Simplify some shift casting #186
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This is in preparation for bumping the lint set, which will include `clippy::cast_possible_wrap`. For the fallback code using `Shl`, we don't need to cast as `Shl` is implemented for all scalar types as shift argument. Casting versus calling directly compile to the same thing: https://godbolt.org/z/6G9bvYdjd. For the x86 code, we cast from `u32` to `i32`, so we can use `u32::cast_signed` for that, which explicitly is a no-op and has the overflow behavior that's probably expected here.
LaurenzV
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Jan 23, 2026
tomcur
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Missed this in linebender#186.
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Missed this in #186.
tomcur
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Like linebender#186, explicitly reinterpret the bit patterns as signed (i.e., this is explicitly a no-op at the instruction-level). Also uses `cast_signed` for splatting on x86, which just broadcasts the bit pattern. Fixes the remainder of `clippy::cast_possible_wrap` warnings on x86.
tomcur
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Like linebender#186, explicitly reinterpret the bit patterns as signed (i.e., this is explicitly a no-op at the instruction-level). Also uses `cast_signed` for splatting on x86, which just broadcasts the bit pattern. Fixes the remainder of `clippy::cast_possible_wrap` warnings on x86.
tomcur
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Jan 25, 2026
Like linebender#186, explicitly reinterpret the bit patterns as signed (i.e., this is explicitly a no-op at the instruction-level). Also uses `cast_signed` for splatting on x86, which just broadcasts the bit pattern. Fixes the remainder of `clippy::cast_possible_wrap` warnings on x86.
tomcur
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Jan 25, 2026
Like linebender#186, explicitly reinterpret the bit patterns as signed (i.e., this is explicitly a no-op at the instruction-level). Also uses `cast_signed` for splatting on x86, which just broadcasts the bit pattern. Fixes the remainder of `clippy::cast_possible_wrap` warnings on x86.
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This fixes the remainder of `clippy::cast_possible_wrap` warnings on x86. Very similarly to #186, explicitly reinterpret these bit patterns as signed (i.e., this again is explicitly a no-op at the instruction-level, but effectively checks bit width remains the same). Also uses `cast_signed` for splatting on x86, which just takes the bit pattern as a signed numeric type for broadcasting.
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This is in preparation for bumping the lint set, which will include
clippy::cast_possible_wrap.For the fallback code using
Shl, we don't need to cast asShlis implemented for all scalar types as shift argument. Casting versus calling directly compile to the same thing:https://godbolt.org/z/6G9bvYdjd.
For the x86 code, we cast from
u32toi32, so we can useu32::cast_signedfor that, which explicitly stays at the same bit width and has the sign behavior that's probably expected here.