Return to memcpy.s CVS log

Up to [MW Coherent from dump] / coherent / b / kernel / i386

Annotation of coherent/b/kernel/i386/memcpy.s, revision 1.1.1.1

1.1       root        1:        .intelorder
                      2: //////////
                      3: / libc/string/i386/memcpy.s
                      4: / i386 C string library.
                      5: / ANSI 4.11.2.1.
                      6: //////////
                      7: 
                      8: //////////
                      9: / void *
                     10: / memcpy(void *To, void *From, size_t Count)
                     11: /
                     12: / Copy Count bytes from From to To, return To.
                     13: / Copies first by dwords, then by words, then by bytes, for efficiency;
                     14: / does not try to align the arguments.
                     15: //////////
                     16: 
                     17: To     .equ    12
                     18: From   .equ    To+4
                     19: Count  .equ    From+4
                     20: 
                     21:        .globl  memcpy
                     22:        .globl  _memcpy
                     23: 
                     24: memcpy:
                     25:        push    %esi
                     26:        push    %edi
                     27: 
                     28:        movl    %esi, From(%esp)        / From to ESI
                     29:        movl    %edi, To(%esp)          / To to EDI
                     30:        movl    %ecx, Count(%esp)       / Count to ECX
                     31:        movl    %eax, %edi              / Return value to EAX
                     32: 
                     33: _memcpy:                               / memmove() entry point
                     34:        push    %es                     / save es
                     35:        push    %ds                     / copy ds to es
                     36:        pop     %es
                     37:        cld
                     38:        movl    %edx, %ecx              / Save Count in EDX
                     39:        shrl    %ecx, $2                / Count/4
                     40:        rep
                     41:        movsl                           / move Count/4 dwords
                     42:        jnc     ?byte                   / CF contains Count bit 1 from shrl above
                     43:        movsw                           / move a word
                     44: 
                     45: ?byte:
                     46:        shrl    %edx, $1
                     47:        jnc     ?done
                     48:        movsb                           / move a byte
                     49: 
                     50: ?done:
                     51:        pop     %es
                     52:        pop     %edi
                     53:        pop     %esi
                     54:        ret
                     55: 
                     56: / end of libc/string/i386/memcpy.s

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.