1 /*
2  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 
12 /* This header file includes the inline functions for ARM processors in
13  * the fix point signal processing library.
14  */
15 
16 #ifndef WEBRTC_SPL_SPL_INL_ARMV7_H_
17 #define WEBRTC_SPL_SPL_INL_ARMV7_H_
18 
19 /* TODO(kma): Replace some assembly code with GCC intrinsics
20  * (e.g. __builtin_clz).
21  */
22 
23 /* This function produces result that is not bit exact with that by the generic
24  * C version in some cases, although the former is at least as accurate as the
25  * later.
26  */
WEBRTC_SPL_MUL_16_32_RSFT16(int16_t a,int32_t b)27 static __inline int32_t WEBRTC_SPL_MUL_16_32_RSFT16(int16_t a, int32_t b) {
28   int32_t tmp = 0;
29   __asm __volatile ("smulwb %0, %1, %2":"=r"(tmp):"r"(b), "r"(a));
30   return tmp;
31 }
32 
WEBRTC_SPL_MUL_16_16(int16_t a,int16_t b)33 static __inline int32_t WEBRTC_SPL_MUL_16_16(int16_t a, int16_t b) {
34   int32_t tmp = 0;
35   __asm __volatile ("smulbb %0, %1, %2":"=r"(tmp):"r"(a), "r"(b));
36   return tmp;
37 }
38 
39 // TODO(kma): add unit test.
WebRtc_MulAccumW16(int16_t a,int16_t b,int32_t c)40 static __inline int32_t WebRtc_MulAccumW16(int16_t a, int16_t b, int32_t c) {
41   int32_t tmp = 0;
42   __asm __volatile ("smlabb %0, %1, %2, %3":"=r"(tmp):"r"(a), "r"(b), "r"(c));
43   return tmp;
44 }
45 
WebRtcSpl_AddSatW16(int16_t a,int16_t b)46 static __inline int16_t WebRtcSpl_AddSatW16(int16_t a, int16_t b) {
47   int32_t s_sum = 0;
48 
49   __asm __volatile ("qadd16 %0, %1, %2":"=r"(s_sum):"r"(a), "r"(b));
50 
51   return (int16_t) s_sum;
52 }
53 
WebRtcSpl_AddSatW32(int32_t l_var1,int32_t l_var2)54 static __inline int32_t WebRtcSpl_AddSatW32(int32_t l_var1, int32_t l_var2) {
55   int32_t l_sum = 0;
56 
57   __asm __volatile ("qadd %0, %1, %2":"=r"(l_sum):"r"(l_var1), "r"(l_var2));
58 
59   return l_sum;
60 }
61 
WebRtcSpl_SubSatW32(int32_t l_var1,int32_t l_var2)62 static __inline int32_t WebRtcSpl_SubSatW32(int32_t l_var1, int32_t l_var2) {
63   int32_t l_sub = 0;
64 
65   __asm __volatile ("qsub %0, %1, %2":"=r"(l_sub):"r"(l_var1), "r"(l_var2));
66 
67   return l_sub;
68 }
69 
WebRtcSpl_SubSatW16(int16_t var1,int16_t var2)70 static __inline int16_t WebRtcSpl_SubSatW16(int16_t var1, int16_t var2) {
71   int32_t s_sub = 0;
72 
73   __asm __volatile ("qsub16 %0, %1, %2":"=r"(s_sub):"r"(var1), "r"(var2));
74 
75   return (int16_t)s_sub;
76 }
77 
WebRtcSpl_GetSizeInBits(uint32_t n)78 static __inline int16_t WebRtcSpl_GetSizeInBits(uint32_t n) {
79   int32_t tmp = 0;
80 
81   __asm __volatile ("clz %0, %1":"=r"(tmp):"r"(n));
82 
83   return (int16_t)(32 - tmp);
84 }
85 
WebRtcSpl_NormW32(int32_t a)86 static __inline int16_t WebRtcSpl_NormW32(int32_t a) {
87   int32_t tmp = 0;
88 
89   if (a == 0) {
90     return 0;
91   }
92   else if (a < 0) {
93     a ^= 0xFFFFFFFF;
94   }
95 
96   __asm __volatile ("clz %0, %1":"=r"(tmp):"r"(a));
97 
98   return (int16_t)(tmp - 1);
99 }
100 
WebRtcSpl_NormU32(uint32_t a)101 static __inline int16_t WebRtcSpl_NormU32(uint32_t a) {
102   int tmp = 0;
103 
104   if (a == 0) return 0;
105 
106   __asm __volatile ("clz %0, %1":"=r"(tmp):"r"(a));
107 
108   return (int16_t)tmp;
109 }
110 
WebRtcSpl_NormW16(int16_t a)111 static __inline int16_t WebRtcSpl_NormW16(int16_t a) {
112   int32_t tmp = 0;
113   int32_t a_32 = a;
114 
115   if (a_32 == 0) {
116     return 0;
117   }
118   else if (a_32 < 0) {
119     a_32 ^= 0xFFFFFFFF;
120   }
121 
122   __asm __volatile ("clz %0, %1":"=r"(tmp):"r"(a_32));
123 
124   return (int16_t)(tmp - 17);
125 }
126 
127 // TODO(kma): add unit test.
WebRtcSpl_SatW32ToW16(int32_t value32)128 static __inline int16_t WebRtcSpl_SatW32ToW16(int32_t value32) {
129   int32_t out = 0;
130 
131   __asm __volatile ("ssat %0, #16, %1" : "=r"(out) : "r"(value32));
132 
133   return (int16_t)out;
134 }
135 
136 #endif  // WEBRTC_SPL_SPL_INL_ARMV7_H_
137