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Perform some code cleanup

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This commit is contained in:
Justine Tunney 2023-05-15 16:32:10 -07:00
parent cc1732bc42
commit 210187cf77
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GPG key ID: BE714B4575D6E328
205 changed files with 1748 additions and 2595 deletions
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42
libc/intrin/bsf.c
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@ -38,3 +38,45 @@
int(_bsf)(int x) {
return _bsf(x);
}
/**
* Returns position of first bit set.
*
* ctz(𝑥) 31^clz(𝑥) clz(𝑥)
* uint32 𝑥 _bsf(𝑥) tzcnt(𝑥) ffs(𝑥) _bsr(𝑥) lzcnt(𝑥)
* 0x00000000 wut 32 0 wut 32
* 0x00000001 0 0 1 0 31
* 0x80000001 0 0 1 31 0
* 0x80000000 31 31 32 31 0
* 0x00000010 4 4 5 4 27
* 0x08000010 4 4 5 27 4
* 0x08000000 27 27 28 27 4
* 0xffffffff 0 0 1 31 0
*
* @param 𝑥 is a 64-bit integer
* @return number in range 0..63 or undefined if 𝑥 is 0
*/
int(_bsfl)(long x) {
return _bsfl(x);
}
/**
* Returns position of first bit set.
*
* ctz(𝑥) 31^clz(𝑥) clz(𝑥)
* uint32 𝑥 _bsf(𝑥) tzcnt(𝑥) ffs(𝑥) _bsr(𝑥) lzcnt(𝑥)
* 0x00000000 wut 32 0 wut 32
* 0x00000001 0 0 1 0 31
* 0x80000001 0 0 1 31 0
* 0x80000000 31 31 32 31 0
* 0x00000010 4 4 5 4 27
* 0x08000010 4 4 5 27 4
* 0x08000000 27 27 28 27 4
* 0xffffffff 0 0 1 31 0
*
* @param 𝑥 is a 64-bit integer
* @return number in range 0..63 or undefined if 𝑥 is 0
*/
int(_bsfll)(long long x) {
return _bsfll(x);
}