cosmopolitan/test/libc/str/memcmp_test.c
2021-09-06 19:24:10 -07:00

74 lines
3.5 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 2021 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/rand/rand.h"
#include "libc/str/str.h"
#include "libc/testlib/ezbench.h"
#include "libc/testlib/fastrandomstring.h"
#include "libc/testlib/testlib.h"
int unfancy_memcmp(const void *a, const void *b, size_t n) {
int c;
size_t i;
const unsigned char *x, *y;
for (x = a, y = b, i = 0; i < n; ++i) {
if ((c = x[i] - y[i])) {
return c;
}
}
return 0;
}
TEST(memcmp, test) {
EXPECT_EQ(0, memcmp("hi", "hi", 2));
EXPECT_NE(0, memcmp("hi", "HI", 2));
EXPECT_EQ(-1, memcmp("a", "b", 1));
EXPECT_EQ(+1, memcmp("b", "a", 1));
}
TEST(memcmp, fuzz) {
int i, n;
char a[32], b[32];
for (i = 0; i < 1000; ++i) {
n = rand() & 31;
rngset(a, n, rand64, -1);
rngset(b, n, rand64, -1);
ASSERT_EQ(unfancy_memcmp(a, b, n), memcmp(a, b, n), "n=%d", n);
}
}
BENCH(memcmp, bench) {
extern int funcmp(const void *a, const void *b, size_t n) asm("memcmp");
volatile int v;
const char *volatile a;
const char *volatile b;
b = a = "123456789123456789123456789123456789123456789123456789";
EZBENCH2("memcmp same", donothing, v = funcmp(a, b, 7));
b = gc(strdup(b));
EZBENCH2("memcmp 1", donothing, v = funcmp(a, b, 1));
EZBENCH2("memcmp 2", donothing, v = funcmp(a, b, 2));
EZBENCH2("memcmp 3", donothing, v = funcmp(a, b, 3));
EZBENCH2("memcmp 4", donothing, v = funcmp(a, b, 4));
EZBENCH2("memcmp 5", donothing, v = funcmp(a, b, 5));
EZBENCH2("memcmp 6", donothing, v = funcmp(a, b, 6));
EZBENCH2("memcmp 7", donothing, v = funcmp(a, b, 7));
EZBENCH2("memcmp 8", donothing, v = funcmp(a, b, 8));
EZBENCH2("memcmp 9", donothing, v = funcmp(a, b, 9));
EZBENCH2("memcmp 16", donothing, v = funcmp(a, b, 16));
EZBENCH2("memcmp 32", donothing, v = funcmp(a, b, 32));
}