diff options
Diffstat (limited to 'arch/sparc/lib/fls64.S')
| -rw-r--r-- | arch/sparc/lib/fls64.S | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/sparc/lib/fls64.S b/arch/sparc/lib/fls64.S new file mode 100644 index 000000000000..c83e22ae9586 --- /dev/null +++ b/arch/sparc/lib/fls64.S @@ -0,0 +1,61 @@ +/* fls64.S: SPARC default __fls definition. + * + * SPARC default __fls definition, which follows the same algorithm as + * in generic __fls(). This function will be boot time patched on T4 + * and onward. + */ + +#include <linux/linkage.h> +#include <asm/export.h> + + .text + .register %g2, #scratch + .register %g3, #scratch +ENTRY(__fls) + mov -1, %g2 + sllx %g2, 32, %g2 + and %o0, %g2, %g2 + brnz,pt %g2, 1f + mov 63, %g1 + sllx %o0, 32, %o0 + mov 31, %g1 +1: + mov -1, %g2 + sllx %g2, 48, %g2 + and %o0, %g2, %g2 + brnz,pt %g2, 2f + mov -1, %g2 + sllx %o0, 16, %o0 + add %g1, -16, %g1 +2: + mov -1, %g2 + sllx %g2, 56, %g2 + and %o0, %g2, %g2 + brnz,pt %g2, 3f + mov -1, %g2 + sllx %o0, 8, %o0 + add %g1, -8, %g1 +3: + sllx %g2, 60, %g2 + and %o0, %g2, %g2 + brnz,pt %g2, 4f + mov -1, %g2 + sllx %o0, 4, %o0 + add %g1, -4, %g1 +4: + sllx %g2, 62, %g2 + and %o0, %g2, %g2 + brnz,pt %g2, 5f + mov -1, %g3 + sllx %o0, 2, %o0 + add %g1, -2, %g1 +5: + mov 0, %g2 + sllx %g3, 63, %g3 + and %o0, %g3, %o0 + movre %o0, 1, %g2 + sub %g1, %g2, %g1 + jmp %o7+8 + sra %g1, 0, %o0 +ENDPROC(__fls) +EXPORT_SYMBOL(__fls) |