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[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [libgcc/] [config/] [rl78/] [lshrsi3.S] - Blame information for rev 751

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;   Copyright (C) 2011 Free Software Foundation, Inc.
;   Contributed by Red Hat.
;
; This file is free software; you can redistribute it and/or modify it
; under the terms of the GNU General Public License as published by the
; Free Software Foundation; either version 3, or (at your option) any
; later version.
;
; This file is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
; General Public License for more details.
;
; Under Section 7 of GPL version 3, you are granted additional
; permissions described in the GCC Runtime Library Exception, version
; 3.1, as published by the Free Software Foundation.
;
; You should have received a copy of the GNU General Public License and
; a copy of the GCC Runtime Library Exception along with this program;
; see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
; .
 
r8      =       0xffef0
r16     =       0xffee8
r9      =       0xffef1
r17     =       0xffee9
r10     =       0xffef2
r18     =       0xffeea
r11     =       0xffef3
r19     =       0xffeeb
r12     =       0xffef4
r20     =       0xffeec
r13     =       0xffef5
r21     =       0xffeed
r14     =       0xffef6
r22     =       0xffeee
r15     =       0xffef7
r23     =       0xffeef
 
        .text
        .global ___lshrsi3
        .type   ___lshrsi3, @function
___lshrsi3:
 
        ;; input:
        ;;
        ;; [zero]
        ;; [count]   <= $sp+8
        ;; [in MSB]
        ;; [in]
        ;; [in]
        ;; [in LSB]  <- $sp+4
 
        ;; output:
        ;;
        ;; [r8..r11] result
 
        ;; registers:
        ;;
        ;; AX - temp for shift/rotate
        ;; B  - count
 
        mov     a, [sp+8]       ; A now contains the count
 
        cmp     a, #0x20
        bc      $.Lcount_is_normal
 
        ;; count is out of bounds, just return zero.
        movw    r8, #0
        movw    r10, #0
        ret
 
.Lcount_is_normal:
        cmp0    a
        bnz     $.Lcount_is_nonzero
 
        ;; count is zero, just copy IN to OUT
        movw    ax, [sp+4]
        movw    r8, ax
        movw    ax, [sp+6]
        movw    r10, ax
        ret
 
.Lcount_is_nonzero:
        mov     b, a            ; B now contains the count also
        bf      a.4, $.Lcount_lt_16
 
        ;; count >= 16, shift 16 at a time.
        movw    r10, #0
        movw    ax, [sp+6]
        movw    r8, ax
        mov     a, b
        and     a, #0x0f
        sknz
        ret
 
        mov     b, a            ; B now contains the remaining count
        inc     b
        br      $.Lloop_top
 
.Lcount_lt_16:
        ;; count is nonzero.  Do one
        movw    ax, [sp+6]
        shrw    ax,1
        movw    r10, ax
        mov     a, [sp+5]
        rorc    a,1
        mov     r9, a
        mov     a, [sp+4]
        rorc    a,1
        mov     r8, a
 
        ;; we did one shift above; do as many more as we need now.
.Lloop_top:
        dec     b
        sknz
        ret
 
        movw    ax, r10
        shrw    ax,1
        movw    r10, ax
        mov     a, r9
        rorc    a,1
        mov     r9, a
        mov     a, r8
        rorc    a,1
        mov     r8, a
 
