re PR middle-end/72747 (powerpc: wrong code generated for vec_splats in cascading assignment)

gcc:
2016-10-26  Will Schmidt <will_schmidt@vnet.ibm.com>

        PR middle-end/72747
        * gimplify.c (gimplify_init_constructor): Move emit of constructor
        assignment to earlier in the if/else logic.

testsuite:
2016-10-26  Will Schmidt <will_schmidt@vnet.ibm.com>

        PR middle-end/72747
        * c-c++-common/pr72747-1.c: New test.
        * c-c++-common/pr72747-2.c: Likewise.

From-SVN: r241647

gcc/ChangeLog

+2016-10-28  Will Schmidt <will_schmidt@vnet.ibm.com>
+
+	PR middle-end/72747
+	* gimplify.c (gimplify_init_constructor): Move emit of constructor
+	assignment to earlier in the if/else logic.
+
 2016-10-28  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/78128

gcc/gimplify.c

@@ -4730,24 +4730,23 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
 
   if (ret == GS_ERROR)
     return GS_ERROR;
-  else if (want_value)
+  /* If we have gimplified both sides of the initializer but have
+     not emitted an assignment, do so now.  */
+  if (*expr_p)
+    {
+      tree lhs = TREE_OPERAND (*expr_p, 0);
+      tree rhs = TREE_OPERAND (*expr_p, 1);
+      gassign *init = gimple_build_assign (lhs, rhs);
+      gimplify_seq_add_stmt (pre_p, init);
+    }
+  if (want_value)
     {
       *expr_p = object;
       return GS_OK;
     }
   else
     {
-      /* If we have gimplified both sides of the initializer but have
-	 not emitted an assignment, do so now.  */
-      if (*expr_p)
-	{
-	  tree lhs = TREE_OPERAND (*expr_p, 0);
-	  tree rhs = TREE_OPERAND (*expr_p, 1);
-	  gassign *init = gimple_build_assign (lhs, rhs);
-	  gimplify_seq_add_stmt (pre_p, init);
-	  *expr_p = NULL;
-	}
-
+      *expr_p = NULL;
       return GS_ALL_DONE;
     }
 }

gcc/testsuite/ChangeLog

+2016-10-26  Will Schmidt <will_schmidt@vnet.ibm.com>
+
+	PR middle-end/72747
+	* c-c++-common/pr72747-1.c: New test.
+	* c-c++-common/pr72747-2.c: Likewise.
+
 2016-10-28  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
 	* gcc.target/s390/oscbreak-1.c: New test.

gcc/testsuite/c-c++-common/pr72747-1.c

+/* { dg-do compile } */
+/* { dg-require-effective-target powerpc_altivec_ok } */
+/* { dg-options "-maltivec -fdump-tree-gimple" } */
+
+/* PR 72747: Test that cascaded definition is happening for constant vectors. */
+
+#include <altivec.h>
+
+int main (int argc, char *argv[])
+{
+	__vector int v1,v2;
+	v1 = v2 = vec_splats ((int) 42);
+	return 0;
+}
+/* { dg-final { scan-tree-dump-times " v2 = { 42, 42, 42, 42 }" 1 "gimple" } } */
+

gcc/testsuite/c-c++-common/pr72747-2.c

+/* { dg-do compile } */
+/* { dg-require-effective-target powerpc_altivec_ok } */
+/* { dg-options "-c -maltivec -fdump-tree-gimple" } */
+
+/* PR 72747: test that cascaded definition is happening for non constants. */
+
+void foo ()
+{
+  extern int i;
+  __vector int v,w;
+    v = w = (vector int) { i };
+}
+
+int main (int argc, char *argv[])
+{
+  return 0;
+}
+/* { dg-final { scan-tree-dump-times " w = {i.0_1}" 1 "gimple" } } */