struct resources needed, set;
int i;
+ /* If INSN has any REG_UNUSED notes, it can't match anything since we
+ are allowed to not actually assign to such a register. */
+ if (find_reg_note (insn, REG_UNUSED, NULL_RTX) != 0)
+ return 0;
+
/* Scan backwards looking for a match. */
for (trial = PREV_INSN (target); trial; trial = PREV_INSN (trial))
{
resource requirements as we go. */
for (i = XVECLEN (pat, 0) - 1; i > 0; i--)
if (GET_CODE (XVECEXP (pat, 0, i)) == GET_CODE (insn)
- && rtx_equal_p (PATTERN (XVECEXP (pat, 0, i)), ipat))
+ && rtx_equal_p (PATTERN (XVECEXP (pat, 0, i)), ipat)
+ && ! find_reg_note (XVECEXP (pat, 0, i), REG_UNUSED, NULL_RTX))
break;
/* If found a match, exit this loop early. */
break;
}
- else if (GET_CODE (trial) == GET_CODE (insn) && rtx_equal_p (pat, ipat))
+ else if (GET_CODE (trial) == GET_CODE (insn) && rtx_equal_p (pat, ipat)
+ && ! find_reg_note (trial, REG_UNUSED, NULL_RTX))
break;
}