Join GitHub today
GitHub is home to over 28 million developers working together to host and review code, manage projects, and build software together.Sign up
Use a faster `deflate` setting #37298
In #37086 we have considered various ideas for reducing the cost of LLVM bytecode compression. This PR implements the simplest of these: use a faster
I looked at using zstd, which might be able to halve the compression time again. But integrating zstd is beyond my Rust FFI integration abilities at the moment -- it consists of a few dozen C files, has a non-trivial build system, etc. I decided it was worth getting a big chunk of the possible improvement with minimum effort.
The following table shows the before and after percentages of instructions executed during compression while doing debug builds of some of the rustc-benchmarks with a stage1 compiler.
The omitted ones spend 0% of their time in decompression.
And here are actual timings: