xref: /OK3568_Linux_fs/kernel/arch/m68k/fpsp040/ssinh.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun|
2*4882a593Smuzhiyun|	ssinh.sa 3.1 12/10/90
3*4882a593Smuzhiyun|
4*4882a593Smuzhiyun|       The entry point sSinh computes the hyperbolic sine of
5*4882a593Smuzhiyun|       an input argument; sSinhd does the same except for denormalized
6*4882a593Smuzhiyun|       input.
7*4882a593Smuzhiyun|
8*4882a593Smuzhiyun|       Input: Double-extended number X in location pointed to
9*4882a593Smuzhiyun|		by address register a0.
10*4882a593Smuzhiyun|
11*4882a593Smuzhiyun|       Output: The value sinh(X) returned in floating-point register Fp0.
12*4882a593Smuzhiyun|
13*4882a593Smuzhiyun|       Accuracy and Monotonicity: The returned result is within 3 ulps in
14*4882a593Smuzhiyun|               64 significant bit, i.e. within 0.5001 ulp to 53 bits if the
15*4882a593Smuzhiyun|               result is subsequently rounded to double precision. The
16*4882a593Smuzhiyun|               result is provably monotonic in double precision.
17*4882a593Smuzhiyun|
18*4882a593Smuzhiyun|       Speed: The program sSINH takes approximately 280 cycles.
19*4882a593Smuzhiyun|
20*4882a593Smuzhiyun|       Algorithm:
21*4882a593Smuzhiyun|
22*4882a593Smuzhiyun|       SINH
23*4882a593Smuzhiyun|       1. If |X| > 16380 log2, go to 3.
24*4882a593Smuzhiyun|
25*4882a593Smuzhiyun|       2. (|X| <= 16380 log2) Sinh(X) is obtained by the formulae
26*4882a593Smuzhiyun|               y = |X|, sgn = sign(X), and z = expm1(Y),
27*4882a593Smuzhiyun|               sinh(X) = sgn*(1/2)*( z + z/(1+z) ).
28*4882a593Smuzhiyun|          Exit.
29*4882a593Smuzhiyun|
30*4882a593Smuzhiyun|       3. If |X| > 16480 log2, go to 5.
31*4882a593Smuzhiyun|
32*4882a593Smuzhiyun|       4. (16380 log2 < |X| <= 16480 log2)
33*4882a593Smuzhiyun|               sinh(X) = sign(X) * exp(|X|)/2.
34*4882a593Smuzhiyun|          However, invoking exp(|X|) may cause premature overflow.
35*4882a593Smuzhiyun|          Thus, we calculate sinh(X) as follows:
36*4882a593Smuzhiyun|             Y       := |X|
37*4882a593Smuzhiyun|             sgn     := sign(X)
38*4882a593Smuzhiyun|             sgnFact := sgn * 2**(16380)
39*4882a593Smuzhiyun|             Y'      := Y - 16381 log2
40*4882a593Smuzhiyun|             sinh(X) := sgnFact * exp(Y').
41*4882a593Smuzhiyun|          Exit.
42*4882a593Smuzhiyun|
43*4882a593Smuzhiyun|       5. (|X| > 16480 log2) sinh(X) must overflow. Return
44*4882a593Smuzhiyun|          sign(X)*Huge*Huge to generate overflow and an infinity with
45*4882a593Smuzhiyun|          the appropriate sign. Huge is the largest finite number in
46*4882a593Smuzhiyun|          extended format. Exit.
47*4882a593Smuzhiyun|
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun|		Copyright (C) Motorola, Inc. 1990
50*4882a593Smuzhiyun|			All Rights Reserved
51*4882a593Smuzhiyun|
52*4882a593Smuzhiyun|       For details on the license for this file, please see the
53*4882a593Smuzhiyun|       file, README, in this same directory.
