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Diffstat (limited to 'sys/gnu/fpemul/load_store.c')
| -rw-r--r-- | sys/gnu/fpemul/load_store.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/sys/gnu/fpemul/load_store.c b/sys/gnu/fpemul/load_store.c new file mode 100644 index 000000000000..a86a2fd3ec82 --- /dev/null +++ b/sys/gnu/fpemul/load_store.c @@ -0,0 +1,269 @@ +/* + * 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 1.3 1994/06/10 07:44:30 rich 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; + } +} |