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authorMarvin Borner2021-03-26 21:55:50 +0100
committerMarvin Borner2021-03-26 22:02:20 +0100
commit05498860e8f7b1e8bb27880bc7526de026694804 (patch)
tree3bddf16e9439a950a3810d45e42a5cefdbcb7663 /libc/mem.c
parenta96e9c4c858d47f61b89d879aa0ce6a02bdacb38 (diff)
Renamed libs
Cleaner and more flexible.
Diffstat (limited to 'libc/mem.c')
-rw-r--r--libc/mem.c121
1 files changed, 0 insertions, 121 deletions
diff --git a/libc/mem.c b/libc/mem.c
deleted file mode 100644
index 95242e4..0000000
--- a/libc/mem.c
+++ /dev/null
@@ -1,121 +0,0 @@
-// MIT License, Copyright (c) 2020 Marvin Borner
-
-#include <assert.h>
-#include <def.h>
-#include <mem.h>
-#include <sys.h>
-
-void *memcpy(void *dest, const void *src, u32 n)
-{
-#ifdef userspace
- // Inspired by Jeko at osdev
- u8 *dest_byte = dest;
- const u8 *src_byte = src;
- for (u32 i = 0; i < n / 16; i++) {
- __asm__ volatile("movups (%0), %%xmm0\n"
- "movntdq %%xmm0, (%1)\n" ::"r"(src_byte),
- "r"(dest_byte)
- : "memory");
-
- src_byte += 16;
- dest_byte += 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_byte), "2"((long)src_byte)
- : "memory");
- }
- return dest_byte;
-#else
- // Inspired by jgraef at osdev
- u32 num_dwords = n / 4;
- u32 num_bytes = n % 4;
- u32 *dest32 = (u32 *)dest;
- const u32 *src32 = (const u32 *)src;
- u8 *dest8 = ((u8 *)dest) + num_dwords * 4;
- const u8 *src8 = ((const u8 *)src) + num_dwords * 4;
-
- // 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)
-{
- u32 uval = val;
- u32 num_dwords = n / 4;
- u32 num_bytes = n % 4;
- u32 *dest32 = (u32 *)dest;
- u8 *dest8 = ((u8 *)dest) + num_dwords * 4;
- u8 val8 = (u8)val;
- u32 val32 = uval | (uval << 8) | (uval << 16) | (uval << 24);
-
- // 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;
-}
-
-void *memchr(void *src, int c, u32 n)
-{
- u8 *s = (u8 *)src;
-
- while (n-- > 0) {
- if (*s == c)
- return s;
- s++;
- }
- return NULL;
-}
-
-int memcmp(const void *s1, const void *s2, u32 n)
-{
- const u8 *a = (const u8 *)s1;
- const u8 *b = (const u8 *)s2;
- for (u32 i = 0; i < n; i++) {
- if (a[i] < b[i])
- return -1;
- else if (b[i] < a[i])
- return 1;
- }
- return 0;
-}
-
-int mememp(const u8 *buf, u32 n)
-{
- return buf[0] == 0 && !memcmp(buf, buf + 1, n - 1);
-}