freebsd-nq/sys/gnu/i386/fpemul/load_store.c
Rich Murphey b95c0fbacd Copyright changes per the author.
Added specific permissions for redistribution with FreeBSD and NetBSD.
Fixed author's email address.
1994-06-10 07:45:04 +00:00

270 lines
8.8 KiB
C

/*
* load_store.c
*
* This file contains most of the code to interpret the FPU instructions
* which load and store from user memory.
*
*
* Copyright (C) 1992,1993,1994
* W. Metzenthen, 22 Parker St, Ormond, Vic 3163,
* Australia. E-mail billm@vaxc.cc.monash.edu.au
* All rights reserved.
*
* This copyright notice covers the redistribution and use of the
* FPU emulator developed by W. Metzenthen. It covers only its use
* in the 386BSD, FreeBSD and NetBSD operating systems. Any other
* use is not permitted under this copyright.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must include information specifying
* that source code for the emulator is freely available and include
* either:
* a) an offer to provide the source code for a nominal distribution
* fee, or
* b) list at least two alternative methods whereby the source
* can be obtained, e.g. a publically accessible bulletin board
* and an anonymous ftp site from which the software can be
* downloaded.
* 3. All advertising materials specifically mentioning features or use of
* this emulator must acknowledge that it was developed by W. Metzenthen.
* 4. The name of W. Metzenthen may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* W. METZENTHEN BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*
* The purpose of this copyright, based upon the Berkeley copyright, is to
* ensure that the covered software remains freely available to everyone.
*
* The software (with necessary differences) is also available, but under
* the terms of the GNU copyleft, for the Linux operating system and for
* the djgpp ms-dos extender.
*
* W. Metzenthen June 1994.
*
*
* $Id: load_store.c,v 1.2 1994/04/29 21:16:27 gclarkii Exp $
*
*/
/*---------------------------------------------------------------------------+
| Note: |
| The file contains code which accesses user memory. |
| Emulator static data may change when user memory is accessed, due to |
| other processes using the emulator while swapping is in progress. |
+---------------------------------------------------------------------------*/
#include "param.h"
#include "proc.h"
#include "systm.h"
#include "machine/cpu.h"
#include "machine/pcb.h"
#include "fpu_emu.h"
#include "fpu_system.h"
#include "exception.h"
#include "status_w.h"
#define _NONE_ 0 /* FPU_st0_ptr etc not needed */
#define _REG0_ 1 /* Will be storing st(0) */
#define _PUSH_ 3 /* Need to check for space to push onto stack */
#define _null_ 4 /* Function illegal or not implemented */
#define pop_0() { pop_ptr->tag = TW_Empty; top++; }
static unsigned char type_table[32] = {
_PUSH_, _PUSH_, _PUSH_, _PUSH_,
_null_, _null_, _null_, _null_,
_REG0_, _REG0_, _REG0_, _REG0_,
_REG0_, _REG0_, _REG0_, _REG0_,
_NONE_, _null_, _NONE_, _PUSH_,
_NONE_, _PUSH_, _null_, _PUSH_,
_NONE_, _null_, _NONE_, _REG0_,
_NONE_, _REG0_, _NONE_, _REG0_
};
void
load_store_instr(char type)
{
FPU_REG *pop_ptr; /* We need a version of FPU_st0_ptr which
* won't change. */
pop_ptr = NULL; /* Initialized just to stop compiler warnings. */
switch (type_table[(int) (unsigned) type]) {
case _NONE_:
break;
case _REG0_:
pop_ptr = &st(0); /* Some of these instructions pop
* after storing */
FPU_st0_ptr = pop_ptr; /* Set the global variables. */
FPU_st0_tag = FPU_st0_ptr->tag;
break;
case _PUSH_:
{
pop_ptr = &st(-1);
if (pop_ptr->tag != TW_Empty) {
stack_overflow();
return;
}
top--;
}
break;
case _null_:
return Un_impl();
#ifdef PARANOID
default:
return EXCEPTION(EX_INTERNAL);
#endif /* PARANOID */
}
switch (type) {
case 000: /* fld m32real */
reg_load_single();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 001: /* fild m32int */
reg_load_int32();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 002: /* fld m64real */
reg_load_double();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 003: /* fild m16int */
reg_load_int16();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 010: /* fst m32real */
reg_store_single();
break;
case 011: /* fist m32int */
reg_store_int32();
break;
case 012: /* fst m64real */
reg_store_double();
break;
case 013: /* fist m16int */
reg_store_int16();
break;
case 014: /* fstp m32real */
if (reg_store_single())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
case 015: /* fistp m32int */
if (reg_store_int32())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
case 016: /* fstp m64real */
if (reg_store_double())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
case 017: /* fistp m16int */
if (reg_store_int16())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
case 020: /* fldenv m14/28byte */
fldenv();
break;
case 022: /* frstor m94/108byte */
frstor();
break;
case 023: /* fbld m80dec */
reg_load_bcd();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 024: /* fldcw */
REENTRANT_CHECK(OFF);
control_word = fuword((unsigned short *) FPU_data_address);
REENTRANT_CHECK(ON);
#ifdef NO_UNDERFLOW_TRAP
if (!(control_word & EX_Underflow)) {
control_word |= EX_Underflow;
}
#endif
FPU_data_address = (void *) data_operand_offset; /* We want no net effect */
FPU_entry_eip = ip_offset; /* We want no net effect */
break;
case 025: /* fld m80real */
reg_load_extended();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 027: /* fild m64int */
reg_load_int64();
setcc(0); /* Clear the SW_C1 bit, "other bits undefined" */
reg_move(&FPU_loaded_data, pop_ptr);
break;
case 030: /* fstenv m14/28byte */
fstenv();
FPU_data_address = (void *) data_operand_offset; /* We want no net effect */
FPU_entry_eip = ip_offset; /* We want no net effect */
break;
case 032: /* fsave */
fsave();
FPU_data_address = (void *) data_operand_offset; /* We want no net effect */
FPU_entry_eip = ip_offset; /* We want no net effect */
break;
case 033: /* fbstp m80dec */
if (reg_store_bcd())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
case 034: /* fstcw m16int */
REENTRANT_CHECK(OFF);
/* verify_area(VERIFY_WRITE, FPU_data_address, 2);*/
suword( (short *) FPU_data_address,control_word);
REENTRANT_CHECK(ON);
FPU_data_address = (void *) data_operand_offset; /* We want no net effect */
FPU_entry_eip = ip_offset; /* We want no net effect */
break;
case 035: /* fstp m80real */
if (reg_store_extended())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
case 036: /* fstsw m2byte */
status_word &= ~SW_Top;
status_word |= (top & 7) << SW_Top_Shift;
REENTRANT_CHECK(OFF);
/* verify_area(VERIFY_WRITE, FPU_data_address, 2);*/
suword( (short *) FPU_data_address,status_word);
REENTRANT_CHECK(ON);
FPU_data_address = (void *) data_operand_offset; /* We want no net effect */
FPU_entry_eip = ip_offset; /* We want no net effect */
break;
case 037: /* fistp m64int */
if (reg_store_int64())
pop_0();/* pop only if the number was actually stored
* (see the 80486 manual p16-28) */
break;
}
}