316bbf6b92
the reference is from https://gcc.gnu.org/onlinedocs/gcc.pdf (5.0.0 pre-release）， section 6.43 （How to Use Inline Assembly Language in C Code） and http://www.ibiblio.org/gferg/ldp/GCC-Inline-Assembly-HOWTO.html syntax of basic asm statement: asm [ volatile ] ( Assembler Instructions ) syntax of extended asm statement asm [volatile] ( Assembler Template : Output Operands [ : Input Operands [ : Clobbers ] ]) Alanpsc, thanks you!
18 lines
441 B
C
18 lines
441 B
C
void inline ex1(void){
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asm ("movl $0xffff, %eax\n");
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}
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void inline ex2(void){
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unsigned cr0;
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asm volatile ("movl %%cr0, %0\n" :"=r"(cr0));
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cr0 |= 0x80000000;
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asm volatile ("movl %0, %%cr0\n" ::"r"(cr0));
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}
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void inline ex3(void){
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long __res, arg1 = 2, arg2 = 22, arg3 = 222, arg4 = 233;
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__asm__ __volatile__("int $0x80"
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: "=a" (__res)
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: "0" (11),"b" (arg1),"c" (arg2),"d" (arg3),"S" (arg4));
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}
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