* [PATCH] RISC-V: costs: handle BSWAP
@ 2022-11-08 19:54 Philipp Tomsich
2022-11-09 2:57 ` Jeff Law
0 siblings, 1 reply; 7+ messages in thread
From: Philipp Tomsich @ 2022-11-08 19:54 UTC (permalink / raw)
To: gcc-patches
Cc: Palmer Dabbelt, Kito Cheng, Christoph Muellner, Vineet Gupta,
Jeff Law, Philipp Tomsich
The BSWAP operation is not handled in rtx_costs. Add it.
With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
it will expand into two.
gcc/ChangeLog:
* config/riscv/riscv.c (rtx_costs): Add BSWAP.
---
gcc/config/riscv/riscv.cc | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 32f9ef9ade9..ab6c745c722 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -2562,6 +2562,16 @@ riscv_rtx_costs (rtx x, machine_mode mode, int outer_code, int opno ATTRIBUTE_UN
*total = riscv_extend_cost (XEXP (x, 0), GET_CODE (x) == ZERO_EXTEND);
return false;
+ case BSWAP:
+ if (TARGET_ZBB)
+ {
+ /* RISC-V only defines rev8 for XLEN, so we will need an extra
+ shift-right instruction for smaller modes. */
+ *total = COSTS_N_INSNS (mode == word_mode ? 1 : 2);
+ return true;
+ }
+ return false;
+
case FLOAT:
case UNSIGNED_FLOAT:
case FIX:
--
2.34.1
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH] RISC-V: costs: handle BSWAP
2022-11-08 19:54 [PATCH] RISC-V: costs: handle BSWAP Philipp Tomsich
@ 2022-11-09 2:57 ` Jeff Law
2022-11-09 3:15 ` Palmer Dabbelt
0 siblings, 1 reply; 7+ messages in thread
From: Jeff Law @ 2022-11-09 2:57 UTC (permalink / raw)
To: Philipp Tomsich, gcc-patches
Cc: Palmer Dabbelt, Kito Cheng, Christoph Muellner, Vineet Gupta, Jeff Law
On 11/8/22 12:54, Philipp Tomsich wrote:
> The BSWAP operation is not handled in rtx_costs. Add it.
>
> With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
> it will expand into two.
>
> gcc/ChangeLog:
>
> * config/riscv/riscv.c (rtx_costs): Add BSWAP.
OK.
Jeff
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] RISC-V: costs: handle BSWAP
2022-11-09 2:57 ` Jeff Law
@ 2022-11-09 3:15 ` Palmer Dabbelt
2022-11-09 4:43 ` Andrew Pinski
2022-11-09 9:33 ` Philipp Tomsich
0 siblings, 2 replies; 7+ messages in thread
From: Palmer Dabbelt @ 2022-11-09 3:15 UTC (permalink / raw)
To: jeffreyalaw
Cc: philipp.tomsich, gcc-patches, Kito Cheng, christoph.muellner,
Vineet Gupta, jlaw
On Tue, 08 Nov 2022 18:57:26 PST (-0800), jeffreyalaw@gmail.com wrote:
>
> On 11/8/22 12:54, Philipp Tomsich wrote:
>> The BSWAP operation is not handled in rtx_costs. Add it.
>>
>> With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
>> it will expand into two.
>>
>> gcc/ChangeLog:
>>
>> * config/riscv/riscv.c (rtx_costs): Add BSWAP.
>
> OK.
It's riscv_rtx_costs.
(I don't usually read ChangeLog entries that closely, just happened to
stumble on it when poking around.)
>
> Jeff
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] RISC-V: costs: handle BSWAP
2022-11-09 3:15 ` Palmer Dabbelt
@ 2022-11-09 4:43 ` Andrew Pinski
2022-11-09 4:53 ` Palmer Dabbelt
2022-11-09 9:27 ` Philipp Tomsich
2022-11-09 9:33 ` Philipp Tomsich
1 sibling, 2 replies; 7+ messages in thread
From: Andrew Pinski @ 2022-11-09 4:43 UTC (permalink / raw)
To: Palmer Dabbelt
Cc: jeffreyalaw, philipp.tomsich, gcc-patches, Kito Cheng,
christoph.muellner, Vineet Gupta, jlaw
On Tue, Nov 8, 2022 at 7:16 PM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> On Tue, 08 Nov 2022 18:57:26 PST (-0800), jeffreyalaw@gmail.com wrote:
> >
> > On 11/8/22 12:54, Philipp Tomsich wrote:
> >> The BSWAP operation is not handled in rtx_costs. Add it.
> >>
> >> With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
> >> it will expand into two.
> >>
> >> gcc/ChangeLog:
> >>
> >> * config/riscv/riscv.c (rtx_costs): Add BSWAP.
> >
> > OK.
>
> It's riscv_rtx_costs.
>
> (I don't usually read ChangeLog entries that closely, just happened to
> stumble on it when poking around.)
Using contrib/git-commit-mklog.py can help here to make sure you
always get the correct format for the changelog and it does a decent
job of figuring out function names too.
You can also use contrib/gcc-git-customization.sh to install it such
that you can use it when doing git commits.
After invoking that inside the GCC git; you can just do "git
gcc-commit-mklog ...." Where .... would be what you normally put for
"git commit" (but as if in the toplevel directory).
