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47a4913834
* [vcpkg] Correct UInt128 code 😇
`UInt128::operator<<(x, y)` should clear the bottom 64 bits of `x` if
`y >= 64`; however, we don't do this, and so we duplicate `x`'s bottom
bits into `x.top` instead of moving them. Similarly, we have the
opposite problem for `UInt128::operator>>`. This commit fixes these
latent bugs, which we weren't hitting because the thing we use them for
never actually shifts more than 64 bits.
27 lines
487 B
C++
27 lines
487 B
C++
#pragma once
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#include <stdint.h>
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namespace vcpkg {
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struct UInt128 {
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UInt128() = default;
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UInt128(uint64_t value) : bottom(value), top(0) {}
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UInt128& operator<<=(int by) noexcept;
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UInt128& operator>>=(int by) noexcept;
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UInt128& operator+=(uint64_t lhs) noexcept;
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uint64_t bottom_64_bits() const noexcept {
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return bottom;
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}
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uint64_t top_64_bits() const noexcept {
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return top;
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}
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private:
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uint64_t bottom;
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uint64_t top;
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};
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}
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