Could not split insn

[Hans-Peter Nilsson]

On Mon, 13 Sep 2004, Petar Penchev wrote:
>
> Hello all,
> I have define "iorsi3" instruction in my .md file as follows :
>
> (define_insn_and_split "iorsi3"
>    [(set (match_operand:SI 0 "nonimmediate_nonstack_operand"		"=b,  o")
> 	(ior:SI (match_operand:SI 1 "nonimmediate_nonstack_operand"	"%0,  0")
> 		  (match_operand:SI 2 "general_operand"				"boi, boi")))
>     (clobber (match_scratch:HI 3							"=X,  &r"))]
>    ""
>    "#"
>    "reload_completed"
>    [(const_int 0)]
>    "split_logical(HImode, IOR, operands);
>     DONE;"
> )
>
> Where constraint 'b' is general-purpose register, which supports SImode.
> I tried to compile newlib with optimization -O1 and I have got folowing
> message:
>
> ../../../../../newlib_src/newlib/libc/stdlib/mprec.c: In function
> `_lshift':
> ../../../../../newlib_src/newlib/libc/stdlib/mprec.c:515: error: could not
> split insn
> (insn 222 278 279 (parallel [
>              (set (reg:SI 0 A)
>                  (ior:SI (reg:SI 0 A)
>                      (const_int 0 [0x0])))
>              (clobber (scratch:HI))
>          ]) 62 {iorsi3} (insn_list 96 (nil))
>      (expr_list:REG_UNUSED (scratch:HI)
>          (nil)))
> ../../../../../newlib_src/newlib/libc/stdlib/mprec.c:515: internal
> compiler error: in final_scan_insn, at final.c:2429
>
> Register A is accessible in SImode.
> But it seems to me that pattern should be matched by the split.

That depends entirely on the splitter code in split_logical(),
which you didn't show.

Besides, the constraint "o" seems wrong: it allows any
offsettable operand, which includes stack operands, supposedly
refused by nonimmediate_nonstack_operand.  You must not allow
operands in a constraint that are disallowed by the predicate.

> Does anybody have met the same problem ?

<evil>
I suppose you mean generally, bugs in an initial port?  You bet.
You *really* have to debug this on your own; sending port
snippets will not work.  Luckily, all the source code is there.
</evil>

;-)

brgds, H-P