[all-commits] [llvm/llvm-project] c4b591: [Flang][RISCV] Set vscale_range based off zvl*b (#...

[Luke Lau via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: c4b591a10f2f604291da14aea7983a5fa7837ce8
      https://github.com/llvm/llvm-project/commit/c4b591a10f2f604291da14aea7983a5fa7837ce8
  Author: Luke Lau <luke at igalia.com>
  Date:   2024-01-15 (Mon, 15 Jan 2024)

  Changed paths:
    M flang/lib/Frontend/FrontendActions.cpp
    M flang/test/Lower/RISCV/riscv-vector-bits-vscale-range.f90

  Log Message:
  -----------
  [Flang][RISCV] Set vscale_range based off zvl*b (#77277)

This patch implements the logic (for now, copied from
RISCVTargetInfo::getVScaleRange) so that we can compute the vscale_range
based off of the zvl*b extension, e.g. using an arch with zvl256b now
implies vscale_range(2,1024).

It's worth noting that we don't have to exactly copy the behaviour of
clang with regards to how it interacts with the
-mvscale-min/-mvscale-max flags, but changing it can be left to a future
patch.

This also adds a guard for +sve so that we only check for it on aarch64,
which was the behaviour prior to 898db1136e679