Floating-point Conversion

Overview

Supported float to fixed conversions

			bfloat16		float
Output bits	Type	Arch.	Implementation	Notes	Implementation	Notes
4b	Scalar	AIE
		AIE-ML XDNA 1	Runs on vector unit		Runs on vector unit
		XDNA 2	Runs on vector unit		Runs on vector unit
		Vector	AIE
	AIE-ML XDNA 1		Emulated	Uses aie::rounding_mode::symmetric_zero	Emulated	Uses aie::rounding_mode::symmetric_zero
	XDNA 2		Emulated	Uses aie::rounding_mode::symmetric_zero	Emulated	Uses aie::rounding_mode::symmetric_zero
	8b		Scalar	AIE			Native to 32b + cast
		AIE-ML XDNA 1		Runs on vector unit		Runs on vector unit
XDNA 2		Runs on vector unit			Runs on vector unit
Vector		AIE				Element-wise scalar
		AIE-ML XDNA 1	Emulated	Uses aie::rounding_mode::symmetric_zero	Emulated	Uses aie::rounding_mode::symmetric_zero
		XDNA 2	Emulated	Uses aie::rounding_mode::symmetric_zero	Emulated	Uses aie::rounding_mode::symmetric_zero
		16b	Scalar	AIE			Native to 32b + cast
AIE-ML XDNA 1				Runs on vector unit		Runs on vector unit
XDNA 2	Runs on vector unit				Native
Vector	AIE					Vectorized emulated impl
	AIE-ML XDNA 1		Native to 32b + extract lower 16b1	Uses aie::rounding_mode::floor	Emulated	Uses aie::rounding_mode::symmetric_zero
	XDNA 2		Native to 32b + extract lower 16b1	Uses aie::rounding_mode::floor	Emulated	Uses aie::rounding_mode::symmetric_zero
	32b		Scalar	AIE			Native
AIE-ML XDNA 1				Runs on vector unit		Runs on vector unit
XDNA 2		Runs on vector unit			Native
Vector		AIE				Vectorized emulated impl
		AIE-ML XDNA 1	Native	Uses aie::rounding_mode::floor	Emulated	Uses aie::rounding_mode::symmetric_zero
		XDNA 2	Native	Uses aie::rounding_mode::floor	Emulated	Uses aie::rounding_mode::symmetric_zero

Note

¹ - Unsigned conversions are emulated and use aie::rounding_mode::symmetric_zero.

Supported fixed to float conversions

Output type	Type	Arch.	int4	int8	int16	int32
bfloat16	Scalar	AIE
		AIE-ML XDNA 1	Runs on vector unit	Runs on vector unit	Runs on vector unit	Runs on vector unit
		XDNA 2	Runs on vector unit	Runs on vector unit	Runs on vector unit	Runs on vector unit
		Vector	AIE
	AIE-ML XDNA 1		Emulated	Emulated	Emulated	Emulated
	XDNA 2		Emulated	Emulated	Emulated	Emulated
	float		Scalar	AIE		Cast to int32 + native	Cast to int32 + native	Native
		AIE-ML XDNA 1		Runs on vector unit	Runs on vector unit	Runs on vector unit	Runs on vector unit
XDNA 2		Cast to int32 + native		Cast to int32 + native	Cast to int32 + native	Native
Vector		AIE			Element-wise scalar	Emulated	Element-wise scalar
		AIE-ML XDNA 1	Emulated	Emulated	Emulated	Emulated
		XDNA 2	Emulated	Emulated	Emulated	Emulated

Functions
template<typename TR = cint32> requires (arch::is(arch::AIE, arch::AIE_ML) && Utils::is_one_of_v<TR, cint16, cint32>)
auto	aie::to_fixed (cfloat a, int shift=0)
	Convert a floating point value into a fixed-point value.
template<typename TR = int32, unsigned Elems> requires (arch::is(arch::Gen2))
auto	aie::to_fixed (const vector< bfloat16, Elems > &v, int shift=0) -> vector< TR, Elems >
	Convert the elements in a bfloat16 vector into fixed-point values.
template<typename TR = cint32, unsigned Elems> requires ((arch::is(arch::AIE) || (arch::is(arch::AIE_ML) && __AIE_API_COMPLEX_FP32_EMULATION__ == 1)) && Utils::is_one_of_v<TR, cint16, cint32>)
auto	aie::to_fixed (const vector< cfloat, Elems > &v, int shift=0) -> vector< TR, Elems >
	Convert the elements in a floating point vector into fixed-point values.
template<typename TR = int32, unsigned Elems> requires ((arch::is(arch::Gen2) && Utils::is_one_of_v<TR, int4, uint4, int8, uint8, int16, uint16, int32, uint32>) || (arch::is(arch::Gen1) && Utils::is_one_of_v<TR, int16, int32>))
auto	aie::to_fixed (const vector< float, Elems > &v, int shift=0) -> vector< TR, Elems >
	Convert the elements in a floating point vector into fixed-point values.
template<typename TR = int32> requires (Utils::is_one_of_v<TR, int8, int16, int32>)
auto	aie::to_fixed (float a, int shift=0)
	Convert a floating point value into a fixed-point value.
template<typename TR = float, Accum Acc> requires (std::is_same_v<TR, float> && arch::is(arch::Gen2))
auto	aie::to_float (const Acc &acc, int shift=0) -> vector< TR, Acc::size()>
	Convert the elements in a real fixed-point accumulator into floating point values.
template<typename TR = float, VectorOrOp Vec> requires ((arch::is(arch::Gen2) && Utils::is_one_of_v<typename Vec::value_type, int4, uint4, int8, uint8, int16, uint16, int32, uint32>) || (arch::is(arch::Gen1) && Utils::is_one_of_v<typename Vec::value_type, int16, int32>))
auto	aie::to_float (const Vec &v, int shift=0) -> vector< TR, Vec::size()>
	Convert the elements in a real fixed-point vector into floating point values.
template<typename TR = cfloat, typename T, unsigned Elems> requires (Utils::is_one_of_v<T, cint16, cint32>)
auto	aie::to_float (const vector< T, Elems > &v, int shift=0) -> vector< TR, Elems >
	Convert the elements in a complex fixed-point vector into floating point values.
template<typename TR = float>
auto	aie::to_float (int a, int shift=0)
	Convert a fixed-point value into a floating point value.
template<typename TR = cfloat, typename T> requires (Utils::is_one_of_v<T, cint16, cint32>)
auto	aie::to_float (T a, int shift=0)
	Convert a complex fixed-point value into a floating point value.

