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extern "C" int cmake_plus_one_cxx(int *arg);
extern "C" int cmake_plus_one_cxx_asm(int *arg);
int cmake_plus_one_cxx(int *arg) {
return *arg + 1;
}
int cmake_plus_one_cxx_asm(int *arg) {
int value = 0;
asm volatile ( " movl (%1), %0\n"
" inc %0\n"
" jmp 1f\n"
" retq\n" // never executed, but a shortcut to determine how
// the assembler deals with `ret` instructions
"1:\n"
: "=r"(value)
: "r"(arg) );
return value;
}
asm(".text\n"
" .global cmake_plus_one_cxx_global_asm\n"
" .type cmake_plus_one_cxx_global_asm, @function\n"
"cmake_plus_one_cxx_global_asm:\n"
" movl (%rdi), %eax\n"
" inc %eax\n"
" retq\n" );
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