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Re: Modifying ARM code generator for elimination of 8bit writes - need help
- From: Wolfgang Mües <wolfgang at iksw-muees dot de>
- To: Rask Ingemann Lambertsen <rask at sygehus dot dk>
- Cc: gcc at gcc dot gnu dot org
- Date: Sat, 12 Aug 2006 14:40:49 +0200
- Subject: Re: Modifying ARM code generator for elimination of 8bit writes - need help
- References: <200605282223.33002.wolfgang@iksw-muees.de> <200608052103.34614.wolfgang@iksw-muees.de> <20060806000510.GA22198@sygehus.dk>
Rask,
On Sunday 06 August 2006 02:05, Rask Ingemann Lambertsen wrote:
> Yes, it only cures the symptom, but it could take a lot of time to
> find the cause, and the gain is small, so I think it is OK to leave
> it like this for now.
OK.
> This insn was generated from the "reload_outqi" pattern. I don't
> completely understand why it isn't recognized. The (subreg:QI (reg:DI
> 11 fp) 0) part won't be matched by (match_scratch ...), but
> simplify_gen_subreg() should have simplified it to (reg:QI 11 fp)
> since this is one of the main purposes of having
> simplify_(gen_)subreg() in the first place. Try changing
>
> operands[3] = simplify_gen_subreg (QImode, operands[2], DImode,
> 0);
>
> into
>
> operands[3] = gen_rtx_REG (QImode, REGNO (operands[2]));
>
> (in "reload_outqi") and see if that works.
Yes, it works. Kernel and userland are compiling now. I can't find any
errors in the generated code. Many thanks!
regards
Wolfgang
--
We're back to the times when men were men
and wrote their own device drivers.
(Linus Torvalds)