PR91166 - Unfolded ZIPs of constants

[Prathamesh Kulkarni]

Hi,
The attached patch tries to fix PR91166.
Does it look OK ?
Bootstrap+test in progress on aarch64-linux-gnu and x86_64-unknown-linux-gnu.

Thanks,
Prathamesh
-------------- next part --------------
2019-07-17  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>

	PR middle-end/91166
	* match.pd (vec_perm_expr(v, v, mask) -> v): New pattern.
	(define_predicates): Add entry for uniform_vector_p.

testsuite/
	* gcc.target/aarch64/sve/pr91166.c: New test.

diff --git a/gcc/match.pd b/gcc/match.pd
index 4a7aa0185d8..2ad98c28fd8 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -36,7 +36,8 @@ along with GCC; see the file COPYING3.  If not see
    integer_valued_real_p
    integer_pow2p
    uniform_integer_cst_p
-   HONOR_NANS)
+   HONOR_NANS
+   uniform_vector_p)
 
 /* Operator lists.  */
 (define_operator_list tcc_comparison
@@ -5568,3 +5569,12 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
          { bitsize_int (at * tree_to_uhwi (TYPE_SIZE (TREE_TYPE (type)))); })
        (if (changed)
         (vec_perm { op0; } { op1; } { op2; }))))))))))
+
+/* VEC_PERM_EXPR (v, v, mask) -> v where v contains same element.  */
+(simplify
+ (vec_perm (vec_duplicate@0 @1) @0 @2)
+ { @0; })
+
+(simplify
+ (vec_perm uniform_vector_p@0 @0 @1)
+ { @0; }) 
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/pr91166.c b/gcc/testsuite/gcc.target/aarch64/sve/pr91166.c
new file mode 100644
index 00000000000..42654be3b31
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/pr91166.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=armv8.2-a+sve -fdump-tree-optimized" } */
+
+void
+f1 (double x[][4]) 
+{
+  for (int i = 0; i < 4; ++i)
+    for (int j = 0; j < 4; ++j)
+      x[i][j] = 0;
+}
+
+void
+f2 (double x[][4], double y)
+{
+  for (int i = 0; i < 4; ++i)
+    for (int j = 0; j < 4; ++j)
+      x[i][j] = y;
+}
+
+/* { dg-final { scan-tree-dump-not "VEC_PERM_EXPR" "optimized"} } */