Commit 5c678349 authored by Damien George's avatar Damien George
Browse files

Merge branch 'iabdalkader-memcpy'

parents bb295468 32781cce
......@@ -27,14 +27,41 @@
#include <stdint.h>
#include "std.h"
void *memcpy(void *dest, const void *src, size_t n) {
// TODO align and copy 32 bits at a time
uint8_t *d = dest;
const uint8_t *s = src;
for (; n > 0; n--) {
*d++ = *s++;
#define likely(x) __builtin_expect((x), 1)
void *memcpy(void *dst, const void *src, size_t n) {
if (likely(!(((uint32_t)dst) & 3) && !(((uint32_t)src) & 3))) {
// pointers aligned
uint32_t *d = dst;
const uint32_t *s = src;
// copy words first
for (size_t i = (n >> 2); i; i--) {
*d++ = *s++;
}
if (n & 2) {
// copy half-word
*(uint16_t*)d = *(const uint16_t*)s;
d = (uint32_t*)((uint16_t*)d + 1);
s = (const uint32_t*)((const uint16_t*)s + 1);
}
if (n & 1) {
// copy byte
*((uint8_t*)d) = *((const uint8_t*)s);
}
} else {
// unaligned access, copy bytes
uint8_t *d = dst;
const uint8_t *s = src;
for (; n; n--) {
*d++ = *s++;
}
}
return dest;
return dst;
}
void *memmove(void *dest, const void *src, size_t n) {
......@@ -53,9 +80,24 @@ void *memmove(void *dest, const void *src, size_t n) {
}
void *memset(void *s, int c, size_t n) {
uint8_t *s2 = s;
for (; n > 0; n--) {
*s2++ = c;
if (c == 0 && ((uint32_t)s & 3) == 0) {
// aligned store of 0
uint32_t *s32 = s;
for (size_t i = n >> 2; i > 0; i--) {
*s32++ = 0;
}
if (n & 2) {
*((uint16_t*)s32) = 0;
s32 = (uint32_t*)((uint16_t*)s32 + 1);
}
if (n & 1) {
*((uint8_t*)s32) = 0;
}
} else {
uint8_t *s2 = s;
for (; n > 0; n--) {
*s2++ = c;
}
}
return s;
}
......
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