[Merged by Bors] - Avoid unneeded bounds checks in bytecode address patching #2680
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Test262 conformance changes
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Codecov Report
@@ Coverage Diff @@
## main #2680 +/- ##
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+ Coverage 49.19% 49.41% +0.22%
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Files 397 395 -2
Lines 39739 39531 -208
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- Hits 19548 19533 -15
+ Misses 20191 19998 -193
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Got it to optimize the bounds check without using unsafe: https://godbolt.org/z/9eEs13TjW EDIT: Another alternative that clarifies why the second condition is needed: const U32_SIZE: usize = std::mem::size_of::<u32>();
assert!(code.len() > index + U32_SIZE && usize::MAX - U32_SIZE >= index);
let values = value.to_ne_bytes();
code[index..index + U32_SIZE].copy_from_slice(values.as_slice()) |
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As discussed in this comment #2669 (comment), `rustc` doesn't seem to optimize out the bounds checks.
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As discussed in this comment #2669 (comment),
rustcdoesn't seem to optimize out the bounds checks.