Import of the watch repository from Pebble

third_party/ARM/Source/ComplexMathFunctions/arm_cmplx_mag_f32.c

@@ -0,0 +1,165 @@
+/* ----------------------------------------------------------------------    
+* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
+*    
+* $Date:        19. March 2015
+* $Revision: 	V.1.4.5
+*    
+* Project: 	    CMSIS DSP Library    
+* Title:		arm_cmplx_mag_f32.c    
+*    
+* Description:	Floating-point complex magnitude.    
+*    
+* 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"
+
+/**    
+ * @ingroup groupCmplxMath    
+ */
+
+/**    
+ * @defgroup cmplx_mag Complex Magnitude    
+ *    
+ * Computes the magnitude of the elements of a complex data vector.    
+ *   
+ * The <code>pSrc</code> points to the source data and    
+ * <code>pDst</code> points to the where the result should be written.    
+ * <code>numSamples</code> specifies the number of complex samples    
+ * in the input array and the data is stored in an interleaved fashion    
+ * (real, imag, real, imag, ...).    
+ * The input array has a total of <code>2*numSamples</code> values;    
+ * the output array has a total of <code>numSamples</code> values.    
+ * The underlying algorithm is used:    
+ *    
+ * <pre>    
+ * for(n=0; n<numSamples; n++) {    
+ *     pDst[n] = sqrt(pSrc[(2*n)+0]^2 + pSrc[(2*n)+1]^2);    
+ * }    
+ * </pre>    
+ *    
+ * There are separate functions for floating-point, Q15, and Q31 data types.    
+ */
+
+/**    
+ * @addtogroup cmplx_mag    
+ * @{    
+ */
+/**    
+ * @brief Floating-point complex magnitude.    
+ * @param[in]       *pSrc points to complex input buffer    
+ * @param[out]      *pDst points to real output buffer    
+ * @param[in]       numSamples number of complex samples in the input vector    
+ * @return none.    
+ *    
+ */
+
+
+void arm_cmplx_mag_f32(
+  float32_t * pSrc,
+  float32_t * pDst,
+  uint32_t numSamples)
+{
+  float32_t realIn, imagIn;                      /* Temporary variables to hold input values */
+
+#ifndef ARM_MATH_CM0_FAMILY
+
+  /* Run the below code for Cortex-M4 and Cortex-M3 */
+  uint32_t blkCnt;                               /* loop counter */
+
+  /*loop Unrolling */
+  blkCnt = numSamples >> 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)
+  {
+
+    /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
+    realIn = *pSrc++;
+    imagIn = *pSrc++;
+    /* store the result in the destination buffer. */
+    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
+
+    realIn = *pSrc++;
+    imagIn = *pSrc++;
+    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
+
+    realIn = *pSrc++;
+    imagIn = *pSrc++;
+    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
+
+    realIn = *pSrc++;
+    imagIn = *pSrc++;
+    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
+
+
+    /* Decrement the loop counter */
+    blkCnt--;
+  }
+
+  /* If the numSamples is not a multiple of 4, compute any remaining output samples here.    
+   ** No loop unrolling is used. */
+  blkCnt = numSamples % 0x4u;
+
+  while(blkCnt > 0u)
+  {
+    /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
+    realIn = *pSrc++;
+    imagIn = *pSrc++;
+    /* store the result in the destination buffer. */
+    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
+
+    /* Decrement the loop counter */
+    blkCnt--;
+  }
+
+#else
+
+  /* Run the below code for Cortex-M0 */
+
+  while(numSamples > 0u)
+  {
+    /* out = sqrt((real * real) + (imag * imag)) */
+    realIn = *pSrc++;
+    imagIn = *pSrc++;
+    /* store the result in the destination buffer. */
+    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
+
+    /* Decrement the loop counter */
+    numSamples--;
+  }
+
+#endif /* #ifndef ARM_MATH_CM0_FAMILY */
+
+}
+
+/**    
+ * @} end of cmplx_mag group    
+ */