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun|SSINH	idnt	2,1 | Motorola 040 Floating Point Software Package
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun	|section	8
58*4882a593Smuzhiyun
59*4882a593SmuzhiyunT1:	.long 0x40C62D38,0xD3D64634 | ... 16381 LOG2 LEAD
60*4882a593SmuzhiyunT2:	.long 0x3D6F90AE,0xB1E75CC7 | ... 16381 LOG2 TRAIL
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun	|xref	t_frcinx
63*4882a593Smuzhiyun	|xref	t_ovfl
64*4882a593Smuzhiyun	|xref	t_extdnrm
65*4882a593Smuzhiyun	|xref	setox
66*4882a593Smuzhiyun	|xref	setoxm1
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun	.global	ssinhd
69*4882a593Smuzhiyunssinhd:
70*4882a593Smuzhiyun|--SINH(X) = X FOR DENORMALIZED X
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun	bra	t_extdnrm
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun	.global	ssinh
75*4882a593Smuzhiyunssinh:
76*4882a593Smuzhiyun	fmovex	(%a0),%fp0	| ...LOAD INPUT
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun	movel	(%a0),%d0
79*4882a593Smuzhiyun	movew	4(%a0),%d0
80*4882a593Smuzhiyun	movel	%d0,%a1		| save a copy of original (compacted) operand
81*4882a593Smuzhiyun	andl	#0x7FFFFFFF,%d0
82*4882a593Smuzhiyun	cmpl	#0x400CB167,%d0
83*4882a593Smuzhiyun	bgts	SINHBIG
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun|--THIS IS THE USUAL CASE, |X| < 16380 LOG2
86*4882a593Smuzhiyun|--Y = |X|, Z = EXPM1(Y), SINH(X) = SIGN(X)*(1/2)*( Z + Z/(1+Z) )
87*4882a593Smuzhiyun
88*4882a593Smuzhiyun	fabsx	%fp0		| ...Y = |X|
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun	moveml	%a1/%d1,-(%sp)
91*4882a593Smuzhiyun	fmovemx %fp0-%fp0,(%a0)
92*4882a593Smuzhiyun	clrl	%d1
93*4882a593Smuzhiyun	bsr	setoxm1		| ...FP0 IS Z = EXPM1(Y)
94*4882a593Smuzhiyun	fmovel	#0,%fpcr
95*4882a593Smuzhiyun	moveml	(%sp)+,%a1/%d1
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun	fmovex	%fp0,%fp1
98*4882a593Smuzhiyun	fadds	#0x3F800000,%fp1	| ...1+Z
99*4882a593Smuzhiyun	fmovex	%fp0,-(%sp)
100*4882a593Smuzhiyun	fdivx	%fp1,%fp0		| ...Z/(1+Z)
101*4882a593Smuzhiyun	movel	%a1,%d0
102*4882a593Smuzhiyun	andl	#0x80000000,%d0
103*4882a593Smuzhiyun	orl	#0x3F000000,%d0
104*4882a593Smuzhiyun	faddx	(%sp)+,%fp0
105*4882a593Smuzhiyun	movel	%d0,-(%sp)
106*4882a593Smuzhiyun
107*4882a593Smuzhiyun	fmovel	%d1,%fpcr
108*4882a593Smuzhiyun	fmuls	(%sp)+,%fp0	|last fp inst - possible exceptions set
109*4882a593Smuzhiyun
110*4882a593Smuzhiyun	bra	t_frcinx
111*4882a593Smuzhiyun
112*4882a593SmuzhiyunSINHBIG:
113*4882a593Smuzhiyun	cmpl	#0x400CB2B3,%d0
114*4882a593Smuzhiyun	bgt	t_ovfl
115*4882a593Smuzhiyun	fabsx	%fp0
116*4882a593Smuzhiyun	fsubd	T1(%pc),%fp0	| ...(|X|-16381LOG2_LEAD)
117*4882a593Smuzhiyun	movel	#0,-(%sp)
118*4882a593Smuzhiyun	movel	#0x80000000,-(%sp)
119*4882a593Smuzhiyun	movel	%a1,%d0
120*4882a593Smuzhiyun	andl	#0x80000000,%d0
121*4882a593Smuzhiyun	orl	#0x7FFB0000,%d0
122*4882a593Smuzhiyun	movel	%d0,-(%sp)	| ...EXTENDED FMT
123*4882a593Smuzhiyun	fsubd	T2(%pc),%fp0	| ...|X| - 16381 LOG2, ACCURATE
124*4882a593Smuzhiyun
125*4882a593Smuzhiyun	movel	%d1,-(%sp)
126*4882a593Smuzhiyun	clrl	%d1
127*4882a593Smuzhiyun	fmovemx %fp0-%fp0,(%a0)
128*4882a593Smuzhiyun	bsr	setox
129*4882a593Smuzhiyun	fmovel	(%sp)+,%fpcr
130*4882a593Smuzhiyun
131*4882a593Smuzhiyun	fmulx	(%sp)+,%fp0	|possible exception
132*4882a593Smuzhiyun	bra	t_frcinx
133*4882a593Smuzhiyun
134*4882a593Smuzhiyun	|end
135