xref: /aosp_15_r20/external/libopus/celt/fixed_generic.h (revision a58d3d2adb790c104798cd88c8a3aff4fa8b82cc)
1 /* Copyright (C) 2007-2009 Xiph.Org Foundation
2    Copyright (C) 2003-2008 Jean-Marc Valin
3    Copyright (C) 2007-2008 CSIRO */
4 /**
5    @file fixed_generic.h
6    @brief Generic fixed-point operations
7 */
8 /*
9    Redistribution and use in source and binary forms, with or without
10    modification, are permitted provided that the following conditions
11    are met:
12 
13    - Redistributions of source code must retain the above copyright
14    notice, this list of conditions and the following disclaimer.
15 
16    - Redistributions in binary form must reproduce the above copyright
17    notice, this list of conditions and the following disclaimer in the
18    documentation and/or other materials provided with the distribution.
19 
20    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
24    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32 
33 #ifndef FIXED_GENERIC_H
34 #define FIXED_GENERIC_H
35 
36 /** Multiply a 16-bit signed value by a 16-bit unsigned value. The result is a 32-bit signed value */
37 #define MULT16_16SU(a,b) ((opus_val32)(opus_val16)(a)*(opus_val32)(opus_uint16)(b))
38 
39 /** 16x32 multiplication, followed by a 16-bit shift right. Results fits in 32 bits */
40 #if OPUS_FAST_INT64
41 #define MULT16_32_Q16(a,b) ((opus_val32)SHR((opus_int64)((opus_val16)(a))*(b),16))
42 #else
43 #define MULT16_32_Q16(a,b) ADD32(MULT16_16((a),SHR((b),16)), SHR(MULT16_16SU((a),((b)&0x0000ffff)),16))
44 #endif
45 
46 /** 16x32 multiplication, followed by a 16-bit shift right (round-to-nearest). Results fits in 32 bits */
47 #if OPUS_FAST_INT64
48 #define MULT16_32_P16(a,b) ((opus_val32)PSHR((opus_int64)((opus_val16)(a))*(b),16))
49 #else
50 #define MULT16_32_P16(a,b) ADD32(MULT16_16((a),SHR((b),16)), PSHR(MULT16_16SU((a),((b)&0x0000ffff)),16))
51 #endif
52 
53 /** 16x32 multiplication, followed by a 15-bit shift right. Results fits in 32 bits */
54 #if OPUS_FAST_INT64
55 #define MULT16_32_Q15(a,b) ((opus_val32)SHR((opus_int64)((opus_val16)(a))*(b),15))
56 #else
57 #define MULT16_32_Q15(a,b) ADD32(SHL(MULT16_16((a),SHR((b),16)),1), SHR(MULT16_16SU((a),((b)&0x0000ffff)),15))
58 #endif
59 
60 /** 32x32 multiplication, followed by a 16-bit shift right. Results fits in 32 bits */
61 #if OPUS_FAST_INT64
62 #define MULT32_32_Q16(a,b) ((opus_val32)SHR((opus_int64)(a)*(opus_int64)(b),16))
63 #else
64 #define MULT32_32_Q16(a,b) (ADD32(ADD32(ADD32((opus_val32)(SHR32(((opus_uint32)((a)&0x0000ffff)*(opus_uint32)((b)&0x0000ffff)),16)), MULT16_16SU(SHR32(a,16),((b)&0x0000ffff))), MULT16_16SU(SHR32(b,16),((a)&0x0000ffff))), SHL32(MULT16_16(SHR32(a,16),SHR32(b,16)),16)))
65 #endif
66 
67 /** 32x32 multiplication, followed by a 31-bit shift right. Results fits in 32 bits */
68 #if OPUS_FAST_INT64
