| 1 | /*\r |
| 2 | * Dos/PC Emulator\r |
| 3 | * Copyright (C) 1991 Jim Hudgens\r |
| 4 | *\r |
| 5 | *\r |
| 6 | * The file is part of GDE.\r |
| 7 | *\r |
| 8 | * GDE is free software; you can redistribute it and/or modify\r |
| 9 | * it under the terms of the GNU General Public License as published by\r |
| 10 | * the Free Software Foundation; either version 1, or (at your option)\r |
| 11 | * any later version.\r |
| 12 | *\r |
| 13 | * GDE is distributed in the hope that it will be useful,\r |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of\r |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\r |
| 16 | * GNU General Public License for more details.\r |
| 17 | *\r |
| 18 | * You should have received a copy of the GNU General Public License\r |
| 19 | * along with GDE; see the file COPYING. If not, write to\r |
| 20 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.\r |
| 21 | *\r |
| 22 | */\r |
| 23 | \r |
| 24 | #include "altairz80_defs.h"\r |
| 25 | #include "i86.h"\r |
| 26 | \r |
| 27 | extern uint32 GetBYTEExtended(register uint32 Addr);\r |
| 28 | extern void PutBYTEExtended(register uint32 Addr, const register uint32 Value);\r |
| 29 | \r |
| 30 | /* $Log: i86_prim_ops.c,v $\r |
| 31 | * Revision 0.9 2003-01-10 23:33:10 jce\r |
| 32 | * fixed some more warnings under gcc -Wall\r |
| 33 | *\r |
| 34 | * Revision 0.8 1992/04/11 21:58:13 hudgens\r |
| 35 | * fixed some code causing warnings under gcc -Wall\r |
| 36 | *\r |
| 37 | * Revision 0.7 1991/07/30 02:04:34 hudgens\r |
| 38 | * added copyright.\r |
| 39 | *\r |
| 40 | * Revision 0.6 1991/07/21 16:50:37 hudgens\r |
| 41 | * fixed all flags in the bit shift and rotate instructions so that they\r |
| 42 | * finally agree.\r |
| 43 | * Also fixed the flags associated with IMUL and MUL instructions.\r |
| 44 | *\r |
| 45 | * Revision 0.5 1991/07/21 01:28:16 hudgens\r |
| 46 | * added support for aad and aam primitives.\r |
| 47 | *\r |
| 48 | * Revision 0.4 1991/07/20 22:26:25 hudgens\r |
| 49 | * fixed problem with sign extension in subroutine mem_access_word.\r |
| 50 | *\r |
| 51 | * Revision 0.3 1991/07/17 03:48:22 hudgens\r |
| 52 | * fixed bugs having to do with the setting of flags in the\r |
| 53 | * shift and rotate operations. Also, fixed sign extension problem\r |
| 54 | * with push_word and pop_word.\r |
| 55 | *\r |
| 56 | * Revision 0.2 1991/04/01 02:36:00 hudgens\r |
| 57 | * Fixed several nasty bugs dealing with flag setting in the subroutines\r |
| 58 | * sub_byte, sub_word, sbb_byte, sbb_word, and test_word. The results\r |
| 59 | * now agree with the PC on both of the testaopb and testaopw tests.\r |
| 60 | *\r |
| 61 | * Revision 0.1 1991/03/30 21:13:37 hudgens\r |
| 62 | * Initial checkin.\r |
| 63 | *\r |
| 64 | *\r |
| 65 | */\r |
| 66 | \r |
| 67 | /* [JCE] Stop gcc -Wall complaining */\r |
| 68 | void i86_intr_raise(PC_ENV *m, uint8 intrnum);\r |
| 69 | \r |
| 70 | /* the following table was generated using the following\r |
| 71 | code (running on an IBM AT, Turbo C++ 2.0), for all values of i\r |
| 72 | between 0 and 255. AL is loaded with i's value, and then the\r |
| 73 | operation "and al,al" sets the parity flag. The flags are pushed\r |
| 74 | onto the stack, and then popped back into AX. Then AX is\r |
| 75 | returned. So the value of each table entry represents the\r |
| 76 | parity of its index into the table. This results in a somewhat\r |
| 77 | faster mechanism for parity calculations than the straightforward\r |
| 78 | method.\r |
| 79 | andflags(i,res) int *res; {\r |
| 80 | int flags;\r |
| 81 | _AX = i; asm and al,al; asm pushf; *res = _AX;\r |
| 82 | asm pop ax; flags = _AX; return flags;\r |
| 83 | }\r |
| 84 | */\r |
| 85 | \r |
| 86 | char parity_tab[] = {\r |
| 87 | /*0*/ 1, /*1*/ 0, /*2*/ 0, /*3*/ 1,\r |
| 88 | /*4*/ 0, /*5*/ 1, /*6*/ 1, /*7*/ 0,\r |
| 89 | /*8*/ 0, /*9*/ 1, /*a*/ 1, /*b*/ 0,\r |
| 90 | /*c*/ 1, /*d*/ 0, /*e*/ 0, /*f*/ 1,\r |
| 91 | /*10*/ 0, /*11*/ 1, /*12*/ 1, /*13*/ 0,\r |
| 92 | /*14*/ 1, /*15*/ 0, /*16*/ 0, /*17*/ 1,\r |
| 93 | /*18*/ 1, /*19*/ 0, /*1a*/ 0, /*1b*/ 1,\r |
| 94 | /*1c*/ 0, /*1d*/ 1, /*1e*/ 1, /*1f*/ 0,\r |
| 95 | /*20*/ 0, /*21*/ 1, /*22*/ 1, /*23*/ 0,\r |
| 96 | /*24*/ 1, /*25*/ 0, /*26*/ 0, /*27*/ 1,\r |
| 97 | /*28*/ 1, /*29*/ 0, /*2a*/ 0, /*2b*/ 1,\r |
| 98 | /*2c*/ 0, /*2d*/ 1, /*2e*/ 1, /*2f*/ 0,\r |
| 99 | /*30*/ 1, /*31*/ 0, /*32*/ 0, /*33*/ 1,\r |
| 100 | /*34*/ 0, /*35*/ 1, /*36*/ 1, /*37*/ 0,\r |
| 101 | /*38*/ 0, /*39*/ 1, /*3a*/ 1, /*3b*/ 0,\r |
| 102 | /*3c*/ 1, /*3d*/ 0, /*3e*/ 0, /*3f*/ 1,\r |
| 103 | /*40*/ 0, /*41*/ 1, /*42*/ 1, /*43*/ 0,\r |
| 104 | /*44*/ 1, /*45*/ 0, /*46*/ 0, /*47*/ 1,\r |
| 105 | /*48*/ 1, /*49*/ 0, /*4a*/ 0, /*4b*/ 1,\r |
| 106 | /*4c*/ 0, /*4d*/ 1, /*4e*/ 1, /*4f*/ 0,\r |
| 107 | /*50*/ 1, /*51*/ 0, /*52*/ 0, /*53*/ 1,\r |
| 108 | /*54*/ 0, /*55*/ 1, /*56*/ 1, /*57*/ 0,\r |
| 109 | /*58*/ 0, /*59*/ 1, /*5a*/ 1, /*5b*/ 0,\r |
| 110 | /*5c*/ 1, /*5d*/ 0, /*5e*/ 0, /*5f*/ 1,\r |
| 111 | /*60*/ 1, /*61*/ 0, /*62*/ 0, /*63*/ 1,\r |
| 112 | /*64*/ 0, /*65*/ 1, /*66*/ 1, /*67*/ 0,\r |
| 113 | /*68*/ 0, /*69*/ 1, /*6a*/ 1, /*6b*/ 0,\r |
| 114 | /*6c*/ 1, /*6d*/ 0, /*6e*/ 0, /*6f*/ 1,\r |
| 115 | /*70*/ 0, /*71*/ 1, /*72*/ 1, /*73*/ 0,\r |
| 116 | /*74*/ 1, /*75*/ 0, /*76*/ 0, /*77*/ 1,\r |
| 117 | /*78*/ 1, /*79*/ 0, /*7a*/ 0, /*7b*/ 1,\r |
