Work around crash on Intel Raptor Lake CPU

[glandium]

Fixes #306

[folkertdev]

It looks like the most recent LLVM already works around this, see https://godbolt.org/z/8noxnTWe9.

How does that factor into your process? I understand people build from source, but mostly Mozilla distributes the builds I think, so you could use the more recent compiler. Does patching for earlier rustc versions still make sense?

[glandium]

Notwithstanding the fact that as of now Mozilla is building with Rustc 1.92, downstreams have a broad range of rust compiler versions they may use.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

Flag	Coverage Δ
fuzz-compress	?
fuzz-decompress	?
test-aarch64-apple-darwin	87.91% <100.00%> (-0.02%)	⬇️
test-aarch64-unknown-linux-gnu	85.31% <100.00%> (-0.02%)	⬇️
test-i686-unknown-linux-gnu	85.00% <100.00%> (-0.02%)	⬇️
test-x86_64-apple-darwin	88.26% <100.00%> (+0.01%)	⬆️
test-x86_64-unknown-linux-gnu	89.90% <100.00%> (-2.73%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
zlib-rs/src/deflate/sym_buf.rs	97.56% <100.00%> (-0.12%)	⬇️

... and 4 files with indirect coverage changes

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[folkertdev]

Sure, makes sense.

I noticed that we should really use [u8; 3] here now, but I'll play around with that in #522 and preserve the codegen (i.e. lack of movb %ch) there.