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42 lines
651 B
Plaintext
42 lines
651 B
Plaintext
; The OS/K Team licenses this file to you under the MIT license.
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; See the LICENSE file in the project root for more information.
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;
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; void strrev(char *buf, const char *str)
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;
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strrev:
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test b[ax1], b[ax1]
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cmovz b[ax0], 0
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jz .4
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; save str's location
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; xxx why is dec'ing needed?
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lea rdx, b[ax1 + -1]
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; go to str's end, just before
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; the null terminator
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.1:
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test b[ax1+1], b[ax1+1]
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jz .2
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inc ax1
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jmp .1
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; copy, going backward though str
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; and forward through buf
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.2:
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mov b[ax0], b[ax1]
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cmp ax1, rdx
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je .3
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inc ax0
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dec ax1
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jmp .2
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.3:
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mov b[ax0+1], 0
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.4:
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ret
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