| 118 | /*7c*/ 0, /*7d*/ 1, /*7e*/ 1, /*7f*/ 0,\r |
| 119 | /*80*/ 0, /*81*/ 1, /*82*/ 1, /*83*/ 0,\r |
| 120 | /*84*/ 1, /*85*/ 0, /*86*/ 0, /*87*/ 1,\r |
| 121 | /*88*/ 1, /*89*/ 0, /*8a*/ 0, /*8b*/ 1,\r |
| 122 | /*8c*/ 0, /*8d*/ 1, /*8e*/ 1, /*8f*/ 0,\r |
| 123 | /*90*/ 1, /*91*/ 0, /*92*/ 0, /*93*/ 1,\r |
| 124 | /*94*/ 0, /*95*/ 1, /*96*/ 1, /*97*/ 0,\r |
| 125 | /*98*/ 0, /*99*/ 1, /*9a*/ 1, /*9b*/ 0,\r |
| 126 | /*9c*/ 1, /*9d*/ 0, /*9e*/ 0, /*9f*/ 1,\r |
| 127 | /*a0*/ 1, /*a1*/ 0, /*a2*/ 0, /*a3*/ 1,\r |
| 128 | /*a4*/ 0, /*a5*/ 1, /*a6*/ 1, /*a7*/ 0,\r |
| 129 | /*a8*/ 0, /*a9*/ 1, /*aa*/ 1, /*ab*/ 0,\r |
| 130 | /*ac*/ 1, /*ad*/ 0, /*ae*/ 0, /*af*/ 1,\r |
| 131 | /*b0*/ 0, /*b1*/ 1, /*b2*/ 1, /*b3*/ 0,\r |
| 132 | /*b4*/ 1, /*b5*/ 0, /*b6*/ 0, /*b7*/ 1,\r |
| 133 | /*b8*/ 1, /*b9*/ 0, /*ba*/ 0, /*bb*/ 1,\r |
| 134 | /*bc*/ 0, /*bd*/ 1, /*be*/ 1, /*bf*/ 0,\r |
| 135 | /*c0*/ 1, /*c1*/ 0, /*c2*/ 0, /*c3*/ 1,\r |
| 136 | /*c4*/ 0, /*c5*/ 1, /*c6*/ 1, /*c7*/ 0,\r |
| 137 | /*c8*/ 0, /*c9*/ 1, /*ca*/ 1, /*cb*/ 0,\r |
| 138 | /*cc*/ 1, /*cd*/ 0, /*ce*/ 0, /*cf*/ 1,\r |
| 139 | /*d0*/ 0, /*d1*/ 1, /*d2*/ 1, /*d3*/ 0,\r |
| 140 | /*d4*/ 1, /*d5*/ 0, /*d6*/ 0, /*d7*/ 1,\r |
| 141 | /*d8*/ 1, /*d9*/ 0, /*da*/ 0, /*db*/ 1,\r |
| 142 | /*dc*/ 0, /*dd*/ 1, /*de*/ 1, /*df*/ 0,\r |
| 143 | /*e0*/ 0, /*e1*/ 1, /*e2*/ 1, /*e3*/ 0,\r |
| 144 | /*e4*/ 1, /*e5*/ 0, /*e6*/ 0, /*e7*/ 1,\r |
| 145 | /*e8*/ 1, /*e9*/ 0, /*ea*/ 0, /*eb*/ 1,\r |
| 146 | /*ec*/ 0, /*ed*/ 1, /*ee*/ 1, /*ef*/ 0,\r |
| 147 | /*f0*/ 1, /*f1*/ 0, /*f2*/ 0, /*f3*/ 1,\r |
| 148 | /*f4*/ 0, /*f5*/ 1, /*f6*/ 1, /*f7*/ 0,\r |
| 149 | /*f8*/ 0, /*f9*/ 1, /*fa*/ 1, /*fb*/ 0,\r |
| 150 | /*fc*/ 1, /*fd*/ 0, /*fe*/ 0, /*ff*/ 1,\r |
| 151 | };\r |
| 152 | \r |
| 153 | char xor_0x3_tab[] = { 0, 1, 1, 0 };\r |
| 154 | \r |
| 155 | /* CARRY CHAIN CALCULATION.\r |
| 156 | This represents a somewhat expensive calculation which is\r |
| 157 | apparently required to emulate the setting of the OF and\r |
| 158 | AF flag. The latter is not so important, but the former is.\r |
| 159 | The overflow flag is the XOR of the top two bits of the\r |
| 160 | carry chain for an addition (similar for subtraction).\r |
| 161 | Since we do not want to simulate the addition in a bitwise\r |
| 162 | manner, we try to calculate the carry chain given the\r |
| 163 | two operands and the result.\r |
| 164 | \r |
| 165 | So, given the following table, which represents the\r |
| 166 | addition of two bits, we can derive a formula for\r |
| 167 | the carry chain.\r |
| 168 | \r |
| 169 | a b cin r cout\r |
| 170 | 0 0 0 0 0\r |
| 171 | 0 0 1 1 0\r |
| 172 | 0 1 0 1 0\r |
| 173 | 0 1 1 0 1\r |
| 174 | 1 0 0 1 0\r |
| 175 | 1 0 1 0 1\r |
| 176 | 1 1 0 0 1\r |
| 177 | 1 1 1 1 1\r |
| 178 | \r |
| 179 | Construction of table for cout:\r |
| 180 | \r |
| 181 | ab\r |
| 182 | r \ 00 01 11 10\r |
| 183 | |------------------\r |
| 184 | 0 | 0 1 1 1\r |
| 185 | 1 | 0 0 1 0\r |
| 186 | \r |
| 187 | By inspection, one gets: cc = ab + r'(a + b)\r |
| 188 | \r |
| 189 | That represents alot of operations, but NO CHOICE....\r |
| 190 | \r |
| 191 | BORROW CHAIN CALCULATION.\r |
| 192 | The following table represents the\r |
| 193 | subtraction of two bits, from which we can derive a formula for\r |
| 194 | the borrow chain.\r |
| 195 | \r |
| 196 | a b bin r bout\r |
| 197 | 0 0 0 0 0\r |
| 198 | 0 0 1 1 1\r |
| 199 | 0 1 0 1 1\r |
| 200 | 0 1 1 0 1\r |
| 201 | 1 0 0 1 0\r |
| 202 | 1 0 1 0 0\r |
| 203 | 1 1 0 0 0\r |
| 204 | 1 1 1 1 1\r |
| 205 | \r |
| 206 | Construction of table for cout:\r |
| 207 | \r |
| 208 | ab\r |
| 209 | r \ 00 01 11 10\r |
| 210 | |------------------\r |
| 211 | 0 | 0 1 0 0\r |
| 212 | 1 | 1 1 1 0\r |
| 213 | \r |
| 214 | By inspection, one gets: bc = a'b + r(a' + b)\r |
| 215 | \r |
| 216 | */\r |
| 217 | \r |
| 218 | uint8 aad_word(PC_ENV *m, uint16 d)\r |
| 219 | {\r |
| 220 | uint16 l;\r |
| 221 | uint8 hb,lb;\r |
| 222 | hb = (d>>8)&0xff;\r |
| 223 | lb = (d&0xff);\r |
| 224 | l = lb + 10 * hb;\r |
| 225 | CONDITIONAL_SET_FLAG(l & 0x80, m, F_SF);\r |
| 226 | CONDITIONAL_SET_FLAG(l == 0, m, F_ZF);\r |
| 227 | CONDITIONAL_SET_FLAG(parity_tab[l & 0xff], m, F_PF);\r |
| 228 | return (uint8) l;\r |
| 229 | }\r |
| 230 | \r |
| 231 | uint16 aam_word(PC_ENV *m, uint8 d)\r |
| 232 | {\r |
| 233 | uint16 h,l;\r |
| 234 | h = d / 10;\r |
| 235 | l = d % 10;\r |
| 236 | l |= (h<<8);\r |
| 237 | CONDITIONAL_SET_FLAG(l & 0x80, m, F_SF);\r |
| 238 | CONDITIONAL_SET_FLAG(l == 0, m, F_ZF);\r |
| 239 | CONDITIONAL_SET_FLAG(parity_tab[l & 0xff], m, F_PF);\r |
| 240 | return l;\r |
| 241 | }\r |
| 242 | \r |
| 243 | uint8 adc_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 244 | {\r |
| 245 | register uint16 res; /* all operands in native machine order */\r |
| 246 | register uint16 cc;\r |
| 247 | if (ACCESS_FLAG(m,F_CF) )\r |
| 248 | res = 1 + d + s;\r |
| 249 | else\r |
| 250 | res = d + s;\r |
| 251 | CONDITIONAL_SET_FLAG(res & 0x100, m, F_CF);\r |
| 252 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 253 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 254 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 255 | /* calculate the carry chain SEE NOTE AT TOP.*/\r |
| 256 | cc = (s & d) | ((~res) & (s | d));\r |
| 257 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(cc>>6)&0x3], m, F_OF);\r |
