24 lines
273 B
C
24 lines
273 B
C
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#include "u.h"
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#include "libc.h"
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int
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tas(long *x)
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{
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int v;
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__asm__( "movl $1, %%eax\n\t"
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"xchgl %%eax,(%%rcx)"
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: "=a" (v)
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: "c" (x)
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);
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switch(v) {
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case 0:
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case 1:
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return v;
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default:
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print("canlock: corrupted 0x%lux\n", v);
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return 1;
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}
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}
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