36 lines
571 B
ArmAsm
36 lines
571 B
ArmAsm
|
/*
|
||
|
|
* Written by J.T. Conklin <jtc@netbsd.org>.
|
||
|
|
* Public domain.
|
||
|
|
*/
|
||
|
|
|
||
|
|
.file "ilogbf.S"
|
||
|
|
.text
|
||
|
|
.align 4
|
||
|
|
.globl _ilogbf
|
||
|
|
.def _ilogbf; .scl 2; .type 32; .endef
|
||
|
|
_ilogbf:
|
||
|
|
flds 4(%esp)
|
||
|
|
/* I added the following ugly construct because ilogb(+-Inf) is
|
||
|
|
required to return INT_MAX in ISO C99.
|
||
|
|
-- jakub@redhat.com. */
|
||
|
|
fxam /* Is NaN or +-Inf? */
|
||
|
|
fstsw %ax
|
||
|
|
movb $0x45, %dh
|
||
|
|
andb %ah, %dh
|
||
|
|
cmpb $0x05, %dh
|
||
|
|
je 1f /* Is +-Inf, jump. */
|
||
|
|
|
||
|
|
fxtract
|
||
|
|
pushl %eax
|
||
|
|
fstp %st
|
||
|
|
|
||
|
|
fistpl (%esp)
|
||
|
|
fwait
|
||
|
|
popl %eax
|
||
|
|
|
||
|
|
ret
|
||
|
|
|
||
|
|
1: fstp %st
|
||
|
|
movl $0x7fffffff, %eax
|
||
|
|
ret
|