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| <h1>arm_biquad_cascade_df1_fast_q15.c</h1> </div> |
| </div> |
| <div class="contents"> |
| <a href="arm__biquad__cascade__df1__fast__q15_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/* ---------------------------------------------------------------------- </span> |
| <a name="l00002"></a>00002 <span class="comment">* Copyright (C) 2010 ARM Limited. All rights reserved. </span> |
| <a name="l00003"></a>00003 <span class="comment">* </span> |
| <a name="l00004"></a>00004 <span class="comment">* $Date: 15. July 2011 </span> |
| <a name="l00005"></a>00005 <span class="comment">* $Revision: V1.0.10 </span> |
| <a name="l00006"></a>00006 <span class="comment">* </span> |
| <a name="l00007"></a>00007 <span class="comment">* Project: CMSIS DSP Library </span> |
| <a name="l00008"></a>00008 <span class="comment">* Title: arm_biquad_cascade_df1_fast_q15.c </span> |
| <a name="l00009"></a>00009 <span class="comment">* </span> |
| <a name="l00010"></a>00010 <span class="comment">* Description: Fast processing function for the </span> |
| <a name="l00011"></a>00011 <span class="comment">* Q15 Biquad cascade filter. </span> |
| <a name="l00012"></a>00012 <span class="comment">* </span> |
| <a name="l00013"></a>00013 <span class="comment">* Target Processor: Cortex-M4/Cortex-M3</span> |
| <a name="l00014"></a>00014 <span class="comment">* </span> |
| <a name="l00015"></a>00015 <span class="comment">* Version 1.0.10 2011/7/15 </span> |
| <a name="l00016"></a>00016 <span class="comment">* Big Endian support added and Merged M0 and M3/M4 Source code. </span> |
| <a name="l00017"></a>00017 <span class="comment">* </span> |
| <a name="l00018"></a>00018 <span class="comment">* Version 1.0.3 2010/11/29 </span> |
| <a name="l00019"></a>00019 <span class="comment">* Re-organized the CMSIS folders and updated documentation. </span> |
| <a name="l00020"></a>00020 <span class="comment">* </span> |
| <a name="l00021"></a>00021 <span class="comment">* Version 1.0.2 2010/11/11 </span> |
| <a name="l00022"></a>00022 <span class="comment">* Documentation updated. </span> |
| <a name="l00023"></a>00023 <span class="comment">* </span> |
| <a name="l00024"></a>00024 <span class="comment">* Version 1.0.1 2010/10/05 </span> |
| <a name="l00025"></a>00025 <span class="comment">* Production release and review comments incorporated. </span> |
| <a name="l00026"></a>00026 <span class="comment">* </span> |
| <a name="l00027"></a>00027 <span class="comment">* Version 1.0.0 2010/09/20 </span> |
| <a name="l00028"></a>00028 <span class="comment">* Production release and review comments incorporated. </span> |
| <a name="l00029"></a>00029 <span class="comment">* </span> |
| <a name="l00030"></a>00030 <span class="comment">* Version 0.0.9 2010/08/16 </span> |
| <a name="l00031"></a>00031 <span class="comment">* Initial version </span> |
| <a name="l00032"></a>00032 <span class="comment">* </span> |
| <a name="l00033"></a>00033 <span class="comment">* </span> |
| <a name="l00034"></a>00034 <span class="comment">* -------------------------------------------------------------------- */</span> |
| <a name="l00035"></a>00035 |
| <a name="l00036"></a>00036 <span class="preprocessor">#include "<a class="code" href="arm__math_8h.html">arm_math.h</a>"</span> |
| <a name="l00037"></a>00037 |
| <a name="l00069"></a><a class="code" href="group___biquad_cascade_d_f1.html#gaffb9792c0220882efd4c58f3c6a05fd7">00069</a> <span class="keywordtype">void</span> <a class="code" href="group___biquad_cascade_d_f1.html#gaffb9792c0220882efd4c58f3c6a05fd7" title="Fast but less precise processing function for the Q15 Biquad cascade filter for Cortex-M3 and Cortex-...">arm_biquad_cascade_df1_fast_q15</a>( |
| <a name="l00070"></a>00070 <span class="keyword">const</span> <a class="code" href="structarm__biquad__casd__df1__inst__q15.html" title="Instance structure for the Q15 Biquad cascade filter.">arm_biquad_casd_df1_inst_q15</a> * S, |
| <a name="l00071"></a>00071 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> * pSrc, |