69 #define MULT32_32_Q31(a,b) ((opus_val32)SHR((opus_int64)(a)*(opus_int64)(b),31))
70 #else
71 #define MULT32_32_Q31(a,b) ADD32(ADD32(SHL(MULT16_16(SHR((a),16),SHR((b),16)),1), SHR(MULT16_16SU(SHR((a),16),((b)&0x0000ffff)),15)), SHR(MULT16_16SU(SHR((b),16),((a)&0x0000ffff)),15))
72 #endif
73 
74 /** Compile-time conversion of float constant to 16-bit value */
75 #define QCONST16(x,bits) ((opus_val16)(.5+(x)*(((opus_val32)1)<<(bits))))
76 
77 /** Compile-time conversion of float constant to 32-bit value */
78 #define QCONST32(x,bits) ((opus_val32)(.5+(x)*(((opus_val32)1)<<(bits))))
79 
80 /** Negate a 16-bit value */
81 #define NEG16(x) (-(x))
82 /** Negate a 32-bit value */
83 #define NEG32(x) (-(x))
84 
85 /** Change a 32-bit value into a 16-bit value. The value is assumed to fit in 16-bit, otherwise the result is undefined */
86 #define EXTRACT16(x) ((opus_val16)(x))
87 /** Change a 16-bit value into a 32-bit value */
88 #define EXTEND32(x) ((opus_val32)(x))
89 
90 /** Arithmetic shift-right of a 16-bit value */
91 #define SHR16(a,shift) ((a) >> (shift))
92 /** Arithmetic shift-left of a 16-bit value */
93 #define SHL16(a,shift) ((opus_int16)((opus_uint16)(a)<<(shift)))
94 /** Arithmetic shift-right of a 32-bit value */
95 #define SHR32(a,shift) ((a) >> (shift))
96 /** Arithmetic shift-left of a 32-bit value */
97 #define SHL32(a,shift) ((opus_int32)((opus_uint32)(a)<<(shift)))
98 
99 /** 32-bit arithmetic shift right with rounding-to-nearest instead of rounding down */
100 #define PSHR32(a,shift) (SHR32((a)+((EXTEND32(1)<<((shift))>>1)),shift))
101 /** 32-bit arithmetic shift right where the argument can be negative */
102 #define VSHR32(a, shift) (((shift)>0) ? SHR32(a, shift) : SHL32(a, -(shift)))
103 
104 /** "RAW" macros, should not be used outside of this header file */
105 #define SHR(a,shift) ((a) >> (shift))
106 #define SHL(a,shift) SHL32(a,shift)
107 #define PSHR(a,shift) (SHR((a)+((EXTEND32(1)<<((shift))>>1)),shift))
108 #define SATURATE(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))
109 
110 #define SATURATE16(x) (EXTRACT16((x)>32767 ? 32767 : (x)<-32768 ? -32768 : (x)))
111 
112 /** Shift by a and round-to-nearest 32-bit value. Result is a 16-bit value */
113 #define ROUND16(x,a) (EXTRACT16(PSHR32((x),(a))))
114 /** Shift by a and round-to-nearest 32-bit value. Result is a saturated 16-bit value */
115 #define SROUND16(x,a) EXTRACT16(SATURATE(PSHR32(x,a), 32767));
116 
117 /** Divide by two */
118 #define HALF16(x)  (SHR16(x,1))
119 #define HALF32(x)  (SHR32(x,1))
120 
121 /** Add two 16-bit values */
122 #define ADD16(a,b) ((opus_val16)((opus_val16)(a)+(opus_val16)(b)))
123 /** Subtract two 16-bit values */
124 #define SUB16(a,b) ((opus_val16)(a)-(opus_val16)(b))
125 /** Add two 32-bit values */
126 #define ADD32(a,b) ((opus_val32)(a)+(opus_val32)(b))
127 /** Subtract two 32-bit values */
128 #define SUB32(a,b) ((opus_val32)(a)-(opus_val32)(b))
