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4721b6518c
I noticed that the Size::bits function is called in many places, and is inlined into them. On x86_64-pc-windows-msvc, this function is inlined 527 times, and compiled separately (non-inlined) 3 times. Each of those inlined calls contains code that panics. This commit moves the `panic!` call into a separate function and marks that function with `#[cold]`. This reduces binary size by 24 KB. By itself, that's not a substantial reduction. However, changes like this often reduce pressure on instruction-caches, since it reduces the amount of code that is inlined into hot code paths. Or more precisely, it removes cold code from hot cache lines. It also removes all conditionals from Size::bits(), which is called in many places. |
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| Cargo.toml | ||
| README.md | ||
librustc_target contains some very low-level details that are
specific to different compilation targets and so forth.
For more information about how rustc works, see the rustc dev guide.