Similar to 806761a7629df268c8aed49657aeccffa6bca449.
For IR files without a target triple, -mtriple= specifies the full
target triple while -march= merely sets the architecture part of the
default target triple, leaving a target triple which may not make sense,
e.g. amdgpu-apple-darwin.
Therefore, -march= is error-prone and not recommended for tests without
a target triple. The issue has been benign as we recognize
$unknown-apple-darwin as ELF instead of rejecting it outrightly.
This patch changes AMDGPU tests to not rely on the default
OS/environment components. Tests that need fixes are not changed:
```
LLVM :: CodeGen/AMDGPU/fabs.f64.ll
LLVM :: CodeGen/AMDGPU/fabs.ll
LLVM :: CodeGen/AMDGPU/floor.ll
LLVM :: CodeGen/AMDGPU/fneg-fabs.f64.ll
LLVM :: CodeGen/AMDGPU/fneg-fabs.ll
LLVM :: CodeGen/AMDGPU/r600-infinite-loop-bug-while-reorganizing-vector.ll
LLVM :: CodeGen/AMDGPU/schedule-if-2.ll
```
After D133067 we are inserting swaps to use a new physical
register. I have noticed verifier errors about undefined
physical register uses if we are tracking liveness post RA.
We have no access to LIS at this point, so mark new register
uses as undef to calm down the verifier. Liveness should not
matter at this point anyway.
Note the description of the RegState::Undef: "Value of the
register doesn't matter." I.e. it does not say it is strictly
undefined. In fact that is what we really need: this value
does not matter.
I also had to modify the test a bit since with tracking enabled
it does not pass verification even before the recognizer.
Differential Revision: https://reviews.llvm.org/D133459
In this case gfx90a uses v0 instead of the correct register. Swap
the value temporarily with a lower register and then swap it back.
Unfortunately hazard recognizer works after wait count insertion,
so we cannot simply reuse an arbitrary register, hence w/a also
includes a full waitcount. This can be avoided if we run it from
expandPostRAPseudo, but that is a complete misplacement.
Differential Revision: https://reviews.llvm.org/D133067
