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| <h1>arm_correlate_q15.c</h1> </div> |
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| <div class="contents"> |
| <a href="arm__correlate__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_correlate_q15.c </span> |
| <a name="l00009"></a>00009 <span class="comment">* </span> |
| <a name="l00010"></a>00010 <span class="comment">* Description: Correlation of Q15 sequences. </span> |
| <a name="l00011"></a>00011 <span class="comment">* </span> |
| <a name="l00012"></a>00012 <span class="comment">* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0</span> |
| <a name="l00013"></a>00013 <span class="comment">* </span> |
| <a name="l00014"></a>00014 <span class="comment">* Version 1.0.10 2011/7/15 </span> |
| <a name="l00015"></a>00015 <span class="comment">* Big Endian support added and Merged M0 and M3/M4 Source code. </span> |
| <a name="l00016"></a>00016 <span class="comment">* </span> |
| <a name="l00017"></a>00017 <span class="comment">* Version 1.0.3 2010/11/29 </span> |
| <a name="l00018"></a>00018 <span class="comment">* Re-organized the CMSIS folders and updated documentation. </span> |
| <a name="l00019"></a>00019 <span class="comment">* </span> |
| <a name="l00020"></a>00020 <span class="comment">* Version 1.0.2 2010/11/11 </span> |
| <a name="l00021"></a>00021 <span class="comment">* Documentation updated. </span> |
| <a name="l00022"></a>00022 <span class="comment">* </span> |
| <a name="l00023"></a>00023 <span class="comment">* Version 1.0.1 2010/10/05 </span> |
| <a name="l00024"></a>00024 <span class="comment">* Production release and review comments incorporated. </span> |
| <a name="l00025"></a>00025 <span class="comment">* </span> |
| <a name="l00026"></a>00026 <span class="comment">* Version 1.0.0 2010/09/20 </span> |
| <a name="l00027"></a>00027 <span class="comment">* Production release and review comments incorporated </span> |
| <a name="l00028"></a>00028 <span class="comment">* </span> |
| <a name="l00029"></a>00029 <span class="comment">* Version 0.0.7 2010/06/10 </span> |
| <a name="l00030"></a>00030 <span class="comment">* Misra-C changes done </span> |
| <a name="l00031"></a>00031 <span class="comment">* </span> |
| <a name="l00032"></a>00032 <span class="comment">* -------------------------------------------------------------------- */</span> |
| <a name="l00033"></a>00033 |
| <a name="l00034"></a>00034 <span class="preprocessor">#include "<a class="code" href="arm__math_8h.html">arm_math.h</a>"</span> |
| <a name="l00035"></a>00035 |
| <a name="l00068"></a><a class="code" href="group___corr.html#ga5ec96b8e420d68b0e626df0812274d46">00068</a> <span class="keywordtype">void</span> <a class="code" href="group___corr.html#ga5ec96b8e420d68b0e626df0812274d46" title="Correlation of Q15 sequences.">arm_correlate_q15</a>( |
| <a name="l00069"></a>00069 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> * pSrcA, |
| <a name="l00070"></a>00070 uint32_t <a class="code" href="arm__convolution__example__f32_8c.html#ace48ed566e2cd6a680f0681192e6af28">srcALen</a>, |
| <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> * pSrcB, |
| <a name="l00072"></a>00072 uint32_t <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>, |
| <a name="l00073"></a>00073 <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="l00074"></a>00074 { |
| <a name="l00075"></a>00075 |
| <a name="l00076"></a>00076 <span class="preprocessor">#ifndef ARM_MATH_CM0</span> |
| <a name="l00077"></a>00077 <span class="preprocessor"></span> |
| <a name="l00078"></a>00078 <span class="comment">/* Run the below code for Cortex-M4 and Cortex-M3 */</span> |
| <a name="l00079"></a>00079 |
| <a name="l00080"></a>00080 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pIn1; <span class="comment">/* inputA pointer */</span> |
| <a name="l00081"></a>00081 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pIn2; <span class="comment">/* inputB pointer */</span> |
| <a name="l00082"></a>00082 <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">/* output pointer */</span> |
| <a name="l00083"></a>00083 <a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a> sum, acc0, acc1, acc2, acc3; <span class="comment">/* Accumulators */</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> *px; <span class="comment">/* Intermediate inputA 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> *py; <span class="comment">/* Intermediate inputB pointer */</span> |
| <a name="l00086"></a>00086 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pSrc1; <span class="comment">/* Intermediate pointers */</span> |
| <a name="l00087"></a>00087 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> x0, x1, x2, x3, c0; <span class="comment">/* temporary variables for holding input and coefficient values */</span> |
| <a name="l00088"></a>00088 uint32_t j, k = 0u, count, blkCnt, outBlockSize, blockSize1, blockSize2, blockSize3; <span class="comment">/* loop counter */</span> |
| <a name="l00089"></a>00089 int32_t inc = 1; <span class="comment">/* Destination address modifier */</span> |
| <a name="l00090"></a>00090 <a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *pb; <span class="comment">/* 32 bit pointer for inputB buffer */</span> |
| <a name="l00091"></a>00091 |
| <a name="l00092"></a>00092 |
| <a name="l00093"></a>00093 <span class="comment">/* The algorithm implementation is based on the lengths of the inputs. */</span> |
| <a name="l00094"></a>00094 <span class="comment">/* srcB is always made to slide across srcA. */</span> |
| <a name="l00095"></a>00095 <span class="comment">/* So srcBLen is always considered as shorter or equal to srcALen */</span> |
| <a name="l00096"></a>00096 <span class="comment">/* But CORR(x, y) is reverse of CORR(y, x) */</span> |
| <a name="l00097"></a>00097 <span class="comment">/* So, when srcBLen > srcALen, output pointer is made to point to the end of the output buffer */</span> |
| <a name="l00098"></a>00098 <span class="comment">/* and the destination pointer modifier, inc is set to -1 */</span> |
| <a name="l00099"></a>00099 <span class="comment">/* If srcALen > srcBLen, zero pad has to be done to srcB to make the two inputs of same length */</span> |