| <a name="l00072"></a>00072 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> * pDst, |
| <a name="l00073"></a>00073 uint32_t <a class="code" href="arm__fir__example__f32_8c.html#ab6558f40a619c2502fbc24c880fd4fb0">blockSize</a>) |
| <a name="l00074"></a>00074 { |
| <a name="l00075"></a>00075 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pIn = pSrc; <span class="comment">/* Source pointer */</span> |
| <a name="l00076"></a>00076 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pOut = pDst; <span class="comment">/* Destination pointer */</span> |
| <a name="l00077"></a>00077 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> in; <span class="comment">/* Temporary variable to hold input value */</span> |
| <a name="l00078"></a>00078 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> out; <span class="comment">/* Temporary variable to hold output value */</span> |
| <a name="l00079"></a>00079 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> b0; <span class="comment">/* Temporary variable to hold bo value */</span> |
| <a name="l00080"></a>00080 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> b1, a1; <span class="comment">/* Filter coefficients */</span> |
| <a name="l00081"></a>00081 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> state_in, state_out; <span class="comment">/* Filter state variables */</span> |
| <a name="l00082"></a>00082 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> acc0; <span class="comment">/* Accumulator */</span> |
| <a name="l00083"></a>00083 int32_t shift = (int32_t) (15 - S-><a class="code" href="structarm__biquad__casd__df1__inst__q15.html#ada7e9d6269e6ed4eacf8f68729e9832d">postShift</a>); <span class="comment">/* Post shift */</span> |
| <a name="l00084"></a>00084 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pState = S-><a class="code" href="structarm__biquad__casd__df1__inst__q15.html#a5481104ef2f8f81360b80b47d69ae932">pState</a>; <span class="comment">/* State pointer */</span> |
| <a name="l00085"></a>00085 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pCoeffs = S-><a class="code" href="structarm__biquad__casd__df1__inst__q15.html#a1edaacdebb5b09d7635bf20c779855fc">pCoeffs</a>; <span class="comment">/* Coefficient pointer */</span> |
| <a name="l00086"></a>00086 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *pState_q31; <span class="comment">/* 32-bit state pointer for SIMD implementation */</span> |
| <a name="l00087"></a>00087 uint32_t sample, stage = S-><a class="code" href="structarm__biquad__casd__df1__inst__q15.html#ad6d95e70abcf4ff1300181415ad92153">numStages</a>; <span class="comment">/* Stage loop counter */</span> |
| <a name="l00088"></a>00088 |
| <a name="l00089"></a>00089 |
| <a name="l00090"></a>00090 |
| <a name="l00091"></a>00091 <span class="keywordflow">do</span> |
| <a name="l00092"></a>00092 { |
| <a name="l00093"></a>00093 <span class="comment">/* Initialize state pointer of type q31 */</span> |
| <a name="l00094"></a>00094 pState_q31 = (<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (pState); |
| <a name="l00095"></a>00095 |
| <a name="l00096"></a>00096 <span class="comment">/* Read the b0 and 0 coefficients using SIMD */</span> |
| <a name="l00097"></a>00097 b0 = *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pCoeffs)++; |
| <a name="l00098"></a>00098 |
| <a name="l00099"></a>00099 <span class="comment">/* Read the b1 and b2 coefficients using SIMD */</span> |
| <a name="l00100"></a>00100 b1 = *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pCoeffs)++; |
| <a name="l00101"></a>00101 |
| <a name="l00102"></a>00102 <span class="comment">/* Read the a1 and a2 coefficients using SIMD */</span> |
| <a name="l00103"></a>00103 a1 = *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pCoeffs)++; |
| <a name="l00104"></a>00104 |
| <a name="l00105"></a>00105 <span class="comment">/* Read the input state values from the state buffer: x[n-1], x[n-2] */</span> |
| <a name="l00106"></a>00106 state_in = (<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a>) (*pState_q31++); |
