MiniFloatConverter::ReduceMantissaToNbitsRounding Class Reference

#include <libminifloat.h>

Public Member Functions
float	operator() (float f) const
	ReduceMantissaToNbitsRounding (int bits)

Private Attributes
const uint32_t	mask
const uint32_t	maxn
const int	shift
const uint32_t	test

Detailed Description

Definition at line 59 of file libminifloat.h.

Constructor & Destructor Documentation

MiniFloatConverter::ReduceMantissaToNbitsRounding::ReduceMantissaToNbitsRounding ( int  bits )

inline

Definition at line 61 of file libminifloat.h.

Referenced by MiniFloatConverter::reduceMantissaToNbitsRounding().

                                                        : 
                    shift(23-bits), mask((0xFFFFFFFF >> (shift)) << (shift)), 
                    test(1 << (shift-1)), maxn((1<<bits)-2) {
                        assert(bits <= 23); // "max mantissa size is 23 bits"
                    }

Member Function Documentation

float MiniFloatConverter::ReduceMantissaToNbitsRounding::operator() ( float  f ) const

inline

Definition at line 66 of file libminifloat.h.

References constexpr, conv, f, mask, maxn, and shift.

                                                {
                    constexpr uint32_t low23 = (0x007FFFFF); // mask to keep lowest 23 bits = mantissa
                    constexpr uint32_t  hi9  = (0xFF800000); // mask to keep highest 9 bits = the rest
                    union { float flt; uint32_t i32; } conv;
                    conv.flt=f;
                    if (conv.i32 & test) { // need to round
                        uint32_t mantissa = (conv.i32 & low23) >> shift;
                        if (mantissa < maxn) mantissa++;
                        conv.i32 = (conv.i32 & hi9) | (mantissa << shift);
                    } else {
                        conv.i32 &= mask;
                    }
                    return conv.flt;
                }

Member Data Documentation

const uint32_t MiniFloatConverter::ReduceMantissaToNbitsRounding::mask

private

Definition at line 82 of file libminifloat.h.

Referenced by operator()().

const uint32_t MiniFloatConverter::ReduceMantissaToNbitsRounding::maxn

private

Definition at line 82 of file libminifloat.h.

Referenced by operator()().

const int MiniFloatConverter::ReduceMantissaToNbitsRounding::shift

private

Definition at line 81 of file libminifloat.h.

Referenced by operator()().

const uint32_t MiniFloatConverter::ReduceMantissaToNbitsRounding::test

private

Definition at line 82 of file libminifloat.h.

Referenced by edmIntegrityCheck.IntegrityCheck::report(), and edmIntegrityCheck.IntegrityCheck::structured().