| <a name="l00100"></a>00100 <span class="comment">/* But to improve the performance, </span> |
| <a name="l00101"></a>00101 <span class="comment"> * we include zeroes in the output instead of zero padding either of the the inputs*/</span> |
| <a name="l00102"></a>00102 <span class="comment">/* If srcALen > srcBLen, </span> |
| <a name="l00103"></a>00103 <span class="comment"> * (srcALen - srcBLen) zeroes has to included in the starting of the output buffer */</span> |
| <a name="l00104"></a>00104 <span class="comment">/* If srcALen < srcBLen, </span> |
| <a name="l00105"></a>00105 <span class="comment"> * (srcALen - srcBLen) zeroes has to included in the ending of the output buffer */</span> |
| <a name="l00106"></a>00106 <span class="keywordflow">if</span>(srcALen >= srcBLen) |
| <a name="l00107"></a>00107 { |
| <a name="l00108"></a>00108 <span class="comment">/* Initialization of inputA pointer */</span> |
| <a name="l00109"></a>00109 pIn1 = (pSrcA); |
| <a name="l00110"></a>00110 |
| <a name="l00111"></a>00111 <span class="comment">/* Initialization of inputB pointer */</span> |
| <a name="l00112"></a>00112 pIn2 = (pSrcB); |
| <a name="l00113"></a>00113 |
| <a name="l00114"></a>00114 <span class="comment">/* Number of output samples is calculated */</span> |
| <a name="l00115"></a>00115 outBlockSize = (2u * <a class="code" href="arm__convolution__example__f32_8c.html#ace48ed566e2cd6a680f0681192e6af28">srcALen</a>) - 1u; |
| <a name="l00116"></a>00116 |
| <a name="l00117"></a>00117 <span class="comment">/* When srcALen > srcBLen, zero padding is done to srcB </span> |
| <a name="l00118"></a>00118 <span class="comment"> * to make their lengths equal. </span> |
| <a name="l00119"></a>00119 <span class="comment"> * Instead, (outBlockSize - (srcALen + srcBLen - 1)) </span> |
| <a name="l00120"></a>00120 <span class="comment"> * number of output samples are made zero */</span> |
| <a name="l00121"></a>00121 j = outBlockSize - (srcALen + (srcBLen - 1u)); |
| <a name="l00122"></a>00122 |
| <a name="l00123"></a>00123 <span class="comment">/* Updating the pointer position to non zero value */</span> |
| <a name="l00124"></a>00124 pOut += j; |
| <a name="l00125"></a>00125 |
| <a name="l00126"></a>00126 } |
| <a name="l00127"></a>00127 <span class="keywordflow">else</span> |
| <a name="l00128"></a>00128 { |
| <a name="l00129"></a>00129 <span class="comment">/* Initialization of inputA pointer */</span> |
| <a name="l00130"></a>00130 pIn1 = (pSrcB); |
| <a name="l00131"></a>00131 |
| <a name="l00132"></a>00132 <span class="comment">/* Initialization of inputB pointer */</span> |
| <a name="l00133"></a>00133 pIn2 = (pSrcA); |
| <a name="l00134"></a>00134 |
| <a name="l00135"></a>00135 <span class="comment">/* srcBLen is always considered as shorter or equal to srcALen */</span> |
| <a name="l00136"></a>00136 j = <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>; |
| <a name="l00137"></a>00137 srcBLen = <a class="code" href="arm__convolution__example__f32_8c.html#ace48ed566e2cd6a680f0681192e6af28">srcALen</a>; |
| <a name="l00138"></a>00138 srcALen = j; |
| <a name="l00139"></a>00139 |
| <a name="l00140"></a>00140 <span class="comment">/* CORR(x, y) = Reverse order(CORR(y, x)) */</span> |
| <a name="l00141"></a>00141 <span class="comment">/* Hence set the destination pointer to point to the last output sample */</span> |
| <a name="l00142"></a>00142 pOut = pDst + ((srcALen + <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>) - 2u); |
| <a name="l00143"></a>00143 |
| <a name="l00144"></a>00144 <span class="comment">/* Destination address modifier is set to -1 */</span> |
| <a name="l00145"></a>00145 inc = -1; |
| <a name="l00146"></a>00146 |
| <a name="l00147"></a>00147 } |
| <a name="l00148"></a>00148 |
| <a name="l00149"></a>00149 <span class="comment">/* The function is internally </span> |
| <a name="l00150"></a>00150 <span class="comment"> * divided into three parts according to the number of multiplications that has to be </span> |
| <a name="l00151"></a>00151 <span class="comment"> * taken place between inputA samples and inputB samples. In the first part of the </span> |
| <a name="l00152"></a>00152 <span class="comment"> * algorithm, the multiplications increase by one for every iteration. </span> |
| <a name="l00153"></a>00153 <span class="comment"> * In the second part of the algorithm, srcBLen number of multiplications are done. </span> |
| <a name="l00154"></a>00154 <span class="comment"> * In the third part of the algorithm, the multiplications decrease by one </span> |
| <a name="l00155"></a>00155 <span class="comment"> * for every iteration.*/</span> |
| <a name="l00156"></a>00156 <span class="comment">/* The algorithm is implemented in three stages. </span> |
| <a name="l00157"></a>00157 <span class="comment"> * The loop counters of each stage is initiated here. */</span> |
| <a name="l00158"></a>00158 blockSize1 = srcBLen - 1u; |
| <a name="l00159"></a>00159 blockSize2 = srcALen - (srcBLen - 1u); |
| <a name="l00160"></a>00160 blockSize3 = blockSize1; |
| <a name="l00161"></a>00161 |
| <a name="l00162"></a>00162 <span class="comment">/* -------------------------- </span> |
| <a name="l00163"></a>00163 <span class="comment"> * Initializations of stage1 </span> |
| <a name="l00164"></a>00164 <span class="comment"> * -------------------------*/</span> |
| <a name="l00165"></a>00165 |
| <a name="l00166"></a>00166 <span class="comment">/* sum = x[0] * y[srcBlen - 1] </span> |
| <a name="l00167"></a>00167 <span class="comment"> * sum = x[0] * y[srcBlen - 2] + x[1] * y[srcBlen - 1] </span> |
| <a name="l00168"></a>00168 <span class="comment"> * .... </span> |
| <a name="l00169"></a>00169 <span class="comment"> * sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen - 1] * y[srcBLen - 1] </span> |
| <a name="l00170"></a>00170 <span class="comment"> */</span> |
| <a name="l00171"></a>00171 |
| <a name="l00172"></a>00172 <span class="comment">/* In this stage the MAC operations are increased by 1 for every iteration. </span> |
| <a name="l00173"></a>00173 <span class="comment"> The count variable holds the number of MAC operations performed */</span> |
| <a name="l00174"></a>00174 count = 1u; |
| <a name="l00175"></a>00175 |
| <a name="l00176"></a>00176 <span class="comment">/* Working pointer of inputA */</span> |
