Add new FMA test case

From-SVN: r167312

gcc/testsuite/ChangeLog

+2010-11-30  Michael Meissner  <meissner@linux.vnet.ibm.com>
+
+	* gcc.target/powerpc/ppc-fma-7.c: New file, test that (a*b)+c and
+	(a*b)-c generates two fma instructions, instead of separate
+	multiply, add, and subtract.
+
 2010-11-30  Tobias Burnus  <burnus@net-b.de>
 
 	* gfortran.dg/realloc_on_assign_2.f03 (invima): Assign

gcc/testsuite/gcc.target/powerpc/ppc-fma-7.c

+/* { dg-do compile { target { powerpc*-*-* } } } */
+/* { dg-skip-if "" { powerpc*-*-darwin* } { "*" } { "" } } */
+/* { dg-require-effective-target powerpc_altivec_ok } */
+/* { dg-options "-O3 -ftree-vectorize -mcpu=power6 -ffast-math" } */
+/* { dg-final { scan-assembler-times "fmadd" 1 } } */
+/* { dg-final { scan-assembler-times "fmsub " 1 } } */
+/* { dg-final { scan-assembler-not "fmul" } } */
+/* { dg-final { scan-assembler-not "fadd " } } */
+
+/* Check whether the common FFT idiom (a*b)+c and (a*b)-c generates two fma
+   instructions, instead of a multiply, add, and subtract.  */
+
+void
+fft (double *result, double a, double b, double c)
+{
+  result[0] = (a*b) + c;
+  result[1] = (a*b) - c;
+}