22 lines
587 B
C++
22 lines
587 B
C++
extern "C" int cc_plus_one_cxx(int *arg);
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extern "C" int cc_plus_one_cxx_asm(int *arg);
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int cc_plus_one_cxx(int *arg) {
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return *arg + 1;
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}
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int cc_plus_one_cxx_asm(int *arg) {
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int value = 0;
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asm volatile ( " movl (%1), %0\n"
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" inc %0\n"
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" jmp 1f\n"
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" retq\n" // never executed, but a shortcut to determine how
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// the assembler deals with `ret` instructions
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"1:\n"
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: "=r"(value)
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: "r"(arg) );
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return value;
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}
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