| 258 | CONDITIONAL_SET_FLAG(cc&0x8, m, F_AF);\r |
| 259 | return (uint8) res;\r |
| 260 | }\r |
| 261 | \r |
| 262 | uint16 adc_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 263 | {\r |
| 264 | register uint32 res; /* all operands in native machine order */\r |
| 265 | register uint32 cc;\r |
| 266 | if (ACCESS_FLAG(m,F_CF) )\r |
| 267 | res = 1 + d + s;\r |
| 268 | else\r |
| 269 | res = d + s;\r |
| 270 | /* set the carry flag to be bit 8 */\r |
| 271 | CONDITIONAL_SET_FLAG(res & 0x10000, m, F_CF);\r |
| 272 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 273 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 274 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 275 | /* calculate the carry chain SEE NOTE AT TOP.*/\r |
| 276 | cc = (s & d) | ((~res) & (s | d));\r |
| 277 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(cc>>14)&0x3], m, F_OF);\r |
| 278 | CONDITIONAL_SET_FLAG(cc&0x8, m, F_AF);\r |
| 279 | return res;\r |
| 280 | }\r |
| 281 | \r |
| 282 | /* Given flags=f, and bytes d (dest) and s (source)\r |
| 283 | perform the add and set the flags and the result back to\r |
| 284 | *d. USE NATIVE MACHINE ORDER...\r |
| 285 | */\r |
| 286 | uint8 add_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 287 | {\r |
| 288 | register uint16 res; /* all operands in native machine order */\r |
| 289 | register uint16 cc;\r |
| 290 | res = d + s;\r |
| 291 | /* set the carry flag to be bit 8 */\r |
| 292 | CONDITIONAL_SET_FLAG(res & 0x100, m, F_CF);\r |
| 293 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 294 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 295 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 296 | /* calculate the carry chain SEE NOTE AT TOP.*/\r |
| 297 | cc = (s & d) | ((~res) & (s | d));\r |
| 298 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(cc>>6)&0x3], m, F_OF);\r |
| 299 | CONDITIONAL_SET_FLAG(cc&0x8, m, F_AF);\r |
| 300 | return (uint8) res;\r |
| 301 | }\r |
| 302 | \r |
| 303 | /* Given flags=f, and bytes d (dest) and s (source)\r |
| 304 | perform the add and set the flags and the result back to\r |
| 305 | *d. USE NATIVE MACHINE ORDER...\r |
| 306 | */\r |
| 307 | uint16 add_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 308 | {\r |
| 309 | register uint32 res; /* all operands in native machine order */\r |
| 310 | register uint32 cc;\r |
| 311 | res = d + s;\r |
| 312 | /* set the carry flag to be bit 8 */\r |
| 313 | CONDITIONAL_SET_FLAG(res & 0x10000, m, F_CF);\r |
| 314 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 315 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 316 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 317 | /* calculate the carry chain SEE NOTE AT TOP.*/\r |
| 318 | cc = (s & d) | ((~res) & (s | d));\r |
| 319 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(cc>>14)&0x3], m, F_OF);\r |
| 320 | CONDITIONAL_SET_FLAG(cc&0x8, m, F_AF);\r |
| 321 | return res;\r |
| 322 | }\r |
| 323 | \r |
| 324 | /*\r |
| 325 | Flags m->R_FLG, dest *d, source *s, do a bitwise and of the\r |
| 326 | source and destination, and then store back to the\r |
| 327 | destination. Size=byte.\r |
| 328 | */\r |
| 329 | uint8 and_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 330 | {\r |
| 331 | register uint8 res; /* all operands in native machine order */\r |
| 332 | res = d & s;\r |
| 333 | /* set the flags */\r |
| 334 | CLEAR_FLAG(m, F_OF);\r |
| 335 | CLEAR_FLAG(m, F_CF);\r |
| 336 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 337 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 338 | CONDITIONAL_SET_FLAG(parity_tab[res], m, F_PF);\r |
| 339 | return res;\r |
| 340 | }\r |
| 341 | \r |
| 342 | /*\r |
| 343 | Flags m->R_FLG, dest *d, source *s, do a bitwise and of the\r |
| 344 | source and destination, and then store back to the\r |
| 345 | destination. Size=byte.\r |
| 346 | */\r |
| 347 | uint16 and_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 348 | {\r |
| 349 | register uint16 res; /* all operands in native machine order */\r |
| 350 | res = d & s;\r |
| 351 | /* set the flags */\r |
| 352 | CLEAR_FLAG(m, F_OF);\r |
| 353 | CLEAR_FLAG(m, F_CF);\r |
| 354 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 355 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 356 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 357 | return res;\r |
| 358 | }\r |
| 359 | \r |
| 360 | uint8 cmp_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 361 | {\r |
| 362 | register uint32 res; /* all operands in native machine order */\r |
| 363 | register uint32 bc;\r |
| 364 | res = d - s;\r |
| 365 | CLEAR_FLAG(m, F_CF);\r |
| 366 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 367 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 368 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 369 | /* calculate the borrow chain. See note at top */\r |
| 370 | bc= (res&(~d|s))|(~d&s);\r |
| 371 | CONDITIONAL_SET_FLAG(bc&0x80,m, F_CF);\r |
| 372 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>6)&0x3], m, F_OF);\r |
| 373 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 374 | return d; /* long story why this is needed. Look at opcode\r |
| 375 | 0x80 in ops.c, for an idea why this is necessary.*/\r |
| 376 | }\r |
| 377 | \r |