| <a name="l00177"></a>00177 px = pIn1; |
| <a name="l00178"></a>00178 |
| <a name="l00179"></a>00179 <span class="comment">/* Working pointer of inputB */</span> |
| <a name="l00180"></a>00180 pSrc1 = pIn2 + (srcBLen - 1u); |
| <a name="l00181"></a>00181 py = pSrc1; |
| <a name="l00182"></a>00182 |
| <a name="l00183"></a>00183 <span class="comment">/* ------------------------ </span> |
| <a name="l00184"></a>00184 <span class="comment"> * Stage1 process </span> |
| <a name="l00185"></a>00185 <span class="comment"> * ----------------------*/</span> |
| <a name="l00186"></a>00186 |
| <a name="l00187"></a>00187 <span class="comment">/* The first loop starts here */</span> |
| <a name="l00188"></a>00188 <span class="keywordflow">while</span>(blockSize1 > 0u) |
| <a name="l00189"></a>00189 { |
| <a name="l00190"></a>00190 <span class="comment">/* Accumulator is made zero for every iteration */</span> |
| <a name="l00191"></a>00191 sum = 0; |
| <a name="l00192"></a>00192 |
| <a name="l00193"></a>00193 <span class="comment">/* Apply loop unrolling and compute 4 MACs simultaneously. */</span> |
| <a name="l00194"></a>00194 k = count >> 2; |
| <a name="l00195"></a>00195 |
| <a name="l00196"></a>00196 <span class="comment">/* First part of the processing with loop unrolling. Compute 4 MACs at a time. </span> |
| <a name="l00197"></a>00197 <span class="comment"> ** a second loop below computes MACs for the remaining 1 to 3 samples. */</span> |
| <a name="l00198"></a>00198 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00199"></a>00199 { |
| <a name="l00200"></a>00200 <span class="comment">/* x[0] * y[srcBLen - 4] , x[1] * y[srcBLen - 3] */</span> |
| <a name="l00201"></a>00201 sum = __SMLALD(*<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(px)++, *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(py)++, sum); |
| <a name="l00202"></a>00202 <span class="comment">/* x[3] * y[srcBLen - 1] , x[2] * y[srcBLen - 2] */</span> |
| <a name="l00203"></a>00203 sum = __SMLALD(*<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(px)++, *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(py)++, sum); |
| <a name="l00204"></a>00204 |
| <a name="l00205"></a>00205 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00206"></a>00206 k--; |
| <a name="l00207"></a>00207 } |
| <a name="l00208"></a>00208 |
| <a name="l00209"></a>00209 <span class="comment">/* If the count is not a multiple of 4, compute any remaining MACs here. </span> |
| <a name="l00210"></a>00210 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00211"></a>00211 k = count % 0x4u; |
| <a name="l00212"></a>00212 |
| <a name="l00213"></a>00213 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00214"></a>00214 { |
| <a name="l00215"></a>00215 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00216"></a>00216 <span class="comment">/* x[0] * y[srcBLen - 1] */</span> |
| <a name="l00217"></a>00217 sum = __SMLALD(*px++, *py++, sum); |
| <a name="l00218"></a>00218 |
| <a name="l00219"></a>00219 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00220"></a>00220 k--; |
| <a name="l00221"></a>00221 } |
| <a name="l00222"></a>00222 |
| <a name="l00223"></a>00223 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00224"></a>00224 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT((sum >> 15), 16)); |
| <a name="l00225"></a>00225 <span class="comment">/* Destination pointer is updated according to the address modifier, inc */</span> |
| <a name="l00226"></a>00226 pOut += inc; |
| <a name="l00227"></a>00227 |
| <a name="l00228"></a>00228 <span class="comment">/* Update the inputA and inputB pointers for next MAC calculation */</span> |
| <a name="l00229"></a>00229 py = pSrc1 - count; |
| <a name="l00230"></a>00230 px = pIn1; |
| <a name="l00231"></a>00231 |
| <a name="l00232"></a>00232 <span class="comment">/* Increment the MAC count */</span> |
| <a name="l00233"></a>00233 count++; |
| <a name="l00234"></a>00234 |
| <a name="l00235"></a>00235 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00236"></a>00236 blockSize1--; |
| <a name="l00237"></a>00237 } |
| <a name="l00238"></a>00238 |
| <a name="l00239"></a>00239 <span class="comment">/* -------------------------- </span> |
| <a name="l00240"></a>00240 <span class="comment"> * Initializations of stage2 </span> |
| <a name="l00241"></a>00241 <span class="comment"> * ------------------------*/</span> |
| <a name="l00242"></a>00242 |
| <a name="l00243"></a>00243 <span class="comment">/* sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen-1] * y[srcBLen-1] </span> |
| <a name="l00244"></a>00244 <span class="comment"> * sum = x[1] * y[0] + x[2] * y[1] +...+ x[srcBLen] * y[srcBLen-1] </span> |
| <a name="l00245"></a>00245 <span class="comment"> * .... </span> |
| <a name="l00246"></a>00246 <span class="comment"> * sum = x[srcALen-srcBLen-2] * y[0] + x[srcALen-srcBLen-1] * y[1] +...+ x[srcALen-1] * y[srcBLen-1] </span> |
| <a name="l00247"></a>00247 <span class="comment"> */</span> |
| <a name="l00248"></a>00248 |
| <a name="l00249"></a>00249 <span class="comment">/* Working pointer of inputA */</span> |
| <a name="l00250"></a>00250 px = pIn1; |
| <a name="l00251"></a>00251 |
| <a name="l00252"></a>00252 <span class="comment">/* Working pointer of inputB */</span> |
| <a name="l00253"></a>00253 py = pIn2; |
| <a name="l00254"></a>00254 |
| <a name="l00255"></a>00255 <span class="comment">/* Initialize inputB pointer of type q31 */</span> |
| <a name="l00256"></a>00256 pb = (<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (py); |
| <a name="l00257"></a>00257 |
| <a name="l00258"></a>00258 <span class="comment">/* count is index by which the pointer pIn1 to be incremented */</span> |
| <a name="l00259"></a>00259 count = 0u; |
| <a name="l00260"></a>00260 |
| <a name="l00261"></a>00261 <span class="comment">/* ------------------- </span> |
| <a name="l00262"></a>00262 <span class="comment"> * Stage2 process </span> |
| <a name="l00263"></a>00263 <span class="comment"> * ------------------*/</span> |
| <a name="l00264"></a>00264 |
| <a name="l00265"></a>00265 <span class="comment">/* Stage2 depends on srcBLen as in this stage srcBLen number of MACS are performed. </span> |
| <a name="l00266"></a>00266 <span class="comment"> * So, to loop unroll over blockSize2, </span> |
