Performs multiplication of an integer with a multiplier which is less than one, using quantized integer arithmetic which is consistent with AndroidNN's CPU executor. More...

#include <ConvImpl.hpp>

Public Member Functions
	QuantizedMultiplierSmallerThanOne (float multiplier)
	Constructs a QuantizedMultiplierSmallerThanOne which will multiply by the given multiplier. More...

int32_t	operator* (int32_t rhs) const
	The implementation of this function is adapted from Android NN's MultiplyByQuantizedMultiplierSmallerThanOne(). More...

Detailed Description

Performs multiplication of an integer with a multiplier which is less than one, using quantized integer arithmetic which is consistent with AndroidNN's CPU executor.

Definition at line 26 of file ConvImpl.hpp.

Constructor & Destructor Documentation

◆ QuantizedMultiplierSmallerThanOne()

QuantizedMultiplierSmallerThanOne ( float multiplier )

Constructs a QuantizedMultiplierSmallerThanOne which will multiply by the given multiplier.

This stores the appropriate integer quantities (derived from the given multiplier) for later use. The implementation of this function is adapted from Android NN's QuantizeMultiplierSmallerThanOne().

Definition at line 16 of file ConvImpl.cpp.

References ARMNN_ASSERT.

 {
     ARMNN_ASSERT(multiplier >= 0.0f && multiplier < 1.0f);
     if (multiplier == 0.0f)
     {
         m_Multiplier = 0;
         m_RightShift = 0;
     }
     else
     {
         const double q = std::frexp(multiplier, &m_RightShift);
         m_RightShift = -m_RightShift;
         int64_t qFixed = static_cast<int64_t>(::round(q * (1ll << 31)));
         ARMNN_ASSERT(qFixed <= (1ll << 31));
         if (qFixed == (1ll << 31))
         {
             qFixed /= 2;
             --m_RightShift;
         }
         ARMNN_ASSERT(m_RightShift >= 0);
         ARMNN_ASSERT(qFixed <= std::numeric_limits<int32_t>::max());
         m_Multiplier = static_cast<int32_t>(qFixed);
     }
 }

Member Function Documentation

◆ operator*()

int32_t operator* ( int32_t rhs ) const

The implementation of this function is adapted from Android NN's MultiplyByQuantizedMultiplierSmallerThanOne().

Definition at line 41 of file ConvImpl.cpp.