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| Rev | Author | Line No. | Line |
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| 2 | mjames | 1 | /* ---------------------------------------------------------------------- |
| 2 | * Project: CMSIS DSP Library |
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| 3 | * Title: arm_q15_to_q31.c |
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| 4 | * Description: Converts the elements of the Q15 vector to Q31 vector |
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| 5 | * |
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| 6 | * $Date: 27. January 2017 |
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| 7 | * $Revision: V.1.5.1 |
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| 8 | * |
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| 9 | * Target Processor: Cortex-M cores |
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| 10 | * -------------------------------------------------------------------- */ |
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| 11 | /* |
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| 12 | * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved. |
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| 13 | * |
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| 14 | * SPDX-License-Identifier: Apache-2.0 |
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| 15 | * |
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| 16 | * Licensed under the Apache License, Version 2.0 (the License); you may |
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| 17 | * not use this file except in compliance with the License. |
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| 18 | * You may obtain a copy of the License at |
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| 19 | * |
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| 20 | * www.apache.org/licenses/LICENSE-2.0 |
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| 21 | * |
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| 22 | * Unless required by applicable law or agreed to in writing, software |
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| 23 | * distributed under the License is distributed on an AS IS BASIS, WITHOUT |
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| 24 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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| 25 | * See the License for the specific language governing permissions and |
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| 26 | * limitations under the License. |
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| 27 | */ |
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| 28 | |||
| 29 | #include "arm_math.h" |
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| 30 | |||
| 31 | /** |
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| 32 | * @ingroup groupSupport |
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| 33 | */ |
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| 34 | |||
| 35 | /** |
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| 36 | * @addtogroup q15_to_x |
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| 37 | * @{ |
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| 38 | */ |
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| 39 | |||
| 40 | /** |
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| 41 | * @brief Converts the elements of the Q15 vector to Q31 vector. |
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| 42 | * @param[in] *pSrc points to the Q15 input vector |
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| 43 | * @param[out] *pDst points to the Q31 output vector |
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| 44 | * @param[in] blockSize length of the input vector |
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| 45 | * @return none. |
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| 46 | * |
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| 47 | * \par Description: |
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| 48 | * |
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| 49 | * The equation used for the conversion process is: |
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| 50 | * |
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| 51 | * <pre> |
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| 52 | * pDst[n] = (q31_t) pSrc[n] << 16; 0 <= n < blockSize. |
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| 53 | * </pre> |
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| 54 | * |
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| 55 | */ |
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| 56 | |||
| 57 | |||
| 58 | void arm_q15_to_q31( |
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| 59 | q15_t * pSrc, |
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| 60 | q31_t * pDst, |
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| 61 | uint32_t blockSize) |
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| 62 | { |
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| 63 | q15_t *pIn = pSrc; /* Src pointer */ |
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| 64 | uint32_t blkCnt; /* loop counter */ |
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| 65 | |||
| 66 | #if defined (ARM_MATH_DSP) |
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| 67 | |||
| 68 | /* Run the below code for Cortex-M4 and Cortex-M3 */ |
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| 69 | q31_t in1, in2; |
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| 70 | q31_t out1, out2, out3, out4; |
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| 71 | |||
| 72 | /*loop Unrolling */ |
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| 73 | blkCnt = blockSize >> 2U; |
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| 74 | |||
| 75 | /* First part of the processing with loop unrolling. Compute 4 outputs at a time. |
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| 76 | ** a second loop below computes the remaining 1 to 3 samples. */ |
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| 77 | while (blkCnt > 0U) |
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| 78 | { |
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| 79 | /* C = (q31_t)A << 16 */ |
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| 80 | /* convert from q15 to q31 and then store the results in the destination buffer */ |
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| 81 | in1 = *__SIMD32(pIn)++; |
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| 82 | in2 = *__SIMD32(pIn)++; |
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| 83 | |||
| 84 | #ifndef ARM_MATH_BIG_ENDIAN |
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| 85 | |||
| 86 | /* extract lower 16 bits to 32 bit result */ |
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| 87 | out1 = in1 << 16U; |
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| 88 | /* extract upper 16 bits to 32 bit result */ |
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| 89 | out2 = in1 & 0xFFFF0000; |
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| 90 | /* extract lower 16 bits to 32 bit result */ |
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| 91 | out3 = in2 << 16U; |
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| 92 | /* extract upper 16 bits to 32 bit result */ |
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| 93 | out4 = in2 & 0xFFFF0000; |
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| 94 | |||
| 95 | #else |
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| 96 | |||
| 97 | /* extract upper 16 bits to 32 bit result */ |
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| 98 | out1 = in1 & 0xFFFF0000; |
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| 99 | /* extract lower 16 bits to 32 bit result */ |
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| 100 | out2 = in1 << 16U; |
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| 101 | /* extract upper 16 bits to 32 bit result */ |
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| 102 | out3 = in2 & 0xFFFF0000; |
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| 103 | /* extract lower 16 bits to 32 bit result */ |
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| 104 | out4 = in2 << 16U; |
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| 105 | |||
| 106 | #endif // #ifndef ARM_MATH_BIG_ENDIAN |
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| 107 | |||
| 108 | *pDst++ = out1; |
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| 109 | *pDst++ = out2; |
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| 110 | *pDst++ = out3; |
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| 111 | *pDst++ = out4; |
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| 112 | |||
| 113 | /* Decrement the loop counter */ |
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| 114 | blkCnt--; |
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| 115 | } |
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| 116 | |||
| 117 | /* If the blockSize is not a multiple of 4, compute any remaining output samples here. |
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| 118 | ** No loop unrolling is used. */ |
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| 119 | blkCnt = blockSize % 0x4U; |
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| 120 | |||
| 121 | #else |
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| 122 | |||
| 123 | /* Run the below code for Cortex-M0 */ |
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| 124 | |||
| 125 | /* Loop over blockSize number of values */ |
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| 126 | blkCnt = blockSize; |
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| 127 | |||
| 128 | #endif /* #if defined (ARM_MATH_DSP) */ |
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| 129 | |||
| 130 | while (blkCnt > 0U) |
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| 131 | { |
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| 132 | /* C = (q31_t)A << 16 */ |
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| 133 | /* convert from q15 to q31 and then store the results in the destination buffer */ |
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| 134 | *pDst++ = (q31_t) * pIn++ << 16; |
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| 135 | |||
| 136 | /* Decrement the loop counter */ |
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| 137 | blkCnt--; |
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| 138 | } |
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| 139 | |||
| 140 | } |
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| 141 | |||
| 142 | /** |
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| 143 | * @} end of q15_to_x group |
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| 144 | */ |