When the call to useless_type_conversion_p was removed for the pointer sub-case
in the GIMPLE_UNARY_RHS case, it was replaced with a check on TYPE_ADDR_SPACE.
This isn't sufficient to guarantee that the value is preserved when pointer can
have different modes like on s390x or VMS, and useless_type_conversion_p has a
check on TYPE_MODE so you'll get a verification failure at -O on the attached
testcase because FRE builds a VIEW_CONVERT_EXPR with different sizes.
Tested on i586-suse-linux, applied on the mainline as obvious.
2011-12-09 Eric Botcazou <ebotca...@adacore.com>
* gimple-fold.c (gimple_fold_stmt_to_constant_1) <GIMPLE_UNARY_RHS>:
Also check the TYPE_MODE to recognize useless pointer conversions.
2011-12-09 Eric Botcazou <ebotca...@adacore.com>
* gcc.c-torture/compile/20111209-1.c: New test.
--
Eric Botcazou
Index: gimple-fold.c
===================================================================
--- gimple-fold.c (revision 182102)
+++ gimple-fold.c (working copy)
@@ -2517,8 +2517,10 @@ gimple_fold_stmt_to_constant_1 (gimple s
if (CONVERT_EXPR_CODE_P (subcode)
&& POINTER_TYPE_P (TREE_TYPE (lhs))
&& POINTER_TYPE_P (TREE_TYPE (op0))
- && (TYPE_ADDR_SPACE (TREE_TYPE (lhs))
- == TYPE_ADDR_SPACE (TREE_TYPE (op0))))
+ && TYPE_ADDR_SPACE (TREE_TYPE (lhs))
+ == TYPE_ADDR_SPACE (TREE_TYPE (op0))
+ && TYPE_MODE (TREE_TYPE (lhs))
+ == TYPE_MODE (TREE_TYPE (op0)))
return op0;
return
/* { dg-do compile { target s390x-*-* *-*-*vms* } } */
typedef char* char_ptr32 __attribute__ ((mode(SI)));
char_ptr32 getenv (const char *name);
unsigned long strlen (const char *str);
void
__gnat_getenv (char *name, int *len, char **value)
{
*value = getenv (name);
*len = strlen (*value);
}
