[RFC PATCH v2 0/2] RISC-V: Add support for the Zfa extension

[Christoph Muellner <christoph.muellner@vrull.eu>]

From: Christoph Müllner <christoph.muellner@vrull.eu>

This series adds support for the RISC-V Zfa extension.
It consists of two patches:
1) A clean-up patch from Tsukasa that improves the way we structure
   format string directives.
2) A patch that introduces support for the Zfa extension.

The first patch does not have any dependencies and is suggested to get
merged as early as possible.

The second patch can land once the Zfa specification gets frozen.

Some additional bits to get the full context:
* Tsukasa wrote a first version, which can be found here:
  https://sourceware.org/pipermail/binutils/2022-September/122939.html
* I took over the patch as agreed here:
  https://sourceware.org/pipermail/binutils/2023-March/126753.html

There is also a discussion how to represent the constants in the
assembly notation. I've decided to use C-like constants, as I consider
this as the most user-friedly form for assembly programmers (for
examples see gas/testsuite/gas/riscv/zfa.s).
I prefer to not support the RS1-constants or the hex-encoded register
values that will land in the floating-point registers, as I want to
avoid misinterpretation because of multiple allowed notations.
If another notation is preferred, then please let me know.

Christoph Müllner (1):
  RISC-V: Add support for the Zfa extension

Tsukasa OI (1):
  RISC-V: Allocate "various" operand type

 bfd/elfxx-riscv.c                  | 39 ++++++++++++
 gas/config/tc-riscv.c              | 89 ++++++++++++++++++++++-----
 gas/testsuite/gas/riscv/zfa-32.d   | 10 +++
 gas/testsuite/gas/riscv/zfa-32.s   |  3 +
 gas/testsuite/gas/riscv/zfa-64.d   | 10 +++
 gas/testsuite/gas/riscv/zfa-64.s   |  3 +
 gas/testsuite/gas/riscv/zfa-fail.d |  2 +
 gas/testsuite/gas/riscv/zfa-fail.l | 33 ++++++++++
 gas/testsuite/gas/riscv/zfa-fail.s | 26 ++++++++
 gas/testsuite/gas/riscv/zfa.d      | 89 +++++++++++++++++++++++++++
 gas/testsuite/gas/riscv/zfa.s      | 87 ++++++++++++++++++++++++++
 include/opcode/riscv-opc.h         | 99 ++++++++++++++++++++++++++++++
 include/opcode/riscv.h             |  5 ++
 opcodes/riscv-dis.c                | 38 ++++++++++--
 opcodes/riscv-opc.c                | 59 +++++++++++++++++-
 15 files changed, 567 insertions(+), 25 deletions(-)
 create mode 100644 gas/testsuite/gas/riscv/zfa-32.d
 create mode 100644 gas/testsuite/gas/riscv/zfa-32.s
 create mode 100644 gas/testsuite/gas/riscv/zfa-64.d
 create mode 100644 gas/testsuite/gas/riscv/zfa-64.s
 create mode 100644 gas/testsuite/gas/riscv/zfa-fail.d
 create mode 100644 gas/testsuite/gas/riscv/zfa-fail.l
 create mode 100644 gas/testsuite/gas/riscv/zfa-fail.s
 create mode 100644 gas/testsuite/gas/riscv/zfa.d
 create mode 100644 gas/testsuite/gas/riscv/zfa.s

-- 
2.39.2