diff options
Diffstat (limited to 'libc/mem.c')
| -rw-r--r-- | libc/mem.c | 65 |
1 files changed, 54 insertions, 11 deletions
@@ -5,24 +5,61 @@ #include <mem.h> #include <sys.h> -// Taken from jgraef at osdev void *memcpy(void *dest, const void *src, u32 n) { +#ifdef userspace + // Inspired by Jeko at osdev + for (u32 i = 0; i < n / 16; i++) { + __asm__ __volatile__("movups (%0), %%xmm0\n" + "movntdq %%xmm0, (%1)\n" ::"r"(src), + "r"(dest) + : "memory"); + + src = ((u8 *)src) + 16; + dest = ((u8 *)dest) + 16; + } + + if (n & 7) { + n = n & 7; + + int d0, d1, d2; + __asm__ __volatile__("rep ; movsl\n\t" + "testb $2,%b4\n\t" + "je 1f\n\t" + "movsw\n" + "1:\ttestb $1,%b4\n\t" + "je 2f\n\t" + "movsb\n" + "2:" + : "=&c"(d0), "=&D"(d1), "=&S"(d2) + : "0"(n / 4), "q"(n), "1"((long)dest), "2"((long)src) + : "memory"); + } + return dest; +#else + // Inspired by jgraef at osdev u32 num_dwords = n / 4; u32 num_bytes = n % 4; u32 *dest32 = (u32 *)dest; u32 *src32 = (u32 *)src; u8 *dest8 = ((u8 *)dest) + num_dwords * 4; u8 *src8 = ((u8 *)src) + num_dwords * 4; - u32 i; - for (i = 0; i < num_dwords; i++) { - dest32[i] = src32[i]; - } - for (i = 0; i < num_bytes; i++) { + // TODO: What's faster? + __asm__ volatile("rep movsl\n" + : "=S"(src32), "=D"(dest32), "=c"(num_dwords) + : "S"(src32), "D"(dest32), "c"(num_dwords) + : "memory"); + + /* for (u32 i = 0; i < num_dwords; i++) { */ + /* dest32[i] = src32[i]; */ + /* } */ + + for (u32 i = 0; i < num_bytes; i++) { dest8[i] = src8[i]; } return dest; +#endif } void *memset(void *dest, int val, u32 n) @@ -33,12 +70,18 @@ void *memset(void *dest, int val, u32 n) u8 *dest8 = ((u8 *)dest) + num_dwords * 4; u8 val8 = (u8)val; u32 val32 = val | (val << 8) | (val << 16) | (val << 24); - u32 i; - for (i = 0; i < num_dwords; i++) { - dest32[i] = val32; - } - for (i = 0; i < num_bytes; i++) { + // TODO: What's faster? + __asm__ volatile("rep stosl\n" + : "=D"(dest32), "=c"(num_dwords) + : "D"(dest32), "c"(num_dwords), "a"(val32) + : "memory"); + + /* for (u32 i = 0; i < num_dwords; i++) { */ + /* dest32[i] = val32; */ + /* } */ + + for (u32 i = 0; i < num_bytes; i++) { dest8[i] = val8; } return dest; |