| <a name="l00267"></a>00267 <span class="comment"> * srcBLen should be greater than or equal to 4, to loop unroll the srcBLen loop */</span> |
| <a name="l00268"></a>00268 <span class="keywordflow">if</span>(srcBLen >= 4u) |
| <a name="l00269"></a>00269 { |
| <a name="l00270"></a>00270 <span class="comment">/* Loop unroll over blockSize2, by 4 */</span> |
| <a name="l00271"></a>00271 blkCnt = blockSize2 >> 2u; |
| <a name="l00272"></a>00272 |
| <a name="l00273"></a>00273 <span class="keywordflow">while</span>(blkCnt > 0u) |
| <a name="l00274"></a>00274 { |
| <a name="l00275"></a>00275 <span class="comment">/* Set all accumulators to zero */</span> |
| <a name="l00276"></a>00276 acc0 = 0; |
| <a name="l00277"></a>00277 acc1 = 0; |
| <a name="l00278"></a>00278 acc2 = 0; |
| <a name="l00279"></a>00279 acc3 = 0; |
| <a name="l00280"></a>00280 |
| <a name="l00281"></a>00281 <span class="comment">/* read x[0], x[1] samples */</span> |
| <a name="l00282"></a>00282 x0 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (px++); |
| <a name="l00283"></a>00283 <span class="comment">/* read x[1], x[2] samples */</span> |
| <a name="l00284"></a>00284 x1 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (px++); |
| <a name="l00285"></a>00285 |
| <a name="l00286"></a>00286 <span class="comment">/* Apply loop unrolling and compute 4 MACs simultaneously. */</span> |
| <a name="l00287"></a>00287 k = srcBLen >> 2u; |
| <a name="l00288"></a>00288 |
| <a name="l00289"></a>00289 <span class="comment">/* First part of the processing with loop unrolling. Compute 4 MACs at a time. </span> |
| <a name="l00290"></a>00290 <span class="comment"> ** a second loop below computes MACs for the remaining 1 to 3 samples. */</span> |
| <a name="l00291"></a>00291 <span class="keywordflow">do</span> |
| <a name="l00292"></a>00292 { |
| <a name="l00293"></a>00293 <span class="comment">/* Read the first two inputB samples using SIMD: </span> |
| <a name="l00294"></a>00294 <span class="comment"> * y[0] and y[1] */</span> |
| <a name="l00295"></a>00295 c0 = *(pb++); |
| <a name="l00296"></a>00296 |
| <a name="l00297"></a>00297 <span class="comment">/* acc0 += x[0] * y[0] + x[1] * y[1] */</span> |
| <a name="l00298"></a>00298 acc0 = __SMLALD(x0, c0, acc0); |
| <a name="l00299"></a>00299 |
| <a name="l00300"></a>00300 <span class="comment">/* acc1 += x[1] * y[0] + x[2] * y[1] */</span> |
| <a name="l00301"></a>00301 acc1 = __SMLALD(x1, c0, acc1); |
| <a name="l00302"></a>00302 |
| <a name="l00303"></a>00303 <span class="comment">/* Read x[2], x[3] */</span> |
| <a name="l00304"></a>00304 x2 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (px++); |
| <a name="l00305"></a>00305 |
| <a name="l00306"></a>00306 <span class="comment">/* Read x[3], x[4] */</span> |
| <a name="l00307"></a>00307 x3 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (px++); |
| <a name="l00308"></a>00308 |
| <a name="l00309"></a>00309 <span class="comment">/* acc2 += x[2] * y[0] + x[3] * y[1] */</span> |
| <a name="l00310"></a>00310 acc2 = __SMLALD(x2, c0, acc2); |
| <a name="l00311"></a>00311 |
| <a name="l00312"></a>00312 <span class="comment">/* acc3 += x[3] * y[0] + x[4] * y[1] */</span> |
| <a name="l00313"></a>00313 acc3 = __SMLALD(x3, c0, acc3); |
| <a name="l00314"></a>00314 |
| <a name="l00315"></a>00315 <span class="comment">/* Read y[2] and y[3] */</span> |
| <a name="l00316"></a>00316 c0 = *(pb++); |
| <a name="l00317"></a>00317 |
| <a name="l00318"></a>00318 <span class="comment">/* acc0 += x[2] * y[2] + x[3] * y[3] */</span> |
| <a name="l00319"></a>00319 acc0 = __SMLALD(x2, c0, acc0); |
| <a name="l00320"></a>00320 |
| <a name="l00321"></a>00321 <span class="comment">/* acc1 += x[3] * y[2] + x[4] * y[3] */</span> |
| <a name="l00322"></a>00322 acc1 = __SMLALD(x3, c0, acc1); |
| <a name="l00323"></a>00323 |
| <a name="l00324"></a>00324 <span class="comment">/* Read x[4], x[5] */</span> |
| <a name="l00325"></a>00325 x0 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (px++); |
| <a name="l00326"></a>00326 |
| <a name="l00327"></a>00327 <span class="comment">/* Read x[5], x[6] */</span> |
| <a name="l00328"></a>00328 x1 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (px++); |
| <a name="l00329"></a>00329 |
| <a name="l00330"></a>00330 <span class="comment">/* acc2 += x[4] * y[2] + x[5] * y[3] */</span> |
| <a name="l00331"></a>00331 acc2 = __SMLALD(x0, c0, acc2); |
| <a name="l00332"></a>00332 |
| <a name="l00333"></a>00333 <span class="comment">/* acc3 += x[5] * y[2] + x[6] * y[3] */</span> |
| <a name="l00334"></a>00334 acc3 = __SMLALD(x1, c0, acc3); |
| <a name="l00335"></a>00335 |
| <a name="l00336"></a>00336 } <span class="keywordflow">while</span>(--k); |
| <a name="l00337"></a>00337 |
| <a name="l00338"></a>00338 <span class="comment">/* For the next MAC operations, SIMD is not used </span> |
| <a name="l00339"></a>00339 <span class="comment"> * So, the 16 bit pointer if inputB, py is updated */</span> |
| <a name="l00340"></a>00340 py = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *) (pb); |
| <a name="l00341"></a>00341 |
| <a name="l00342"></a>00342 <span class="comment">/* If the srcBLen is not a multiple of 4, compute any remaining MACs here. </span> |
| <a name="l00343"></a>00343 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00344"></a>00344 k = srcBLen % 0x4u; |
| <a name="l00345"></a>00345 |
| <a name="l00346"></a>00346 <span class="keywordflow">if</span>(k == 1u) |
| <a name="l00347"></a>00347 { |
| <a name="l00348"></a>00348 <span class="comment">/* Read y[4] */</span> |
| <a name="l00349"></a>00349 c0 = *py; |
| <a name="l00350"></a>00350 <span class="preprocessor">#ifdef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00351"></a>00351 <span class="preprocessor"></span> |
| <a name="l00352"></a>00352 c0 = c0 << 16u; |
| <a name="l00353"></a>00353 |
| <a name="l00354"></a>00354 <span class="preprocessor">#else</span> |
| <a name="l00355"></a>00355 <span class="preprocessor"></span> |
| <a name="l00356"></a>00356 c0 = c0 & 0x0000FFFF; |
| <a name="l00357"></a>00357 |
| <a name="l00358"></a>00358 <span class="preprocessor">#endif </span><span class="comment">/* #ifdef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00359"></a>00359 <span class="comment">/* Read x[7] */</span> |