| 378 | uint16 cmp_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 379 | {\r |
| 380 | register uint32 res; /* all operands in native machine order */\r |
| 381 | register uint32 bc;\r |
| 382 | res = d - s;\r |
| 383 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 384 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 385 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 386 | /* calculate the borrow chain. See note at top */\r |
| 387 | bc= (res&(~d|s))|(~d&s);\r |
| 388 | CONDITIONAL_SET_FLAG(bc&0x8000,m, F_CF);\r |
| 389 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>14)&0x3], m, F_OF);\r |
| 390 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 391 | return d;\r |
| 392 | }\r |
| 393 | \r |
| 394 | uint8 dec_byte(PC_ENV *m, uint8 d)\r |
| 395 | {\r |
| 396 | register uint32 res; /* all operands in native machine order */\r |
| 397 | register uint32 bc;\r |
| 398 | res = d - 1;\r |
| 399 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 400 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 401 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 402 | /* calculate the borrow chain. See note at top */\r |
| 403 | /* based on sub_byte, uses s==1. */\r |
| 404 | bc= (res&(~d|1))|(~d&1);\r |
| 405 | /* carry flag unchanged */\r |
| 406 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>6)&0x3], m, F_OF);\r |
| 407 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 408 | return res;\r |
| 409 | }\r |
| 410 | \r |
| 411 | uint16 dec_word(PC_ENV *m, uint16 d)\r |
| 412 | {\r |
| 413 | register uint32 res; /* all operands in native machine order */\r |
| 414 | register uint32 bc;\r |
| 415 | res = d - 1;\r |
| 416 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 417 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 418 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 419 | /* calculate the borrow chain. See note at top */\r |
| 420 | /* based on the sub_byte routine, with s==1 */\r |
| 421 | bc= (res&(~d|1))|(~d&1);\r |
| 422 | /* carry flag unchanged */\r |
| 423 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>14)&0x3], m, F_OF);\r |
| 424 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 425 | return res;\r |
| 426 | }\r |
| 427 | \r |
| 428 | /* Given flags=f, and byte d (dest)\r |
| 429 | perform the inc and set the flags and the result back to\r |
| 430 | d. USE NATIVE MACHINE ORDER...\r |
| 431 | */\r |
| 432 | uint8 inc_byte(PC_ENV *m, uint8 d)\r |
| 433 | {\r |
| 434 | register uint32 res; /* all operands in native machine order */\r |
| 435 | register uint32 cc;\r |
| 436 | res = d + 1;\r |
| 437 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 438 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 439 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 440 | /* calculate the carry chain SEE NOTE AT TOP.*/\r |
| 441 | cc = ((1 & d) | (~res)) & (1 | d);\r |
| 442 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(cc>>6)&0x3], m, F_OF);\r |
| 443 | CONDITIONAL_SET_FLAG(cc&0x8, m, F_AF);\r |
| 444 | return res;\r |
| 445 | }\r |
| 446 | \r |
| 447 | /* Given flags=f, and byte d (dest)\r |
| 448 | perform the inc and set the flags and the result back to\r |
| 449 | *d. USE NATIVE MACHINE ORDER...\r |
| 450 | */\r |
| 451 | uint16 inc_word(PC_ENV *m, uint16 d)\r |
| 452 | {\r |
| 453 | register uint32 res; /* all operands in native machine order */\r |
| 454 | register uint32 cc;\r |
| 455 | res = d + 1;\r |
| 456 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 457 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 458 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 459 | /* calculate the carry chain SEE NOTE AT TOP.*/\r |
| 460 | cc = (1 & d) | ((~res) & (1 | d));\r |
| 461 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(cc>>14)&0x3], m, F_OF);\r |
| 462 | CONDITIONAL_SET_FLAG(cc&0x8, m, F_AF);\r |
| 463 | return res ;\r |
| 464 | }\r |
| 465 | \r |
| 466 | uint8 or_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 467 | {\r |
| 468 | register uint8 res; /* all operands in native machine order */\r |
| 469 | res = d | s;\r |
| 470 | CLEAR_FLAG(m, F_OF);\r |
| 471 | CLEAR_FLAG(m, F_CF);\r |
| 472 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 473 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 474 | CONDITIONAL_SET_FLAG(parity_tab[res], m, F_PF);\r |
| 475 | return res;\r |
| 476 | }\r |
| 477 | \r |
| 478 | uint16 or_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 479 | {\r |
| 480 | register uint16 res; /* all operands in native machine order */\r |
| 481 | res = d | s;\r |
| 482 | /* set the carry flag to be bit 8 */\r |
| 483 | CLEAR_FLAG(m, F_OF);\r |
| 484 | CLEAR_FLAG(m, F_CF);\r |
| 485 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 486 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 487 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 488 | return res;\r |
| 489 | }\r |
| 490 | \r |
| 491 | uint8 neg_byte(PC_ENV *m, uint8 s)\r |
| 492 | {\r |
| 493 | register uint8 res;\r |
| 494 | register uint8 bc;\r |
| 495 | CONDITIONAL_SET_FLAG(s!=0, m, F_CF);\r |
| 496 | res = -s;\r |
| 497 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 498 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 499 | CONDITIONAL_SET_FLAG(parity_tab[res], m, F_PF);\r |
| 500 | /* calculate the borrow chain --- modified such that d=0.\r |
