emit-rtl.c (dconstm2, dconsthalf): New real constants.

	* emit-rtl.c (dconstm2, dconsthalf): New real constants.
	(init_emit_once): Initialize dconstm2 and dconsthalf here.
	* real.h (dconstm2, dconsthalf): Add prototypes here.
	* real.c (real_sqrt): Use dconsthalf rather than local copy.
	* builtins.c (fold_builtin): When optimizing sqrt(exp(x)) as
	exp(x/2.0) remember to fold the division if possible.
	Fold sin(0.0) as 0.0, cos(0.0) as 1.0, pow(x,1.0) as x,
	pow(x,-1.0) as 1.0/x, pow(x,2.0) as x*x, pow(x,-2.0) as
	1.0/(x*x) and pow(x,0.5) as sqrt(x).

	* gcc.dg/builtins-3.c: Add new tests for sin and cos.
	* gcc.dg/builtins-7.c: New test case.
	* gcc.dg/builtins-8.c: New test case.

From-SVN: r65088

1 files changed, 39 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/builtins-7.c b/gcc/testsuite/gcc.dg/builtins-7.c
new file mode 100644
index 0000000..84c0e15
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/builtins-7.c
@@ -0,0 +1,39 @@
+/* Copyright (C) 2003  Free Software Foundation.
+
+   Verify that built-in math function constant folding of constant
+   arguments is correctly performed by the by the compiler.
+
+   Written by Roger Sayle, 30th March 2003.  */
+
+/* { dg-do link } */
+/* { dg-options "-O2 -ffast-math" } */
+
+extern void link_error(void);
+
+void test(double x)
+{
+  if (pow (x, 1.0) != x)
+    link_error ();
+}
+
+void testf(float x)
+{
+  if (powf (x, 1.0f) != x)
+    link_error ();
+}
+
+void testl(long double x)
+{
+  if (powl (x, 1.0l) != x)
+    link_error ();
+}
+
+int main()
+{
+  test (2.0);
+  testf (2.0f);
+  testl (2.0l);
+
+  return 0;
+}
+