FPU::State Struct Reference

512 byte structure for FPU / MMX / SSE registers corresponds to the layout used by the instructions fxsave and fxrstor. More...

#include <machine/fpu.h>

Collaboration diagram for FPU::State:

Classes
struct	ST
	80 bit registers for FPU stack / MMX More...
struct	XMM
	128 bit SSE registers More...

Public Member Functions
void	init ()
	Set structure to the initial FPU state Clears the FPU state (but its not just zeroed!)
void	save ()
	Save the current FPU (+ MMX + SSE) state into this structure. More...
void	restore ()
	Restore the saved FPU (+ MMX + SSE) state from this structure. More...

Public Attributes
uint16_t	fcw
	FPU Control Word.
uint16_t	fsw
	FPU Status Word.
uint8_t	ftw
	FPU Tag Word.
uint16_t	__pad0__: 0
	(16 bit alignment)
uint16_t	fop
	FPU Opcode.
union {
uint64_t	ip
struct {
uint32_t	ip_off
uint32_t	ip_seg
}
};
union {
uint64_t	dp
struct {
uint32_t	dp_off
uint32_t	dp_seg
}
};
uint32_t	mxcsr
uint32_t	mxcsr_mask
struct {
ST	value
uint64_t	__pad0__: 48
}	st [8]
XMM	xmm [16]
uint64_t	reserved [12]
	(reserved)

Detailed Description

512 byte structure for FPU / MMX / SSE registers corresponds to the layout used by the instructions fxsave and fxrstor.

See also

ISDMv1 Chapter 10.5.1 FXSAVE Area

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Class Documentation

FPU::State::ST

struct FPU::State::ST

80 bit registers for FPU stack / MMX

Class Members
uint64_t	fraction: 63
uint64_t	integer: 1
uint16_t	exponent: 15
uint16_t	sign: 1

FPU::State::XMM

struct FPU::State::XMM

128 bit SSE registers

Class Members
uint64_t	low
uint64_t	high

Member Function Documentation

save()

void FPU::State::save ( )

inline

Save the current FPU (+ MMX + SSE) state into this structure.

Note

Structure has to be 16 byte aligned

restore()

void FPU::State::restore ( )

inline

Restore the saved FPU (+ MMX + SSE) state from this structure.

Note

Structure has to be 16 byte aligned

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The documentation for this struct was generated from the following files:

• machine/fpu.h
• machine/fpu.cc