[PATCH v2 0/2] RISC-V: Support ".option [no]exact" assembler directives

[Tsukasa OI]

Hello,

See PATCH 2/2 for the purpose of this patch set.
PATCH 1/2 fixes a bug (which is very important to fix when we implement
the exact mode but already affected ".option norelax" code).


Version 1 (2025-05-13)
=======================
cf. <https://sourceware.org/pipermail/binutils/2025-May/141042.html>

This is the initial proposal.


Version 2 (2025-05-14) - THIS VERSION
======================================
No changes in the code.

*   PATCH 1/2 (Commit message):
    Clarify again that, in the scope of this fix, the relocation is
    optionally removed when the linker relaxation is disabled.
*   PATCH 2/2 (Commit message):
    Notify that the exact mode is already implemented in LLVM.
*   PATCH 2/2 (Documentation):
    *   Imply that there is a small room for minor specification
        change related to ".option exact/noexact".
    *   Document that there are flaky interactions between
        ".option relax/norelax" and ".option exact/noexact"
        and add a warning about them.




Tsukasa OI (2):
  RISC-V: check offsets when linker relaxation is disabled
  RISC-V: Support ".option [no]exact" assembler directives

 gas/config/tc-riscv.c                         |  88 +++++++--
 gas/doc/c-riscv.texi                          |  13 ++
 .../gas/riscv/exact-branch-extern-exact.d     |  32 ++++
 .../gas/riscv/exact-branch-extern-noexact.d   |  50 ++++++
 gas/testsuite/gas/riscv/exact-branch-extern.s |  40 +++++
 .../gas/riscv/exact-branch-local-exact-fail.d |   3 +
 .../gas/riscv/exact-branch-local-exact-fail.l |  43 +++++
 .../gas/riscv/exact-branch-local-exact-ok.d   |  75 ++++++++
 .../gas/riscv/exact-branch-local-noexact.d    | 149 +++++++++++++++
 gas/testsuite/gas/riscv/exact-branch-local.s  | 138 ++++++++++++++
 gas/testsuite/gas/riscv/exact.d               |  15 ++
 gas/testsuite/gas/riscv/exact.s               |  10 ++
 .../gas/riscv/no-relax-branch-offset-fail.d   |   2 +
 .../gas/riscv/no-relax-branch-offset-fail.l   |  11 ++
 .../gas/riscv/no-relax-branch-offset-fail.s   |  23 +++
 .../gas/riscv/no-relax-branch-offset-ok.d     |  17 ++
 .../gas/riscv/no-relax-branch-offset-ok.s     |  17 ++
 .../gas/riscv/no-relax-pcrel-offset-fail-64.d |   2 +
 .../gas/riscv/no-relax-pcrel-offset-fail-64.l |   7 +
 .../gas/riscv/no-relax-pcrel-offset-fail-64.s |  31 ++++
 .../riscv/no-relax-pcrel-offset-fail-not-32.d |  22 +++
 .../gas/riscv/no-relax-pcrel-offset-ok.d      |  21 +++
 .../gas/riscv/no-relax-pcrel-offset-ok.s      |  29 +++
 include/opcode/riscv.h                        |   6 +
 opcodes/riscv-opc.c                           | 170 +++++++++---------
 25 files changed, 914 insertions(+), 100 deletions(-)
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-extern-exact.d
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-extern-noexact.d
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-extern.s
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-local-exact-fail.d
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-local-exact-fail.l
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-local-exact-ok.d
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-local-noexact.d
 create mode 100644 gas/testsuite/gas/riscv/exact-branch-local.s
 create mode 100644 gas/testsuite/gas/riscv/exact.d
 create mode 100644 gas/testsuite/gas/riscv/exact.s
 create mode 100644 gas/testsuite/gas/riscv/no-relax-branch-offset-fail.d
 create mode 100644 gas/testsuite/gas/riscv/no-relax-branch-offset-fail.l
 create mode 100644 gas/testsuite/gas/riscv/no-relax-branch-offset-fail.s
 create mode 100644 gas/testsuite/gas/riscv/no-relax-branch-offset-ok.d
 create mode 100644 gas/testsuite/gas/riscv/no-relax-branch-offset-ok.s
 create mode 100644 gas/testsuite/gas/riscv/no-relax-pcrel-offset-fail-64.d
 create mode 100644 gas/testsuite/gas/riscv/no-relax-pcrel-offset-fail-64.l
 create mode 100644 gas/testsuite/gas/riscv/no-relax-pcrel-offset-fail-64.s
 create mode 100644 gas/testsuite/gas/riscv/no-relax-pcrel-offset-fail-not-32.d
 create mode 100644 gas/testsuite/gas/riscv/no-relax-pcrel-offset-ok.d
 create mode 100644 gas/testsuite/gas/riscv/no-relax-pcrel-offset-ok.s


base-commit: 6ebd38072de4a77a2d28f04a79b64ab570532e98
-- 
2.43.0