| <a name="l00107"></a>00107 |
| <a name="l00108"></a>00108 <span class="comment">/* Read the output state values from the state buffer: y[n-1], y[n-2] */</span> |
| <a name="l00109"></a>00109 state_out = (<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a>) (*pState_q31); |
| <a name="l00110"></a>00110 |
| <a name="l00111"></a>00111 <span class="comment">/* Apply loop unrolling and compute 2 output values simultaneously. */</span> |
| <a name="l00112"></a>00112 <span class="comment">/* The variables acc0 ... acc3 hold output values that are being computed: </span> |
| <a name="l00113"></a>00113 <span class="comment"> * </span> |
| <a name="l00114"></a>00114 <span class="comment"> * acc0 = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00115"></a>00115 <span class="comment"> * acc0 = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00116"></a>00116 <span class="comment"> */</span> |
| <a name="l00117"></a>00117 sample = blockSize >> 1u; |
| <a name="l00118"></a>00118 |
| <a name="l00119"></a>00119 <span class="comment">/* First part of the processing with loop unrolling. Compute 2 outputs at a time. </span> |
| <a name="l00120"></a>00120 <span class="comment"> ** a second loop below computes the remaining 1 sample. */</span> |
| <a name="l00121"></a>00121 <span class="keywordflow">while</span>(sample > 0u) |
| <a name="l00122"></a>00122 { |
| <a name="l00123"></a>00123 |
| <a name="l00124"></a>00124 <span class="comment">/* Read the input */</span> |
| <a name="l00125"></a>00125 in = *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pIn)++; |
| <a name="l00126"></a>00126 |
| <a name="l00127"></a>00127 <span class="comment">/* out = b0 * x[n] + 0 * 0 */</span> |
| <a name="l00128"></a>00128 out = __SMUAD(b0, in); |
| <a name="l00129"></a>00129 <span class="comment">/* acc0 = b1 * x[n-1] + acc0 += b2 * x[n-2] + out */</span> |
| <a name="l00130"></a>00130 acc0 = __SMLAD(b1, state_in, out); |
| <a name="l00131"></a>00131 <span class="comment">/* acc0 += a1 * y[n-1] + acc0 += a2 * y[n-2] */</span> |
| <a name="l00132"></a>00132 acc0 = __SMLAD(a1, state_out, acc0); |
| <a name="l00133"></a>00133 |
| <a name="l00134"></a>00134 <span class="comment">/* The result is converted from 3.29 to 1.31 and then saturation is applied */</span> |
| <a name="l00135"></a>00135 out = __SSAT((acc0 >> shift), 16); |
| <a name="l00136"></a>00136 |
| <a name="l00137"></a>00137 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00138"></a>00138 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00139"></a>00139 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00140"></a>00140 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00141"></a>00141 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00142"></a>00142 <span class="comment">/* Yn1 = acc0 */</span> |
| <a name="l00143"></a>00143 <span class="comment">/* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */</span> |
| <a name="l00144"></a>00144 <span class="comment">/* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */</span> |
| <a name="l00145"></a>00145 |
| <a name="l00146"></a>00146 <span class="preprocessor">#ifndef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00147"></a>00147 <span class="preprocessor"></span> |
| <a name="l00148"></a>00148 state_in = __PKHBT(in, state_in, 16); |
| <a name="l00149"></a>00149 state_out = __PKHBT(out, state_out, 16); |
| <a name="l00150"></a>00150 |
| <a name="l00151"></a>00151 <span class="preprocessor">#else</span> |
| <a name="l00152"></a>00152 <span class="preprocessor"></span> |
| <a name="l00153"></a>00153 state_in = __PKHBT(state_in >> 16, (in >> 16), 16); |
| <a name="l00154"></a>00154 state_out = __PKHBT(state_out >> 16, (out), 16); |
| <a name="l00155"></a>00155 |
| <a name="l00156"></a>00156 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00157"></a>00157 |
| <a name="l00158"></a>00158 <span class="comment">/* out = b0 * x[n] + 0 * 0 */</span> |
| <a name="l00159"></a>00159 out = __SMUADX(b0, in); |
