dlls/win87em/emulate.c

   1 #include <stdlib.h>
   2 #include "miscemu.h"
   3 #include "debugtools.h"
   4
   5 DEFAULT_DEBUG_CHANNEL(int)
   6
   7 struct Win87EmInfoStruct
   8 {
   9     unsigned short Version;
  10     unsigned short SizeSaveArea;
  11     unsigned short WinDataSeg;
  12     unsigned short WinCodeSeg;
  13     unsigned short Have80x87;
  14     unsigned short Unused;
  15 };
  16
  17 /* Implementing this is easy cause Linux and *BSD* ALWAYS have a numerical
  18  * coprocessor. (either real or emulated on kernellevel)
  19  */
  20 /* win87em.dll also sets interrupt vectors: 2 (NMI), 0x34 - 0x3f (emulator
  21  * calls of standard libraries, see Ralph Browns interrupt list), 0x75
  22  * (int13 error reporting of coprocessor)
  23  */
  24
  25 /* have a look at /usr/src/linux/arch/i386/math-emu/ *.[ch] for more info
  26  * especially control_w.h and status_w.h
  27  */
  28 /* FIXME: Still rather skeletal implementation only */
  29
  30 static BOOL Installed = 0;
  31 static WORD RefCount = 0;
  32 static WORD CtrlWord_1 = 0;
  33 static WORD CtrlWord_2 = 0;
  34 static WORD CtrlWord_Internal = 0;
  35 static WORD StatusWord_1 = 0x000b;
  36 static WORD StatusWord_2 = 0;
  37 static WORD StatusWord_3 = 0;
  38 static WORD StackTop = 175;
  39 static WORD StackBottom = 0;
  40 static WORD Inthandler02hVar = 1;
  41
  42 void WIN87_ClearCtrlWord( CONTEXT86 *context )
  43 {
  44     AX_reg(context) = 0;
  45     if (Installed)
  46 #ifdef __i386__
  47         __asm__("fclex");
  48 #else
  49         ;
  50 #endif
  51     StatusWord_3 = StatusWord_2 = 0;
  52 }
  53
  54 void WIN87_SetCtrlWord( CONTEXT86 *context )
  55 {
  56     CtrlWord_1 = AX_reg(context);
  57     AX_reg(context) &= 0xff3c;
  58     if (Installed) {
  59         CtrlWord_Internal = AX_reg(context);
  60 #ifdef __i386__
  61         __asm__("wait;fldcw %0" : : "m" (CtrlWord_Internal));
  62 #endif
  63     }
  64     CtrlWord_2 = AX_reg(context);
  65 }
  66
  67 void WIN87_Init( CONTEXT86 *context )
  68 {
  69     if (Installed) {
  70 #ifdef __i386__
  71         __asm__("fninit");
  72         __asm__("fninit");
  73 #endif
  74     }
  75     StackBottom = StackTop;
  76     AX_reg(context) = 0x1332;
  77     WIN87_SetCtrlWord(context);
  78     WIN87_ClearCtrlWord(context);
  79 }
  80
  81 void WINAPI WIN87_fpmath( CONTEXT86 *context )
  82 {
  83     TRACE("(cs:eip=%x:%lx es=%x bx=%04x ax=%04x dx==%04x)\n",
  84                  (WORD)CS_reg(context), EIP_reg(context),
  85                  (WORD)ES_reg(context), BX_reg(context),
  86                  AX_reg(context), DX_reg(context) );
  87
  88     switch(BX_reg(context))
  89     {
  90     case 0: /* install (increase instanceref) emulator, install NMI vector */
  91         RefCount++;
  92         if (Installed)
  93             /* InstallIntVecs02hAnd75h(); */    ;
  94         WIN87_Init(context);
  95         AX_reg(context) = 0;
  96         break;
  97
  98     case 1: /* Init Emulator */
  99         WIN87_Init(context);
 100         break;
 101
 102     case 2: /* deinstall emulator (decrease instanceref), deinstall NMI vector
 103              * if zero. Every '0' call should have a matching '2' call.
