dlls/winedos/fpu.c

   1 /*
   2  * DOS interrupt 34->3e handlers.  All FPU interrupt code should be
   3  * moved into this file.
   4  *
   5  * Copyright 2002 Robert 'Admiral' Coeyman
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <stdlib.h>
  23 #include "msdos.h"
  24 #include "miscemu.h"
  25 #include "wine/debug.h"
  26
  27 WINE_DEFAULT_DEBUG_CHANNEL(int);
  28
  29 /*
  30  *  The actual work is done by a single routine.
  31  */
  32
  33 static void FPU_ModifyCode(CONTEXT86 *context, BYTE Opcode);
  34
  35
  36 /**********************************************************************
  37  *          DOSVM_Int34Handler (WINEDOS16.152)
  38  *
  39  * Handler for int 34 (FLOATING POINT EMULATION - Opcode 0xd8).
  40  *
  41  *  The interrupt list isn't specific about what this interrupt
  42  *  actually does. [ interrup.m ]
  43  */
  44 void WINAPI DOSVM_Int34Handler(CONTEXT86 *context)
  45 {
  46     TRACE("Int 0x34 called-- FP opcode 0xd8");
  47     FPU_ModifyCode(context, 0xd8);
  48 }
  49
  50
  51 /**********************************************************************
  52  *          DOSVM_Int35Handler (WINEDOS16.153)
  53  *
  54  * Handler for int 35 (FLOATING POINT EMULATION - Opcode 0xd9).
  55  *
  56  *  The interrupt list isn't specific about what this interrupt
  57  *  actually does. [ interrup.m ]
  58  */
  59 void WINAPI DOSVM_Int35Handler(CONTEXT86 *context)
  60 {
  61     TRACE("Int 0x35 called-- FP opcode 0xd9");
  62     FPU_ModifyCode(context, 0xd9);
  63 }
  64
  65
  66 /**********************************************************************
  67  *          DOSVM_Int36Handler (WINEDOS16.154)
  68  *
  69  * Handler for int 36 (FLOATING POINT EMULATION - Opcode 0xda).
  70  *
  71  *  The interrupt list isn't specific about what this interrupt
  72  *  actually does. [ interrup.m ]
  73  */
  74 void WINAPI DOSVM_Int36Handler(CONTEXT86 *context)
  75 {
  76     TRACE("Int 0x36 called-- FP opcode 0xda");
  77     FPU_ModifyCode(context, 0xda);
  78 }
  79
  80
  81 /**********************************************************************
  82  *          DOSVM_Int37Handler (WINEDOS16.155)
  83  *
  84  * Handler for int 37 (FLOATING POINT EMULATION - Opcode 0xdb).
  85  *
  86  *  The interrupt list isn't specific about what this interrupt
  87  *  actually does. [ interrup.m ]
  88  */
  89 void WINAPI DOSVM_Int37Handler(CONTEXT86 *context)
  90 {
  91     TRACE("Int 0x37 called-- FP opcode 0xdb");
  92     FPU_ModifyCode(context, 0xdb);
  93 }
  94
  95
  96 /**********************************************************************
  97  *          DOSVM_Int38Handler (WINEDOS16.156)
  98  *
  99  * Handler for int 38 (FLOATING POINT EMULATION - Opcode 0xdc).
 100  *
 101  *  Between versions 3.0 and 5.01, the original PC-MOS API call that
 102  *  was here was moved to int 0xd4.
 103  *
 104  *  The interrupt list isn't specific about what this interrupt
 105  *  actually does. [ interrup.m ]
 106  */
 107 void WINAPI DOSVM_Int38Handler(CONTEXT86 *context)
 108 {
 109     TRACE("Int 0x38 called-- FP opcode 0xdc");
 110     FPU_ModifyCode(context, 0xdc);
 111 }
 112
 113
 114 /**********************************************************************
 115  *          DOSVM_Int39Handler (WINEDOS16.157)
 116  *
 117  * Handler for int 39 (FLOATING POINT EMULATION - Opcode 0xdd).
 118  *
 119  *  The interrupt list isn't specific about what this interrupt
 120  *  actually does. [ interrup.m ]
 121  */
 122 void WINAPI DOSVM_Int39Handler(CONTEXT86 *context)
 123 {
 124     TRACE("Int 0x39 called-- FP opcode 0xdd");
 125     FPU_ModifyCode(context, 0xdd);
 126 }
 127
 128
 129 /**********************************************************************
 130  *          DOSVM_Int3aHandler (WINEDOS16.158)
 131  *
 132  * Handler for int 3a (FLOATING POINT EMULATION - Opcode 0xde).
