On Thu, Jul 11, 2024 at 04:29:19PM +0200, Stefan Schulze Frielinghaus wrote:
> During machine reorg we optimize backward jumps and transform insns as
> e.g.
>
> (jump_insn 118 117 119 (set (pc)
> (if_then_else (ne (reg:CCRAW 33 %cc)
> (const_int 8 [0x8]))
> (label_ref 134)
> (pc))) "dec_math_1.f90":204:8 discrim 1 2161 {*cjump_64}
> (expr_list:REG_DEAD (reg:CCRAW 33 %cc)
> (int_list:REG_BR_PROB 719407028 (nil)))
> -> 134)
>
> into
>
> (jump_insn 118 117 432 (set (pc)
> (if_then_else (ne (reg:CCRAW 33 %cc)
> (const_int 8 [0x8]))
> (pc)
> (label_ref 433))) "dec_math_1.f90":204:8 discrim 1 -1
> (expr_list:REG_DEAD (reg:CCRAW 33 %cc)
> (int_list:REG_BR_PROB 719407028 (nil)))
> -> 433)
>
> The latter is not recognized anymore since *icjump_64 only matches
> CC_REGNUM against zero. Fixed by aligning *cjump_64 and *icjump_64.
>
> gcc/ChangeLog:
>
> * config/s390/s390.md (*icjump_64): Allow raw CC comparisons,
> i.e., any constant integer between 0 and 15 for CC comparisons.
> ---
> Bootstrap and regtest or still running. Assuming no regressions, ok
> for {mainline,11,12,13,14}? Would be great to see this in 14.2 RC :)
I didn't have the schedule for 11.5 RC in mind which is tomorrow and the
release a week afterwards. I hope this is still appropriate for 11.5?
Cheers,
Stefan
>
> gcc/config/s390/s390.md | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/gcc/config/s390/s390.md b/gcc/config/s390/s390.md
> index f5d7003dfad..d3931b09417 100644
> --- a/gcc/config/s390/s390.md
> +++ b/gcc/config/s390/s390.md
> @@ -9556,7 +9556,8 @@
> (define_insn "*icjump_64"
> [(set (pc)
> (if_then_else
> - (match_operator 1 "s390_comparison" [(reg CC_REGNUM) (const_int
> 0)])
> + (match_operator 1 "s390_comparison" [(reg CC_REGNUM)
> + (match_operand 2
> "const_int_operand" "")])
> (pc)
> (label_ref (match_operand 0 "" ""))))]
> ""
> --
> 2.45.2
>
