diff options
Diffstat (limited to 'arch/x86/lib/bitops_64.c')
| -rw-r--r-- | arch/x86/lib/bitops_64.c | 175 |
1 files changed, 0 insertions, 175 deletions
diff --git a/arch/x86/lib/bitops_64.c b/arch/x86/lib/bitops_64.c deleted file mode 100644 index 0e8f491e6cc..00000000000 --- a/arch/x86/lib/bitops_64.c +++ /dev/null @@ -1,175 +0,0 @@ -#include <linux/bitops.h> - -#undef find_first_zero_bit -#undef find_next_zero_bit -#undef find_first_bit -#undef find_next_bit - -static inline long -__find_first_zero_bit(const unsigned long * addr, unsigned long size) -{ - long d0, d1, d2; - long res; - - /* - * We must test the size in words, not in bits, because - * otherwise incoming sizes in the range -63..-1 will not run - * any scasq instructions, and then the flags used by the je - * instruction will have whatever random value was in place - * before. Nobody should call us like that, but - * find_next_zero_bit() does when offset and size are at the - * same word and it fails to find a zero itself. - */ - size += 63; - size >>= 6; - if (!size) - return 0; - asm volatile( - " repe; scasq\n" - " je 1f\n" - " xorq -8(%%rdi),%%rax\n" - " subq $8,%%rdi\n" - " bsfq %%rax,%%rdx\n" - "1: subq %[addr],%%rdi\n" - " shlq $3,%%rdi\n" - " addq %%rdi,%%rdx" - :"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2) - :"0" (0ULL), "1" (size), "2" (addr), "3" (-1ULL), - [addr] "S" (addr) : "memory"); - /* - * Any register would do for [addr] above, but GCC tends to - * prefer rbx over rsi, even though rsi is readily available - * and doesn't have to be saved. - */ - return res; -} - -/** - * find_first_zero_bit - find the first zero bit in a memory region - * @addr: The address to start the search at - * @size: The maximum size to search - * - * Returns the bit-number of the first zero bit, not the number of the byte - * containing a bit. - */ -long find_first_zero_bit(const unsigned long * addr, unsigned long size) -{ - return __find_first_zero_bit (addr, size); -} - -/** - * find_next_zero_bit - find the next zero bit in a memory region - * @addr: The address to base the search on - * @offset: The bitnumber to start searching at - * @size: The maximum size to search - */ -long find_next_zero_bit (const unsigned long * addr, long size, long offset) -{ - const unsigned long * p = addr + (offset >> 6); - unsigned long set = 0; - unsigned long res, bit = offset&63; - - if (bit) { - /* - * Look for zero in first word - */ - asm("bsfq %1,%0\n\t" - "cmoveq %2,%0" - : "=r" (set) - : "r" (~(*p >> bit)), "r"(64L)); - if (set < (64 - bit)) - return set + offset; - set = 64 - bit; - p++; - } - /* - * No zero yet, search remaining full words for a zero - */ - res = __find_first_zero_bit (p, size - 64 * (p - addr)); - - return (offset + set + res); -} - -static inline long -__find_first_bit(const unsigned long * addr, unsigned long size) -{ - long d0, d1; - long res; - - /* - * We must test the size in words, not in bits, because - * otherwise incoming sizes in the range -63..-1 will not run - * any scasq instructions, and then the flags used by the jz - * instruction will have whatever random value was in place - * before. Nobody should call us like that, but - * find_next_bit() does when offset and size are at the same - * word and it fails to find a one itself. - */ - size += 63; - size >>= 6; - if (!size) - return 0; - asm volatile( - " repe; scasq\n" - " jz 1f\n" - " subq $8,%%rdi\n" - " bsfq (%%rdi),%%rax\n" - "1: subq %[addr],%%rdi\n" - " shlq $3,%%rdi\n" - " addq %%rdi,%%rax" - :"=a" (res), "=&c" (d0), "=&D" (d1) - :"0" (0ULL), "1" (size), "2" (addr), - [addr] "r" (addr) : "memory"); - return res; -} - -/** - * find_first_bit - find the first set bit in a memory region - * @addr: The address to start the search at - * @size: The maximum size to search - * - * Returns the bit-number of the first set bit, not the number of the byte - * containing a bit. - */ -long find_first_bit(const unsigned long * addr, unsigned long size) -{ - return __find_first_bit(addr,size); -} - -/** - * find_next_bit - find the first set bit in a memory region - * @addr: The address to base the search on - * @offset: The bitnumber to start searching at - * @size: The maximum size to search - */ -long find_next_bit(const unsigned long * addr, long size, long offset) -{ - const unsigned long * p = addr + (offset >> 6); - unsigned long set = 0, bit = offset & 63, res; - - if (bit) { - /* - * Look for nonzero in the first 64 bits: - */ - asm("bsfq %1,%0\n\t" - "cmoveq %2,%0\n\t" - : "=r" (set) - : "r" (*p >> bit), "r" (64L)); - if (set < (64 - bit)) - return set + offset; - set = 64 - bit; - p++; - } - /* - * No set bit yet, search remaining full words for a bit - */ - res = __find_first_bit (p, size - 64 * (p - addr)); - return (offset + set + res); -} - -#include <linux/module.h> - -EXPORT_SYMBOL(find_next_bit); -EXPORT_SYMBOL(find_first_bit); -EXPORT_SYMBOL(find_first_zero_bit); -EXPORT_SYMBOL(find_next_zero_bit); |