"Tomas Svensson" <[EMAIL PROTECTED]> writes:
> I am still porting gcc v4.1.2 to a new risc architecture, and this
> time my problem is that when compiling with -O2 turned on, every insn
> with a (use ..) side effect expression, eg.
>
> (define_expand "sibcall"
> [(parallel [(call (match_operand 0 "" "")
> (match_operand 1 "" ""))
> (use (match_operand 2 "" ""))
> (use (match_operand 3 "" ""))])]
> "TARGET_SIBCALL"
> {
> if (operands[3] == NULL_RTX)
> operands[3] = const0_rtx;
>
> internal_expand_sibcall (0, XEXP (operands[0], 0), operands[1]);
> DONE;
> })
>
> causes the compiler to fail with an internal compiler error in add_clobbers.
>
> I have looked at it in gdb and it fails on reaching the
> gcc_unreachable() in add_clobbers, which happens because add_clobbers
> is called (at combine.c:9576) with an insn_code_number that it does
> not recognize.
>
> Everything works fine when optimization is turned off. What is it that
> gcc does differently when optimizing, that might cause this to happen?
Sounds like your insn is not recognized. That means that there is no
define_insn in your MD file which matches the insn you are generating.
Note that the pattern you show for the define_expand is documentation
only; because your code inclues DONE, the pattern is not actually
used. You didn't show which insn was actually generated. Most likely
there is no define_insn for that insn.
Ian
