instruction not recognized (genrecog bug?)

[Ian Dall <ian at beware dot dropbear dot id dot au>]

In trying to bootstrap egcs-20000103 configured for ns32k-pc532, I find
the following error:

/usr/cygnus/TBD-TBD/share/bison.simple:692: Unrecognizable insn:
(insn 2318 2246 334 (set (reg:SI 0 r0)
        (plus:SI (mult:SI (reg:SI 0 r0)
                (const_int 4 [0x4]))
            (mem:SI (plus:SI (reg:SI 24 fp)
                    (const_int -2820 [0xfffff4fc])) 0))) -1 (nil)
    (nil))
/usr/cygnus/TBD-TBD/share/bison.simple:692: Internal compiler error in `extract_insn', at recog.c:2043


The interesting thing is that this seems to me like a bug in genrecog.c
There is an insn in the ns32k.md which should match as far as I can see:

(define_insn ""
  [(set (match_operand:SI 0 "general_operand" "=g<")
	(match_operand:QI 1 "address_operand" "p"))]
  ""
  "*
{...})

and I have checked that the second operand

(plus:SI (mult:SI (reg:SI 0 r0)
                (const_int 4 [0x4]))
            (mem:SI (plus:SI (reg:SI 24 fp)
                    (const_int -2820 [0xfffff4fc])) 0))

really is an "address_operand" by calling it from gdb. The first
operand is clearly a general_operand so why doesn't it match? Is this
a bug in genrecog.c or do I misunderstand something? Is the QI mode on
the second match_operand correct?

Following progress through insn_recog.c, the following bit of code
stands out:

 L815: ATTRIBUTE_UNUSED_LABEL
  x1 = XEXP (x0, 1);
  if (GET_MODE (x1) == SImode)
    goto L1421;
  if (address_operand (x1, QImode))
    {
      operands[1] = x1;
      return 158;
    }
  x1 = XEXP (x0, 0);
  goto L1095;


At this point, x1 is the second operand of the offending insn which is SImode
so the L1421 branch gets taken and the address_operand test is not performed.
I think "return 158" would be the correct behaviour.

I would appreciate any tips.

Ian