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 /* This header file includes the inline functions for ARM processors in
12  * the fix point signal processing library.
13  */
14 
15 #ifndef COMMON_AUDIO_SIGNAL_PROCESSING_INCLUDE_SPL_INL_ARMV7_H_
16 #define COMMON_AUDIO_SIGNAL_PROCESSING_INCLUDE_SPL_INL_ARMV7_H_
17 
18 /* TODO(kma): Replace some assembly code with GCC intrinsics
19  * (e.g. __builtin_clz).
20  */
21 
22 /* This function produces result that is not bit exact with that by the generic
23  * C version in some cases, although the former is at least as accurate as the
24  * later.
25  */
WEBRTC_SPL_MUL_16_32_RSFT16(int16_t a,int32_t b)26 static __inline int32_t WEBRTC_SPL_MUL_16_32_RSFT16(int16_t a, int32_t b) {
27   int32_t tmp = 0;
28   __asm __volatile("smulwb %0, %1, %2" : "=r"(tmp) : "r"(b), "r"(a));
29   return tmp;
30 }
31 
WEBRTC_SPL_MUL_16_16(int16_t a,int16_t b)32 static __inline int32_t WEBRTC_SPL_MUL_16_16(int16_t a, int16_t b) {
33   int32_t tmp = 0;
34   __asm __volatile("smulbb %0, %1, %2" : "=r"(tmp) : "r"(a), "r"(b));
35   return tmp;
36 }
37 
38 // TODO(kma): add unit test.
WebRtc_MulAccumW16(int16_t a,int16_t b,int32_t c)39 static __inline int32_t WebRtc_MulAccumW16(int16_t a, int16_t b, int32_t c) {
40   int32_t tmp = 0;
41   __asm __volatile("smlabb %0, %1, %2, %3"
42                    : "=r"(tmp)
43                    : "r"(a), "r"(b), "r"(c));
44   return tmp;
45 }
46 
WebRtcSpl_AddSatW16(int16_t a,int16_t b)47 static __inline int16_t WebRtcSpl_AddSatW16(int16_t a, int16_t b) {
48   int32_t s_sum = 0;
49 
50   __asm __volatile("qadd16 %0, %1, %2" : "=r"(s_sum) : "r"(a), "r"(b));
51 
52   return (int16_t)s_sum;
53 }
54 
WebRtcSpl_AddSatW32(int32_t l_var1,int32_t l_var2)55 static __inline int32_t WebRtcSpl_AddSatW32(int32_t l_var1, int32_t l_var2) {
56   int32_t l_sum = 0;
57 
58   __asm __volatile("qadd %0, %1, %2" : "=r"(l_sum) : "r"(l_var1), "r"(l_var2));
59 
60   return l_sum;
61 }
62 
WebRtcSpl_SubSatW32(int32_t l_var1,int32_t l_var2)63 static __inline int32_t WebRtcSpl_SubSatW32(int32_t l_var1, int32_t l_var2) {
64   int32_t l_sub = 0;
65 
66   __asm __volatile("qsub %0, %1, %2" : "=r"(l_sub) : "r"(l_var1), "r"(l_var2));
67 
68   return l_sub;
69 }
70 
WebRtcSpl_SubSatW16(int16_t var1,int16_t var2)71 static __inline int16_t WebRtcSpl_SubSatW16(int16_t var1, int16_t var2) {
72   int32_t s_sub = 0;
73 
74   __asm __volatile("qsub16 %0, %1, %2" : "=r"(s_sub) : "r"(var1), "r"(var2));
75 
76   return (int16_t)s_sub;
77 }
78 
WebRtcSpl_GetSizeInBits(uint32_t n)79 static __inline int16_t WebRtcSpl_GetSizeInBits(uint32_t n) {
80   int32_t tmp = 0;
81 
82   __asm __volatile("clz %0, %1" : "=r"(tmp) : "r"(n));
83 
84   return (int16_t)(32 - tmp);
85 }
86 
WebRtcSpl_NormW32(int32_t a)87 static __inline int16_t WebRtcSpl_NormW32(int32_t a) {
88   int32_t tmp = 0;
89 
90   if (a == 0) {
91     return 0;
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)
105     return 0;
106 
107   __asm __volatile("clz %0, %1" : "=r"(tmp) : "r"(a));
108 
109   return (int16_t)tmp;
110 }
111 
WebRtcSpl_NormW16(int16_t a)112 static __inline int16_t WebRtcSpl_NormW16(int16_t a) {
113   int32_t tmp = 0;
114   int32_t a_32 = a;
115 
116   if (a_32 == 0) {
117     return 0;
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  // COMMON_AUDIO_SIGNAL_PROCESSING_INCLUDE_SPL_INL_ARMV7_H_
137