Function Documentation

to_fixed() [1/5]

template<typename TR = cint32>
requires (arch::is(arch::AIE, arch::AIE_ML) && Utils::is_one_of_v<TR, cint16, cint32>)

auto aie::to_fixed	(	cfloat	a,
		int	shift = 0 )

Convert a floating point value into a fixed-point value.

Parameters

a	Input value.
shift	Position of the point in the output value.

Template Parameters

TR	Type of the returned fixed-point value.

to_fixed() [2/5]

template<typename TR = int32, unsigned Elems>
requires (arch::is(arch::Gen2))

auto aie::to_fixed	(	const vector< bfloat16, Elems > &	v,
		int	shift = 0 ) -> vector<TR, Elems>

Convert the elements in a bfloat16 vector into fixed-point values.

Note

This conversion performs floor rounding, regardless of the rounding_mode configured by the user.

Parameters

v	Input vector.
shift	Position of the point in the output values.

Template Parameters

TR	Type of the returned fixed-point values.

to_fixed() [3/5]

template<typename TR = cint32, unsigned Elems>
requires ((arch::is(arch::AIE) || (arch::is(arch::AIE_ML) && __AIE_API_COMPLEX_FP32_EMULATION__ == 1)) && Utils::is_one_of_v<TR, cint16, cint32>)

auto aie::to_fixed	(	const vector< cfloat, Elems > &	v,
		int	shift = 0 ) -> vector<TR, Elems>

Convert the elements in a floating point vector into fixed-point values.

Parameters

v	Input vector.
shift	Position of the point in the output values.

Template Parameters

TR	Type of the returned fixed-point values.

to_fixed() [4/5]

template<typename TR = int32, unsigned Elems>
requires ((arch::is(arch::Gen2) && Utils::is_one_of_v<TR, int4, uint4, int8, uint8, int16, uint16, int32, uint32>) || (arch::is(arch::Gen1) && Utils::is_one_of_v<TR, int16, int32>))

auto aie::to_fixed	(	const vector< float, Elems > &	v,
		int	shift = 0 ) -> vector<TR, Elems>

Convert the elements in a floating point vector into fixed-point values.

Parameters

v	Input vector.
shift	Position of the point in the output values.

Template Parameters

TR	Type of the returned fixed-point values.

to_fixed() [5/5]

template<typename TR = int32>
requires (Utils::is_one_of_v<TR, int8, int16, int32>)

auto aie::to_fixed	(	float	a,
		int	shift = 0 )

Convert a floating point value into a fixed-point value.

Parameters

a	Input value.
shift	Position of the point in the output value.

Template Parameters

TR	Type of the returned fixed-point value.

to_float() [1/5]

template<typename TR = float, Accum Acc>
requires (std::is_same_v<TR, float> && arch::is(arch::Gen2))

auto aie::to_float	(	const Acc &	acc,
		int	shift = 0 ) -> vector<TR, Acc::size()>

Convert the elements in a real fixed-point accumulator into floating point values.

Parameters

acc	Input accumulator.
shift	Position of the point in the input values.

to_float() [2/5]

template<typename TR = float, VectorOrOp Vec>
requires ((arch::is(arch::Gen2) && Utils::is_one_of_v<typename Vec::value_type, int4, uint4, int8, uint8, int16, uint16, int32, uint32>) || (arch::is(arch::Gen1) && Utils::is_one_of_v<typename Vec::value_type, int16, int32>))

auto aie::to_float	(	const Vec &	v,
		int	shift = 0 ) -> vector<TR, Vec::size()>

Convert the elements in a real fixed-point vector into floating point values.

Parameters

v	Input vector.
shift	Position of the point in the input values.

to_float() [3/5]

template<typename TR = cfloat, typename T, unsigned Elems>
requires (Utils::is_one_of_v<T, cint16, cint32>)

auto aie::to_float	(	const vector< T, Elems > &	v,
		int	shift = 0 ) -> vector<TR, Elems>

Convert the elements in a complex fixed-point vector into floating point values.

Parameters

v	Input vector.
shift	Position of the point in the input values.

to_float() [4/5]

template<typename TR = float>

auto aie::to_float	(	int	a,
		int	shift = 0 )

Convert a fixed-point value into a floating point value.

Parameters

a	Input value.
shift	Position of the point in the input value.

to_float() [5/5]

template<typename TR = cfloat, typename T>
requires (Utils::is_one_of_v<T, cint16, cint32>)

auto aie::to_float	(	T	a,
		int	shift = 0 )

Convert a complex fixed-point value into a floating point value.

Parameters

a	Input value.
shift	Position of the point in the input value.