usr/src/libnm/asin.s

#double asin(arg)
#double arg; -1.0<=arg<=1.0 or an out of range error return
#method: call atan() after range reduction
# calls: satan (internal entry point of atan.s), _sqrt
# J F Jarvis August 8, 1078
.globl  _asin
.globl  _errno
.globl  _sqrt
.globl  satan
.set    EDOM,33
.text
.align  1
_asin:
        .word   0x0c0
        movd    4(ap),r6
        jgtr    a1
        mnegd   r6,r6
a1:     cmpd    r6,$0d1.0e+0
        jleq    a2
        movl    $EDOM,_errno
        clrd    r0
        ret
#
a2:     muld3   r6,r6,r0
        subd3   r0,$0d1.0e+0,-(sp)
        calls   $2,_sqrt
        cmpd    r6,$0d0.6875
        jleq    a3
        divd2   r6,r0
        jsb     satan
        subd3   r0,pio2,r0
        jbr     a4
a3:     divd3   r0,r6,r0
        jsb     satan
a4:     tstd    4(ap)
        jleq    a5
        ret
a5:     mnegd   r0,r0
        ret
.data
.align  3
pio2: .double 0d1.57079632679489661923e+0