xref: /OK3568_Linux_fs/kernel/arch/x86/math-emu/round_Xsig.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun/*---------------------------------------------------------------------------+
3*4882a593Smuzhiyun |  round_Xsig.S                                                             |
4*4882a593Smuzhiyun |                                                                           |
5*4882a593Smuzhiyun | Copyright (C) 1992,1993,1994,1995                                         |
6*4882a593Smuzhiyun |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      |
7*4882a593Smuzhiyun |                       Australia.  E-mail billm@jacobi.maths.monash.edu.au |
8*4882a593Smuzhiyun |                                                                           |
9*4882a593Smuzhiyun | Normalize and round a 12 byte quantity.                                   |
10*4882a593Smuzhiyun | Call from C as:                                                           |
11*4882a593Smuzhiyun |   int round_Xsig(Xsig *n)                                                 |
12*4882a593Smuzhiyun |                                                                           |
13*4882a593Smuzhiyun | Normalize a 12 byte quantity.                                             |
14*4882a593Smuzhiyun | Call from C as:                                                           |
15*4882a593Smuzhiyun |   int norm_Xsig(Xsig *n)                                                  |
16*4882a593Smuzhiyun |                                                                           |
17*4882a593Smuzhiyun | Each function returns the size of the shift (nr of bits).                 |
18*4882a593Smuzhiyun |                                                                           |
19*4882a593Smuzhiyun +---------------------------------------------------------------------------*/
20*4882a593Smuzhiyun	.file	"round_Xsig.S"
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun#include "fpu_emu.h"
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun.text
26*4882a593SmuzhiyunSYM_FUNC_START(round_Xsig)
27*4882a593Smuzhiyun	pushl	%ebp
28*4882a593Smuzhiyun	movl	%esp,%ebp
29*4882a593Smuzhiyun	pushl	%ebx		/* Reserve some space */
30*4882a593Smuzhiyun	pushl	%ebx
31*4882a593Smuzhiyun	pushl	%esi
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun	movl	PARAM1,%esi
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun	movl	8(%esi),%edx
36*4882a593Smuzhiyun	movl	4(%esi),%ebx
37*4882a593Smuzhiyun	movl	(%esi),%eax
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun	movl	$0,-4(%ebp)
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun	orl	%edx,%edx	/* ms bits */
42*4882a593Smuzhiyun	js	L_round		/* Already normalized */
43*4882a593Smuzhiyun	jnz	L_shift_1	/* Shift left 1 - 31 bits */
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun	movl	%ebx,%edx
46*4882a593Smuzhiyun	movl	%eax,%ebx
47*4882a593Smuzhiyun	xorl	%eax,%eax
48*4882a593Smuzhiyun	movl	$-32,-4(%ebp)
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun/* We need to shift left by 1 - 31 bits */
51*4882a593SmuzhiyunL_shift_1:
52*4882a593Smuzhiyun	bsrl	%edx,%ecx	/* get the required shift in %ecx */
53*4882a593Smuzhiyun	subl	$31,%ecx
54*4882a593Smuzhiyun	negl	%ecx
55*4882a593Smuzhiyun	subl	%ecx,-4(%ebp)
