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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4973 | right-hear | 1 | /* Copyright (C) 1999 DJ Delorie, see COPYING.DJ for details */ |
| 2 | /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */ |
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| 3 | /* Modified by SET to copy in reverse order */ |
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| 4 | # This routine moves %ecx bytes from %ds:%esi to %es:%edi. It clobbers |
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| 5 | # %eax, %ecx, %esi, %edi, and eflags. |
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| 6 | #include |
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| 7 | #include |
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| 8 | |||
| 9 | .file "djmdr.s" |
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| 10 | .text |
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| 11 | .balign 16,,7 |
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| 12 | MK_C_SYM(__dj_movedata_rev) |
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| 13 | std |
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| 14 | # Add the counter to the index |
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| 15 | addl %ecx,%edi |
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| 16 | addl %ecx,%esi |
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| 17 | decl %esi |
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| 18 | decl %edi |
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| 19 | |||
| 20 | cmpl $15,%ecx |
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| 21 | jle small_move |
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| 22 | jmp mod_4_check |
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| 23 | |||
| 24 | # Transfer bytes until either %esi or %edi is aligned % 3 |
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| 25 | align_mod_4: |
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| 26 | movsb |
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| 27 | decl %ecx |
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| 28 | mod_4_check: |
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| 29 | movl %esi,%eax |
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| 30 | andl $3,%eax |
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| 31 | cmpl $3,%eax |
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| 32 | jz big_move |
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| 33 | movl %edi,%eax |
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| 34 | andl $3,%eax |
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| 35 | cmpl $3,%eax |
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| 36 | jnz align_mod_4 |
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| 37 | |||
| 38 | big_move: |
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| 39 | movb %cl,%al # We will store leftover count in %al |
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| 40 | shrl $2,%ecx |
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| 41 | andb $3,%al |
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| 42 | # Now retrocess the index 3 positions |
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| 43 | subl $3,%edi |
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| 44 | subl $3,%esi |
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| 45 | rep |
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| 46 | movsl |
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| 47 | |||
| 48 | # %ecx known to be zero here, so insert the leftover count in %al |
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| 49 | movb %al,%cl |
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| 50 | |||
| 51 | # advance the index by 3 |
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| 52 | addl $3,%edi |
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| 53 | addl $3,%esi |
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| 54 | |||
| 55 | small_move: |
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| 56 | rep |
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| 57 | movsb |
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| 58 | ret |