Stream: git-wasmtime

Topic: wasmtime / PR #7871 x64: Refactor multiplication instruct...

Wasmtime GitHub notifications bot (Feb 05 2024 at 17:44):

alexcrichton opened PR #7871 from alexcrichton:x64-mul to bytecodealliance:main:

This commit is inspired after reading over some code from #7865 and #7866. The goal of this commit was to refactor scalar multiplication-related instructions in the x64 backend to more closely align with their native instructions. Changes include:

• The MulHi instruction is renamed to Mul. This represents either mul or imul producing a doublewide result.
• A Mul8 instruction was added to correspond to Mul for the 8-bit variants that produce a doublewide result in the AX register rather than the other instructions which split between RAX and RDX.
• The UMulLo instruction was removed as now it's covered by Mul
• The AluRmiROpcode::Mul opcode was removed in favor of new IMul and IMulImm instructions. Register allocation and emission already had special cases for Mul which felt better as standalone instructions rather than putting in an existing variant.

Lowerings using imul are not affected in general but the IMulImm instruction has different register allocation behavior than before which allows the destination to have a different register than the first operand. The umulhi and smulhi instructions are also reimplemented with their 8-bit variants instead of extension-plus-16-bit variants.

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Wasmtime GitHub notifications bot (Feb 05 2024 at 17:44):

alexcrichton requested abrown for a review on PR #7871.

Wasmtime GitHub notifications bot (Feb 05 2024 at 17:44):

alexcrichton requested wasmtime-compiler-reviewers for a review on PR #7871.

Wasmtime GitHub notifications bot (Feb 06 2024 at 22:49):

fitzgen submitted PR review:

Nice!

Wasmtime GitHub notifications bot (Feb 06 2024 at 22:49):

fitzgen has enabled auto merge for PR #7871.

Wasmtime GitHub notifications bot (Feb 06 2024 at 22:49):

fitzgen has disabled auto merge for PR #7871.

Wasmtime GitHub notifications bot (Feb 09 2024 at 11:05):

alexcrichton updated PR #7871.

Wasmtime GitHub notifications bot (Feb 09 2024 at 11:14):

alexcrichton commented on PR #7871:

cc @abrown you mentioned that you were also taking a look at this, want me to hold off on merging for that?

Wasmtime GitHub notifications bot (Feb 09 2024 at 11:18):

alexcrichton updated PR #7871.

Wasmtime GitHub notifications bot (Feb 09 2024 at 12:47):

github-actions[bot] commented on PR #7871:

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Wasmtime GitHub notifications bot (Feb 09 2024 at 22:44):

abrown commented on PR #7871:

Nah, it's good to go now that @fitzgen looked at it.

Wasmtime GitHub notifications bot (Feb 09 2024 at 23:13):

abrown merged PR #7871.

Last updated: Dec 23 2024 at 12:05 UTC