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diff --git a/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q15.c b/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q15.c
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+++ b/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q15.c
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+/* ----------------------------------------------------------------------
+* Copyright (C) 2010-2014 ARM Limited. All rights reserved.
+*
+* $Date: 31. July 2014
+* $Revision: V1.4.4
+*
+* Project: CMSIS DSP Library
+* Title: arm_cfft_radix2_q15.c
+*
+* Description: Radix-2 Decimation in Frequency CFFT & CIFFT Fixed point processing function
+*
+*
+* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions
+* are met:
+* - Redistributions of source code must retain the above copyright
+* notice, this list of conditions and the following disclaimer.
+* - Redistributions in binary form must reproduce the above copyright
+* notice, this list of conditions and the following disclaimer in
+* the documentation and/or other materials provided with the
+* distribution.
+* - Neither the name of ARM LIMITED nor the names of its contributors
+* may be used to endorse or promote products derived from this
+* software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+* POSSIBILITY OF SUCH DAMAGE.
+* -------------------------------------------------------------------- */
+
+#include "arm_math.h"
+
+void arm_radix2_butterfly_q15(
+ q15_t * pSrc,
+ uint32_t fftLen,
+ q15_t * pCoef,
+ uint16_t twidCoefModifier);
+
+void arm_radix2_butterfly_inverse_q15(
+ q15_t * pSrc,
+ uint32_t fftLen,
+ q15_t * pCoef,
+ uint16_t twidCoefModifier);
+
+void arm_bitreversal_q15(
+ q15_t * pSrc,
+ uint32_t fftLen,
+ uint16_t bitRevFactor,
+ uint16_t * pBitRevTab);
+
+/**
+ * @ingroup groupTransforms
+ */
+
+/**
+ * @addtogroup ComplexFFT
+ * @{
+ */
+
+/**
+ * @details
+ * @brief Processing function for the fixed-point CFFT/CIFFT.
+ * @deprecated Do not use this function. It has been superseded by \ref arm_cfft_q15 and will be removed
+ * @param[in] *S points to an instance of the fixed-point CFFT/CIFFT structure.
+ * @param[in, out] *pSrc points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place.
+ * @return none.
+ */
+
+void arm_cfft_radix2_q15(
+ const arm_cfft_radix2_instance_q15 * S,
+ q15_t * pSrc)
+{
+
+ if(S->ifftFlag == 1u)
+ {
+ arm_radix2_butterfly_inverse_q15(pSrc, S->fftLen,
+ S->pTwiddle, S->twidCoefModifier);
+ }
+ else
+ {
+ arm_radix2_butterfly_q15(pSrc, S->fftLen,
+ S->pTwiddle, S->twidCoefModifier);
+ }
+
+ arm_bitreversal_q15(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable);
+}
+
+/**
+ * @} end of ComplexFFT group
+ */
+
+void arm_radix2_butterfly_q15(
+ q15_t * pSrc,
+ uint32_t fftLen,
+ q15_t * pCoef,
+ uint16_t twidCoefModifier)
+{
+#ifndef ARM_MATH_CM0_FAMILY
+
+ unsigned i, j, k, l;
+ unsigned n1, n2, ia;
+ q15_t in;
+ q31_t T, S, R;
+ q31_t coeff, out1, out2;
+
+ //N = fftLen;
+ n2 = fftLen;
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (i = 0; i < n2; i++)
+ {
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+ in = ((int16_t) (T & 0xFFFF)) >> 1;
+ T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+ in = ((int16_t) (S & 0xFFFF)) >> 1;
+ S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUAD(coeff, R) >> 16;
+ out2 = __SMUSDX(coeff, R);
+
+#else
+
+ out1 = __SMUSDX(R, coeff) >> 16u;
+ out2 = __SMUAD(coeff, R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ i++;
+ l++;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+ in = ((int16_t) (T & 0xFFFF)) >> 1;
+ T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+ in = ((int16_t) (S & 0xFFFF)) >> 1;
+ S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUAD(coeff, R) >> 16;
+ out2 = __SMUSDX(coeff, R);
+
+#else
+
+ out1 = __SMUSDX(R, coeff) >> 16u;
+ out2 = __SMUAD(coeff, R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUAD(coeff, R) >> 16;
+ out2 = __SMUSDX(coeff, R);
+
+#else
+
+ out1 = __SMUSDX(R, coeff) >> 16u;
+ out2 = __SMUAD(coeff, R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ i += n1;
+
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUAD(coeff, R) >> 16;
+ out2 = __SMUSDX(coeff, R);
+
+#else
+
+ out1 = __SMUSDX(R, coeff) >> 16u;
+ out2 = __SMUAD(coeff, R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = 0; i < fftLen; i += n1)
+ {
