[PATCH] Fix PR tree-optimization/71179

[Kugan Vivekanandarajah]

Hi,

We don’t allow vector type for integer. Likewise I am also disallowing
the floating point vector type in transforming repeated addition to
multiplication.

This can be relaxed. I will send a separate patch to allow integer and
floating point vectorization later.

Bootstrapped and regression tested on x86-64-linux-gnu with no new regressions.

Is this OK for trunk?

Thanks,
Kugan

gcc/testsuite/ChangeLog:

2016-05-20  Kugan Vivekanandarajah  <kugan.vivekanandara...@linaro.org>

    * gcc.dg/tree-ssa/pr71179.c: New test.

gcc/ChangeLog:

2016-05-20  Kugan Vivekanandarajah  <kugan.vivekanandara...@linaro.org>

    * tree-ssa-reassoc.c (transform_add_to_multiply): Disallow float
VECTOR type.

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr71179.c 
b/gcc/testsuite/gcc.dg/tree-ssa/pr71179.c
index e69de29..885c643 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/pr71179.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr71179.c
@@ -0,0 +1,10 @@
+
+/* { dg-do compile } */
+/* { dg-options "-O3 -ffast-math" } */
+
+typedef float __m128 __attribute__ ((__vector_size__ (16), __may_alias__));
+
+__m128 foo (__m128 a)
+{
+  return a + a;
+}
diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c
index 3b5f36b..0c25a8c 100644
--- a/gcc/tree-ssa-reassoc.c
+++ b/gcc/tree-ssa-reassoc.c
@@ -1769,7 +1769,8 @@ transform_add_to_multiply (gimple *stmt, 
vec<operand_entry *> *ops)
   bool changed = false;
 
   if (!INTEGRAL_TYPE_P (TREE_TYPE ((*ops)[0]->op))
-      && !flag_unsafe_math_optimizations)
+      && (!SCALAR_FLOAT_TYPE_P (TREE_TYPE ((*ops)[0]->op))
+         || !flag_unsafe_math_optimizations))
     return false;
 
   /* Look for repeated operands.  */