| 501 | substitutiing d=0 into bc= res&(~d|s)|(~d&s);\r |
| 502 | (the one used for sub) and simplifying, since ~d=0xff...,\r |
| 503 | ~d|s == 0xffff..., and res&0xfff... == res. Similarly\r |
| 504 | ~d&s == s. So the simplified result is:*/\r |
| 505 | bc= res|s;\r |
| 506 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>6)&0x3], m, F_OF);\r |
| 507 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 508 | return res;\r |
| 509 | }\r |
| 510 | \r |
| 511 | uint16 neg_word(PC_ENV *m, uint16 s)\r |
| 512 | {\r |
| 513 | register uint16 res;\r |
| 514 | register uint16 bc;\r |
| 515 | CONDITIONAL_SET_FLAG(s!=0, m, F_CF);\r |
| 516 | res = -s;\r |
| 517 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 518 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 519 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 520 | /* calculate the borrow chain --- modified such that d=0.\r |
| 521 | substitutiing d=0 into bc= res&(~d|s)|(~d&s);\r |
| 522 | (the one used for sub) and simplifying, since ~d=0xff...,\r |
| 523 | ~d|s == 0xffff..., and res&0xfff... == res. Similarly\r |
| 524 | ~d&s == s. So the simplified result is:*/\r |
| 525 | bc= res|s;\r |
| 526 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>6)&0x3], m, F_OF);\r |
| 527 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 528 | return res;\r |
| 529 | }\r |
| 530 | \r |
| 531 | uint8 not_byte(PC_ENV *m, uint8 s)\r |
| 532 | {\r |
| 533 | return ~s;\r |
| 534 | }\r |
| 535 | \r |
| 536 | uint16 not_word(PC_ENV *m, uint16 s)\r |
| 537 | {\r |
| 538 | return ~s;\r |
| 539 | }\r |
| 540 | \r |
| 541 | /* access stuff from absolute location in memory.\r |
| 542 | no segment registers are involved.\r |
| 543 | */\r |
| 544 | uint16 mem_access_word(PC_ENV *m, int addr)\r |
| 545 | {\r |
| 546 | /* Load in two steps. Native byte order independent */\r |
| 547 | return GetBYTEExtended(addr) | (GetBYTEExtended(addr + 1) << 8);\r |
| 548 | }\r |
| 549 | \r |
| 550 | /* given the register_set r, and memory descriptor m,\r |
| 551 | and word w, push w onto the stack.\r |
| 552 | w ASSUMED IN NATIVE MACHINE ORDER. Doesn't matter in this case???\r |
| 553 | */\r |
| 554 | void push_word(PC_ENV *m, uint16 w)\r |
| 555 | {\r |
| 556 | m->R_SP --;\r |
| 557 | PutBYTEExtended((m->R_SS << 4) + m->R_SP, w >> 8);\r |
| 558 | m->R_SP --;\r |
| 559 | PutBYTEExtended((m->R_SS << 4) + m->R_SP, w & 0xff);\r |
| 560 | }\r |
| 561 | \r |
| 562 | /* given the memory descriptor m,\r |
| 563 | and word w, pop word from the stack.\r |
| 564 | */\r |
| 565 | uint16 pop_word(PC_ENV *m)\r |
| 566 | {\r |
| 567 | register uint16 res;\r |
| 568 | res = GetBYTEExtended((m->R_SS << 4) + m->R_SP);\r |
| 569 | m->R_SP++;\r |
| 570 | res |= GetBYTEExtended((m->R_SS << 4) + m->R_SP) << 8;\r |
| 571 | m->R_SP++;\r |
| 572 | return res;\r |
| 573 | }\r |
| 574 | \r |
| 575 | /*****************************************************************\r |
| 576 | BEGIN region consisting of bit shifts and rotates,\r |
| 577 | much of which may be wrong. Large hirsute factor.\r |
| 578 | *****************************************************************/\r |
| 579 | uint8 rcl_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 580 | {\r |
| 581 | register uint32 res, cnt, mask,cf;\r |
| 582 | /* s is the rotate distance. It varies from 0 - 8. */\r |
| 583 | /* have\r |
| 584 | CF B_7 B_6 B_5 B_4 B_3 B_2 B_1 B_0\r |
| 585 | want to rotate through the carry by "s" bits. We could\r |
| 586 | loop, but that's inefficient. So the width is 9,\r |
| 587 | and we split into three parts:\r |
| 588 | The new carry flag (was B_n)\r |
| 589 | the stuff in B_n-1 .. B_0\r |
| 590 | the stuff in B_7 .. B_n+1\r |
| 591 | The new rotate is done mod 9, and given this,\r |
| 592 | for a rotation of n bits (mod 9) the new carry flag is\r |
| 593 | then located n bits from the MSB. The low part is\r |
| 594 | then shifted up cnt bits, and the high part is or'd\r |
| 595 | in. Using CAPS for new values, and lowercase for the\r |
| 596 | original values, this can be expressed as:\r |
| 597 | IF n > 0\r |
| 598 | 1) CF <- b_(8-n)\r |
| 599 | 2) B_(7) .. B_(n) <- b_(8-(n+1)) .. b_0\r |
| 600 | 3) B_(n-1) <- cf\r |
| 601 | 4) B_(n-2) .. B_0 <- b_7 .. b_(8-(n-1))\r |
| 602 | I think this is correct.\r |
| 603 | */\r |
| 604 | res = d;\r |
| 605 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 606 | if ((cnt = s % 9)) /* not a typo, do nada if cnt==0 */\r |
| 607 | {\r |
| 608 | /* extract the new CARRY FLAG. */\r |
| 609 | /* CF <- b_(8-n) */\r |
| 610 | cf = (d >> (8-cnt)) & 0x1;\r |
| 611 | /* get the low stuff which rotated\r |
| 612 | into the range B_7 .. B_cnt */\r |
| 613 | /* B_(7) .. B_(n) <- b_(8-(n+1)) .. b_0 */\r |
| 614 | /* note that the right hand side done by the mask */\r |
| 615 | res = (d << cnt) & 0xff;\r |
| 616 | /* now the high stuff which rotated around\r |
| 617 | into the positions B_cnt-2 .. B_0 */\r |
| 618 | /* B_(n-2) .. B_0 <- b_7 .. b_(8-(n-1)) */\r |
| 619 | /* shift it downward, 7-(n-2) = 9-n positions.\r |
| 620 | and mask off the result before or'ing in.\r |
| 621 | */\r |
| 622 | mask = (1<<(cnt-1)) - 1;\r |
| 623 | res |= (d >> (9-cnt)) & mask;\r |
| 624 | /* if the carry flag was set, or it in. */\r |
| 625 | if (ACCESS_FLAG(m,F_CF)) /* carry flag is set */\r |
