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
```
Use an `OptimizationRemark` for them even though it's not really an
optimization. It just integrates better with the other diagnostics
(enabling is easy with `-pass-remark`).
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D147703
Adds a new pass that removes functions
if they use features that are not supported on the current GPU.
This change is aimed at preventing crashes when building code at O0 that
uses idioms such as `if (ISA_VERSION >= N) intrinsic_a(); else intrinsic_b();`
where ISA_VERSION is not constexpr, and intrinsic_a is not selectable
on older targets.
This is a pattern that's used all over the ROCm device libs. The main
motive behind this change is to allow code using ROCm device libs
to be built at O0.
Note: the feature checking logic is done ad-hoc in the pass. There is no other
pass that needs (or will need in the foreseeable future) to do similar
feature-checking logic so I did not see a need to generalize the feature
checking logic yet. It can (and should probably) be generalized later and
moved to a TargetInfo-like class or helper file.
Reviewed By: arsenm, Joe_Nash
Differential Revision: https://reviews.llvm.org/D139000