Thanks,
Andrew Pinski
>
>
> >
> > Jeff
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] RISC-V: costs: handle BSWAP
2022-11-09 4:43 ` Andrew Pinski
@ 2022-11-09 4:53 ` Palmer Dabbelt
2022-11-09 9:27 ` Philipp Tomsich
1 sibling, 0 replies; 7+ messages in thread
From: Palmer Dabbelt @ 2022-11-09 4:53 UTC (permalink / raw)
To: pinskia
Cc: jeffreyalaw, philipp.tomsich, gcc-patches, Kito Cheng,
christoph.muellner, Vineet Gupta, jlaw
On Tue, 08 Nov 2022 20:43:20 PST (-0800), pinskia@gmail.com wrote:
> On Tue, Nov 8, 2022 at 7:16 PM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>>
>> On Tue, 08 Nov 2022 18:57:26 PST (-0800), jeffreyalaw@gmail.com wrote:
>> >
>> > On 11/8/22 12:54, Philipp Tomsich wrote:
>> >> The BSWAP operation is not handled in rtx_costs. Add it.
>> >>
>> >> With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
>> >> it will expand into two.
>> >>
>> >> gcc/ChangeLog:
>> >>
>> >> * config/riscv/riscv.c (rtx_costs): Add BSWAP.
>> >
>> > OK.
>>
>> It's riscv_rtx_costs.
>>
>> (I don't usually read ChangeLog entries that closely, just happened to
>> stumble on it when poking around.)
>
> Using contrib/git-commit-mklog.py can help here to make sure you
> always get the correct format for the changelog and it does a decent
> job of figuring out function names too.
> You can also use contrib/gcc-git-customization.sh to install it such
> that you can use it when doing git commits.
> After invoking that inside the GCC git; you can just do "git
> gcc-commit-mklog ...." Where .... would be what you normally put for
> "git commit" (but as if in the toplevel directory).
Thanks, that's awesome.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] RISC-V: costs: handle BSWAP
2022-11-09 4:43 ` Andrew Pinski
2022-11-09 4:53 ` Palmer Dabbelt
@ 2022-11-09 9:27 ` Philipp Tomsich
1 sibling, 0 replies; 7+ messages in thread
From: Philipp Tomsich @ 2022-11-09 9:27 UTC (permalink / raw)
To: Andrew Pinski
Cc: Palmer Dabbelt, jeffreyalaw, gcc-patches, Kito Cheng,
christoph.muellner, Vineet Gupta, jlaw
On Wed, 9 Nov 2022 at 05:43, Andrew Pinski <pinskia@gmail.com> wrote:
>
> On Tue, Nov 8, 2022 at 7:16 PM Palmer Dabbelt <palmer@rivosinc.com> wrote:
> >
> > On Tue, 08 Nov 2022 18:57:26 PST (-0800), jeffreyalaw@gmail.com wrote:
> > >
> > > On 11/8/22 12:54, Philipp Tomsich wrote:
> > >> The BSWAP operation is not handled in rtx_costs. Add it.
> > >>
> > >> With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
> > >> it will expand into two.
> > >>
> > >> gcc/ChangeLog:
> > >>
> > >> * config/riscv/riscv.c (rtx_costs): Add BSWAP.
> > >
> > > OK.
> >
> > It's riscv_rtx_costs.
> >
> > (I don't usually read ChangeLog entries that closely, just happened to
> > stumble on it when poking around.)
>
> Using contrib/git-commit-mklog.py can help here to make sure you
> always get the correct format for the changelog and it does a decent
> job of figuring out function names too.
> You can also use contrib/gcc-git-customization.sh to install it such
> that you can use it when doing git commits.
> After invoking that inside the GCC git; you can just do "git
> gcc-commit-mklog ...." Where .... would be what you normally put for
> "git commit" (but as if in the toplevel directory).
We always pass them through contrib/mklog,py (or git-commit-mklog.py,
which invokes it) anyway, but (as the ".c" in the filename indicates)
this one hasn't been refreshed in over a year's time.
Don't worry, this will need to get adjusted again once I merge it (as
the commit hooks won't let it pass).
Philipp.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] RISC-V: costs: handle BSWAP
2022-11-09 3:15 ` Palmer Dabbelt
2022-11-09 4:43 ` Andrew Pinski
@ 2022-11-09 9:33 ` Philipp Tomsich
1 sibling, 0 replies; 7+ messages in thread
From: Philipp Tomsich @ 2022-11-09 9:33 UTC (permalink / raw)
To: Palmer Dabbelt
Cc: jeffreyalaw, gcc-patches, Kito Cheng, christoph.muellner,
Vineet Gupta, jlaw
Applied to master, with the commit-message regenerated as:
gcc/ChangeLog:
* config/riscv/riscv.cc (riscv_rtx_costs): Add BSWAP.
Thanks,
Philipp.
On Wed, 9 Nov 2022 at 04:15, Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> On Tue, 08 Nov 2022 18:57:26 PST (-0800), jeffreyalaw@gmail.com wrote:
> >
> > On 11/8/22 12:54, Philipp Tomsich wrote:
> >> The BSWAP operation is not handled in rtx_costs. Add it.
> >>
> >> With Zbb, BSWAP for XLEN is a single instruction; for smaller modes,
> >> it will expand into two.
> >>
> >> gcc/ChangeLog:
> >>
> >> * config/riscv/riscv.c (rtx_costs): Add BSWAP.
> >
> > OK.
>
> It's riscv_rtx_costs.
>
> (I don't usually read ChangeLog entries that closely, just happened to
> stumble on it when poking around.)
>
>
> >
> > Jeff
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2022-11-09 9:34 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
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2022-11-08 19:54 [PATCH] RISC-V: costs: handle BSWAP Philipp Tomsich
2022-11-09 2:57 ` Jeff Law
2022-11-09 3:15 ` Palmer Dabbelt
2022-11-09 4:43 ` Andrew Pinski
2022-11-09 4:53 ` Palmer Dabbelt
2022-11-09 9:27 ` Philipp Tomsich
2022-11-09 9:33 ` Philipp Tomsich
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