Tracking Issue for APX target feature

[sayantn]

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:
  • Added support for apxf target feature #139534
• 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

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩

[madhav-madhusoodanan]

Hi, would it be okay if I take a shot at this?
Wanted to learn the nuances behind implementing an x86-64 specific target feature.

[sayantn]

Sure, No problems! See this zulip link for more info on the topic. You can also contact me anytime on Zulip 🥰. Also you can see some of my recent PRs for info on how to add a target feature (e.g #138003)

[rustbot]

Unknown labels: O-x86-64