RISC-V: Don't generate branch/jump relocation if symbol is local when no-relax.
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Commit Message
Refer to commit, dff565fcca8137954d6ad571ef39f6aec5c0429c. Theoretically,
assembler don't need to generate the pc-relative relocation and the refered
local .L symbol when relaxation is disabled. The above commit improved the
pcrel_hi/pcrel_lo relocations, and this commit improves branch and jump
relocations.
Passed the gcc/binutils regressions of riscv-gnu-toolchain.
gas/
* config/tc-riscv.c (md_apply_fix): Raise fixP->fx_done for all
branch and jump relocations when -mno-relax.
---
gas/config/tc-riscv.c | 8 ++++++++
1 file changed, 8 insertions(+)
Comments
On Jan 29 2024, Nelson Chu wrote:
> Refer to commit, dff565fcca8137954d6ad571ef39f6aec5c0429c. Theoretically,
> assembler don't need to generate the pc-relative relocation and the refered
> local .L symbol when relaxation is disabled. The above commit improved the
> pcrel_hi/pcrel_lo relocations, and this commit improves branch and jump
> relocations.
>
> Passed the gcc/binutils regressions of riscv-gnu-toolchain.
>
> gas/
> * config/tc-riscv.c (md_apply_fix): Raise fixP->fx_done for all
> branch and jump relocations when -mno-relax.
Is this related to PR30591?
On Tue, Jan 30, 2024 at 6:00 PM Andreas Schwab <schwab@suse.de> wrote:
> On Jan 29 2024, Nelson Chu wrote:
>
> > Refer to commit, dff565fcca8137954d6ad571ef39f6aec5c0429c.
> Theoretically,
> > assembler don't need to generate the pc-relative relocation and the
> refered
> > local .L symbol when relaxation is disabled. The above commit improved
> the
> > pcrel_hi/pcrel_lo relocations, and this commit improves branch and jump
> > relocations.
> >
> > Passed the gcc/binutils regressions of riscv-gnu-toolchain.
> >
> > gas/
> > * config/tc-riscv.c (md_apply_fix): Raise fixP->fx_done for all
> > branch and jump relocations when -mno-relax.
>
> Is this related to PR30591?
>
Yeah, it seems like the same stuff :)
Thanks
Nelson
On Jan 29 2024, Nelson Chu wrote:
> Refer to commit, dff565fcca8137954d6ad571ef39f6aec5c0429c. Theoretically,
> assembler don't need to generate the pc-relative relocation and the refered
> local .L symbol when relaxation is disabled. The above commit improved the
> pcrel_hi/pcrel_lo relocations, and this commit improves branch and jump
> relocations.
This reduces the number of relocations for .text in the amdgpu kernel
module from 217597 to 101552.
Thanks for the information! I will commit it before this week ;)
Thanks
Nelson
On Mon, Feb 19, 2024 at 10:35 PM Andreas Schwab <schwab@suse.de> wrote:
> On Jan 29 2024, Nelson Chu wrote:
>
> > Refer to commit, dff565fcca8137954d6ad571ef39f6aec5c0429c.
> Theoretically,
> > assembler don't need to generate the pc-relative relocation and the
> refered
> > local .L symbol when relaxation is disabled. The above commit improved
> the
> > pcrel_hi/pcrel_lo relocations, and this commit improves branch and jump
> > relocations.
>
> This reduces the number of relocations for .text in the amdgpu kernel
> module from 217597 to 101552.
>
> --
> Andreas Schwab, SUSE Labs, schwab@suse.de
> GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
> "And now for something completely different."
>
Committed :-)
Nelson
On Tue, Feb 20, 2024 at 8:19 AM Nelson Chu <nelson@rivosinc.com> wrote:
> Thanks for the information! I will commit it before this week ;)
>
> Thanks
> Nelson
>
> On Mon, Feb 19, 2024 at 10:35 PM Andreas Schwab <schwab@suse.de> wrote:
>
>> On Jan 29 2024, Nelson Chu wrote:
>>
>> > Refer to commit, dff565fcca8137954d6ad571ef39f6aec5c0429c.
>> Theoretically,
>> > assembler don't need to generate the pc-relative relocation and the
>> refered
>> > local .L symbol when relaxation is disabled. The above commit improved
>> the
>> > pcrel_hi/pcrel_lo relocations, and this commit improves branch and jump
>> > relocations.
>>
>> This reduces the number of relocations for .text in the amdgpu kernel
>> module from 217597 to 101552.
>>
>> --
>> Andreas Schwab, SUSE Labs, schwab@suse.de
>> GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
>> "And now for something completely different."
>>
>
@@ -4390,6 +4390,8 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
bfd_vma target = S_GET_VALUE (fixP->fx_addsy) + *valP;
bfd_vma delta = target - md_pcrel_from (fixP);
bfd_putl32 (bfd_getl32 (buf) | ENCODE_JTYPE_IMM (delta), buf);
+ if (!riscv_opts.relax && S_IS_LOCAL (fixP->fx_addsy))
+ fixP->fx_done = 1;
}
break;
@@ -4400,6 +4402,8 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
bfd_vma target = S_GET_VALUE (fixP->fx_addsy) + *valP;
bfd_vma delta = target - md_pcrel_from (fixP);
bfd_putl32 (bfd_getl32 (buf) | ENCODE_BTYPE_IMM (delta), buf);
+ if (!riscv_opts.relax && S_IS_LOCAL (fixP->fx_addsy))
+ fixP->fx_done = 1;
}
break;
@@ -4410,6 +4414,8 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
bfd_vma target = S_GET_VALUE (fixP->fx_addsy) + *valP;
bfd_vma delta = target - md_pcrel_from (fixP);
bfd_putl16 (bfd_getl16 (buf) | ENCODE_CBTYPE_IMM (delta), buf);
+ if (!riscv_opts.relax && S_IS_LOCAL (fixP->fx_addsy))
+ fixP->fx_done = 1;
}
break;
@@ -4420,6 +4426,8 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
bfd_vma target = S_GET_VALUE (fixP->fx_addsy) + *valP;
bfd_vma delta = target - md_pcrel_from (fixP);
bfd_putl16 (bfd_getl16 (buf) | ENCODE_CJTYPE_IMM (delta), buf);
+ if (!riscv_opts.relax && S_IS_LOCAL (fixP->fx_addsy))
+ fixP->fx_done = 1;
}
break;