MATHLIB_rsqrt_scalar.h

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#ifndef MATHLIB_RSQRT_SCALAR_H_
#define MATHLIB_RSQRT_SCALAR_H_ 1
 
#include <c6x_migration.h>
#include <float.h>
 
static inline float MATHLIB_rsqrt_scalar(float a);
 
#ifndef __cplusplus /* FOR PROTECTION PURPOSE - C++ NOT SUPPORTED. */
#pragma CODE_SECTION(MATHLIB_rsqrt_scalar, ".text:optci");
#endif
 
static inline float MATHLIB_rsqrt_scalar(float a)
{
   float Half  = 0.5f;
   float OneP5 = 1.5f;
   float Small = 1.17549435e-38f;
   float X0, X1, X2, X3;
 
   X0 = _rsqrsp(a);
   X1 = a * X0;
   X3 = OneP5 - (X1 * X0 * Half);
   X1 = X0 * X3;
   X2 = X1 * (OneP5 - (a * X1 * X1 * Half));
 
   if (a < Small) {
      X2 = _itof(0x7F800000u);
   }
 
   return (X2);
}
 
#endif /* MATHLIB_RSQRT_SCALAR_H_ */
 
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/*  End of file: MATHLIB_rsqrt_scalar.h                                      */
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