3DNow! Intrinsics

Microsoft Specific

This topic contains the 3DNow! intrinsics. For each intrinsic, the header file mm3dnow.h is required.

The following table lists the 3DNow! intrinsics alphabetically.

Intrinsic

Use

_m_femms

Clears the architectural state when switching between MMX and floating-point instructions.

_m_from_float

Returns a 64-bit MMX value where the lower half is set to the floating-point, single-precision value from the source operand and the upper half is zero. There is no error return.

_m_pavgusb

Calculates the rounded averages of eight unsigned 8-bit integer values.

_m_pf2id

Converts packed floating-point, single-precision values to packed 32-bit integer values.

_m_pf2iw

Converts packed floating-point, single-precision values to packed 16-bit signed integer values using truncation.

_m_pfacc

Performs packed floating-point, single-precision accumulation.

_m_pfadd

Performs packed floating-point, single-precision addition.

_m_pfcmpeq

Compares packed floating-point, single-precision values to be equal and sets the corresponding return value to ones or zeros based on the result of the comparison.

_m_pfcmpge

Compares the first packed floating-point, single-precision value to be greater than or equal to the second one and sets the corresponding return value to ones or zeros based on the result of the comparison.

_m_pfcmpgt

Compares the first packed floating-point, single-precision value to be greater than the second one and sets the corresponding return value to ones or zeros based on the result of the comparison.

_m_pfmax

Returns the larger of the two packed floating-point, single-precision values.

_m_pfmin

Returns the smaller of the two packed floating-point, single-precision values.

_m_pfmul

Performs packed floating-point, single-precision multiplication.

_m_pfnacc

Performs packed floating-point, single-precision negative accumulation.

_m_pfpnacc

Performs packed floating-point, single-precision positive-negative accumulation.

_m_pfrcp

Performs scalar floating-point, low-precision reciprocal approximation.

_m_pfrcpit1

Performs the first intermediate step in the Newton-Raphson iteration to refine the reciprocal approximation produced by the _m_pfrcp intrinsic function.

_m_pfrcpit2

Performs the second and final step in the Newton-Raphson iteration to refine the reciprocal or reciprocal square root approximation produced by the _m_pfrcp or _m_pfsqrt intrinsic functions, respectively.

_m_pfrsqit1

Performs the first intermediate step in the Newton-Raphson iteration to refine the reciprocal square root approximation produced by _m_pfsqrt intrinsic function.

_m_pfrsqrt

Performs scalar floating-point, low-precision reciprocal square root approximation.

_m_pfsub

Performs packed floating-point, single-precision subtraction.

_m_pfsubr

Performs packed floating-point, single-precision reverse subtraction.

_m_pi2fd

Converts packed 32-bit integer values to packed floating-point, single-precision values.

_m_pi2fw

Converts packed 16-bit signed integer values to packed floating-point, single-precision values.

_m_pmulhrw

Multiplies four signed 16-bit integer values in the source operand by four signed 16-bit integer values in the destination operand.

_m_prefetch

Loads a 32-byte cache line into L1 data cache and sets the cache line state to exclusive.

_m_prefetchw

Loads a 32-byte cache line into L1 data cache and sets the cache line state to modified.

_m_pswapd

Swaps upper and lower halves of the source operand.

_m_to_float

Returns the floating-point, single-precision value from the lower half of the 64-bit MMX value in the source operand. There is no error return.

The compiler correctly ensures that an implict FEMMS is issued before any attempt to use the result of _m_to_float( ) operation.

See Also

Concepts

AMD 3DNow! Technology Overview and Intrinsics