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 ----------------------------------------------------------------------------*/ 141 142 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
