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Annotation of coherent/b/lib/libc/crt/i8086/blkmv.s, revision 1.1.1.1

1.1       root        1: ////////
                      2: /
                      3: / Intel 8086 C runtime.
                      4: / SMALL model.
                      5: /
                      6: ////////
                      7: 
                      8:        .globl  blkmv
                      9: 
                     10: ////////
                     11: /
                     12: / char *
                     13: / blkmv(dptr, sptr, nbytes);
                     14: / char *dptr;
                     15: / char *sptr;
                     16: /
                     17: / Copy a block of bytes of length "nbytes" from
                     18: / the block at "sptr" to the block at "dptr".
                     19: / This routine is called by generated code for structure assignment and
                     20: / for functions that return structures.
                     21: /
                     22: / The function returns the start address of the destination buffer.
                     23: / This is used as the return value of a function returning a structure.
                     24: /
                     25: ////////
                     26: 
                     27: blkmv: push    si                      / standard
                     28:        push    di                      / c
                     29:        push    bp                      / function
                     30:        mov     bp,sp                   / linkage.
                     31: 
                     32:        mov     cx,12(bp)               / grab the byte count.
                     33:        jcxz    L0                      / duck if no bytes.
                     34:        mov     si,10(bp)               / get source and
                     35:        mov     di, 8(bp)               / destination pointers.
                     36:        cld                             / move forward
                     37:        rep                             / copy
                     38:        movsb                           / the data block.
                     39: 
                     40: L0:    mov     ax, 8(bp)               / return dptr.
                     41: 
                     42:        mov     sp,bp                   / standard
                     43:        pop     bp                      / c
                     44:        pop     di                      / function
                     45:        pop     si                      / linkage.
                     46:        ret                             / done.

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