        br      $.Lloop_top
 
        .size   ___lshrsi3, .-___lshrsi3

Line No.	Rev	Author	Line
1	734	jeremybenn	`; Copyright (C) 2011 Free Software Foundation, Inc.`
2			`; Contributed by Red Hat.`
3			`;`
4			`; This file is free software; you can redistribute it and/or modify it`
5			`; under the terms of the GNU General Public License as published by the`
6			`; Free Software Foundation; either version 3, or (at your option) any`
7			`; later version.`
8			`;`
9			`; This file is distributed in the hope that it will be useful, but`
10			`; WITHOUT ANY WARRANTY; without even the implied warranty of`
11			`; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU`
12			`; General Public License for more details.`
13			`;`
14			`; Under Section 7 of GPL version 3, you are granted additional`
15			`; permissions described in the GCC Runtime Library Exception, version`
16			`; 3.1, as published by the Free Software Foundation.`
17			`;`
18			`; You should have received a copy of the GNU General Public License and`
19			`; a copy of the GCC Runtime Library Exception along with this program;`
20			`; see the files COPYING3 and COPYING.RUNTIME respectively. If not, see`
21			`; .`
22
23			`r8 = 0xffef0`
24			`r16 = 0xffee8`
25			`r9 = 0xffef1`
26			`r17 = 0xffee9`
27			`r10 = 0xffef2`
28			`r18 = 0xffeea`
29			`r11 = 0xffef3`
30			`r19 = 0xffeeb`
31			`r12 = 0xffef4`
32			`r20 = 0xffeec`
33			`r13 = 0xffef5`
34			`r21 = 0xffeed`
35			`r14 = 0xffef6`
36			`r22 = 0xffeee`
37			`r15 = 0xffef7`
38			`r23 = 0xffeef`
39
40			`.text`
41			`.global ___lshrsi3`
42			`.type ___lshrsi3, @function`
43			`___lshrsi3:`
44
45			`;; input:`
46			`;;`
47			`;; [zero]`
48			`;; [count] <= $sp+8`
49			`;; [in MSB]`
50			`;; [in]`
51			`;; [in]`
52			`;; [in LSB] <- $sp+4`
53
54			`;; output:`
55			`;;`
56			`;; [r8..r11] result`
57
58			`;; registers:`
59			`;;`
60			`;; AX - temp for shift/rotate`
61			`;; B - count`
62
63			`mov a, [sp+8] ; A now contains the count`
64
65			`cmp a, #0x20`
66			`bc $.Lcount_is_normal`
67
68			`;; count is out of bounds, just return zero.`
69			`movw r8, #0`
70			`movw r10, #0`
71			`ret`
72
73			`.Lcount_is_normal:`
74			`cmp0 a`
75			`bnz $.Lcount_is_nonzero`
76
77			`;; count is zero, just copy IN to OUT`
78			`movw ax, [sp+4]`
79			`movw r8, ax`
80			`movw ax, [sp+6]`
81			`movw r10, ax`
82			`ret`
83
84			`.Lcount_is_nonzero:`
85			`mov b, a ; B now contains the count also`
86			`bf a.4, $.Lcount_lt_16`
87
88			`;; count >= 16, shift 16 at a time.`
89			`movw r10, #0`
90			`movw ax, [sp+6]`
91			`movw r8, ax`
92			`mov a, b`
93			`and a, #0x0f`
94			`sknz`
95			`ret`
96
97			`mov b, a ; B now contains the remaining count`
98			`inc b`
99			`br $.Lloop_top`
100
101			`.Lcount_lt_16:`
102			`;; count is nonzero. Do one`
103			`movw ax, [sp+6]`
104			`shrw ax,1`
105			`movw r10, ax`
106			`mov a, [sp+5]`
107			`rorc a,1`
108			`mov r9, a`
109			`mov a, [sp+4]`
110			`rorc a,1`
111			`mov r8, a`
112
113			`;; we did one shift above; do as many more as we need now.`
114			`.Lloop_top:`
115			`dec b`
116			`sknz`
117			`ret`
118
119			`movw ax, r10`
120			`shrw ax,1`
121			`movw r10, ax`
122			`mov a, r9`
123			`rorc a,1`
124			`mov r9, a`
125			`mov a, r8`
126			`rorc a,1`
127			`mov r8, a`
128
129			`br $.Lloop_top`
130
131			`.size ___lshrsi3, .-___lshrsi3`

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[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [libgcc/] [config/] [rl78/] [lshrsi3.S] - Blame information for rev 751