LXR darwin-xnu/osfmk/i386/fpu.h

   1/*
   2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3 *
   4 * @APPLE_LICENSE_HEADER_START@
   5 * 
   6 * The contents of this file constitute Original Code as defined in and
   7 * are subject to the Apple Public Source License Version 1.1 (the
   8 * "License").  You may not use this file except in compliance with the
   9 * License.  Please obtain a copy of the License at
  10 * http://www.apple.com/publicsource and read it before using this file.
  11 * 
  12 * This Original Code and all software distributed under the License are
  13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17 * License for the specific language governing rights and limitations
  18 * under the License.
  19 * 
  20 * @APPLE_LICENSE_HEADER_END@
  21 */
  22/*
  23 * @OSF_COPYRIGHT@
  24 */
  25/* 
  26 * Mach Operating System
  27 * Copyright (c) 1991 Carnegie Mellon University
  28 * All Rights Reserved.
  29 * 
  30 * Permission to use, copy, modify and distribute this software and its
  31 * documentation is hereby granted, provided that both the copyright
  32 * notice and this permission notice appear in all copies of the
  33 * software, derivative works or modified versions, and any portions
  34 * thereof, and that both notices appear in supporting documentation.
  35 * 
  36 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39 * 
  40 * Carnegie Mellon requests users of this software to return to
  41 * 
  42 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43 *  School of Computer Science
  44 *  Carnegie Mellon University
  45 *  Pittsburgh PA 15213-3890
  46 * 
  47 * any improvements or extensions that they make and grant Carnegie Mellon 
  48 * the rights to redistribute these changes.
  49 */
  50
  51/*
  52 */
  53
  54#ifndef _I386_FPU_H_
  55#define _I386_FPU_H_
  56
  57/*
  58 * Macro definitions for routines to manipulate the
  59 * floating-point processor.
  60 */
  61
  62#include <i386/proc_reg.h>
  63#include <i386/thread.h>
  64#include <kern/kern_types.h>
  65#include <mach/i386/kern_return.h>
  66#include <mach/i386/thread_status.h>
  67
  68/*
  69 * FPU instructions.
  70 */
  71#define fninit() \
  72        __asm__ volatile("fninit")
  73
  74#define fnstcw(control) \
  75        __asm__("fnstcw %0" : "=m" (*(unsigned short *)(control)))
  76
  77#define fldcw(control) \
  78        __asm__ volatile("fldcw %0" : : "m" (*(unsigned short *) &(control)) )
  79
  80extern unsigned short           fnstsw(void);
  81
  82extern __inline__ unsigned short fnstsw(void)
  83{
  84        unsigned short status;
  85        __asm__ volatile("fnstsw %0" : "=ma" (status));
  86        return(status);
  87}
  88
  89#define fnclex() \
  90        __asm__ volatile("fnclex")
  91
  92#define fnsave(state)  \
  93        __asm__ volatile("fnsave %0" : "=m" (*state))
  94
  95#define frstor(state) \
  96        __asm__ volatile("frstor %0" : : "m" (state))
  97
  98#define fwait() \
  99        __asm__("fwait");
 100
 101#define fxrstor(addr)           __asm("fxrstor %0" : : "m" (*(addr)))     
 102#define fxsave(addr)            __asm __volatile("fxsave %0" : "=m" (*(addr)))
 103
 104#define FXSAFE() (fp_kind == FP_FXSR)
 105
 106#define fpu_load_context(pcb)
 107
 108/*
 109 * Save thread`s FPU context.
 110 * If only one CPU, we just set the task-switched bit,
 111 * to keep the new thread from using the coprocessor.
 112 * If multiple CPUs, we save the entire state.
 113 * NOTE: in order to provide backwards compatible support in the kernel. When saving SSE2 state, we also save the
 114 * FP state in it's old location. Otherwise fpu_get_state() and fpu_set_state() will stop working
 115 */
 116#define fpu_save_context(thread) \
 117    { \
 118        register struct i386_fpsave_state *ifps; \
 119        ifps = (thread)->machine.pcb->ims.ifps; \
 120        if (ifps != 0 && !ifps->fp_valid) { \
 121            /* registers are in FPU - save to memory */ \
 122            ifps->fp_valid = TRUE; \
 123            ifps->fp_save_flavor = FP_387; \
 124            if (FXSAFE()) { \
 125                fxsave(&ifps->fx_save_state); \
 126                ifps->fp_save_flavor = FP_FXSR; \
 127            } \
 128            fnsave(&ifps->fp_save_state); \
 129        } \
 130        set_ts(); \
 131    }
 132            
 133
 134
 135extern int      fp_kind;
 136
 137extern void             init_fpu(void);
 138extern void             fpu_module_init(void);
 139extern void             fpu_free(
 140                                struct i386_fpsave_state        * fps);
 141extern kern_return_t    fpu_set_state(
 142                                thread_t                        thr_act,
 143                                struct i386_float_state         * st);
 144extern kern_return_t    fpu_get_state(
 145                                thread_t                        thr_act,
 146                                struct i386_float_state         * st);
 147extern kern_return_t    fpu_set_fxstate(
 148                                thread_t                        thr_act,
 149                                struct i386_float_state         * st);
 150extern kern_return_t    fpu_get_fxstate(
 151                                thread_t                        thr_act,
 152                                struct i386_float_state         * st);
 153extern void             fpnoextflt(void);
 154extern void             fpextovrflt(void);
 155extern void             fpexterrflt(void);
 156extern void             fp_state_alloc(void);
 157extern void             fpintr(void);
 158extern void             fpflush(thread_t);
 159
 160#endif  /* _I386_FPU_H_ */
 161