On Sun, Jun 26, 2022 at 7:53 AM Takayuki 'January June' Suwa
<jjsuwa_sys3...@yahoo.co.jp> wrote:
>
> Such constants are often subject to the constant synthesis:
>
> int test(int a) {
> return a - 31999;
> }
>
> test:
> movi a3, 1
> addmi a3, a3, -0x7d00
> add a2, a2, a3
> ret
>
> This patch optimizes such case as follows:
>
> test:
> addi a2, a2, 1
> addmi a2, a2, -0x7d00
> ret
>
> gcc/ChangeLog:
>
> * config/xtensa/xtensa.md:
> Suppress unnecessary emitting nop insn in the split patterns for
> integer/FP constant synthesis, and add new peephole2 pattern that
> folds such synthesized additions.
> ---
> gcc/config/xtensa/xtensa.md | 35 +++++++++++++++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
Regtested for target=xtensa-linux-uclibc, no new regressions.
Committed to master.
--
Thanks.
-- Max
