http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51895
--- Comment #8 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-01-19
13:17:25 UTC ---
For example (untested, and probably completely bogus):
Index: expr.c
===================================================================
--- expr.c (revision 183296)
+++ expr.c (working copy)
@@ -1517,7 +1517,9 @@ move_block_to_reg (int regno, rtx x, int
for (i = 0; i < nregs; i++)
emit_move_insn (gen_rtx_REG (word_mode, regno + i),
- operand_subword_force (x, i, mode));
+ operand_subword_force (x, i,
+ CONSTANT_P (x)
+ ? mode : GET_MODE (x)));
}
/* Copy all or part of a BLKmode value X out of registers starting at REGNO.
As written elsewhere operand_subword* should be deprecated ... so maybe
we can use sth else in move_block_to_reg?
The same effect could be achieved by changing operand_subword to adhere
to its documentation and ignore mode if op is !CONST_INT_P ... thus
Index: emit-rtl.c
===================================================================
--- emit-rtl.c (revision 183296)
+++ emit-rtl.c (working copy)
@@ -1367,7 +1367,7 @@ paradoxical_subreg_p (const_rtx x)
rtx
operand_subword (rtx op, unsigned int offset, int validate_address, enum
machine_mode mode)
{
- if (mode == VOIDmode)
+ if (!CONST_INT_P (op))
mode = GET_MODE (op);
gcc_assert (mode != VOIDmode);
Both fix the testcase.
