tree-optimization/105250 - adjust fold_convertible_p PR105140 fix

The following reverts the original PR105140 fix and goes for instead
applying the additional fold_convert constraint for VECTOR_TYPE
conversions also to fold_convertible_p.  I did not try sanitizing
all of this at this point.

2022-04-13  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/105250
	* fold-const.cc (fold_convertible_p): Revert
	r12-7979-geaaf77dd85c333, instead check for size equality
	of the vector types involved.

	* gcc.dg/pr105250.c: New testcase.

diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 7226bc5..a57ad07 100644 (file)
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -2379,13 +2379,12 @@ build_zero_vector (tree type)
   return build_vector_from_val (type, t);
 }
 
-/* Returns true, if ARG, an operand or a type, is convertible to TYPE
-   using a NOP_EXPR.  */
+/* Returns true, if ARG is convertible to TYPE using a NOP_EXPR.  */
 
 bool
 fold_convertible_p (const_tree type, const_tree arg)
 {
-  const_tree orig = TYPE_P (arg) ? arg : TREE_TYPE (arg);
+  const_tree orig = TREE_TYPE (arg);
 
   if (type == orig)
     return true;
@@ -2417,7 +2416,7 @@ fold_convertible_p (const_tree type, const_tree arg)
       return (VECTOR_TYPE_P (orig)
              && known_eq (TYPE_VECTOR_SUBPARTS (type),
                           TYPE_VECTOR_SUBPARTS (orig))
-             && fold_convertible_p (TREE_TYPE (type), TREE_TYPE (orig)));
+             && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
 
     default:
       return false;

diff --git a/gcc/testsuite/gcc.dg/pr105250.c b/gcc/testsuite/gcc.dg/pr105250.c
new file mode 100644 (file)
index 0000000..665dd95
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr105250.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-w -Wno-psabi -O2" } */
+
+typedef int __attribute__((__vector_size__(4))) T;
+typedef int __attribute__((__vector_size__(8))) U;
+typedef int __attribute__((__vector_size__(16))) V;
+typedef int __attribute__((__vector_size__(32))) W;
+typedef _Float32 __attribute__((__vector_size__(16))) F;
+typedef _Float64 __attribute__((__vector_size__(32))) G;
+void foo();
+
+foo(int, int, int, int, U, U, V, V, W, W, int,
+     T, int, U, U, V, V, W, W, T,
+     T, int, U, U, V, V, W, W, T,
+     T, int, W, W, T, T, int, int, int,
+     int, int, int, W, int, int, int, int, int, int,
+     V, W, T, int, int, U, F, int, int, int,
+     int, int, int, G)
+{
+  foo(0, 0, 0, 0, (U){}, (U){}, (V){}, (V){}, (W){},
+       (W){}, 2, (T){}, 0, 0, 0, 0, (U){}, (U){},
+       (V){}, (V){}, (W){}, (W){}, (T){},
+       (T){}, 0, 0, 0, 0, (U){}, (U){}, (V){},
+       (V){}, (W){}, (W){}, (T){}, (T){}, 0, 0, 0,
+       0, 0, 0, (T){},
+       (T){}, (W){},
+       (W){}, (T){}, (T){}, 0, 0, 0, 0, 0, 0, (W){},
+       (V){}, (W){}, (T){}, 0, 0, (U){}, (F){});
+}