62 lines
752 B
NASM
62 lines
752 B
NASM
//
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// prog1.asm -- an assembler example with global variables
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//
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//
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// compute the gcd of two positive numbers
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//
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// global Integer x;
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// global Integer y;
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// x = readInteger();
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// y = readInteger();
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// while (x != y) {
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// if (x > y) {
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// x = x - y;
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// } else {
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// y = y - x;
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// }
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// }
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// writeInteger(x);
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// writeCharacter('\n');
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// x = readInteger();
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rdint
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popg 0
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// y = readInteger();
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rdint
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popg 1
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// while ...
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L1:
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// x != y
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pushg 0 // 4
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pushg 1
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ne
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brf L2
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// if ...
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pushg 0
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pushg 1
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gt
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brf L3
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// x = x - y
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pushg 0
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pushg 1
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sub
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popg 0
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jmp L4
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L3:
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// y = y - x
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pushg 1 // 17
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pushg 0
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sub
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popg 1
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L4:
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jmp L1 // 21
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L2:
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// writeInteger(x);
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pushg 0 // 22
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wrint
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// writeCharacter('\n');
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pushc '\n'
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wrchr
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halt
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