What memory reference syntax is used to refer to the nth element of an array
in inline assembler? For example, the following x86 example doesn't
assemble:
void test()
{
unsigned _tmp[8];
__asm__ (
"movl %%edi, 12(%0)" // generates movl %edi, 12(-40(%ebp))
: "=m" (_tmp) : :
);
}
The following is kind of a workaround (ok for 1 reference):
void test2()
{
unsigned _tmp[8];
__asm__ (
"movl %%edi, %0" // generates movl %edi, -28(%ebp)
: "=m" (_tmp[3]) : :
);
}
But somewhat onerous and error-prone for several references:
void test3()
{
unsigned _tmp[8];
__asm__ (
"movl %%edi, %0 \n\t"
"movl %%esi, %1 \n\t"
"movl %%ebp, %2 \n\t"
"movl %%ebx, %3 \n\t"
"movl %%edx, %4 \n\t"
"movl %%ecx, %5 \n\t"
"movl %%eax, %6 \n\t"
: "=m" (_tmp[0]), "=m" (_tmp[1]), "=m" (_tmp[2]),
"=m" (_tmp[4]), "=m" (_tmp[5]), "=m" (_tmp[6]),
"=m" (_tmp[7]
: :
);
}
On a separate note, is there any plan to implement __attribute__(__naked__)
for x86? Restarting a processor exception is wicked tricky without being
able to alter the stack frame directly...
