return x * (x > 0.f ? 1.f : -1.f);
+}
+float g(float x)
+{
+  return x * (x >= 0.f ? -1.f : 1.f);
+}
+float g1(float x)
+{
+  return x * (x >= 0.f ? 1.f : -1.f);
+}
+float h(float x)
+{
+  return x * (x < 0.f ? -1.f : 1.f);
+}
+float h1(float x)
+{
+  return x * (x < 0.f ? 1.f : -1.f);
+}
+float i(float x)
+{
+  return x * (x <= 0.f ? -1.f : 1.f);
+}
+float i1(float x)
+{
+  return x * (x <= 0.f ? 1.f : -1.f);
+}
+/* { dg-final { scan-tree-dump-times "ABS" 8 "gimple"} } */