//quick inline asm statements performing the swap_byte for key_scheduling
inline void swap_byte(unsigned char *x, unsigned char *y)
{
unsigned char t;
asm("movl %1, %%eax;"
"movl %%eax, %0;"
:"=r"(t)
:"r"(*x)
:"%eax");
asm("movl %1, %%eax;"
"movl %%eax, %0;"
:"=r"(*x)
:"r"(*y)
:"%eax");
asm("movl %1, %%eax;"
"movl %%eax, %0;"
:"=r"(*y)
:"r"(t)
:"%eax");
}
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在这里,我想从交换焦炭x和存储y,与同为y至x.我已经通过更改movl来编译这些指令mov但没有成功.编译/链接的问题在哪里?
这是cygwin中编译的输出:
$ gcc rc4_main.c -o rc4ex
/tmp/ccy0wo6H.s: Assembler messages:
/tmp/ccy0wo6H.s:18: Error: operand type mismatch for `mov'
/tmp/ccy0wo6H.s:18: Error: …Run Code Online (Sandbox Code Playgroud)