| 626 | {\r |
| 627 | /* B_(n-1) <- cf */\r |
| 628 | res |= 1 << (cnt-1);\r |
| 629 | }\r |
| 630 | /* set the new carry flag, based on the variable "cf" */\r |
| 631 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 632 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 633 | xor of CF and the most significant bit. Blecck. */\r |
| 634 | /* parenthesized this expression since it appears to\r |
| 635 | be causing OF to be misset */\r |
| 636 | CONDITIONAL_SET_FLAG(cnt==1&&\r |
| 637 | xor_0x3_tab[cf+((res>>6)&0x2)],\r |
| 638 | m, F_OF);\r |
| 639 | }\r |
| 640 | return res & 0xff;\r |
| 641 | }\r |
| 642 | \r |
| 643 | uint16 rcl_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 644 | {\r |
| 645 | register uint32 res, cnt, mask,cf;\r |
| 646 | /* see analysis above. */\r |
| 647 | /* width here is 16 bits + carry bit */\r |
| 648 | res = d;\r |
| 649 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 650 | if ((cnt = s % 17)) /* not a typo, do nada if cnt==0 */\r |
| 651 | {\r |
| 652 | /* extract the new CARRY FLAG. */\r |
| 653 | /* CF <- b_(16-n) */\r |
| 654 | cf = (d >> (16-cnt)) & 0x1;\r |
| 655 | /* get the low stuff which rotated\r |
| 656 | into the range B_15 .. B_cnt */\r |
| 657 | /* B_(15) .. B_(n) <- b_(16-(n+1)) .. b_0 */\r |
| 658 | /* note that the right hand side done by the mask */\r |
| 659 | res = (d << cnt) & 0xffff;\r |
| 660 | /* now the high stuff which rotated around\r |
| 661 | into the positions B_cnt-2 .. B_0 */\r |
| 662 | /* B_(n-2) .. B_0 <- b_15 .. b_(16-(n-1)) */\r |
| 663 | /* shift it downward, 15-(n-2) = 17-n positions.\r |
| 664 | and mask off the result before or'ing in.\r |
| 665 | */\r |
| 666 | mask = (1<<(cnt-1)) - 1;\r |
| 667 | res |= (d >> (17-cnt)) & mask;\r |
| 668 | /* if the carry flag was set, or it in. */\r |
| 669 | if (ACCESS_FLAG(m, F_CF)) /* carry flag is set */\r |
| 670 | {\r |
| 671 | /* B_(n-1) <- cf */\r |
| 672 | res |= 1 << (cnt-1);\r |
| 673 | }\r |
| 674 | /* set the new carry flag, based on the variable "cf" */\r |
| 675 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 676 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 677 | xor of CF and the most significant bit. Blecck.\r |
| 678 | Note that we're forming a 2 bit word here to index\r |
| 679 | into the table. The expression cf+(res>>14)&0x2\r |
| 680 | represents the two bit word b_15 CF.\r |
| 681 | */\r |
| 682 | /* parenthesized following expression... */\r |
| 683 | CONDITIONAL_SET_FLAG(cnt==1&&xor_0x3_tab[cf+((res>>14)&0x2)],\r |
| 684 | m, F_OF);\r |
| 685 | }\r |
| 686 | return res & 0xffff;\r |
| 687 | }\r |
| 688 | \r |
| 689 | uint8 rcr_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 690 | {\r |
| 691 | uint8 res, cnt;\r |
| 692 | uint8 mask, cf, ocf = 0;\r |
| 693 | /* rotate right through carry */\r |
| 694 | /*\r |
| 695 | s is the rotate distance. It varies from 0 - 8.\r |
| 696 | d is the byte object rotated.\r |
| 697 | have\r |
| 698 | CF B_7 B_6 B_5 B_4 B_3 B_2 B_1 B_0\r |
| 699 | The new rotate is done mod 9, and given this,\r |
| 700 | for a rotation of n bits (mod 9) the new carry flag is\r |
| 701 | then located n bits from the LSB. The low part is\r |
| 702 | then shifted up cnt bits, and the high part is or'd\r |
| 703 | in. Using CAPS for new values, and lowercase for the\r |
| 704 | original values, this can be expressed as:\r |
| 705 | IF n > 0\r |
| 706 | 1) CF <- b_(n-1)\r |
| 707 | 2) B_(8-(n+1)) .. B_(0) <- b_(7) .. b_(n)\r |
| 708 | 3) B_(8-n) <- cf\r |
| 709 | 4) B_(7) .. B_(8-(n-1)) <- b_(n-2) .. b_(0)\r |
| 710 | I think this is correct.\r |
| 711 | */\r |
| 712 | res = d;\r |
| 713 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 714 | if ((cnt = s % 9)) /* not a typo, do nada if cnt==0 */\r |
| 715 | {\r |
| 716 | /* extract the new CARRY FLAG. */\r |
| 717 | /* CF <- b_(n-1) */\r |
| 718 | if (cnt == 1)\r |
| 719 | {\r |
| 720 | cf = d & 0x1;\r |
| 721 | /* note hackery here. Access_flag(..) evaluates to either\r |
| 722 | 0 if flag not set\r |
| 723 | non-zero if flag is set.\r |
| 724 | doing access_flag(..) != 0 casts that into either\r |
| 725 | 0..1 in any representation of the flags register\r |
| 726 | (i.e. packed bit array or unpacked.)\r |
| 727 | */\r |
| 728 | ocf = ACCESS_FLAG(m,F_CF) != 0;\r |
| 729 | }\r |
| 730 | else\r |
| 731 | cf = (d >> (cnt-1)) & 0x1;\r |
| 732 | /* B_(8-(n+1)) .. B_(0) <- b_(7) .. b_n */\r |
| 733 | /* note that the right hand side done by the mask\r |
| 734 | This is effectively done by shifting the\r |
| 735 | object to the right. The result must be masked,\r |
| 736 | in case the object came in and was treated\r |
| 737 | as a negative number. Needed???*/\r |
| 738 | mask = (1<<(8-cnt))-1;\r |
| 739 | res = (d >> cnt) & mask;\r |
| 740 | /* now the high stuff which rotated around\r |
| 741 | into the positions B_cnt-2 .. B_0 */\r |
| 742 | /* B_(7) .. B_(8-(n-1)) <- b_(n-2) .. b_(0) */\r |
| 743 | /* shift it downward, 7-(n-2) = 9-n positions.\r |
| 744 | and mask off the result before or'ing in.\r |
| 745 | */\r |
| 746 | res |= (d << (9-cnt));\r |
| 747 | /* if the carry flag was set, or it in. */\r |
| 748 | if (ACCESS_FLAG(m,F_CF)) /* carry flag is set */\r |
| 749 | {\r |
| 750 | /* B_(8-n) <- cf */\r |
| 751 | res |= 1 << (8 - cnt);\r |
| 752 | }\r |