| <a name="l00160"></a>00160 <span class="comment">/* acc0 = b1 * x[n-1] + acc0 += b2 * x[n-2] + out */</span> |
| <a name="l00161"></a>00161 acc0 = __SMLAD(b1, state_in, out); |
| <a name="l00162"></a>00162 <span class="comment">/* acc0 += a1 * y[n-1] + acc0 += a2 * y[n-2] */</span> |
| <a name="l00163"></a>00163 acc0 = __SMLAD(a1, state_out, acc0); |
| <a name="l00164"></a>00164 |
| <a name="l00165"></a>00165 <span class="comment">/* The result is converted from 3.29 to 1.31 and then saturation is applied */</span> |
| <a name="l00166"></a>00166 out = __SSAT((acc0 >> shift), 16); |
| <a name="l00167"></a>00167 |
| <a name="l00168"></a>00168 |
| <a name="l00169"></a>00169 <span class="comment">/* Store the output in the destination buffer. */</span> |
| <a name="l00170"></a>00170 |
| <a name="l00171"></a>00171 <span class="preprocessor">#ifndef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00172"></a>00172 <span class="preprocessor"></span> |
| <a name="l00173"></a>00173 *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pOut)++ = __PKHBT(state_out, out, 16); |
| <a name="l00174"></a>00174 |
| <a name="l00175"></a>00175 <span class="preprocessor">#else</span> |
| <a name="l00176"></a>00176 <span class="preprocessor"></span> |
| <a name="l00177"></a>00177 *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pOut)++ = __PKHBT(out, state_out >> 16, 16); |
| <a name="l00178"></a>00178 |
| <a name="l00179"></a>00179 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00180"></a>00180 |
| <a name="l00181"></a>00181 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00182"></a>00182 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00183"></a>00183 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00184"></a>00184 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00185"></a>00185 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00186"></a>00186 <span class="comment">/* Yn1 = acc0 */</span> |
| <a name="l00187"></a>00187 <span class="comment">/* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */</span> |
| <a name="l00188"></a>00188 <span class="comment">/* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */</span> |
| <a name="l00189"></a>00189 |
| <a name="l00190"></a>00190 <span class="preprocessor">#ifndef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00191"></a>00191 <span class="preprocessor"></span> |
| <a name="l00192"></a>00192 state_in = __PKHBT(in >> 16, state_in, 16); |
| <a name="l00193"></a>00193 state_out = __PKHBT(out, state_out, 16); |
| <a name="l00194"></a>00194 |
| <a name="l00195"></a>00195 <span class="preprocessor">#else</span> |
| <a name="l00196"></a>00196 <span class="preprocessor"></span> |
| <a name="l00197"></a>00197 state_in = __PKHBT(state_in >> 16, in, 16); |
| <a name="l00198"></a>00198 state_out = __PKHBT(state_out >> 16, out, 16); |
| <a name="l00199"></a>00199 |
| <a name="l00200"></a>00200 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00201"></a>00201 |
| <a name="l00202"></a>00202 |
| <a name="l00203"></a>00203 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00204"></a>00204 sample--; |
| <a name="l00205"></a>00205 |
| <a name="l00206"></a>00206 } |
| <a name="l00207"></a>00207 |
| <a name="l00208"></a>00208 <span class="comment">/* If the blockSize is not a multiple of 2, compute any remaining output samples here. </span> |
| <a name="l00209"></a>00209 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00210"></a>00210 |
| <a name="l00211"></a>00211 <span class="keywordflow">if</span>((blockSize & 0x1u) != 0u) |
| <a name="l00212"></a>00212 { |
| <a name="l00213"></a>00213 <span class="comment">/* Read the input */</span> |
| <a name="l00214"></a>00214 in = *pIn++; |
| <a name="l00215"></a>00215 |
| <a name="l00216"></a>00216 <span class="comment">/* out = b0 * x[n] + 0 * 0 */</span> |
| <a name="l00217"></a>00217 |
| <a name="l00218"></a>00218 <span class="preprocessor">#ifndef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00219"></a>00219 <span class="preprocessor"></span> |
| <a name="l00220"></a>00220 out = __SMUAD(b0, in); |
