fdcf7b694f
...while still appeasing the borrow checker by taking spillsets out of `self` and then putting them back in again when we're done. I was just doing this to enable playing with some data structures in follow up commits, but decided to benchmark this commit as-is and found 2-4% speed ups to Cranelift compilation! ``` compilation :: instructions-retired :: benchmarks/bz2/benchmark.wasm Δ = 39946528.13 ± 38398.29 (confidence = 99%) no-index.so is 1.04x to 1.04x faster than main.so! [985704952 985984130.24 986180413] main.so [945649144 946037602.11 946262076] no-index.so compilation :: instructions-retired :: benchmarks/pulldown-cmark/benchmark.wasm Δ = 48413802.56 ± 34288.05 (confidence = 99%) no-index.so is 1.03x to 1.03x faster than main.so! [1593663899 1593926801.92 1594246604] main.so [1545196678 1545512999.36 1545802144] no-index.so compilation :: instructions-retired :: benchmarks/spidermonkey/benchmark.wasm Δ = 841028066.56 ± 253404.59 (confidence = 99%) no-index.so is 1.02x to 1.02x faster than main.so! [34798712681 34801346430.28 34802786661] main.so [33958847844 33960318363.72 33962177143] no-index.so ```
regalloc2: another register allocator
This is a register allocator that started life as, and is about 50% still, a port of IonMonkey's backtracking register allocator to Rust. In many regards, it has been generalized, optimized, and improved since the initial port, and now supports both SSA and non-SSA use-cases. (However, non-SSA should be considered deprecated; we want to move to SSA-only in the future, to enable some performance improvements. See #4.)
In addition, it contains substantial amounts of testing infrastructure (fuzzing harnesses and checkers) that does not exist in the original IonMonkey allocator.
See the design overview for (much!) more detail on how the allocator works.
License
This crate is licensed under the Apache 2.0 License with LLVM
Exception. This license text can be found in the file LICENSE.
Parts of the code are derived from regalloc.rs: in particular,
src/checker.rs and src/domtree.rs. This crate has the same license
as regalloc.rs, so the license on these files does not differ.