AMDGPU should implement TargetInstrInfo::isSubregFoldable
Open
backend:AMDGPU
llvm:regalloc
missed-optimization
- Dominant language
- LLVM
- Stars
- 40.5k
- Forks
- 18.7k
- PR merge metrics
- PR metrics pending
Description
AMDGPU should implement isSubregFoldable to support folding subregister extracts into spills. This will need supported code in foldMemoryOperandImpl to rewrite the spill instruction to only sill the subregister
Contributor guide
Research direction
Start by tracing AMDGPU's TargetInstrInfo::isSubregFoldable entry point and the foldMemoryOperandImpl path mentioned in the issue. Compare the existing spill-folding behavior and verify that subregister extracts can be folded into spills, with the spill instruction rewritten to store only the subregister.
Written by the indexing model from the issue text.
Assessment
- Domain
- compilers
- Issue type
- Feature
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100