| 753 | /* set the new carry flag, based on the variable "cf" */\r |
| 754 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 755 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 756 | xor of CF and the most significant bit. Blecck. */\r |
| 757 | /* parenthesized... */\r |
| 758 | if (cnt == 1)\r |
| 759 | { /* [JCE] Explicit braces to stop gcc -Wall moaning */\r |
| 760 | CONDITIONAL_SET_FLAG(xor_0x3_tab[ocf+((d>>6)&0x2)],\r |
| 761 | m, F_OF);\r |
| 762 | }\r |
| 763 | }\r |
| 764 | return res;\r |
| 765 | }\r |
| 766 | \r |
| 767 | uint16 rcr_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 768 | {\r |
| 769 | uint16 res, cnt;\r |
| 770 | uint16 mask, cf, ocf = 0;\r |
| 771 | /* rotate right through carry */\r |
| 772 | /*\r |
| 773 | s is the rotate distance. It varies from 0 - 8.\r |
| 774 | d is the byte object rotated.\r |
| 775 | have\r |
| 776 | CF B_15 ... B_0\r |
| 777 | The new rotate is done mod 17, and given this,\r |
| 778 | for a rotation of n bits (mod 17) the new carry flag is\r |
| 779 | then located n bits from the LSB. The low part is\r |
| 780 | then shifted up cnt bits, and the high part is or'd\r |
| 781 | in. Using CAPS for new values, and lowercase for the\r |
| 782 | original values, this can be expressed as:\r |
| 783 | IF n > 0\r |
| 784 | 1) CF <- b_(n-1)\r |
| 785 | 2) B_(16-(n+1)) .. B_(0) <- b_(15) .. b_(n)\r |
| 786 | 3) B_(16-n) <- cf\r |
| 787 | 4) B_(15) .. B_(16-(n-1)) <- b_(n-2) .. b_(0)\r |
| 788 | I think this is correct.\r |
| 789 | */\r |
| 790 | res = d;\r |
| 791 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 792 | if ((cnt = s % 17)) /* not a typo, do nada if cnt==0 */\r |
| 793 | {\r |
| 794 | /* extract the new CARRY FLAG. */\r |
| 795 | /* CF <- b_(n-1) */\r |
| 796 | if (cnt==1)\r |
| 797 | {\r |
| 798 | cf = d & 0x1;\r |
| 799 | /* see note above on teh byte version */\r |
| 800 | ocf = ACCESS_FLAG(m,F_CF) != 0;\r |
| 801 | }\r |
| 802 | else\r |
| 803 | cf = (d >> (cnt-1)) & 0x1;\r |
| 804 | /* B_(16-(n+1)) .. B_(0) <- b_(15) .. b_n */\r |
| 805 | /* note that the right hand side done by the mask\r |
| 806 | This is effectively done by shifting the\r |
| 807 | object to the right. The result must be masked,\r |
| 808 | in case the object came in and was treated\r |
| 809 | as a negative number. Needed???*/\r |
| 810 | mask = (1<<(16-cnt))-1;\r |
| 811 | res = (d >> cnt) & mask;\r |
| 812 | /* now the high stuff which rotated around\r |
| 813 | into the positions B_cnt-2 .. B_0 */\r |
| 814 | /* B_(15) .. B_(16-(n-1)) <- b_(n-2) .. b_(0) */\r |
| 815 | /* shift it downward, 15-(n-2) = 17-n positions.\r |
| 816 | and mask off the result before or'ing in.\r |
| 817 | */\r |
| 818 | res |= (d << (17-cnt));\r |
| 819 | /* if the carry flag was set, or it in. */\r |
| 820 | if (ACCESS_FLAG(m,F_CF)) /* carry flag is set */\r |
| 821 | {\r |
| 822 | /* B_(16-n) <- cf */\r |
| 823 | res |= 1 << (16 - cnt);\r |
| 824 | }\r |
| 825 | /* set the new carry flag, based on the variable "cf" */\r |
| 826 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 827 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 828 | xor of CF and the most significant bit. Blecck. */\r |
| 829 | if (cnt==1)\r |
| 830 | { /* [JCE] Explicit braces to stop gcc -Wall moaning */\r |
| 831 | CONDITIONAL_SET_FLAG(xor_0x3_tab[ocf+((d>>14)&0x2)],\r |
| 832 | m, F_OF);\r |
| 833 | }\r |
| 834 | }\r |
| 835 | return res;\r |
| 836 | }\r |
| 837 | \r |
| 838 | uint8 rol_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 839 | {\r |
| 840 | register uint32 res, cnt, mask;\r |
| 841 | /* rotate left */\r |
| 842 | /*\r |
| 843 | s is the rotate distance. It varies from 0 - 8.\r |
| 844 | d is the byte object rotated.\r |
| 845 | have\r |
| 846 | CF B_7 ... B_0\r |
| 847 | The new rotate is done mod 8.\r |
| 848 | Much simpler than the "rcl" or "rcr" operations.\r |
| 849 | IF n > 0\r |
| 850 | 1) B_(7) .. B_(n) <- b_(8-(n+1)) .. b_(0)\r |
| 851 | 2) B_(n-1) .. B_(0) <- b_(7) .. b_(8-n)\r |
| 852 | I think this is correct.\r |
| 853 | */\r |
| 854 | res =d;\r |
| 855 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 856 | if ((cnt = s % 8)) /* not a typo, do nada if cnt==0 */\r |
| 857 | {\r |
| 858 | /* B_(7) .. B_(n) <- b_(8-(n+1)) .. b_(0) */\r |
| 859 | res = (d << cnt);\r |
| 860 | /* B_(n-1) .. B_(0) <- b_(7) .. b_(8-n) */\r |
| 861 | mask = (1 << cnt) - 1;\r |
| 862 | res |= (d >> (8-cnt)) & mask;\r |
| 863 | /* set the new carry flag, Note that it is the low order\r |
| 864 | bit of the result!!! */\r |
| 865 | CONDITIONAL_SET_FLAG(res&0x1, m, F_CF);\r |
| 866 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 867 | xor of CF and the most significant bit. Blecck. */\r |
| 868 | CONDITIONAL_SET_FLAG(cnt==1 &&\r |
| 869 | xor_0x3_tab[(res&0x1)+((res>>6)&0x2)],\r |
| 870 | m, F_OF);\r |
| 871 | }\r |
| 872 | return res&0xff;\r |
| 873 | }\r |
| 874 | \r |
| 875 | uint16 rol_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 876 | {\r |
| 877 | register uint32 res, cnt, mask;\r |
| 878 | /* rotate left */\r |
| 879 | /*\r |
| 880 | s is the rotate distance. It varies from 0 - 8.\r |
| 881 | d is the byte object rotated.\r |
| 882 | have\r |
| 883 | CF B_15 ... B_0\r |
| 884 | The new rotate is done mod 8.\r |
| 885 | Much simpler than the "rcl" or "rcr" operations.\r |
| 886 | IF n > 0\r |
