| 35,116 → 35,13 |
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| #ifndef KERN_ia32_MEMSTR_H_ |
| #define KERN_ia32_MEMSTR_H_ |
| |
| /** Copy memory |
| * |
| * Copy a given number of bytes (3rd argument) |
| * from the memory location defined by 2nd argument |
| * to the memory location defined by 1st argument. |
| * The memory areas cannot overlap. |
| * |
| * @param dst Destination |
| * @param src Source |
| * @param cnt Number of bytes |
| * @return Destination |
| */ |
| static inline void * memcpy(void * dst, const void * src, size_t cnt) |
| { |
| unative_t d0, d1, d2; |
| #define memcpy(dst, src, cnt) __builtin_memcpy((dst), (src), (cnt)) |
| |
| asm volatile( |
| /* copy all full dwords */ |
| "rep movsl\n\t" |
| /* load count again */ |
| "movl %4, %%ecx\n\t" |
| /* ecx = ecx mod 4 */ |
| "andl $3, %%ecx\n\t" |
| /* are there last <=3 bytes? */ |
| "jz 1f\n\t" |
| /* copy last <=3 bytes */ |
| "rep movsb\n\t" |
| /* exit from asm block */ |
| "1:\n" |
| : "=&c" (d0), "=&D" (d1), "=&S" (d2) |
| : "0" ((unative_t) (cnt / 4)), "g" ((unative_t) cnt), "1" ((unative_t) dst), "2" ((unative_t) src) |
| : "memory"); |
| extern void memsetw(uintptr_t dst, size_t cnt, uint16_t x); |
| extern void memsetb(uintptr_t dst, size_t cnt, uint8_t x); |
| |
| return dst; |
| } |
| extern int memcmp(uintptr_t src, uintptr_t dst, int cnt); |
| |
| |
| /** Compare memory regions for equality |
| * |
| * Compare a given number of bytes (3rd argument) |
| * at memory locations defined by 1st and 2nd argument |
| * for equality. If bytes are equal function returns 0. |
| * |
| * @param src Region 1 |
| * @param dst Region 2 |
| * @param cnt Number of bytes |
| * @return Zero if bytes are equal, non-zero otherwise |
| */ |
| static inline int memcmp(const void * src, const void * dst, size_t cnt) |
| { |
| uint32_t d0, d1, d2; |
| int ret; |
| |
| asm ( |
| "repe cmpsb\n\t" |
| "je 1f\n\t" |
| "movl %3, %0\n\t" |
| "addl $1, %0\n\t" |
| "1:\n" |
| : "=a" (ret), "=&S" (d0), "=&D" (d1), "=&c" (d2) |
| : "0" (0), "1" ((unative_t) src), "2" ((unative_t) dst), "3" ((unative_t) cnt) |
| ); |
| |
| return ret; |
| } |
| |
| /** Fill memory with words |
| * Fill a given number of words (2nd argument) |
| * at memory defined by 1st argument with the |
| * word value defined by 3rd argument. |
| * |
| * @param dst Destination |
| * @param cnt Number of words |
| * @param x Value to fill |
| */ |
| static inline void memsetw(uintptr_t dst, size_t cnt, uint16_t x) |
| { |
| uint32_t d0, d1; |
| |
| asm volatile ( |
| "rep stosw\n\t" |
| : "=&D" (d0), "=&c" (d1), "=&a" (x) |
| : "0" (dst), "1" (cnt), "2" (x) |
| : "memory" |
| ); |
| |
| } |
| |
| /** Fill memory with bytes |
| * Fill a given number of bytes (2nd argument) |
| * at memory defined by 1st argument with the |
| * word value defined by 3rd argument. |
| * |
| * @param dst Destination |
| * @param cnt Number of bytes |
| * @param x Value to fill |
| */ |
| static inline void memsetb(uintptr_t dst, size_t cnt, uint8_t x) |
| { |
| uint32_t d0, d1; |
| |
| asm volatile ( |
| "rep stosb\n\t" |
| : "=&D" (d0), "=&c" (d1), "=&a" (x) |
| : "0" (dst), "1" (cnt), "2" (x) |
| : "memory" |
| ); |
| |
| } |
| |
| #endif |
| |
| /** @} |