| <a name="l00221"></a>00221 |
| <a name="l00222"></a>00222 <span class="preprocessor">#else</span> |
| <a name="l00223"></a>00223 <span class="preprocessor"></span> |
| <a name="l00224"></a>00224 out = __SMUADX(b0, in); |
| <a name="l00225"></a>00225 |
| <a name="l00226"></a>00226 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00227"></a>00227 |
| <a name="l00228"></a>00228 <span class="comment">/* acc0 = b1 * x[n-1] + acc0 += b2 * x[n-2] + out */</span> |
| <a name="l00229"></a>00229 acc0 = __SMLAD(b1, state_in, out); |
| <a name="l00230"></a>00230 <span class="comment">/* acc0 += a1 * y[n-1] + acc0 += a2 * y[n-2] */</span> |
| <a name="l00231"></a>00231 acc0 = __SMLAD(a1, state_out, acc0); |
| <a name="l00232"></a>00232 |
| <a name="l00233"></a>00233 <span class="comment">/* The result is converted from 3.29 to 1.31 and then saturation is applied */</span> |
| <a name="l00234"></a>00234 out = __SSAT((acc0 >> shift), 16); |
| <a name="l00235"></a>00235 |
| <a name="l00236"></a>00236 <span class="comment">/* Store the output in the destination buffer. */</span> |
| <a name="l00237"></a>00237 *pOut++ = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) out; |
| <a name="l00238"></a>00238 |
| <a name="l00239"></a>00239 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00240"></a>00240 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00241"></a>00241 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00242"></a>00242 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00243"></a>00243 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00244"></a>00244 <span class="comment">/* Yn1 = acc0 */</span> |
| <a name="l00245"></a>00245 <span class="comment">/* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */</span> |
| <a name="l00246"></a>00246 <span class="comment">/* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */</span> |
| <a name="l00247"></a>00247 |
| <a name="l00248"></a>00248 <span class="preprocessor">#ifndef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00249"></a>00249 <span class="preprocessor"></span> |
| <a name="l00250"></a>00250 state_in = __PKHBT(in, state_in, 16); |
| <a name="l00251"></a>00251 state_out = __PKHBT(out, state_out, 16); |
| <a name="l00252"></a>00252 |
| <a name="l00253"></a>00253 <span class="preprocessor">#else</span> |
| <a name="l00254"></a>00254 <span class="preprocessor"></span> |
| <a name="l00255"></a>00255 state_in = __PKHBT(state_in >> 16, in, 16); |
| <a name="l00256"></a>00256 state_out = __PKHBT(state_out >> 16, out, 16); |
| <a name="l00257"></a>00257 |
| <a name="l00258"></a>00258 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00259"></a>00259 |
| <a name="l00260"></a>00260 } |
| <a name="l00261"></a>00261 |
| <a name="l00262"></a>00262 <span class="comment">/* The first stage goes from the input buffer to the output buffer. */</span> |
| <a name="l00263"></a>00263 <span class="comment">/* Subsequent (numStages - 1) occur in-place in the output buffer */</span> |
| <a name="l00264"></a>00264 pIn = pDst; |
| <a name="l00265"></a>00265 |
| <a name="l00266"></a>00266 <span class="comment">/* Reset the output pointer */</span> |
| <a name="l00267"></a>00267 pOut = pDst; |
| <a name="l00268"></a>00268 |
| <a name="l00269"></a>00269 <span class="comment">/* Store the updated state variables back into the state array */</span> |
| <a name="l00270"></a>00270 *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pState)++ = state_in; |
| <a name="l00271"></a>00271 *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(pState)++ = state_out; |
| <a name="l00272"></a>00272 |
| <a name="l00273"></a>00273 |
| <a name="l00274"></a>00274 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00275"></a>00275 stage--; |
| <a name="l00276"></a>00276 |
| <a name="l00277"></a>00277 } <span class="keywordflow">while</span>(stage > 0u); |
| <a name="l00278"></a>00278 } |
| <a name="l00279"></a>00279 |
| <a name="l00280"></a>00280 |
| </pre></div></div> |
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