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Alternative regalloc backends

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#81 2 comments 3 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
30/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
rust
Domain
compilers

Research direction

Read the regalloc2 crate API around VReg, PReg, Operand, and Function, then trace how the existing register-allocation backend is exposed. Define the scope and acceptance criteria for a fast single-pass backend, including its integration with embedders and its compilation-time versus code-quality tradeoff. Done means the backend design and integration path are agreed.

Written by the indexing model from the issue text.

Description

The regalloc2 crate provides a good API (VReg, PReg, Operand, Function, etc) for interacting with a register allocator. It would be nice if other register allocator backends could be made available with the same API to simplify integration on the embedder side.

What I specifically have in mind is a "fast" backend that simply allocates registers in a single pass with the goal of minimizing compilation time. This will have a huge impact on compilation time since my compiler spends 80% of its time in register allocation. In practice I expect to use this for a tiering JIT where hot code can later be re-compiled using the slow regalloc backend that produces better code.

Dominant language
Rust
Stars
266
Forks
54
PR merge metrics
No merged PRs in 30d

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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