 104              */
 105         WIN87_Init(context);
 106         if (!(--RefCount) && (Installed))
 107             /* RestoreInt02h() */   ;
 108
 109         break;
 110
 111     case 3:
 112         /*INT_SetHandler(0x3E,MAKELONG(AX,DX));*/
 113         break;
 114
 115     case 4: /* set control word (& ~(CW_Denormal|CW_Invalid)) */
 116         /* OUT: newset control word in AX */
 117         WIN87_SetCtrlWord(context);
 118         break;
 119
 120     case 5: /* return internal control word in AX */
 121         AX_reg(context) = CtrlWord_1;
 122         break;
 123
 124     case 6: /* round top of stack to integer using method AX & 0x0C00 */
 125         /* returns current controlword */
 126         {
 127             DWORD dw=0;
 128             WORD save,mask;
 129             /* I don't know much about asm() programming. This could be
 130              * wrong.
 131              */
 132 #ifdef __i386__
 133            __asm__ __volatile__("fstcw %0;wait" : "=m" (save) : : "memory");
 134            __asm__ __volatile__("fstcw %0;wait" : "=m" (mask) : : "memory");
 135            __asm__ __volatile__("orw $0xC00,%0" : "=m" (mask) : : "memory");
 136            __asm__ __volatile__("fldcw %0;wait" : : "m" (mask));
 137            __asm__ __volatile__("frndint");
 138            __asm__ __volatile__("fist %0;wait" : "=m" (dw) : : "memory");
 139            __asm__ __volatile__("fldcw %0" : : "m" (save));
 140 #endif
 141             TRACE("On top of stack is %ld\n",dw);
 142         }
 143         break;
 144
 145     case 7: /* POP top of stack as integer into DX:AX */
 146         /* IN: AX&0x0C00 rounding protocol */
 147         /* OUT: DX:AX variable popped */
 148         {
 149             DWORD dw=0;
 150             /* I don't know much about asm() programming. This could be
 151              * wrong.
 152              */
 153 /* FIXME: could someone who really understands asm() fix this please? --AJ */
 154 /*            __asm__("fistp %0;wait" : "=m" (dw) : : "memory"); */
 155             TRACE("On top of stack was %ld\n",dw);
 156             AX_reg(context) = LOWORD(dw);
 157             DX_reg(context) = HIWORD(dw);
 158         }
 159         break;
 160
 161     case 8: /* restore internal status words from emulator status word */
 162         AX_reg(context) = 0;
 163         if (Installed) {
 164 #ifdef __i386__
 165             __asm__("fstsw %0;wait" : "=m" (StatusWord_1));
 166 #endif
 167             AL_reg(context) = (BYTE)StatusWord_1 & 0x3f;
 168         }
 169         AX_reg(context) |= StatusWord_2;
 170         AX_reg(context) &= 0x1fff;
 171         StatusWord_2 = AX_reg(context);
 172         break;
 173
 174     case 9: /* clear emu control word and some other things */
 175         WIN87_ClearCtrlWord(context);
 176         break;
 177
 178     case 10: /* dunno. but looks like returning nr. of things on stack in AX */
 179         AX_reg(context) = 0;
 180         break;
 181
 182     case 11: /* just returns the installed flag in DX:AX */
 183         DX_reg(context) = 0;
 184         AX_reg(context) = Installed;
 185         break;
 186
 187     case 12: /* save AX in some internal state var */
 188         Inthandler02hVar = AX_reg(context);
 189         break;
 190
 191     default: /* error. Say that loud and clear */
 192         FIXME("unhandled switch %d\n",BX_reg(context));
 193         AX_reg(context) = DX_reg(context) = 0xFFFF;
 194         break;
 195     }
 196 }
 197
 198
 199 void WINAPI WIN87_WinEm87Info(struct Win87EmInfoStruct *pWIS,
 200                               int cbWin87EmInfoStruct)
 201 {
 202   FIXME("(%p,%d), stub !\n",pWIS,cbWin87EmInfoStruct);
 203 }
 204
 205 void WINAPI WIN87_WinEm87Restore(void *pWin87EmSaveArea,
 206                                  int cbWin87EmSaveArea)
 207 {
 208   FIXME("(%p,%d), stub !\n",
 209         pWin87EmSaveArea,cbWin87EmSaveArea);
 210 }
 211
 212 void WINAPI WIN87_WinEm87Save(void *pWin87EmSaveArea, int cbWin87EmSaveArea)
 213 {
 214   FIXME("(%p,%d), stub !\n",
 215         pWin87EmSaveArea,cbWin87EmSaveArea);
 216 }