https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94216
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I wonder if we shouldn't do:
--- gcc/fold-const.c.jj 2020-03-18 12:47:36.000000000 +0100
+++ gcc/fold-const.c 2020-03-18 17:34:14.586455801 +0100
@@ -82,6 +82,7 @@ along with GCC; see the file COPYING3.
#include "attribs.h"
#include "tree-vector-builder.h"
#include "vec-perm-indices.h"
+#include "tree-ssa.h"
/* Nonzero if we are folding constants inside an initializer; zero
otherwise. */
@@ -10262,6 +10263,10 @@ fold_binary_loc (location_t loc, enum tr
switch (code)
{
case MEM_REF:
+ STRIP_USELESS_TYPE_CONVERSION (arg0);
+ if (arg0 != op0)
+ return fold_build2 (MEM_REF, type, arg0, op1);
+
/* MEM[&MEM[p, CST1], CST2] -> MEM[p, CST1 + CST2]. */
if (TREE_CODE (arg0) == ADDR_EXPR
&& TREE_CODE (TREE_OPERAND (arg0, 0)) == MEM_REF)
to catch all similar issues. Otherwise, we'd need to strip the useless type
conversion at least in the case which triggers this:
return fold_build2 (MEM_REF, type,
build_fold_addr_expr (base),
int_const_binop (PLUS_EXPR, arg1,
size_int (coffset)));
a few lines below this, where build_fold_addr_expr now returns a NOP_EXPR that
we really want to strip again, even when op0 wasn't a NOP_EXPR.
