arm_add_q31.c 2.6 KB

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  1. /* ----------------------------------------------------------------------
  2. * Project: CMSIS DSP Library
  3. * Title: arm_add_q31.c
  4. * Description: Q31 vector addition
  5. *
  6. * $Date: 18. March 2019
  7. * $Revision: V1.6.0
  8. *
  9. * Target Processor: Cortex-M cores
  10. * -------------------------------------------------------------------- */
  11. /*
  12. * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
  13. *
  14. * SPDX-License-Identifier: Apache-2.0
  15. *
  16. * Licensed under the Apache License, Version 2.0 (the License); you may
  17. * not use this file except in compliance with the License.
  18. * You may obtain a copy of the License at
  19. *
  20. * www.apache.org/licenses/LICENSE-2.0
  21. *
  22. * Unless required by applicable law or agreed to in writing, software
  23. * distributed under the License is distributed on an AS IS BASIS, WITHOUT
  24. * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  25. * See the License for the specific language governing permissions and
  26. * limitations under the License.
  27. */
  28. #include "arm_math.h"
  29. /**
  30. @ingroup groupMath
  31. */
  32. /**
  33. @addtogroup BasicAdd
  34. @{
  35. */
  36. /**
  37. @brief Q31 vector addition.
  38. @param[in] pSrcA points to the first input vector
  39. @param[in] pSrcB points to the second input vector
  40. @param[out] pDst points to the output vector
  41. @param[in] blockSize number of samples in each vector
  42. @return none
  43. @par Scaling and Overflow Behavior
  44. The function uses saturating arithmetic.
  45. Results outside of the allowable Q31 range [0x80000000 0x7FFFFFFF] are saturated.
  46. */
  47. void arm_add_q31(
  48. const q31_t * pSrcA,
  49. const q31_t * pSrcB,
  50. q31_t * pDst,
  51. uint32_t blockSize)
  52. {
  53. uint32_t blkCnt; /* Loop counter */
  54. #if defined (ARM_MATH_LOOPUNROLL)
  55. /* Loop unrolling: Compute 4 outputs at a time */
  56. blkCnt = blockSize >> 2U;
  57. while (blkCnt > 0U)
  58. {
  59. /* C = A + B */
  60. /* Add and store result in destination buffer. */
  61. *pDst++ = __QADD(*pSrcA++, *pSrcB++);
  62. *pDst++ = __QADD(*pSrcA++, *pSrcB++);
  63. *pDst++ = __QADD(*pSrcA++, *pSrcB++);
  64. *pDst++ = __QADD(*pSrcA++, *pSrcB++);
  65. /* Decrement loop counter */
  66. blkCnt--;
  67. }
  68. /* Loop unrolling: Compute remaining outputs */
  69. blkCnt = blockSize % 0x4U;
  70. #else
  71. /* Initialize blkCnt with number of samples */
  72. blkCnt = blockSize;
  73. #endif /* #if defined (ARM_MATH_LOOPUNROLL) */
  74. while (blkCnt > 0U)
  75. {
  76. /* C = A + B */
  77. /* Add and store result in destination buffer. */
  78. *pDst++ = __QADD(*pSrcA++, *pSrcB++);
  79. /* Decrement loop counter */
  80. blkCnt--;
  81. }
  82. }
  83. /**
  84. @} end of BasicAdd group
  85. */