 133  *
 134  *  The interrupt list isn't specific about what this interrupt
 135  *  actually does. [ interrup.m ]
 136  */
 137 void WINAPI DOSVM_Int3aHandler(CONTEXT86 *context)
 138 {
 139     TRACE("Int 0x3a called-- FP opcode 0xde");
 140     FPU_ModifyCode(context, 0xde);
 141 }
 142
 143
 144 /**********************************************************************
 145  *          DOSVM_Int3bHandler (WINEDOS16.159)
 146  *
 147  * Handler for int 3B (FLOATING POINT EMULATION - Opcode 0xdf).
 148  *
 149  *  The interrupt list isn't specific about what this interrupt
 150  *  actually does. [ interrup.m ]
 151  */
 152 void WINAPI DOSVM_Int3bHandler(CONTEXT86 *context)
 153 {
 154     TRACE("Int 0x3b called-- FP opcode 0xdf");
 155     FPU_ModifyCode(context, 0xdf);
 156 }
 157
 158
 159 /**********************************************************************
 160  *          DOSVM_Int3cHandler (WINEDOS16.160)
 161  *
 162  * Handler for int 3C (FLOATING POINT EMULATION - INSTRUCTIONS WITH SEGMENT OVERRIDE).
 163  *
 164  *  Generated code is CD 3C xy mm ... (CD = int | 3C = this interrupt)
 165  *   xy is a modified ESC code and mm is the modR/M byte.
 166  *   xy byte seems to be encoded as ss011xxx  or ss000xxx
 167  *   ss= segment override.
 168  *     00 -> DS
 169  *     01 -> SS
 170  *     10 -> CS
 171  *     11 -> ES
 172  *
 173  *  11011xxx should be the opcode instruction.
 174  */
 175 void WINAPI DOSVM_Int3cHandler(CONTEXT86 *context)
 176 {
 177     FIXME("Int 3C NOT Implemented");
 178     INT_BARF(context, 0x3c);
 179 }
 180
 181
 182 /**********************************************************************
 183  *          DOSVM_Int3dHandler (WINEDOS16.161)
 184  *
 185  * Handler for int 3D (FLOATING POINT EMULATION - Standalone FWAIT).
 186  *
 187  *  Opcode 0x90 is a NOP.  It just fills space where the 3D was.
 188  */
 189 void WINAPI DOSVM_Int3dHandler(CONTEXT86 *context)
 190 {
 191     TRACE("Int 0x3d called-- Standalone FWAIT");
 192     FPU_ModifyCode(context, 0x90);
 193 }
 194
 195
 196 /**********************************************************************
 197  *          DOSVM_Int3eHandler (WINEDOS16.162)
 198  *
 199  * FLOATING POINT EMULATION -- Borland "Shortcut" call.
 200  *  The two bytes following the int 3E instruction are
 201  *  the subcode and a NOP ( 0x90 ), except for subcodes DC and DE
 202  *  where the second byte is the register count.
 203  *
 204  *  Direct access 4.0 modifies and does not restore this vector.
 205  *
 206  */
 207 void WINAPI DOSVM_Int3eHandler(CONTEXT86 *context)
 208 {
 209     FIXME("Int 3E NOT Implemented");
 210     INT_BARF(context, 0x3e);
 211 }
 212
 213
 214 /**********************************************************************
 215  *          FPU_ModifyCode
 216  *
 217  *   This is the function that inserts the 0x9b fwait instruction
 218  *   and the actual FPU opcode into the program.
 219  *           -A.C.
 220  *
 221  *               Code thanks to Ove Kaaven
 222  */
 223 static void FPU_ModifyCode(CONTEXT86 *context, BYTE Opcode)
 224 {
 225     WORD *stack = CTX_SEG_OFF_TO_LIN(context, context->SegSs, context->Esp);
 226     BYTE *code =  CTX_SEG_OFF_TO_LIN(context, stack[1], stack[0]);
 227
 228     /*
 229      * All *NIX systems should have a real or kernel emulated FPU.
 230      */
 231
 232     code[-2] = 0x9b;          /* The fwait instruction */
 233     code[-1] = Opcode;        /* Insert the opcode     */
 234
 235     if ( stack[0] < 2 ) FIXME("Backed up over a segment boundry in FPU code.");
 236
 237     stack[0] -= 2;             /* back up the return address 2 bytes */
 238
 239     TRACE("Modified code in FPU int call to 0x9b 0x%x",Opcode);
 240 }