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SubjectRe: Valgrinding the kernel?
On Fri, Jul 06, 2007 at 12:51:27PM -0700, Jeremy Fitzhardinge wrote:
> The virtual CPU code has been competely rewritten since then. If its a
> non-gcc generated instruction, its possible the new code
> parser/generator hasn't been taught to deal with it.

It's not from gcc - it's from the i386 bitops.h:

static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
{
int d0, d1, d2;
int res;
if (!size)
return 0;
/* This looks at memory. Mark it volatile to tell gcc not to move it around */
__asm__ __volatile__(
"movl $-1,%%eax\n\t"
"xorl %%edx,%%edx\n\t"
"repe; scasl\n\t"
"je 1f\n\t"
"xorl -4(%%edi),%%eax\n\t"
"subl $4,%%edi\n\t"
"bsfl %%eax,%%edx\n"
"1:\tsubl %%ebx,%%edi\n\t"
"shll $3,%%edi\n\t"
"addl %%edi,%%edx"
:"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
:"1" ((size + 31) >> 5), "2" (addr), "b" (addr) : "memory");
return res;
}
Jeff

--
Work email - jdike at linux dot intel dot com
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