cosmopolitan/libc/str/djbsort.c
Gautham 6f658f058b
Change noinline to dontinline (#312)
We defined `noinline` as an abbreviation for the longer version
`__attribute__((__noinline__))` which caused name clashes since
third party codebases often write it as `__attribute__((noinline))`.
2021-11-12 15:12:18 -08:00

71 lines
2.9 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/alg/alg.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/nexgen32e/bsr.h"
#include "libc/nexgen32e/nexgen32e.h"
#include "libc/nexgen32e/x86feature.h"
void djbsort_avx2(int32_t *, long);
static dontinline void intsort(int *x, size_t n, size_t t) {
int a, b, c;
size_t i, p, q;
for (p = t; p > 0; p >>= 1) {
for (i = 0; i < n - p; ++i) {
if (!(i & p)) {
a = x[i + 0];
b = x[i + p];
if (a > b) c = a, a = b, b = c;
x[i + 0] = a;
x[i + p] = b;
}
}
for (q = t; q > p; q >>= 1) {
for (i = 0; i < n - q; ++i) {
if (!(i & p)) {
a = x[i + p];
b = x[i + q];
if (a > b) c = a, a = b, b = c;
x[i + p] = a;
x[i + q] = b;
}
}
}
}
}
/**
* D.J. Bernstein's outrageously fast integer sorting algorithm.
*/
void djbsort(int32_t *a, size_t n) {
size_t m;
if (IsAsan()) {
if (__builtin_mul_overflow(n, 4, &m)) m = -1;
__asan_verify(a, m);
}
if (n > 1) {
if (X86_HAVE(AVX2)) {
djbsort_avx2(a, n);
} else {
intsort(a, n, 1ul << bsrl(n - 1));
}
}
}