Stream: git-wasmtime

Topic: wasmtime / PR #1674 MachInst backend: don't reallocate Re...

Wasmtime GitHub notifications bot (May 08 2020 at 22:37):

cfallin requested bnjbvr and julian-seward1 for a review on PR #1674.

Wasmtime GitHub notifications bot (May 08 2020 at 22:37):

cfallin opened PR #1674 from machinst-reg-universe-opt to master:

There's no good reason for the current behavior; we just happened to build the RealRegUniverse each time it was needed. This involves allocating a Vec and pushing a bunch (on AArch64, O(64)) of register-info structs onto it. We should share this work across the backend instance as long as it exists; and we can, because the flags (which might affect which registers we use) remain constant for one backend instance.

This saves ~0.14% instruction count, ~0.18% allocated bytes, and ~1.5%
allocated blocks on a clif-util wasm compilation of bz2.wasm for
aarch64.

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Wasmtime GitHub notifications bot (May 08 2020 at 22:37):

cfallin requested bnjbvr and julian-seward1 for a review on PR #1674.

Wasmtime GitHub notifications bot (May 09 2020 at 06:04):

julian-seward1 submitted PR Review.

Wasmtime GitHub notifications bot (May 09 2020 at 21:10):

cfallin merged PR #1674.

Last updated: Dec 06 2025 at 06:05 UTC