Re: [PATCH v2] docs: Add 'S' to Machine Constraints for RISC-V

[Kito Cheng <kito.cheng@gmail.com>]

committed to trunk.

On Mon, Jul 12, 2021 at 12:48 PM Fangrui Song <i@maskray.me> wrote:
>
> On 2021-07-12, Kito Cheng wrote:
> >It was undocument before, but it might used in linux kernel for resolve
> >code model issue, so LLVM community suggest we should document that,
> >so that make it become supported/documented/non-internal machine constraints.
> >
> >gcc/ChangeLog:
> >
> >       PR target/101275
> >       * config/riscv/constraints.md ("S"): Update description and remove
> >       @internal.
> >       * doc/md.texi (Machine Constraints): Document the 'S' constraints
> >       for RISC-V.
> >---
> > gcc/config/riscv/constraints.md | 3 +--
> > gcc/doc/md.texi                 | 3 +++
> > 2 files changed, 4 insertions(+), 2 deletions(-)
> >
> >diff --git a/gcc/config/riscv/constraints.md b/gcc/config/riscv/constraints.md
> >index 8c15c6c0486..c87d5b796a5 100644
> >--- a/gcc/config/riscv/constraints.md
> >+++ b/gcc/config/riscv/constraints.md
> >@@ -67,8 +67,7 @@ (define_memory_constraint "A"
> >        (match_test "GET_CODE(XEXP(op,0)) == REG")))
> >
> > (define_constraint "S"
> >-  "@internal
> >-   A constant call address."
> >+  "A constraint that matches an absolute symbolic address."
> >   (match_operand 0 "absolute_symbolic_operand"))
> >
> > (define_constraint "U"
> >diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi
> >index 00caf3844cc..2d120da96cf 100644
> >--- a/gcc/doc/md.texi
> >+++ b/gcc/doc/md.texi
> >@@ -3536,6 +3536,9 @@ A 5-bit unsigned immediate for CSR access instructions.
> > @item A
> > An address that is held in a general-purpose register.
> >
> >+@item S
> >+A constraint that matches an absolute symbolic address.
> >+
> > @end table
> >
> > @item RX---@file{config/rx/constraints.md}
> >--
> >2.31.1
>
> LGTM