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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
commit | 698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch) | |
tree | 173a775858bd501c378080a10dca74132f05bc50 /vendor/serde_json/src/lexical/shift.rs | |
parent | Initial commit. (diff) | |
download | rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip |
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | vendor/serde_json/src/lexical/shift.rs | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/vendor/serde_json/src/lexical/shift.rs b/vendor/serde_json/src/lexical/shift.rs new file mode 100644 index 000000000..a0bae01e0 --- /dev/null +++ b/vendor/serde_json/src/lexical/shift.rs @@ -0,0 +1,46 @@ +// Adapted from https://github.com/Alexhuszagh/rust-lexical. + +//! Bit-shift helpers. + +use super::float::ExtendedFloat; +use core::mem; + +// Shift extended-precision float right `shift` bytes. +#[inline] +pub(crate) fn shr(fp: &mut ExtendedFloat, shift: i32) { + let bits: u64 = mem::size_of::<u64>() as u64 * 8; + debug_assert!((shift as u64) < bits, "shr() overflow in shift right."); + + fp.mant >>= shift; + fp.exp += shift; +} + +// Shift extended-precision float right `shift` bytes. +// +// Accepts when the shift is the same as the type size, and +// sets the value to 0. +#[inline] +pub(crate) fn overflowing_shr(fp: &mut ExtendedFloat, shift: i32) { + let bits: u64 = mem::size_of::<u64>() as u64 * 8; + debug_assert!( + (shift as u64) <= bits, + "overflowing_shr() overflow in shift right." + ); + + fp.mant = if shift as u64 == bits { + 0 + } else { + fp.mant >> shift + }; + fp.exp += shift; +} + +// Shift extended-precision float left `shift` bytes. +#[inline] +pub(crate) fn shl(fp: &mut ExtendedFloat, shift: i32) { + let bits: u64 = mem::size_of::<u64>() as u64 * 8; + debug_assert!((shift as u64) < bits, "shl() overflow in shift left."); + + fp.mant <<= shift; + fp.exp -= shift; +} |