56*4882a593Smuzhiyun	shld	%cl,%ebx,%edx
57*4882a593Smuzhiyun	shld	%cl,%eax,%ebx
58*4882a593Smuzhiyun	shl	%cl,%eax
59*4882a593Smuzhiyun
60*4882a593SmuzhiyunL_round:
61*4882a593Smuzhiyun	testl	$0x80000000,%eax
62*4882a593Smuzhiyun	jz	L_exit
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun	addl	$1,%ebx
65*4882a593Smuzhiyun	adcl	$0,%edx
66*4882a593Smuzhiyun	jnz	L_exit
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun	movl	$0x80000000,%edx
69*4882a593Smuzhiyun	incl	-4(%ebp)
70*4882a593Smuzhiyun
71*4882a593SmuzhiyunL_exit:
72*4882a593Smuzhiyun	movl	%edx,8(%esi)
73*4882a593Smuzhiyun	movl	%ebx,4(%esi)
74*4882a593Smuzhiyun	movl	%eax,(%esi)
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun	movl	-4(%ebp),%eax
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun	popl	%esi
79*4882a593Smuzhiyun	popl	%ebx
80*4882a593Smuzhiyun	leave
81*4882a593Smuzhiyun	RET
82*4882a593SmuzhiyunSYM_FUNC_END(round_Xsig)
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun
86*4882a593SmuzhiyunSYM_FUNC_START(norm_Xsig)
87*4882a593Smuzhiyun	pushl	%ebp
88*4882a593Smuzhiyun	movl	%esp,%ebp
89*4882a593Smuzhiyun	pushl	%ebx		/* Reserve some space */
90*4882a593Smuzhiyun	pushl	%ebx
91*4882a593Smuzhiyun	pushl	%esi
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun	movl	PARAM1,%esi
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun	movl	8(%esi),%edx
96*4882a593Smuzhiyun	movl	4(%esi),%ebx
97*4882a593Smuzhiyun	movl	(%esi),%eax
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun	movl	$0,-4(%ebp)
100*4882a593Smuzhiyun
101*4882a593Smuzhiyun	orl	%edx,%edx	/* ms bits */
102*4882a593Smuzhiyun	js	L_n_exit		/* Already normalized */
103*4882a593Smuzhiyun	jnz	L_n_shift_1	/* Shift left 1 - 31 bits */
104*4882a593Smuzhiyun
105*4882a593Smuzhiyun	movl	%ebx,%edx
106*4882a593Smuzhiyun	movl	%eax,%ebx
107*4882a593Smuzhiyun	xorl	%eax,%eax
108*4882a593Smuzhiyun	movl	$-32,-4(%ebp)
109*4882a593Smuzhiyun
110*4882a593Smuzhiyun	orl	%edx,%edx	/* ms bits */
111*4882a593Smuzhiyun	js	L_n_exit	/* Normalized now */
112*4882a593Smuzhiyun	jnz	L_n_shift_1	/* Shift left 1 - 31 bits */
113*4882a593Smuzhiyun
114*4882a593Smuzhiyun	movl	%ebx,%edx
115*4882a593Smuzhiyun	movl	%eax,%ebx
116*4882a593Smuzhiyun	xorl	%eax,%eax
117*4882a593Smuzhiyun	addl	$-32,-4(%ebp)
118*4882a593Smuzhiyun	jmp	L_n_exit	/* Might not be normalized,
119*4882a593Smuzhiyun	                           but shift no more. */
120*4882a593Smuzhiyun
121*4882a593Smuzhiyun/* We need to shift left by 1 - 31 bits */
122*4882a593SmuzhiyunL_n_shift_1:
123*4882a593Smuzhiyun	bsrl	%edx,%ecx	/* get the required shift in %ecx */
124*4882a593Smuzhiyun	subl	$31,%ecx
125*4882a593Smuzhiyun	negl	%ecx
126*4882a593Smuzhiyun	subl	%ecx,-4(%ebp)
127*4882a593Smuzhiyun	shld	%cl,%ebx,%edx
128*4882a593Smuzhiyun	shld	%cl,%eax,%ebx
129*4882a593Smuzhiyun	shl	%cl,%eax
130*4882a593Smuzhiyun
131*4882a593SmuzhiyunL_n_exit:
132*4882a593Smuzhiyun	movl	%edx,8(%esi)
133*4882a593Smuzhiyun	movl	%ebx,4(%esi)
134*4882a593Smuzhiyun	movl	%eax,(%esi)
135*4882a593Smuzhiyun
136*4882a593Smuzhiyun	movl	-4(%ebp),%eax
137*4882a593Smuzhiyun
138*4882a593Smuzhiyun	popl	%esi
139*4882a593Smuzhiyun	popl	%ebx
140*4882a593Smuzhiyun	leave
141*4882a593Smuzhiyun	RET
142*4882a593SmuzhiyunSYM_FUNC_END(norm_Xsig)
143