dlls/krnl386.exe16/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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include <stdlib.h>
  23 #include "dosexe.h"
  24 #include "wine/debug.h"
  25
  26 WINE_DEFAULT_DEBUG_CHANNEL(int);
  27
  28 /*
  29  *  The actual work is done by a single routine.
  30  */
  31
  32 static void FPU_ModifyCode(CONTEXT86 *context, BYTE Opcode);
  33
  34
  35 /**********************************************************************
  36  *          DOSVM_Int34Handler
  37  *
  38  * Handler for int 34 (FLOATING POINT EMULATION - Opcode 0xd8).
  39  *
  40  *  The interrupt list isn't specific about what this interrupt
  41  *  actually does. [ interrup.m ]
  42  */
  43 void WINAPI DOSVM_Int34Handler(CONTEXT86 *context)
  44 {
  45     TRACE("Int 0x34 called-- FP opcode 0xd8\n");
  46     FPU_ModifyCode(context, 0xd8);
  47 }
  48
  49
  50 /**********************************************************************
  51  *          DOSVM_Int35Handler
  52  *
  53  * Handler for int 35 (FLOATING POINT EMULATION - Opcode 0xd9).
  54  *
  55  *  The interrupt list isn't specific about what this interrupt
  56  *  actually does. [ interrup.m ]
  57  */
  58 void WINAPI DOSVM_Int35Handler(CONTEXT86 *context)
  59 {
  60     TRACE("Int 0x35 called-- FP opcode 0xd9\n");
  61     FPU_ModifyCode(context, 0xd9);
  62 }
  63
  64
  65 /**********************************************************************
  66  *          DOSVM_Int36Handler
  67  *
  68  * Handler for int 36 (FLOATING POINT EMULATION - Opcode 0xda).
  69  *
  70  *  The interrupt list isn't specific about what this interrupt
  71  *  actually does. [ interrup.m ]
  72  */
  73 void WINAPI DOSVM_Int36Handler(CONTEXT86 *context)
  74 {
  75     TRACE("Int 0x36 called-- FP opcode 0xda\n");
  76     FPU_ModifyCode(context, 0xda);
  77 }
  78
  79
  80 /**********************************************************************
  81  *          DOSVM_Int37Handler
  82  *
  83  * Handler for int 37 (FLOATING POINT EMULATION - Opcode 0xdb).
  84  *
  85  *  The interrupt list isn't specific about what this interrupt
  86  *  actually does. [ interrup.m ]
  87  */
  88 void WINAPI DOSVM_Int37Handler(CONTEXT86 *context)
  89 {
  90     TRACE("Int 0x37 called-- FP opcode 0xdb\n");
  91     FPU_ModifyCode(context, 0xdb);
  92 }
  93
  94
  95 /**********************************************************************
  96  *          DOSVM_Int38Handler
  97  *
  98  * Handler for int 38 (FLOATING POINT EMULATION - Opcode 0xdc).
  99  *
 100  *  Between versions 3.0 and 5.01, the original PC-MOS API call that
 101  *  was here was moved to int 0xd4.
 102  *
 103  *  The interrupt list isn't specific about what this interrupt
 104  *  actually does. [ interrup.m ]
 105  */
 106 void WINAPI DOSVM_Int38Handler(CONTEXT86 *context)
 107 {
 108     TRACE("Int 0x38 called-- FP opcode 0xdc\n");
 109     FPU_ModifyCode(context, 0xdc);
 110 }
 111
 112
 113 /**********************************************************************
 114  *          DOSVM_Int39Handler
 115  *
 116  * Handler for int 39 (FLOATING POINT EMULATION - Opcode 0xdd).
 117  *
 118  *  The interrupt list isn't specific about what this interrupt
 119  *  actually does. [ interrup.m ]
 120  */
 121 void WINAPI DOSVM_Int39Handler(CONTEXT86 *context)
 122 {
 123     TRACE("Int 0x39 called-- FP opcode 0xdd\n");
 124     FPU_ModifyCode(context, 0xdd);
 125 }
 126
 127
 128 /**********************************************************************
 129  *          DOSVM_Int3aHandler
 130  *
 131  * Handler for int 3a (FLOATING POINT EMULATION - Opcode 0xde).
