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/*
* FPU data structures:
*/
#ifndef _ASM_X86_FPU_H
#define _ASM_X86_FPU_H
struct i387_fsave_struct {
u32 cwd; /* FPU Control Word */
u32 swd; /* FPU Status Word */
u32 twd; /* FPU Tag Word */
u32 fip; /* FPU IP Offset */
u32 fcs; /* FPU IP Selector */
u32 foo; /* FPU Operand Pointer Offset */
u32 fos; /* FPU Operand Pointer Selector */
/* 8*10 bytes for each FP-reg = 80 bytes: */
u32 st_space[20];
/* Software status information [not touched by FSAVE ]: */
u32 status;
};
struct i387_fxsave_struct {
u16 cwd; /* Control Word */
u16 swd; /* Status Word */
u16 twd; /* Tag Word */
u16 fop; /* Last Instruction Opcode */
union {
struct {
u64 rip; /* Instruction Pointer */
u64 rdp; /* Data Pointer */
};
struct {
u32 fip; /* FPU IP Offset */
u32 fcs; /* FPU IP Selector */
u32 foo; /* FPU Operand Offset */
u32 fos; /* FPU Operand Selector */
};
};
u32 mxcsr; /* MXCSR Register State */
u32 mxcsr_mask; /* MXCSR Mask */
/* 8*16 bytes for each FP-reg = 128 bytes: */
u32 st_space[32];
/* 16*16 bytes for each XMM-reg = 256 bytes: */
u32 xmm_space[64];
u32 padding[12];
union {
u32 padding1[12];
u32 sw_reserved[12];
};
} __attribute__((aligned(16)));
/*
* Software based FPU emulation state:
*/
struct i387_soft_struct {
u32 cwd;
u32 swd;
u32 twd;
u32 fip;
u32 fcs;
u32 foo;
u32 fos;
/* 8*10 bytes for each FP-reg = 80 bytes: */
u32 st_space[20];
u8 ftop;
u8 changed;
u8 lookahead;
u8 no_update;
u8 rm;
u8 alimit;
struct math_emu_info *info;
u32 entry_eip;
};
/*
* There are 16x 256-bit AVX registers named YMM0-YMM15.
* The low 128 bits are aliased to the 16 SSE registers (XMM0-XMM15)
* and are stored in 'struct i387_fxsave_struct::xmm_space[]'.
*
* The high 128 bits are stored here:
* 16x 128 bits == 256 bytes.
*/
struct ymmh_struct {
u8 ymmh_space[256];
};
/* We don't support LWP yet: */
struct lwp_struct {
u8 reserved[128];
};
/* Intel MPX support: */
struct bndreg {
u64 lower_bound;
u64 upper_bound;
} __packed;
struct bndcsr {
u64 bndcfgu;
u64 bndstatus;
} __packed;
struct xstate_header {
u64 xfeatures;
u64 xcomp_bv;
u64 reserved[6];
} __attribute__((packed));
struct xsave_struct {
struct i387_fxsave_struct i387;
struct xstate_header header;
struct ymmh_struct ymmh;
struct lwp_struct lwp;
struct bndreg bndreg[4];
struct bndcsr bndcsr;
/* New processor state extensions will go here. */
} __attribute__ ((packed, aligned (64)));
union thread_xstate {
struct i387_fsave_struct fsave;
struct i387_fxsave_struct fxsave;
struct i387_soft_struct soft;
struct xsave_struct xsave;
};
struct fpu {
/*
* Records the last CPU on which this context was loaded into
* FPU registers. (In the lazy-switching case we might be
* able to reuse FPU registers across multiple context switches
* this way, if no intermediate task used the FPU.)
*
* A value of -1 is used to indicate that the FPU state in context
* memory is newer than the FPU state in registers, and that the
* FPU state should be reloaded next time the task is run.
*/
unsigned int last_cpu;
unsigned int fpregs_active;
union thread_xstate state;
/*
* This counter contains the number of consecutive context switches
* during which the FPU stays used. If this is over a threshold, the
* lazy fpu saving logic becomes unlazy, to save the trap overhead.
* This is an unsigned char so that after 256 iterations the counter
* wraps and the context switch behavior turns lazy again; this is to
* deal with bursty apps that only use the FPU for a short time:
*/
unsigned char counter;
/*
* This flag indicates whether this context is fpstate_active: if the task is
* not running then we can restore from this context, if the task
* is running then we should save into this context.
*/
unsigned char fpstate_active;
};
#endif /* _ASM_X86_FPU_H */
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