Diff: src/Cortex-M4-M3/BasicMathFunctions/arm_dot_prod_q7.c

Revision:

0:1014af42efd9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Cortex-M4-M3/BasicMathFunctions/arm_dot_prod_q7.c	Thu Mar 10 15:07:50 2011 +0000
@@ -0,0 +1,132 @@
+/* ----------------------------------------------------------------------  
+* Copyright (C) 2010 ARM Limited. All rights reserved.  
+*  
+* $Date:        29. November 2010  
+* $Revision: 	V1.0.3  
+*  
+* Project: 	    CMSIS DSP Library  
+* Title:		arm_dot_prod_q7.c  
+*  
+* Description:	Q7 dot product.  
+*  
+* Target Processor: Cortex-M4/Cortex-M3
+*  
+* Version 1.0.3 2010/11/29 
+*    Re-organized the CMSIS folders and updated documentation.  
+*   
+* Version 1.0.2 2010/11/11  
+*    Documentation updated.   
+*  
+* Version 1.0.1 2010/10/05   
+*    Production release and review comments incorporated.  
+*  
+* Version 1.0.0 2010/09/20   
+*    Production release and review comments incorporated.  
+*  
+* Version 0.0.7  2010/06/10   
+*    Misra-C changes done  
+* -------------------------------------------------------------------- */ 
+ 
+#include "arm_math.h" 
+ 
+/**  
+ * @ingroup groupMath  
+ */ 
+ 
+/**  
+ * @addtogroup dot_prod  
+ * @{  
+ */ 
+ 
+/**  
+ * @brief Dot product of Q7 vectors.  
+ * @param[in]       *pSrcA points to the first input vector  
+ * @param[in]       *pSrcB points to the second input vector  
+ * @param[in]       blockSize number of samples in each vector  
+ * @param[out]      *result output result returned here  
+ * @return none.  
+ *  
+ * <b>Scaling and Overflow Behavior:</b>  
+ * \par  
+ * The intermediate multiplications are in 1.7 x 1.7 = 2.14 format and these  
+ * results are added to an accumulator in 18.14 format.  
+ * Nonsaturating additions are used and there is no danger of wrap around as long as  
+ * the vectors are less than 2^18 elements long.  
+ * The return result is in 18.14 format.  
+ */ 
+ 
+void arm_dot_prod_q7( 
+  q7_t * pSrcA, 
+  q7_t * pSrcB, 
+  uint32_t blockSize, 
+  q31_t * result) 
+{ 
+  q31_t input1, input2;                          /* Temporary variables to store input */ 
+  q15_t in1, in2;                                /* Temporary variables to store input */ 
+  q31_t sum = 0;                                 /* Temporary variables to store output */ 
+  uint32_t blkCnt;                               /* loop counter */ 
+ 
+ 
+ 
+  /*loop Unrolling */ 
+  blkCnt = blockSize >> 2u; 
+ 
+  /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.  
+   ** a second loop below computes the remaining 1 to 3 samples. */ 
+  while(blkCnt > 0u) 
+  { 
+    /* Reading two inputs of SrcA buffer and packing */ 
+    in1 = (q15_t) * pSrcA++; 
+    in2 = (q15_t) * pSrcA++; 
+    input1 = ((q31_t) in1 & 0x0000FFFF) | ((q31_t) in2 << 16); 
+ 
+    /* Reading two inputs of SrcB buffer and packing */ 
+    in1 = (q15_t) * pSrcB++; 
+    in2 = (q15_t) * pSrcB++; 
+    input2 = ((q31_t) in1 & 0x0000FFFF) | ((q31_t) in2 << 16); 
+ 
+    /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */ 
+    /* Perform Dot product of 2 packed inputs using SMLALD and store the result in a temporary variable. */ 
+    sum = __SMLAD(input1, input2, sum); 
+ 
+    /* Reading two inputs of SrcA buffer and packing */ 
+    in1 = (q15_t) * pSrcA++; 
+    in2 = (q15_t) * pSrcA++; 
+    input1 = ((q31_t) in1 & 0x0000FFFF) | ((q31_t) in2 << 16); 
+ 
+    /* Reading two inputs of SrcB buffer and packing */ 
+    in1 = (q15_t) * pSrcB++; 
+    in2 = (q15_t) * pSrcB++; 
+    input2 = ((q31_t) in1 & 0x0000FFFF) | ((q31_t) in2 << 16); 
+ 
+    /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */ 
+    /* Perform Dot product of 2 packed inputs using SMLALD and store the result in a temporary variable. */ 
+    sum = __SMLAD(input1, input2, sum); 
+ 
+ 
+ 
+    /* Decrement the loop counter */ 
+    blkCnt--; 
+  } 
+ 
+  /* If the blockSize is not a multiple of 4, compute any remaining output samples here.  
+   ** No loop unrolling is used. */ 
+  blkCnt = blockSize % 0x4u; 
+ 
+  while(blkCnt > 0u) 
+  { 
+    /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */ 
+    /* Dot product and then store the results in a temporary buffer. */ 
+    sum = __SMLAD(*pSrcA++, *pSrcB++, sum); 
+ 
+    /* Decrement the loop counter */ 
+    blkCnt--; 
+  } 
+ 
+  /* Store the result in the destination buffer in 18.14 format */ 
+  *result = sum; 
+} 
+ 
+/**  
+ * @} end of dot_prod group  
+ */