Stream: git-wasmtime

Topic: wasmtime / PR #11270 x64: Add EVEX shifts to the new asse...

Wasmtime GitHub notifications bot (Jul 17 2025 at 20:03):

alexcrichton requested abrown for a review on PR #11270.

Wasmtime GitHub notifications bot (Jul 17 2025 at 20:03):

alexcrichton opened PR #11270 from alexcrichton:x64-evex-shift to bytecodealliance:main:

This commit adds bindings for the EVEX encodings of vps{ll,ra,rl}{d,q} to the new assembler. Currently the 16-bit shifts vps{ll,ra,rl}w are omitted due to the avx512bw feature not yet being bound in Cranelift. In implementing these instructions a few refactorings/fixes were necessary:

• Primarily all EVEX instructions now need to be defined not only with their vector length but also their "tuple type" found in encoding tables. This is required to correctly handle the 8-bit displacement scaling that happens with EVEX instructions.
• Some small helpers to the Evex structure were added such as Evex::digit and Evex::ib.
• The evex_scaling factor is now calculated in generate_evex_prefix according to the instruction format itself.
• The VEX and EVEX generate_*_prefix functions now delegate to a shared function to handle the same operand formats across both of them.
• Fuzz generation of AmodeOffset is now updated to bias to some "interesting" offsets that exercise the cases where EVEX scaling is necessary.
• The ISLE XmmUnaryRmRImmEvex instruction format was removed as it's no longer necessary.

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Wasmtime GitHub notifications bot (Jul 17 2025 at 20:03):

alexcrichton requested wasmtime-compiler-reviewers for a review on PR #11270.

Wasmtime GitHub notifications bot (Jul 17 2025 at 20:24):

alexcrichton updated PR #11270.

Wasmtime GitHub notifications bot (Jul 17 2025 at 23:30):

abrown submitted PR review.

Wasmtime GitHub notifications bot (Jul 17 2025 at 23:55):

abrown merged PR #11270.

Last updated: Dec 06 2025 at 06:05 UTC