| <a name="l00360"></a>00360 x3 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) px++; |
| <a name="l00361"></a>00361 |
| <a name="l00362"></a>00362 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00363"></a>00363 acc0 = __SMLALD(x0, c0, acc0); |
| <a name="l00364"></a>00364 acc1 = __SMLALD(x1, c0, acc1); |
| <a name="l00365"></a>00365 acc2 = __SMLALDX(x1, c0, acc2); |
| <a name="l00366"></a>00366 acc3 = __SMLALDX(x3, c0, acc3); |
| <a name="l00367"></a>00367 } |
| <a name="l00368"></a>00368 |
| <a name="l00369"></a>00369 <span class="keywordflow">if</span>(k == 2u) |
| <a name="l00370"></a>00370 { |
| <a name="l00371"></a>00371 <span class="comment">/* Read y[4], y[5] */</span> |
| <a name="l00372"></a>00372 c0 = *(pb); |
| <a name="l00373"></a>00373 |
| <a name="l00374"></a>00374 <span class="comment">/* Read x[7], x[8] */</span> |
| <a name="l00375"></a>00375 x3 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) px++; |
| <a name="l00376"></a>00376 |
| <a name="l00377"></a>00377 <span class="comment">/* Read x[9] */</span> |
| <a name="l00378"></a>00378 x2 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) px++; |
| <a name="l00379"></a>00379 |
| <a name="l00380"></a>00380 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00381"></a>00381 acc0 = __SMLALD(x0, c0, acc0); |
| <a name="l00382"></a>00382 acc1 = __SMLALD(x1, c0, acc1); |
| <a name="l00383"></a>00383 acc2 = __SMLALD(x3, c0, acc2); |
| <a name="l00384"></a>00384 acc3 = __SMLALD(x2, c0, acc3); |
| <a name="l00385"></a>00385 } |
| <a name="l00386"></a>00386 |
| <a name="l00387"></a>00387 <span class="keywordflow">if</span>(k == 3u) |
| <a name="l00388"></a>00388 { |
| <a name="l00389"></a>00389 <span class="comment">/* Read y[4], y[5] */</span> |
| <a name="l00390"></a>00390 c0 = *pb++; |
| <a name="l00391"></a>00391 |
| <a name="l00392"></a>00392 <span class="comment">/* Read x[7], x[8] */</span> |
| <a name="l00393"></a>00393 x3 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) px++; |
| <a name="l00394"></a>00394 |
| <a name="l00395"></a>00395 <span class="comment">/* Read x[9] */</span> |
| <a name="l00396"></a>00396 x2 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) px++; |
| <a name="l00397"></a>00397 |
| <a name="l00398"></a>00398 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00399"></a>00399 acc0 = __SMLALD(x0, c0, acc0); |
| <a name="l00400"></a>00400 acc1 = __SMLALD(x1, c0, acc1); |
| <a name="l00401"></a>00401 acc2 = __SMLALD(x3, c0, acc2); |
| <a name="l00402"></a>00402 acc3 = __SMLALD(x2, c0, acc3); |
| <a name="l00403"></a>00403 |
| <a name="l00404"></a>00404 <span class="comment">/* Read y[6] */</span> |
| <a name="l00405"></a>00405 <span class="preprocessor">#ifdef ARM_MATH_BIG_ENDIAN</span> |
| <a name="l00406"></a>00406 <span class="preprocessor"></span> |
| <a name="l00407"></a>00407 c0 = (*pb); |
| <a name="l00408"></a>00408 c0 = c0 & 0xFFFF0000; |
| <a name="l00409"></a>00409 |
| <a name="l00410"></a>00410 <span class="preprocessor">#else</span> |
| <a name="l00411"></a>00411 <span class="preprocessor"></span> |
| <a name="l00412"></a>00412 c0 = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (*pb); |
| <a name="l00413"></a>00413 c0 = c0 & 0x0000FFFF; |
| <a name="l00414"></a>00414 |
| <a name="l00415"></a>00415 <span class="preprocessor">#endif </span><span class="comment">/* #ifdef ARM_MATH_BIG_ENDIAN */</span> |
| <a name="l00416"></a>00416 <span class="comment">/* Read x[10] */</span> |
| <a name="l00417"></a>00417 x3 = *(<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) px++; |
| <a name="l00418"></a>00418 |
| <a name="l00419"></a>00419 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00420"></a>00420 acc0 = __SMLALDX(x1, c0, acc0); |
| <a name="l00421"></a>00421 acc1 = __SMLALD(x2, c0, acc1); |
| <a name="l00422"></a>00422 acc2 = __SMLALDX(x2, c0, acc2); |
| <a name="l00423"></a>00423 acc3 = __SMLALDX(x3, c0, acc3); |
| <a name="l00424"></a>00424 } |
| <a name="l00425"></a>00425 |
| <a name="l00426"></a>00426 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00427"></a>00427 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT(acc0 >> 15, 16)); |
| <a name="l00428"></a>00428 <span class="comment">/* Destination pointer is updated according to the address modifier, inc */</span> |
| <a name="l00429"></a>00429 pOut += inc; |
| <a name="l00430"></a>00430 |
| <a name="l00431"></a>00431 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT(acc1 >> 15, 16)); |
| <a name="l00432"></a>00432 pOut += inc; |
| <a name="l00433"></a>00433 |
| <a name="l00434"></a>00434 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT(acc2 >> 15, 16)); |
| <a name="l00435"></a>00435 pOut += inc; |
| <a name="l00436"></a>00436 |
| <a name="l00437"></a>00437 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT(acc3 >> 15, 16)); |
| <a name="l00438"></a>00438 pOut += inc; |
| <a name="l00439"></a>00439 |
| <a name="l00440"></a>00440 <span class="comment">/* Increment the count by 4 as 4 output values are computed */</span> |
| <a name="l00441"></a>00441 count += 4u; |
| <a name="l00442"></a>00442 |
| <a name="l00443"></a>00443 <span class="comment">/* Update the inputA and inputB pointers for next MAC calculation */</span> |
| <a name="l00444"></a>00444 px = pIn1 + count; |
| <a name="l00445"></a>00445 py = pIn2; |
| <a name="l00446"></a>00446 pb = (<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a> *) (py); |
| <a name="l00447"></a>00447 |
| <a name="l00448"></a>00448 |
| <a name="l00449"></a>00449 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00450"></a>00450 blkCnt--; |
| <a name="l00451"></a>00451 } |
| <a name="l00452"></a>00452 |
| <a name="l00453"></a>00453 <span class="comment">/* If the blockSize2 is not a multiple of 4, compute any remaining output samples here. </span> |
| <a name="l00454"></a>00454 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00455"></a>00455 blkCnt = blockSize2 % 0x4u; |
| <a name="l00456"></a>00456 |
| <a name="l00457"></a>00457 <span class="keywordflow">while</span>(blkCnt > 0u) |
| <a name="l00458"></a>00458 { |
| <a name="l00459"></a>00459 <span class="comment">/* Accumulator is made zero for every iteration */</span> |
| <a name="l00460"></a>00460 sum = 0; |
