m68k.md contains the following insn:
(define_insn ""
[(set (match_operand:SI 0 "nonimmediate_operand" "=&d")
(zero_extract:SI (match_operand:SI 1 "register_operand" "do")
(match_operand:SI 2 "const_int_operand" "n")
(match_operand:SI 3 "const_int_operand" "n")))]
"TARGET_68020 && TARGET_BITFIELD
&& (INTVAL (operands[2]) == 8 || INTVAL (operands[2]) == 16)
&& INTVAL (operands[3]) % INTVAL (operands[2]) == 0
&& (GET_CODE (operands[1]) == REG
|| ! mode_dependent_address_p (XEXP (operands[1], 0),
MEM_ADDR_SPACE (operands[1])))"
{
cc_status.flags |= CC_NOT_NEGATIVE;
if (REG_P (operands[1]))
{
if (INTVAL (operands[2]) + INTVAL (operands[3]) != 32)
return "bfextu %1{%b3:%b2},%0";
}
else
operands[1]
= adjust_address (operands[1], SImode, INTVAL (operands[3]) / 8);
output_asm_insn ("clr%.l %0", operands);
if (GET_CODE (operands[0]) == MEM)
operands[0] = adjust_address (operands[0],
INTVAL (operands[2]) == 8 ? QImode : HImode,
(32 - INTVAL (operands[1])) / 8);
if (INTVAL (operands[2]) == 8)
return "move%.b %1,%0";
return "move%.w %1,%0";
})
It is my understanding that given the register_operand predicate on op1
it can never be a MEM expressions, thus the call to
mode_dependent_address_p in the condition is useless, and the "o"
constraint is redundant. Similarily, even though op0 is matched with
nonimmediate_operand, after reload it is always a REG due to the "d"
constraint, thus the the MEM check in the body can never be true. Is
that correct?
(The immediate problem is that op1 can be (SUBREG (REG)), which is then
passed to MEM_ADDR_SPACE. Before r11511, the predicate on op1 was
nonimmediate_operand, thus the mode_dependent_address_p check made
sense.)
Andreas.
--
Andreas Schwab, sch...@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."