129 
130 /** Add two 32-bit values, ignore any overflows */
131 #define ADD32_ovflw(a,b) ((opus_val32)((opus_uint32)(a)+(opus_uint32)(b)))
132 /** Subtract two 32-bit values, ignore any overflows */
133 #define SUB32_ovflw(a,b) ((opus_val32)((opus_uint32)(a)-(opus_uint32)(b)))
134 /* Avoid MSVC warning C4146: unary minus operator applied to unsigned type */
135 /** Negate 32-bit value, ignore any overflows */
136 #define NEG32_ovflw(a) ((opus_val32)(0-(opus_uint32)(a)))
137 
138 /** 16x16 multiplication where the result fits in 16 bits */
139 #define MULT16_16_16(a,b)     ((((opus_val16)(a))*((opus_val16)(b))))
140 
141 /** 32x32 multiplication where the result fits in 32 bits */
142 #define MULT32_32_32(a,b)     ((((opus_val32)(a))*((opus_val32)(b))))
143 
144 /* (opus_val32)(opus_val16) gives TI compiler a hint that it's 16x16->32 multiply */
145 /** 16x16 multiplication where the result fits in 32 bits */
146 #define MULT16_16(a,b)     (((opus_val32)(opus_val16)(a))*((opus_val32)(opus_val16)(b)))
147 
148 /** 16x16 multiply-add where the result fits in 32 bits */
149 #define MAC16_16(c,a,b) (ADD32((c),MULT16_16((a),(b))))
150 /** 16x32 multiply, followed by a 15-bit shift right and 32-bit add.
151     b must fit in 31 bits.
152     Result fits in 32 bits. */
153 #define MAC16_32_Q15(c,a,b) ADD32((c),ADD32(MULT16_16((a),SHR((b),15)), SHR(MULT16_16((a),((b)&0x00007fff)),15)))
154 
155 /** 16x32 multiplication, followed by a 16-bit shift right and 32-bit add.
156     Results fits in 32 bits */
157 #define MAC16_32_Q16(c,a,b) ADD32((c),ADD32(MULT16_16((a),SHR((b),16)), SHR(MULT16_16SU((a),((b)&0x0000ffff)),16)))
158 
159 #define MULT16_16_Q11_32(a,b) (SHR(MULT16_16((a),(b)),11))
160 #define MULT16_16_Q11(a,b) (SHR(MULT16_16((a),(b)),11))
161 #define MULT16_16_Q13(a,b) (SHR(MULT16_16((a),(b)),13))
162 #define MULT16_16_Q14(a,b) (SHR(MULT16_16((a),(b)),14))
163 #define MULT16_16_Q15(a,b) (SHR(MULT16_16((a),(b)),15))
164 
165 #define MULT16_16_P13(a,b) (SHR(ADD32(4096,MULT16_16((a),(b))),13))
166 #define MULT16_16_P14(a,b) (SHR(ADD32(8192,MULT16_16((a),(b))),14))
167 #define MULT16_16_P15(a,b) (SHR(ADD32(16384,MULT16_16((a),(b))),15))
168 
169 /** Divide a 32-bit value by a 16-bit value. Result fits in 16 bits */
170 #define DIV32_16(a,b) ((opus_val16)(((opus_val32)(a))/((opus_val16)(b))))
171 
172 /** Divide a 32-bit value by a 32-bit value. Result fits in 32 bits */
173 #define DIV32(a,b) (((opus_val32)(a))/((opus_val32)(b)))
174 
175 #if defined(MIPSr1_ASM)
176 #include "mips/fixed_generic_mipsr1.h"
177 #endif
178 
SIG2WORD16_generic(celt_sig x)179 static OPUS_INLINE opus_val16 SIG2WORD16_generic(celt_sig x)
180 {
181    x = PSHR32(x, SIG_SHIFT);
182    x = MAX32(x, -32768);
183    x = MIN32(x, 32767);
184    return EXTRACT16(x);
185 }
186 #define SIG2WORD16(x) (SIG2WORD16_generic(x))
187 
188 #endif
189