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) = R;
+
+ i += n1;
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) = R;
+
+ } // groups loop end
+
+
+#else
+
+ unsigned i, j, k, l;
+ unsigned n1, n2, ia;
+ q15_t xt, yt, cosVal, sinVal;
+
+
+ //N = fftLen;
+ n2 = fftLen;
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = (pSrc[2 * i] >> 1u) - (pSrc[2 * l] >> 1u);
+ pSrc[2 * i] = ((pSrc[2 * i] >> 1u) + (pSrc[2 * l] >> 1u)) >> 1u;
+
+ yt = (pSrc[2 * i + 1] >> 1u) - (pSrc[2 * l + 1] >> 1u);
+ pSrc[2 * i + 1] =
+ ((pSrc[2 * l + 1] >> 1u) + (pSrc[2 * i + 1] >> 1u)) >> 1u;
+
+ pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) +
+ ((int16_t) (((q31_t) yt * sinVal) >> 16)));
+
+ pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) -
+ ((int16_t) (((q31_t) xt * sinVal) >> 16)));
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
+
+ pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) +
+ ((int16_t) (((q31_t) yt * sinVal) >> 16)));
+
+ pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) -
+ ((int16_t) (((q31_t) xt * sinVal) >> 16)));
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+#endif // #ifndef ARM_MATH_CM0_FAMILY
+
+}
+
+
+void arm_radix2_butterfly_inverse_q15(
+ q15_t * pSrc,
+ uint32_t fftLen,
+ q15_t * pCoef,
+ uint16_t twidCoefModifier)
+{
+#ifndef ARM_MATH_CM0_FAMILY
+
+ unsigned i, j, k, l;
+ unsigned n1, n2, ia;
+ q15_t in;
+ q31_t T, S, R;
+ q31_t coeff, out1, out2;
+
+ //N = fftLen;
+ n2 = fftLen;
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (i = 0; i < n2; i++)
+ {
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+ in = ((int16_t) (T & 0xFFFF)) >> 1;
+ T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+ in = ((int16_t) (S & 0xFFFF)) >> 1;
+ S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUSD(coeff, R) >> 16;
+ out2 = __SMUADX(coeff, R);
+#else
+
+ out1 = __SMUADX(R, coeff) >> 16u;
+ out2 = __SMUSD(__QSUB(0, coeff), R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ i++;
+ l++;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+ in = ((int16_t) (T & 0xFFFF)) >> 1;
+ T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+ in = ((int16_t) (S & 0xFFFF)) >> 1;
+ S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUSD(coeff, R) >> 16;
+ out2 = __SMUADX(coeff, R);
+#else
+
+ out1 = __SMUADX(R, coeff) >> 16u;
+ out2 = __SMUSD(__QSUB(0, coeff), R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUSD(coeff, R) >> 16;
+ out2 = __SMUADX(coeff, R);
+
+#else
+
+ out1 = __SMUADX(R, coeff) >> 16u;
+ out2 = __SMUSD(__QSUB(0, coeff), R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ i += n1;
+
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
+
+#ifndef ARM_MATH_BIG_ENDIAN
+
+ out1 = __SMUSD(coeff, R) >> 16;
+ out2 = __SMUADX(coeff, R);
+#else
+
+ out1 = __SMUADX(R, coeff) >> 16u;
+ out2 = __SMUSD(__QSUB(0, coeff), R);
+
+#endif // #ifndef ARM_MATH_BIG_ENDIAN
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) =
+ (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+
+ T = _SIMD32_OFFSET(pSrc + (2 * i));
+
+ S = _SIMD32_OFFSET(pSrc + (2 * l));
+
+ R = __QSUB16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
+
+ _SIMD32_OFFSET(pSrc + (2u * l)) = R;
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+#else
+
+
+ unsigned i, j, k, l;
+ unsigned n1, n2, ia;
+ q15_t xt, yt, cosVal, sinVal;
+
+ //N = fftLen;
+ n2 = fftLen;
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = (pSrc[2 * i] >> 1u) - (pSrc[2 * l] >> 1u);
+ pSrc[2 * i] = ((pSrc[2 * i] >> 1u) + (pSrc[2 * l] >> 1u)) >> 1u;
+
+ yt = (pSrc[2 * i + 1] >> 1u) - (pSrc[2 * l + 1] >> 1u);
+ pSrc[2 * i + 1] =
+ ((pSrc[2 * l + 1] >> 1u) + (pSrc[2 * i + 1] >> 1u)) >> 1u;
+
+ pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) -
+ ((int16_t) (((q31_t) yt * sinVal) >> 16)));
+
+ pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) +
+ ((int16_t) (((q31_t) xt * sinVal) >> 16)));
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
+
+ pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) -
+ ((int16_t) (((q31_t) yt * sinVal) >> 16)));
+
+ pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) +
+ ((int16_t) (((q31_t) xt * sinVal) >> 16)));
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = 0; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
+
+ } // groups loop end
+
+
+#endif // #ifndef ARM_MATH_CM0_FAMILY
+
+}
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