[all-commits] [llvm/llvm-project] bbef38: Revert "[LowerTypeTests] Support generating Armv6-...

[Simon Tatham via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: bbef38352fbade9e014ec97d5991da5dee306da7
      https://github.com/llvm/llvm-project/commit/bbef38352fbade9e014ec97d5991da5dee306da7
  Author: Simon Tatham <simon.tatham at arm.com>
  Date:   2023-02-16 (Thu, 16 Feb 2023)

  Changed paths:
    M llvm/include/llvm/Analysis/TargetTransformInfo.h
    M llvm/include/llvm/Analysis/TargetTransformInfoImpl.h
    M llvm/lib/Analysis/TargetTransformInfo.cpp
    M llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp
    M llvm/lib/Target/ARM/ARMTargetTransformInfo.h
    M llvm/lib/Transforms/IPO/LowerTypeTests.cpp
    M llvm/test/Transforms/LowerTypeTests/function-arm-thumb.ll
    M llvm/test/Transforms/LowerTypeTests/function.ll

  Log Message:
  -----------
  Revert "[LowerTypeTests] Support generating Armv6-M jump tables."

This reverts commit f6ddf7781471b71243fa3c3ae7c93073f95c7dff.

Eight buildbots reported that the two test files changed by that
commit had started failing. The buildbots in question all had in
common that they build with a very restricted `LLVM_TARGETS_TO_BUILD`,
such as only X86 or AArch64 or Hexagon. I didn't notice this before
commit because my own build has the full default set of targets, and
in that circumstance, the tests pass.

I assume the problem has something to do with the attempt to query
TargetTransformInfo: if you can't make a valid TTI for the target
triple then you can't ask it what kind of inline assembler you should
be emitting, and so `opt` without the Arm backend can't get the Arm
cases of these tests right.

I don't have time to fix this until next week, so I'll revert the
change for now to keep the buildbots happy.