fixed_arm4.h revision 98913fed6520d8849fb2e246be943e04474aefa4 
1/* Copyright (C) 2004 Jean-Marc Valin */
2/**
3   @file fixed_arm4.h
4   @brief ARM4 fixed-point operations
5*/
6/*
7   Redistribution and use in source and binary forms, with or without
8   modification, are permitted provided that the following conditions
9   are met:
10
11   - Redistributions of source code must retain the above copyright
12   notice, this list of conditions and the following disclaimer.
13
14   - Redistributions in binary form must reproduce the above copyright
15   notice, this list of conditions and the following disclaimer in the
16   documentation and/or other materials provided with the distribution.
17
18   - Neither the name of the Xiph.org Foundation nor the names of its
19   contributors may be used to endorse or promote products derived from
20   this software without specific prior written permission.
21
22   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
26   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
29   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33*/
34
35#ifndef FIXED_ARM4_H
36#define FIXED_ARM4_H
37
38#undef MULT16_32_Q14
39static inline spx_word32_t MULT16_32_Q14(spx_word16_t x, spx_word32_t y) {
40  int res;
41  int dummy;
42  asm (
43        "smull  %0,%1,%2,%3 \n\t"
44        "mov %0, %0, lsr #14 \n\t"
45        "add %0, %0, %1, lsl #18 \n\t"
46   : "=&r"(res), "=&r" (dummy)
47   : "r"(y),"r"((int)x));
48  return(res);
49}
50
51#undef MULT16_32_Q15
52static inline spx_word32_t MULT16_32_Q15(spx_word16_t x, spx_word32_t y) {
53  int res;
54  int dummy;
55  asm (
56        "smull  %0,%1,%2,%3 \n\t"
57        "mov %0, %0, lsr #15 \n\t"
58        "add %0, %0, %1, lsl #17 \n\t"
59   : "=&r"(res), "=&r" (dummy)
60   : "r"(y),"r"((int)x));
61  return(res);
62}
63
64#undef DIV32_16
65static inline short DIV32_16(int a, int b)
66{
67   int res=0;
68   int dead1, dead2, dead3, dead4, dead5;
69   __asm__ __volatile__ (
70         "\teor %5, %0, %1\n"
71         "\tmovs %4, %0\n"
72         "\trsbmi %0, %0, #0 \n"
73         "\tmovs %4, %1\n"
74         "\trsbmi %1, %1, #0 \n"
75         "\tmov %4, #1\n"
76
77         "\tsubs %3, %0, %1, asl #14 \n"
78         "\tmovpl %0, %3 \n"
79         "\torrpl %2, %2, %4, asl #14 \n"
80
81         "\tsubs %3, %0, %1, asl #13 \n"
82         "\tmovpl %0, %3 \n"
83         "\torrpl %2, %2, %4, asl #13 \n"
84
85         "\tsubs %3, %0, %1, asl #12 \n"
86         "\tmovpl %0, %3 \n"
87         "\torrpl %2, %2, %4, asl #12 \n"
88
89         "\tsubs %3, %0, %1, asl #11 \n"
90         "\tmovpl %0, %3 \n"
91         "\torrpl %2, %2, %4, asl #11 \n"
92
93         "\tsubs %3, %0, %1, asl #10 \n"
94         "\tmovpl %0, %3 \n"
95         "\torrpl %2, %2, %4, asl #10 \n"
96
97         "\tsubs %3, %0, %1, asl #9 \n"
98         "\tmovpl %0, %3 \n"
99         "\torrpl %2, %2, %4, asl #9 \n"
100
101         "\tsubs %3, %0, %1, asl #8 \n"
102         "\tmovpl %0, %3 \n"
103         "\torrpl %2, %2, %4, asl #8 \n"
104
105         "\tsubs %3, %0, %1, asl #7 \n"
106         "\tmovpl %0, %3 \n"
107         "\torrpl %2, %2, %4, asl #7 \n"
108
109         "\tsubs %3, %0, %1, asl #6 \n"
110         "\tmovpl %0, %3 \n"
111         "\torrpl %2, %2, %4, asl #6 \n"
112
113         "\tsubs %3, %0, %1, asl #5 \n"
114         "\tmovpl %0, %3 \n"
115         "\torrpl %2, %2, %4, asl #5 \n"
116
117         "\tsubs %3, %0, %1, asl #4 \n"
118         "\tmovpl %0, %3 \n"
119         "\torrpl %2, %2, %4, asl #4 \n"
120
121         "\tsubs %3, %0, %1, asl #3 \n"
122         "\tmovpl %0, %3 \n"
123         "\torrpl %2, %2, %4, asl #3 \n"
124
125         "\tsubs %3, %0, %1, asl #2 \n"
126         "\tmovpl %0, %3 \n"
127         "\torrpl %2, %2, %4, asl #2 \n"
128
129         "\tsubs %3, %0, %1, asl #1 \n"
130         "\tmovpl %0, %3 \n"
131         "\torrpl %2, %2, %4, asl #1 \n"
132
133         "\tsubs %3, %0, %1 \n"
134         "\tmovpl %0, %3 \n"
135         "\torrpl %2, %2, %4 \n"
136
137         "\tmovs %5, %5, lsr #31 \n"
138         "\trsbne %2, %2, #0 \n"
139   : "=r" (dead1), "=r" (dead2), "=r" (res),
140   "=r" (dead3), "=r" (dead4), "=r" (dead5)
141   : "0" (a), "1" (b), "2" (res)
142   : "cc"
143                        );
144   return res;
145}
146
147
148#endif
149