| <a name="l00461"></a>00461 |
| <a name="l00462"></a>00462 <span class="comment">/* Apply loop unrolling and compute 4 MACs simultaneously. */</span> |
| <a name="l00463"></a>00463 k = srcBLen >> 2u; |
| <a name="l00464"></a>00464 |
| <a name="l00465"></a>00465 <span class="comment">/* First part of the processing with loop unrolling. Compute 4 MACs at a time. </span> |
| <a name="l00466"></a>00466 <span class="comment"> ** a second loop below computes MACs for the remaining 1 to 3 samples. */</span> |
| <a name="l00467"></a>00467 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00468"></a>00468 { |
| <a name="l00469"></a>00469 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00470"></a>00470 sum += ((<a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a>) * px++ * *py++); |
| <a name="l00471"></a>00471 sum += ((<a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a>) * px++ * *py++); |
| <a name="l00472"></a>00472 sum += ((<a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a>) * px++ * *py++); |
| <a name="l00473"></a>00473 sum += ((<a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a>) * px++ * *py++); |
| <a name="l00474"></a>00474 |
| <a name="l00475"></a>00475 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00476"></a>00476 k--; |
| <a name="l00477"></a>00477 } |
| <a name="l00478"></a>00478 |
| <a name="l00479"></a>00479 <span class="comment">/* If the srcBLen is not a multiple of 4, compute any remaining MACs here. </span> |
| <a name="l00480"></a>00480 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00481"></a>00481 k = srcBLen % 0x4u; |
| <a name="l00482"></a>00482 |
| <a name="l00483"></a>00483 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00484"></a>00484 { |
| <a name="l00485"></a>00485 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00486"></a>00486 sum += ((<a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a>) * px++ * *py++); |
| <a name="l00487"></a>00487 |
| <a name="l00488"></a>00488 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00489"></a>00489 k--; |
| <a name="l00490"></a>00490 } |
| <a name="l00491"></a>00491 |
| <a name="l00492"></a>00492 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00493"></a>00493 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT(sum >> 15, 16)); |
| <a name="l00494"></a>00494 <span class="comment">/* Destination pointer is updated according to the address modifier, inc */</span> |
| <a name="l00495"></a>00495 pOut += inc; |
| <a name="l00496"></a>00496 |
| <a name="l00497"></a>00497 <span class="comment">/* Increment count by 1, as one output value is computed */</span> |
| <a name="l00498"></a>00498 count++; |
| <a name="l00499"></a>00499 |
| <a name="l00500"></a>00500 <span class="comment">/* Update the inputA and inputB pointers for next MAC calculation */</span> |
| <a name="l00501"></a>00501 px = pIn1 + count; |
| <a name="l00502"></a>00502 py = pIn2; |
| <a name="l00503"></a>00503 |
| <a name="l00504"></a>00504 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00505"></a>00505 blkCnt--; |
| <a name="l00506"></a>00506 } |
| <a name="l00507"></a>00507 } |
| <a name="l00508"></a>00508 <span class="keywordflow">else</span> |
| <a name="l00509"></a>00509 { |
| <a name="l00510"></a>00510 <span class="comment">/* If the srcBLen is not a multiple of 4, </span> |
| <a name="l00511"></a>00511 <span class="comment"> * the blockSize2 loop cannot be unrolled by 4 */</span> |
| <a name="l00512"></a>00512 blkCnt = blockSize2; |
| <a name="l00513"></a>00513 |
| <a name="l00514"></a>00514 <span class="keywordflow">while</span>(blkCnt > 0u) |
| <a name="l00515"></a>00515 { |
| <a name="l00516"></a>00516 <span class="comment">/* Accumulator is made zero for every iteration */</span> |
| <a name="l00517"></a>00517 sum = 0; |
| <a name="l00518"></a>00518 |
| <a name="l00519"></a>00519 <span class="comment">/* Loop over srcBLen */</span> |
| <a name="l00520"></a>00520 k = <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>; |
| <a name="l00521"></a>00521 |
| <a name="l00522"></a>00522 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00523"></a>00523 { |
| <a name="l00524"></a>00524 <span class="comment">/* Perform the multiply-accumulate */</span> |
| <a name="l00525"></a>00525 sum += ((<a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a>) * px++ * *py++); |
| <a name="l00526"></a>00526 |
| <a name="l00527"></a>00527 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00528"></a>00528 k--; |
| <a name="l00529"></a>00529 } |
| <a name="l00530"></a>00530 |
| <a name="l00531"></a>00531 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00532"></a>00532 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT(sum >> 15, 16)); |
| <a name="l00533"></a>00533 <span class="comment">/* Destination pointer is updated according to the address modifier, inc */</span> |
| <a name="l00534"></a>00534 pOut += inc; |
| <a name="l00535"></a>00535 |
| <a name="l00536"></a>00536 <span class="comment">/* Increment the MAC count */</span> |
| <a name="l00537"></a>00537 count++; |
| <a name="l00538"></a>00538 |
| <a name="l00539"></a>00539 <span class="comment">/* Update the inputA and inputB pointers for next MAC calculation */</span> |
| <a name="l00540"></a>00540 px = pIn1 + count; |
| <a name="l00541"></a>00541 py = pIn2; |
| <a name="l00542"></a>00542 |
| <a name="l00543"></a>00543 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00544"></a>00544 blkCnt--; |
| <a name="l00545"></a>00545 } |
| <a name="l00546"></a>00546 } |
| <a name="l00547"></a>00547 |
| <a name="l00548"></a>00548 <span class="comment">/* -------------------------- </span> |
| <a name="l00549"></a>00549 <span class="comment"> * Initializations of stage3 </span> |
| <a name="l00550"></a>00550 <span class="comment"> * -------------------------*/</span> |
| <a name="l00551"></a>00551 |
| <a name="l00552"></a>00552 <span class="comment">/* sum += x[srcALen-srcBLen+1] * y[0] + x[srcALen-srcBLen+2] * y[1] +...+ x[srcALen-1] * y[srcBLen-1] </span> |
| <a name="l00553"></a>00553 <span class="comment"> * sum += x[srcALen-srcBLen+2] * y[0] + x[srcALen-srcBLen+3] * y[1] +...+ x[srcALen-1] * y[srcBLen-1] </span> |
| <a name="l00554"></a>00554 <span class="comment"> * .... </span> |
