NetBSD/sys/arch/x86_64/include/fpu.h

85 lines
2.2 KiB
C

/* $NetBSD: fpu.h,v 1.2 2002/01/03 04:28:31 thorpej Exp $ */
#ifndef _X86_64_FPU_H_
#define _X86_64_FPU_H_
/*
* NetBSD/x86_64 only uses the extended save/restore format used
* by fxsave/fsrestore, to always deal with the SSE registers,
* which are part of the ABI to pass floating point values.
*/
struct fxsave64 {
/*BITFIELDTYPE*/ u_int64_t fx_fcw:16;
/*BITFIELDTYPE*/ u_int64_t fx_fsw:16;
/*BITFIELDTYPE*/ u_int64_t fx_unused1:8;
/*BITFIELDTYPE*/ u_int64_t fx_ftw:8;
/*BITFIELDTYPE*/ u_int64_t fx_fop:16;
/*BITFIELDTYPE*/ u_int64_t fx_rip;
/*BITFIELDTYPE*/ u_int64_t fx_dp;
/*BITFIELDTYPE*/ u_int64_t fx_mxcsr:32;
/*BITFIELDTYPE*/ u_int64_t fx_unused2:32;
/*BITFIELDTYPE*/ u_int64_t fx_st[8 * 2]; /* 8 normal FP regs */
/*BITFIELDTYPE*/ u_int64_t fx_xmm[16 * 2]; /* 16 SSE2 registers */
/*BITFIELDTYPE*/ u_int8_t fx_unused3[96];
} __attribute__ ((aligned (16)));
/*
* This one only used for backward compat coredumping.
*/
struct oldfsave {
u_int16_t fs_control;
u_int16_t fs_unused0;
u_int16_t fs_status;
u_int16_t fs_unused1;
u_int16_t fs_tag;
u_int16_t fs_unused2;
u_int32_t fs_ipoff;
u_int16_t fs_ipsel;
u_int16_t fs_op;
u_int32_t fs_opoff;
u_int16_t fs_opsel;
} __attribute__ ((packed));
/*
* The i387 defaults to Intel extended precision mode and round to nearest,
* with all exceptions masked.
* XXXfvdl check this. This stuff is probably invalid.
*/
#define __INITIAL_NPXCW__ 0x037f
/* NetBSD uses IEEE double precision. */
#define __NetBSD_NPXCW__ 0x127f
/* Linux just uses the default control word. */
#define __Linux_NPXCW__ 0x037f
/*
* The standard control word from finit is 0x37F, giving:
* round to nearest
* 64-bit precision
* all exceptions masked.
*
* Now we want:
* affine mode (if we decide to support 287's)
* round to nearest
* 53-bit precision
* all exceptions masked.
*
* 64-bit precision often gives bad results with high level languages
* because it makes the results of calculations depend on whether
* intermediate values are stored in memory or in FPU registers.
*/
/*
* XXX
*/
struct trapframe;
extern void fpuinit(void);
extern void fpudrop(void);
extern void fpusave(void);
extern void fputrap(struct trapframe *);
extern struct proc *fpuproc;
#endif /* _X86_64_FPU_H_ */