 132  *
 133  *  The interrupt list isn't specific about what this interrupt
 134  *  actually does. [ interrup.m ]
 135  */
 136 void WINAPI DOSVM_Int3aHandler(CONTEXT86 *context)
 137 {
 138     TRACE("Int 0x3a called-- FP opcode 0xde\n");
 139     FPU_ModifyCode(context, 0xde);
 140 }
 141
 142
 143 /**********************************************************************
 144  *          DOSVM_Int3bHandler
 145  *
 146  * Handler for int 3B (FLOATING POINT EMULATION - Opcode 0xdf).
 147  *
 148  *  The interrupt list isn't specific about what this interrupt
 149  *  actually does. [ interrup.m ]
 150  */
 151 void WINAPI DOSVM_Int3bHandler(CONTEXT86 *context)
 152 {
 153     TRACE("Int 0x3b called-- FP opcode 0xdf\n");
 154     FPU_ModifyCode(context, 0xdf);
 155 }
 156
 157
 158 /**********************************************************************
 159  *          DOSVM_Int3cHandler
 160  *
 161  * Handler for int 3C (FLOATING POINT EMULATION - INSTRUCTIONS WITH SEGMENT OVERRIDE).
 162  *
 163  *  Generated code is CD 3C xy mm ... (CD = int | 3C = this interrupt)
 164  *   xy is a modified ESC code and mm is the modR/M byte.
 165  *   xy byte seems to be encoded as ss011xxx  or ss000xxx
 166  *   ss= segment override.
 167  *     00 -> DS
 168  *     01 -> SS
 169  *     10 -> CS
 170  *     11 -> ES
 171  *
 172  *  11011xxx should be the opcode instruction.
 173  */
 174 void WINAPI DOSVM_Int3cHandler(CONTEXT86 *context)
 175 {
 176     FIXME("Int 3C NOT Implemented\n");
 177     INT_BARF(context, 0x3c);
 178 }
 179
 180
 181 /**********************************************************************
 182  *          DOSVM_Int3dHandler
 183  *
 184  * Handler for int 3D (FLOATING POINT EMULATION - Standalone FWAIT).
 185  *
 186  *  Opcode 0x90 is a NOP.  It just fills space where the 3D was.
 187  */
 188 void WINAPI DOSVM_Int3dHandler(CONTEXT86 *context)
 189 {
 190     TRACE("Int 0x3d called-- Standalone FWAIT\n");
 191     FPU_ModifyCode(context, 0x90);
 192 }
 193
 194
 195 /**********************************************************************
 196  *          DOSVM_Int3eHandler
 197  *
 198  * FLOATING POINT EMULATION -- Borland "Shortcut" call.
 199  *  The two bytes following the int 3E instruction are
 200  *  the subcode and a NOP ( 0x90 ), except for subcodes DC and DE
 201  *  where the second byte is the register count.
 202  *
 203  *  Direct access 4.0 modifies and does not restore this vector.
 204  *
 205  */
 206 void WINAPI DOSVM_Int3eHandler(CONTEXT86 *context)
 207 {
 208     FIXME("Int 3E NOT Implemented\n");
 209     INT_BARF(context, 0x3e);
 210 }
 211
 212
 213 /**********************************************************************
 214  *          FPU_ModifyCode
 215  *
 216  *   This is the function that inserts the 0x9b fwait instruction
 217  *   and the actual FPU opcode into the program.
 218  *           -A.C.
 219  *
 220  *               Code thanks to Ove Kaaven
 221  */
 222 static void FPU_ModifyCode(CONTEXT86 *context, BYTE Opcode)
 223 {
 224     BYTE *code = CTX_SEG_OFF_TO_LIN(context, context->SegCs, context->Eip);
 225
 226     /*
 227      * All *NIX systems should have a real or kernel emulated FPU.
 228      */
 229
 230     code[-2] = 0x9b;          /* The fwait instruction */
 231     code[-1] = Opcode;        /* Insert the opcode     */
 232
 233     if ( ISV86(context) && LOWORD(context->Eip) < 2 )
 234         FIXME("Backed up over a real mode segment boundary in FPU code.\n");
 235
 236     context->Eip -= 2; /* back up the return address 2 bytes */
 237
 238     TRACE("Modified code in FPU int call to 0x9b 0x%x\n",Opcode);
 239 }