| <a name="l00555"></a>00555 <span class="comment"> * sum += x[srcALen-2] * y[0] + x[srcALen-1] * y[1] </span> |
| <a name="l00556"></a>00556 <span class="comment"> * sum += x[srcALen-1] * y[0] </span> |
| <a name="l00557"></a>00557 <span class="comment"> */</span> |
| <a name="l00558"></a>00558 |
| <a name="l00559"></a>00559 <span class="comment">/* In this stage the MAC operations are decreased by 1 for every iteration. </span> |
| <a name="l00560"></a>00560 <span class="comment"> The count variable holds the number of MAC operations performed */</span> |
| <a name="l00561"></a>00561 count = srcBLen - 1u; |
| <a name="l00562"></a>00562 |
| <a name="l00563"></a>00563 <span class="comment">/* Working pointer of inputA */</span> |
| <a name="l00564"></a>00564 pSrc1 = (pIn1 + <a class="code" href="arm__convolution__example__f32_8c.html#ace48ed566e2cd6a680f0681192e6af28">srcALen</a>) - (srcBLen - 1u); |
| <a name="l00565"></a>00565 px = pSrc1; |
| <a name="l00566"></a>00566 |
| <a name="l00567"></a>00567 <span class="comment">/* Working pointer of inputB */</span> |
| <a name="l00568"></a>00568 py = pIn2; |
| <a name="l00569"></a>00569 |
| <a name="l00570"></a>00570 <span class="comment">/* ------------------- </span> |
| <a name="l00571"></a>00571 <span class="comment"> * Stage3 process </span> |
| <a name="l00572"></a>00572 <span class="comment"> * ------------------*/</span> |
| <a name="l00573"></a>00573 |
| <a name="l00574"></a>00574 <span class="keywordflow">while</span>(blockSize3 > 0u) |
| <a name="l00575"></a>00575 { |
| <a name="l00576"></a>00576 <span class="comment">/* Accumulator is made zero for every iteration */</span> |
| <a name="l00577"></a>00577 sum = 0; |
| <a name="l00578"></a>00578 |
| <a name="l00579"></a>00579 <span class="comment">/* Apply loop unrolling and compute 4 MACs simultaneously. */</span> |
| <a name="l00580"></a>00580 k = count >> 2u; |
| <a name="l00581"></a>00581 |
| <a name="l00582"></a>00582 <span class="comment">/* First part of the processing with loop unrolling. Compute 4 MACs at a time. </span> |
| <a name="l00583"></a>00583 <span class="comment"> ** a second loop below computes MACs for the remaining 1 to 3 samples. */</span> |
| <a name="l00584"></a>00584 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00585"></a>00585 { |
| <a name="l00586"></a>00586 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00587"></a>00587 <span class="comment">/* sum += x[srcALen - srcBLen + 4] * y[3] , sum += x[srcALen - srcBLen + 3] * y[2] */</span> |
| <a name="l00588"></a>00588 sum = __SMLALD(*<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(px)++, *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(py)++, sum); |
| <a name="l00589"></a>00589 <span class="comment">/* sum += x[srcALen - srcBLen + 2] * y[1] , sum += x[srcALen - srcBLen + 1] * y[0] */</span> |
| <a name="l00590"></a>00590 sum = __SMLALD(*<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(px)++, *<a class="code" href="arm__math_8h.html#a9de2e0a5785be82866bcb96012282248" title="definition to read/write two 16 bit values.">__SIMD32</a>(py)++, sum); |
| <a name="l00591"></a>00591 |
| <a name="l00592"></a>00592 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00593"></a>00593 k--; |
| <a name="l00594"></a>00594 } |
| <a name="l00595"></a>00595 |
| <a name="l00596"></a>00596 <span class="comment">/* If the count is not a multiple of 4, compute any remaining MACs here. </span> |
| <a name="l00597"></a>00597 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00598"></a>00598 k = count % 0x4u; |
| <a name="l00599"></a>00599 |
| <a name="l00600"></a>00600 <span class="keywordflow">while</span>(k > 0u) |
| <a name="l00601"></a>00601 { |
| <a name="l00602"></a>00602 <span class="comment">/* Perform the multiply-accumulates */</span> |
| <a name="l00603"></a>00603 sum = __SMLALD(*px++, *py++, sum); |
| <a name="l00604"></a>00604 |
| <a name="l00605"></a>00605 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00606"></a>00606 k--; |
| <a name="l00607"></a>00607 } |
| <a name="l00608"></a>00608 |
| <a name="l00609"></a>00609 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00610"></a>00610 *pOut = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) (__SSAT((sum >> 15), 16)); |
| <a name="l00611"></a>00611 <span class="comment">/* Destination pointer is updated according to the address modifier, inc */</span> |
| <a name="l00612"></a>00612 pOut += inc; |
| <a name="l00613"></a>00613 |
| <a name="l00614"></a>00614 <span class="comment">/* Update the inputA and inputB pointers for next MAC calculation */</span> |
| <a name="l00615"></a>00615 px = ++pSrc1; |
| <a name="l00616"></a>00616 py = pIn2; |
| <a name="l00617"></a>00617 |
| <a name="l00618"></a>00618 <span class="comment">/* Decrement the MAC count */</span> |
| <a name="l00619"></a>00619 count--; |
| <a name="l00620"></a>00620 |
| <a name="l00621"></a>00621 <span class="comment">/* Decrement the loop counter */</span> |
| <a name="l00622"></a>00622 blockSize3--; |
| <a name="l00623"></a>00623 } |
| <a name="l00624"></a>00624 |
| <a name="l00625"></a>00625 <span class="preprocessor">#else</span> |
| <a name="l00626"></a>00626 <span class="preprocessor"></span> |
| <a name="l00627"></a>00627 <span class="comment">/* Run the below code for Cortex-M0 */</span> |
| <a name="l00628"></a>00628 |
| <a name="l00629"></a>00629 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pIn1 = pSrcA; <span class="comment">/* inputA pointer */</span> |
| <a name="l00630"></a>00630 <a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a> *pIn2 = pSrcB + (srcBLen - 1u); <span class="comment">/* inputB pointer */</span> |
| <a name="l00631"></a>00631 <a class="code" href="arm__math_8h.html#a5aea1cb12fc02d9d44c8abf217eaa5c6" title="64-bit fractional data type in 1.63 format.">q63_t</a> sum; <span class="comment">/* Accumulators */</span> |
| <a name="l00632"></a>00632 uint32_t i = 0u, j; <span class="comment">/* loop counters */</span> |
| <a name="l00633"></a>00633 uint32_t inv = 0u; <span class="comment">/* Reverse order flag */</span> |
| <a name="l00634"></a>00634 uint32_t tot = 0u; <span class="comment">/* Length */</span> |
| <a name="l00635"></a>00635 |
| <a name="l00636"></a>00636 <span class="comment">/* The algorithm implementation is based on the lengths of the inputs. */</span> |
