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[/] [or1k/] [trunk/] [uclinux/] [uClinux-2.0.x/] [arch/] [i386/] [math-emu/] [shr_Xsig.S] - Blame information for rev 1767

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        .file   "shr_Xsig.S"
/*---------------------------------------------------------------------------+
 |  shr_Xsig.S                                                               |
 |                                                                           |
 | 12 byte right shift function                                              |
 |                                                                           |
 | Copyright (C) 1992,1994,1995                                              |
 |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      |
 |                       Australia.  E-mail billm@jacobi.maths.monash.edu.au |
 |                                                                           |
 | Call from C as:                                                           |
 |   void shr_Xsig(Xsig *arg, unsigned nr)                                   |
 |                                                                           |
 |   Extended shift right function.                                          |
 |   Fastest for small shifts.                                               |
 |   Shifts the 12 byte quantity pointed to by the first arg (arg)           |
 |   right by the number of bits specified by the second arg (nr).           |
 |                                                                           |
 +---------------------------------------------------------------------------*/
 
#include "fpu_emu.h"
 
.text
ENTRY(shr_Xsig)
        push    %ebp
        movl    %esp,%ebp
        pushl   %esi
        movl    PARAM2,%ecx
        movl    PARAM1,%esi
        cmpl    $32,%ecx        /* shrd only works for 0..31 bits */
        jnc     L_more_than_31
 
/* less than 32 bits */
        pushl   %ebx
        movl    (%esi),%eax     /* lsl */
        movl    4(%esi),%ebx    /* midl */
        movl    8(%esi),%edx    /* msl */
        shrd    %cl,%ebx,%eax
        shrd    %cl,%edx,%ebx
        shr     %cl,%edx
        movl    %eax,(%esi)
        movl    %ebx,4(%esi)
        movl    %edx,8(%esi)
        popl    %ebx
        popl    %esi
        leave
        ret
 
L_more_than_31:
        cmpl    $64,%ecx
        jnc     L_more_than_63
 
        subb    $32,%cl
        movl    4(%esi),%eax    /* midl */
        movl    8(%esi),%edx    /* msl */
        shrd    %cl,%edx,%eax
        shr     %cl,%edx
        movl    %eax,(%esi)
        movl    %edx,4(%esi)
        movl    $0,8(%esi)
        popl    %esi
        leave
        ret
 
L_more_than_63:
        cmpl    $96,%ecx
        jnc     L_more_than_95
 
        subb    $64,%cl
        movl    8(%esi),%eax    /* msl */
        shr     %cl,%eax
        xorl    %edx,%edx
        movl    %eax,(%esi)
        movl    %edx,4(%esi)
        movl    %edx,8(%esi)
        popl    %esi
        leave
        ret
 
L_more_than_95:
        xorl    %eax,%eax
        movl    %eax,(%esi)
        movl    %eax,4(%esi)
        movl    %eax,8(%esi)
        popl    %esi
        leave
        ret

Line No.	Rev	Author	Line
1	199	simons	`.file "shr_Xsig.S"`
2			`/*---------------------------------------------------------------------------+`
3			`\| shr_Xsig.S \|`
4			`\| \|`
5			`\| 12 byte right shift function \|`
6			`\| \|`
7			`\| Copyright (C) 1992,1994,1995 \|`
8			`\| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, \|`
9			`\| Australia. E-mail billm@jacobi.maths.monash.edu.au \|`
10			`\| \|`
11			`\| Call from C as: \|`
12			`\| void shr_Xsig(Xsig *arg, unsigned nr) \|`
13			`\| \|`
14			`\| Extended shift right function. \|`
15			`\| Fastest for small shifts. \|`
16			`\| Shifts the 12 byte quantity pointed to by the first arg (arg) \|`
17			`\| right by the number of bits specified by the second arg (nr). \|`
18			`\| \|`
19			`+---------------------------------------------------------------------------*/`
20
21			`#include "fpu_emu.h"`
22
23			`.text`
24			`ENTRY(shr_Xsig)`
25			`push %ebp`
26			`movl %esp,%ebp`
27			`pushl %esi`
28			`movl PARAM2,%ecx`
29			`movl PARAM1,%esi`
30			`cmpl $32,%ecx /* shrd only works for 0..31 bits */`
31			`jnc L_more_than_31`
32
33			`/* less than 32 bits */`
34			`pushl %ebx`
35			`movl (%esi),%eax /* lsl */`
36			`movl 4(%esi),%ebx /* midl */`
37			`movl 8(%esi),%edx /* msl */`
38			`shrd %cl,%ebx,%eax`
39			`shrd %cl,%edx,%ebx`
40			`shr %cl,%edx`
41			`movl %eax,(%esi)`
42			`movl %ebx,4(%esi)`
43			`movl %edx,8(%esi)`
44			`popl %ebx`
45			`popl %esi`
46			`leave`
47			`ret`
48
49			`L_more_than_31:`
50			`cmpl $64,%ecx`
51			`jnc L_more_than_63`
52
53			`subb $32,%cl`
54			`movl 4(%esi),%eax /* midl */`
55			`movl 8(%esi),%edx /* msl */`
56			`shrd %cl,%edx,%eax`
57			`shr %cl,%edx`
58			`movl %eax,(%esi)`
59			`movl %edx,4(%esi)`
60			`movl $0,8(%esi)`
61			`popl %esi`
62			`leave`
63			`ret`
64
65			`L_more_than_63:`
66			`cmpl $96,%ecx`
67			`jnc L_more_than_95`
68
69			`subb $64,%cl`
70			`movl 8(%esi),%eax /* msl */`
71			`shr %cl,%eax`
72			`xorl %edx,%edx`
73			`movl %eax,(%esi)`
74			`movl %edx,4(%esi)`
75			`movl %edx,8(%esi)`
76			`popl %esi`
77			`leave`
78			`ret`
79
80			`L_more_than_95:`
81			`xorl %eax,%eax`
82			`movl %eax,(%esi)`
83			`movl %eax,4(%esi)`
84			`movl %eax,8(%esi)`
85			`popl %esi`
86			`leave`
87			`ret`

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[/] [or1k/] [trunk/] [uclinux/] [uClinux-2.0.x/] [arch/] [i386/] [math-emu/] [shr_Xsig.S] - Blame information for rev 1767