/* fls.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) | |
brz,pn %o0, 6f | |
mov 0, %o1 | |
sethi %hi(0xffff0000), %g3 | |
mov %o0, %g2 | |
andcc %o0, %g3, %g0 | |
be,pt %icc, 8f | |
mov 32, %o1 | |
sethi %hi(0xff000000), %g3 | |
andcc %g2, %g3, %g0 | |
bne,pt %icc, 3f | |
sethi %hi(0xf0000000), %g3 | |
sll %o0, 8, %o0 | |
1: | |
add %o1, -8, %o1 | |
sra %o0, 0, %o0 | |
mov %o0, %g2 | |
2: | |
sethi %hi(0xf0000000), %g3 | |
3: | |
andcc %g2, %g3, %g0 | |
bne,pt %icc, 4f | |
sethi %hi(0xc0000000), %g3 | |
sll %o0, 4, %o0 | |
add %o1, -4, %o1 | |
sra %o0, 0, %o0 | |
mov %o0, %g2 | |
4: | |
andcc %g2, %g3, %g0 | |
be,a,pt %icc, 7f | |
sll %o0, 2, %o0 | |
5: | |
xnor %g0, %o0, %o0 | |
srl %o0, 31, %o0 | |
sub %o1, %o0, %o1 | |
6: | |
jmp %o7 + 8 | |
sra %o1, 0, %o0 | |
7: | |
add %o1, -2, %o1 | |
ba,pt %xcc, 5b | |
sra %o0, 0, %o0 | |
8: | |
sll %o0, 16, %o0 | |
sethi %hi(0xff000000), %g3 | |
sra %o0, 0, %o0 | |
mov %o0, %g2 | |
andcc %g2, %g3, %g0 | |
bne,pt %icc, 2b | |
mov 16, %o1 | |
ba,pt %xcc, 1b | |
sll %o0, 8, %o0 | |
ENDPROC(fls) | |
EXPORT_SYMBOL(fls) |