Re: [PATCH 2/2] RISC-V: Support assembler modifier %got_pcrel_hi.

[Fangrui Song <i at maskray dot me>]

On 2020-03-03, Jim Wilson wrote:
> On Tue, Mar 3, 2020@2:22 AM Nelson Chu <nelson.chu@sifive.com> wrote:
> >         gas/
> >         * config/tc-riscv.c: Support the modifier %got_pcrel_hi.
> >         * doc/c-riscv.texi: Add documentation.
> >         * testsuite/gas/riscv/no-relax-reloc.d: Add test case for the new
> >         modifier %got_pcrel_hi.
> >         * testsuite/gas/riscv/no-relax-reloc.s: Likewise.
> >         * testsuite/gas/riscv/relax-reloc.d: Likewise.
> >         * testsuite/gas/riscv/relax-reloc.s: Likewise.
>
> This looks good.  I'd just suggest some minor doc fixes to be
> consistent with suggestions for the first patch.
>
> > +@item %got_pcrel_hi(@var{symbol}
> > +The high 20-bit of relative address between pc and the GOT entry of
> > +@var{symbol}.  This is usually used with the %pcrel_lo to access the GOT entry.
>
> 20-bit -> 20 bits
> "the %pcrel_lo" -> "%pcrel_lo" or "the %pcrel_lo modifier"
>
> > +@smallexample
> > +@var{label}:
> > +       auipc           a0, %got_pcrel_hi(@var{symbol}) // R_RISCV_GOT_HI20
> > +       addi/load/store a0, a0, %pcrel_lo(@var{label})  // R_RISCV_PCREL_LO12_I/S
> > +@end smallexample
> > +
> > +Also, the pseudo la instruction with PIC has the similar behavior.
>
> "the similar" -> "similar" or "the same"
>
> Jim

What if %got_pcrel_hi refers to a STB_LOCAL symbol? For example,

auipc a0, %got_pcrel_hi(.L1)

It may be worth a test.

FWIW, llvm-mc -triple=riscv64 -filetype=obj a.s # create a R_RISCV_GOT_HI20 referencing .L1
There is no special treatment.