| <a name="l00637"></a>00637 <span class="comment">/* srcB is always made to slide across srcA. */</span> |
| <a name="l00638"></a>00638 <span class="comment">/* So srcBLen is always considered as shorter or equal to srcALen */</span> |
| <a name="l00639"></a>00639 <span class="comment">/* But CORR(x, y) is reverse of CORR(y, x) */</span> |
| <a name="l00640"></a>00640 <span class="comment">/* So, when srcBLen > srcALen, output pointer is made to point to the end of the output buffer */</span> |
| <a name="l00641"></a>00641 <span class="comment">/* and a varaible, inv is set to 1 */</span> |
| <a name="l00642"></a>00642 <span class="comment">/* If lengths are not equal then zero pad has to be done to make the two </span> |
| <a name="l00643"></a>00643 <span class="comment"> * inputs of same length. But to improve the performance, we include zeroes </span> |
| <a name="l00644"></a>00644 <span class="comment"> * in the output instead of zero padding either of the the inputs*/</span> |
| <a name="l00645"></a>00645 <span class="comment">/* If srcALen > srcBLen, (srcALen - srcBLen) zeroes has to included in the </span> |
| <a name="l00646"></a>00646 <span class="comment"> * starting of the output buffer */</span> |
| <a name="l00647"></a>00647 <span class="comment">/* If srcALen < srcBLen, (srcALen - srcBLen) zeroes has to included in the </span> |
| <a name="l00648"></a>00648 <span class="comment"> * ending of the output buffer */</span> |
| <a name="l00649"></a>00649 <span class="comment">/* Once the zero padding is done the remaining of the output is calcualted </span> |
| <a name="l00650"></a>00650 <span class="comment"> * using convolution but with the shorter signal time shifted. */</span> |
| <a name="l00651"></a>00651 |
| <a name="l00652"></a>00652 <span class="comment">/* Calculate the length of the remaining sequence */</span> |
| <a name="l00653"></a>00653 tot = ((srcALen + <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>) - 2u); |
| <a name="l00654"></a>00654 |
| <a name="l00655"></a>00655 <span class="keywordflow">if</span>(srcALen > srcBLen) |
| <a name="l00656"></a>00656 { |
| <a name="l00657"></a>00657 <span class="comment">/* Calculating the number of zeros to be padded to the output */</span> |
| <a name="l00658"></a>00658 j = srcALen - <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>; |
| <a name="l00659"></a>00659 |
| <a name="l00660"></a>00660 <span class="comment">/* Initialise the pointer after zero padding */</span> |
| <a name="l00661"></a>00661 pDst += j; |
| <a name="l00662"></a>00662 } |
| <a name="l00663"></a>00663 |
| <a name="l00664"></a>00664 <span class="keywordflow">else</span> <span class="keywordflow">if</span>(srcALen < srcBLen) |
| <a name="l00665"></a>00665 { |
| <a name="l00666"></a>00666 <span class="comment">/* Initialization to inputB pointer */</span> |
| <a name="l00667"></a>00667 pIn1 = pSrcB; |
| <a name="l00668"></a>00668 |
| <a name="l00669"></a>00669 <span class="comment">/* Initialization to the end of inputA pointer */</span> |
| <a name="l00670"></a>00670 pIn2 = pSrcA + (srcALen - 1u); |
| <a name="l00671"></a>00671 |
| <a name="l00672"></a>00672 <span class="comment">/* Initialisation of the pointer after zero padding */</span> |
| <a name="l00673"></a>00673 pDst = pDst + tot; |
| <a name="l00674"></a>00674 |
| <a name="l00675"></a>00675 <span class="comment">/* Swapping the lengths */</span> |
| <a name="l00676"></a>00676 j = <a class="code" href="arm__convolution__example__f32_8c.html#ace48ed566e2cd6a680f0681192e6af28">srcALen</a>; |
| <a name="l00677"></a>00677 srcALen = <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>; |
| <a name="l00678"></a>00678 srcBLen = j; |
| <a name="l00679"></a>00679 |
| <a name="l00680"></a>00680 <span class="comment">/* Setting the reverse flag */</span> |
| <a name="l00681"></a>00681 inv = 1; |
| <a name="l00682"></a>00682 |
| <a name="l00683"></a>00683 } |
| <a name="l00684"></a>00684 |
| <a name="l00685"></a>00685 <span class="comment">/* Loop to calculate convolution for output length number of times */</span> |
| <a name="l00686"></a>00686 <span class="keywordflow">for</span> (i = 0u; i <= tot; i++) |
| <a name="l00687"></a>00687 { |
| <a name="l00688"></a>00688 <span class="comment">/* Initialize sum with zero to carry on MAC operations */</span> |
| <a name="l00689"></a>00689 sum = 0; |
| <a name="l00690"></a>00690 |
| <a name="l00691"></a>00691 <span class="comment">/* Loop to perform MAC operations according to convolution equation */</span> |
| <a name="l00692"></a>00692 <span class="keywordflow">for</span> (j = 0u; j <= i; j++) |
| <a name="l00693"></a>00693 { |
| <a name="l00694"></a>00694 <span class="comment">/* Check the array limitations */</span> |
| <a name="l00695"></a>00695 <span class="keywordflow">if</span>((((i - j) < <a class="code" href="arm__convolution__example__f32_8c.html#aea71286f498978c5ed3775609b974fc8">srcBLen</a>) && (j < srcALen))) |
| <a name="l00696"></a>00696 { |
| <a name="l00697"></a>00697 <span class="comment">/* z[i] += x[i-j] * y[j] */</span> |
| <a name="l00698"></a>00698 sum += ((<a class="code" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0" title="32-bit fractional data type in 1.31 format.">q31_t</a>) pIn1[j] * pIn2[-((int32_t) i - j)]); |
| <a name="l00699"></a>00699 } |
| <a name="l00700"></a>00700 } |
| <a name="l00701"></a>00701 <span class="comment">/* Store the output in the destination buffer */</span> |
| <a name="l00702"></a>00702 <span class="keywordflow">if</span>(inv == 1) |
| <a name="l00703"></a>00703 *pDst-- = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) __SSAT((sum >> 15u), 16u); |
| <a name="l00704"></a>00704 <span class="keywordflow">else</span> |
| <a name="l00705"></a>00705 *pDst++ = (<a class="code" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea" title="16-bit fractional data type in 1.15 format.">q15_t</a>) __SSAT((sum >> 15u), 16u); |
| <a name="l00706"></a>00706 } |
| <a name="l00707"></a>00707 |
| <a name="l00708"></a>00708 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_CM0 */</span> |
| <a name="l00709"></a>00709 |
| <a name="l00710"></a>00710 } |
| <a name="l00711"></a>00711 |
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