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1 /* ------------------------------------------------------------------
2  * Copyright (C) 1998-2009 PacketVideo
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
13  * express or implied.
14  * See the License for the specific language governing permissions
15  * and limitations under the License.
16  * -------------------------------------------------------------------
17  */
18 /****************************************************************************************
19 Portions of this file are derived from the following 3GPP standard:
20 
21     3GPP TS 26.073
22     ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec
23     Available from http://www.3gpp.org
24 
25 (C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC)
26 Permission to distribute, modify and use this file under the standard license
27 terms listed above has been obtained from the copyright holder.
28 ****************************************************************************************/
29 /*
30 ------------------------------------------------------------------------------
31  INPUT AND OUTPUT DEFINITIONS
32 
33  Inputs:
34     hi = 16 bit signed integer (Word16) whose value falls in
35          the range : 0x8000 <= hi <= 0x7fff.
36     lo = 16 bit signed integer (Word16) whose value falls in
37          the range : 0x8000 <= lo <= 0x7fff.
38 
39  Outputs:
40     pOverflow = 1 if overflow happens in a math function called by this function.
41     L_out = 32-bit result of (hi<<16 + lo<<1).
42 
43  Returns:
44     None
45 
46  Local Stores Modified:
47     None
48 
49  Global Stores Modified:
50         None
51 
52 ------------------------------------------------------------------------------
53  FUNCTION DESCRIPTION
54 
55  This function composes a 32 bit integer from two 16 bit double precision
56  format (DPF) numbers hi and lo by the following operation:
57  1. Deposit hi into the 16 MS bits of the 32 bit output L_out.
58  2. Shift lo left by 1.
59  3. Add results from 1 and 2 with saturation to return the 32 bit result
60     L_out.
61 
62 ------------------------------------------------------------------------------
63  REQUIREMENTS
64 
65  None
66 
67 ------------------------------------------------------------------------------
68  REFERENCES
69 
70  [1] oper_32b.c, ETS Version 2.0.0, February 8, 1999
71 
72 ------------------------------------------------------------------------------
73  PSEUDO-CODE
74 
75 ------------------------------------------------------------------------------
76  RESOURCES USED
77    When the code is written for a specific target processor the
78      the resources used should be documented below.
79 
80  STACK USAGE: [stack count for this module] + [variable to represent
81           stack usage for each subroutine called]
82 
83      where: [stack usage variable] = stack usage for [subroutine
84          name] (see [filename].ext)
85 
86  DATA MEMORY USED: x words
87 
88  PROGRAM MEMORY USED: x words
89 
90  CLOCK CYCLES: [cycle count equation for this module] + [variable
91            used to represent cycle count for each subroutine
92            called]
93 
94      where: [cycle count variable] = cycle count for [subroutine
95         name] (see [filename].ext)
96 
97 ------------------------------------------------------------------------------
98 */
99 
100 
101 /*----------------------------------------------------------------------------
102 ; INCLUDES
103 ----------------------------------------------------------------------------*/
104 #include "typedef.h"
105 #include "l_comp.h"
106 #include "basic_op.h"
107 /*----------------------------------------------------------------------------
108 ; MACROS
109 ; Define module specific macros here
110 ----------------------------------------------------------------------------*/
111 
112 /*----------------------------------------------------------------------------
113 ; DEFINES
114 ; Include all pre-processor statements here. Include conditional
115 ; compile variables also.
116 ----------------------------------------------------------------------------*/
117 
118 /*----------------------------------------------------------------------------
119 ; LOCAL FUNCTION DEFINITIONS
120 ; Function Prototype declaration
121 ----------------------------------------------------------------------------*/
122 
123 /*----------------------------------------------------------------------------
124 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS
125 ; Variable declaration - defined here and used outside this module
126 ----------------------------------------------------------------------------*/
127 
128 /*----------------------------------------------------------------------------
129 ; EXTERNAL FUNCTION REFERENCES
130 ; Declare functions defined elsewhere and referenced in this module
131 ----------------------------------------------------------------------------*/
132 
133 /*----------------------------------------------------------------------------
134 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
135 ; Declare variables used in this module but defined elsewhere
136 ----------------------------------------------------------------------------*/
137 
138 /*----------------------------------------------------------------------------
139 ; FUNCTION CODE
140 ----------------------------------------------------------------------------*/
141 
L_Comp(Word16 hi,Word16 lo,Flag * pOverflow)142 Word32 L_Comp(Word16 hi, Word16 lo, Flag *pOverflow)
143 {
144 
145     /*----------------------------------------------------------------------------
146     ; Define all local variables
147     ----------------------------------------------------------------------------*/
148     Word32 L_32;
149     Word32 temp32;
150     /*----------------------------------------------------------------------------
151     ; Function body here
152     ----------------------------------------------------------------------------*/
153 
154     L_32 = L_deposit_h(hi);
155 
156     temp32 = L_mac(L_32, lo, 1, pOverflow);
157     /*----------------------------------------------------------------------------
158     ; Return nothing or data or data pointer
159     ----------------------------------------------------------------------------*/
160 
161     return (temp32);       /* = hi<<16 + lo<<1 */
162 }
163