Tracking Issue for APX target feature
Nobody has claimed this yet.
- Dominant language
- Rust
- Stars
- 119k
- Forks
- 16.1k
- PR merge metrics
- PR metrics pending
Description
The feature gate for the issue is #![feature(apx_target_feature)].
Advanced Performance Extensions is a general-purpose extension of x86-64 for all Intel CPUs. See this presentation by LLVM team for more info about this.
Public API
The apxf target feature, and usage of GPR32 in inline ASM
Steps / History
- Implementation:
- #139534
- #145531
- Final comment period (FCP)^1
- Stabilization PR
Unresolved Questions
- How to handle
inline-asm-use-gpr32? The GPR32 registers (specifically REX2) can't be used with VEX encoded instructions, notably AVX and SSE. See the GCC patch for more info
@rustbot label O-x86_64 A-target-feature A-inline-assembly T-compiler -T-libs-api
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reading implementation issues #139534 and #145531, then review the linked LLVM presentation and GCC patch for APX and GPR32 constraints. The work is done when the implementation is complete, the inline-asm-use-gpr32 question is resolved, the final comment period finishes, and a stabilization PR is prepared.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- compilers
- Issue type
- Feature
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 25/100