struct table_elt *p
= lookup (x, SAFE_HASH (x, VOIDmode), GET_MODE (x));
- /* If we are looking for a CONST_INT, the mode doesn't really matter, as
- long as we are narrowing. So if we looked in vain for a mode narrower
- than word_mode before, look for word_mode now. */
- if (p == 0 && code == CONST_INT
- && GET_MODE_SIZE (GET_MODE (x)) < GET_MODE_SIZE (word_mode))
- {
- x = copy_rtx (x);
- PUT_MODE (x, word_mode);
- p = lookup (x, SAFE_HASH (x, VOIDmode), word_mode);
- }
-
if (p == 0)
return 0;
int is_shift
= (code == ASHIFT || code == ASHIFTRT || code == LSHIFTRT);
rtx y, inner_const, new_const;
+ rtx canon_const_arg1 = const_arg1;
enum rtx_code associate_code;
if (is_shift
|| INTVAL (const_arg1) < 0))
{
if (SHIFT_COUNT_TRUNCATED)
- const_arg1 = GEN_INT (INTVAL (const_arg1)
- & (GET_MODE_BITSIZE (mode) - 1));
+ canon_const_arg1 = GEN_INT (INTVAL (const_arg1)
+ & (GET_MODE_BITSIZE (mode)
+ - 1));
else
break;
}
associate_code = (is_shift || code == MINUS ? PLUS : code);
new_const = simplify_binary_operation (associate_code, mode,
- const_arg1, inner_const);
+ canon_const_arg1,
+ inner_const);
if (new_const == 0)
break;
if (GET_CODE (x) == SUBREG)
{
+ enum machine_mode mode = GET_MODE (x);
+ enum machine_mode imode = GET_MODE (SUBREG_REG (x));
rtx new_rtx;
/* See if we previously assigned a constant value to this SUBREG. */
|| (new_rtx = lookup_as_function (x, CONST_FIXED)) != 0)
return new_rtx;
+ /* If we didn't and if doing so makes sense, see if we previously
+ assigned a constant value to the enclosing word mode SUBREG. */
+ if (GET_MODE_SIZE (mode) < GET_MODE_SIZE (word_mode)
+ && GET_MODE_SIZE (word_mode) < GET_MODE_SIZE (imode))
+ {
+ int byte = SUBREG_BYTE (x) - subreg_lowpart_offset (mode, word_mode);
+ if (byte >= 0 && (byte % UNITS_PER_WORD) == 0)
+ {
+ rtx y = gen_rtx_SUBREG (word_mode, SUBREG_REG (x), byte);
+ new_rtx = lookup_as_function (y, CONST_INT);
+ if (new_rtx)
+ return gen_lowpart (mode, new_rtx);
+ }
+ }
+
+ /* Otherwise see if we already have a constant for the inner REG. */
if (REG_P (SUBREG_REG (x))
&& (new_rtx = equiv_constant (SUBREG_REG (x))) != 0)
- return simplify_subreg (GET_MODE (x), SUBREG_REG (x),
- GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x));
+ return simplify_subreg (mode, new_rtx, imode, SUBREG_BYTE (x));
return 0;
}
enum machine_mode wider_mode;
for (wider_mode = GET_MODE_WIDER_MODE (mode);
- GET_MODE_BITSIZE (wider_mode) <= BITS_PER_WORD
+ wider_mode != VOIDmode
+ && GET_MODE_BITSIZE (wider_mode) <= BITS_PER_WORD
&& src_related == 0;
wider_mode = GET_MODE_WIDER_MODE (wider_mode))
{