Hi!
My PR85077
+ if (VECTOR_TYPE_P (TREE_TYPE (x)))
+ x = fold (x);
cp_fold change apparently broke the following and similar testcases, if
split_nonconstant_init splits the initialization into a runtime part and
some CONSTRUCTOR, it clears TREE_READONLY on it, and constant_value_1
had code to avoid returning that CONSTRUCTOR as the value if not
DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P because that CONSTRUCTOR is only
part of the story. With the PR85077 change, such CONSTRUCTORs are turned
into VECTOR_CSTs by fold though and constant_value_1 then returns the wrong
thing.
Fixed thusly, bootstrapped/regtested on x86_64-linux, ok for trunk and
9.2/8.4?
2019-06-10 Jakub Jelinek <ja...@redhat.com>
PR c++/90810
* init.c (constant_value_1): Handle VECTOR_CST DECL_INITIAL for
!DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P decls like CONSTRUCTOR.
* g++.dg/ext/vector37.C: New test.
--- gcc/cp/init.c.jj 2019-05-23 12:57:16.624494279 +0200
+++ gcc/cp/init.c 2019-06-10 17:07:34.779366457 +0200
@@ -2339,8 +2339,11 @@ constant_value_1 (tree decl, bool strict
|| TREE_CODE (init) == STRING_CST)))
break;
/* Don't return a CONSTRUCTOR for a variable with partial run-time
- initialization, since it doesn't represent the entire value. */
- if (TREE_CODE (init) == CONSTRUCTOR
+ initialization, since it doesn't represent the entire value.
+ Similarly for VECTOR_CSTs created by cp_folding those
+ CONSTRUCTORs. */
+ if ((TREE_CODE (init) == CONSTRUCTOR
+ || TREE_CODE (init) == VECTOR_CST)
&& !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
break;
/* If the variable has a dynamic initializer, don't use its
--- gcc/testsuite/g++.dg/ext/vector37.C.jj 2019-06-10 17:12:29.092801825
+0200
+++ gcc/testsuite/g++.dg/ext/vector37.C 2019-06-10 17:11:35.641630817 +0200
@@ -0,0 +1,29 @@
+// PR c++/90810
+// { dg-do run }
+
+void
+foo (float x, float y)
+{
+ typedef float __attribute__ ((__vector_size__ (4 * sizeof (float)),
__may_alias__)) V;
+ const V a = { x, x, x, x }, b = { y, y, y, y };
+ const V c = a / b;
+ if (c[0] != 6.0f || c[1] != 6.0f || c[2] != 6.0f || c[3] != 6.0f)
+ __builtin_abort ();
+}
+
+void
+bar (float y)
+{
+ typedef float __attribute__ ((__vector_size__ (4 * sizeof (float)),
__may_alias__)) V;
+ const V a = { 7.0f, 8.0f, 9.0f, 10.0f }, b = { 1.0f, 2.0f, 3.0f, y };
+ const V c = a / b;
+ if (c[0] != 7.0f || c[1] != 4.0f || c[2] != 3.0f || c[3] != 5.0f)
+ __builtin_abort ();
+}
+
+int
+main ()
+{
+ foo (12.0f, 2.0f);
+ bar (2.0f);
+}
Jakub