| 887 | 1) B_(15) .. B_(n) <- b_(16-(n+1)) .. b_(0)\r |
| 888 | 2) B_(n-1) .. B_(0) <- b_(16) .. b_(16-n)\r |
| 889 | I think this is correct.\r |
| 890 | */\r |
| 891 | res = d;\r |
| 892 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 893 | if ((cnt = s % 16)) /* not a typo, do nada if cnt==0 */\r |
| 894 | {\r |
| 895 | /* B_(16) .. B_(n) <- b_(16-(n+1)) .. b_(0) */\r |
| 896 | res = (d << cnt);\r |
| 897 | /* B_(n-1) .. B_(0) <- b_(15) .. b_(16-n) */\r |
| 898 | mask = (1 << cnt) - 1;\r |
| 899 | res |= (d >> (16-cnt)) & mask;\r |
| 900 | /* set the new carry flag, Note that it is the low order\r |
| 901 | bit of the result!!! */\r |
| 902 | CONDITIONAL_SET_FLAG(res&0x1, m, F_CF);\r |
| 903 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 904 | xor of CF and the most significant bit. Blecck. */\r |
| 905 | CONDITIONAL_SET_FLAG(cnt==1 &&\r |
| 906 | xor_0x3_tab[(res&0x1)+((res>>14)&0x2)],\r |
| 907 | m, F_OF);\r |
| 908 | }\r |
| 909 | return res&0xffff;\r |
| 910 | }\r |
| 911 | \r |
| 912 | uint8 ror_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 913 | {\r |
| 914 | register uint32 res, cnt, mask;\r |
| 915 | /* rotate right */\r |
| 916 | /*\r |
| 917 | s is the rotate distance. It varies from 0 - 8.\r |
| 918 | d is the byte object rotated.\r |
| 919 | have\r |
| 920 | B_7 ... B_0\r |
| 921 | The rotate is done mod 8.\r |
| 922 | IF n > 0\r |
| 923 | 1) B_(8-(n+1)) .. B_(0) <- b_(7) .. b_(n)\r |
| 924 | 2) B_(7) .. B_(8-n) <- b_(n-1) .. b_(0)\r |
| 925 | */\r |
| 926 | res = d;\r |
| 927 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 928 | if ((cnt = s % 8)) /* not a typo, do nada if cnt==0 */\r |
| 929 | {\r |
| 930 | /* B_(7) .. B_(8-n) <- b_(n-1) .. b_(0)*/\r |
| 931 | res = (d << (8-cnt));\r |
| 932 | /* B_(8-(n+1)) .. B_(0) <- b_(7) .. b_(n) */\r |
| 933 | mask = (1 << (8-cnt)) - 1;\r |
| 934 | res |= (d >> (cnt)) & mask;\r |
| 935 | /* set the new carry flag, Note that it is the low order\r |
| 936 | bit of the result!!! */\r |
| 937 | CONDITIONAL_SET_FLAG(res&0x80, m, F_CF);\r |
| 938 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 939 | xor of the two most significant bits. Blecck. */\r |
| 940 | CONDITIONAL_SET_FLAG(cnt==1 &&\r |
| 941 | xor_0x3_tab[(res>>6)&0x3],\r |
| 942 | m, F_OF);\r |
| 943 | }\r |
| 944 | return res&0xff;\r |
| 945 | }\r |
| 946 | \r |
| 947 | uint16 ror_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 948 | {\r |
| 949 | register uint32 res, cnt, mask;\r |
| 950 | /* rotate right */\r |
| 951 | /*\r |
| 952 | s is the rotate distance. It varies from 0 - 8.\r |
| 953 | d is the byte object rotated.\r |
| 954 | have\r |
| 955 | B_15 ... B_0\r |
| 956 | The rotate is done mod 16.\r |
| 957 | IF n > 0\r |
| 958 | 1) B_(16-(n+1)) .. B_(0) <- b_(15) .. b_(n)\r |
| 959 | 2) B_(15) .. B_(16-n) <- b_(n-1) .. b_(0)\r |
| 960 | I think this is correct.\r |
| 961 | */\r |
| 962 | res =d ;\r |
| 963 | /* [JCE] Extra brackets to stop gcc -Wall moaning */\r |
| 964 | if ((cnt = s % 16)) /* not a typo, do nada if cnt==0 */\r |
| 965 | {\r |
| 966 | /* B_(15) .. B_(16-n) <- b_(n-1) .. b_(0)*/\r |
| 967 | res = (d << (16-cnt));\r |
| 968 | /* B_(16-(n+1)) .. B_(0) <- b_(15) .. b_(n) */\r |
| 969 | mask = (1 << (16-cnt)) - 1;\r |
| 970 | res |= (d >> (cnt)) & mask;\r |
| 971 | /* set the new carry flag, Note that it is the low order\r |
| 972 | bit of the result!!! */\r |
| 973 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_CF);\r |
| 974 | /* OVERFLOW is set *IFF* cnt==1, then it is the\r |
| 975 | xor of CF and the most significant bit. Blecck. */\r |
| 976 | CONDITIONAL_SET_FLAG(cnt==1 &&\r |
| 977 | xor_0x3_tab[(res>>14)&0x3],\r |
| 978 | m, F_OF);\r |
| 979 | }\r |
| 980 | return res & 0xffff;\r |
| 981 | }\r |
| 982 | \r |
| 983 | uint8 shl_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 984 | {\r |
| 985 | uint32 cnt,res,cf;\r |
| 986 | if (s < 8)\r |
| 987 | {\r |
| 988 | cnt = s % 8;\r |
| 989 | /* last bit shifted out goes into carry flag */\r |
| 990 | if (cnt>0)\r |
| 991 | {\r |
| 992 | res = d << cnt;\r |
| 993 | cf = d & (1<<(8-cnt));\r |
| 994 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 995 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 996 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 997 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 998 | }\r |
| 999 | else\r |
| 1000 | {\r |
| 1001 | res = (uint8)d;\r |
| 1002 | }\r |
| 1003 | if (cnt == 1)\r |
| 1004 | {\r |
| 1005 | /* Needs simplification. */\r |
| 1006 | CONDITIONAL_SET_FLAG(\r |
| 1007 | (((res&0x80)==0x80) ^\r |
| 1008 | (ACCESS_FLAG(m,F_CF) != 0)) ,\r |
| 1009 | /* was (m->R_FLG&F_CF)==F_CF)), */\r |
| 1010 | m, F_OF);\r |
| 1011 | }\r |
| 1012 | else\r |
| 1013 | {\r |
| 1014 | CLEAR_FLAG(m,F_OF);\r |
| 1015 | }\r |
| 1016 | }\r |
| 1017 | else\r |
| 1018 | {\r |
| 1019 | res = 0;\r |
| 1020 | CLEAR_FLAG(m,F_CF);\r |
| 1021 | CLEAR_FLAG(m,F_OF);\r |
| 1022 | CLEAR_FLAG(m,F_SF);\r |
| 1023 | CLEAR_FLAG(m,F_PF);\r |
| 1024 | SET_FLAG(m,F_ZF);\r |
| 1025 | }\r |
| 1026 | return res&0xff;\r |
| 1027 | }\r |
| 1028 | \r |
| 1029 | uint16 shl_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1030 | {\r |
| 1031 | uint32 cnt,res,cf;\r |
| 1032 | if (s < 16)\r |
| 1033 | {\r |
| 1034 | cnt = s % 16;\r |
| 1035 | if (cnt > 0)\r |
| 1036 | {\r |
| 1037 | res = d << cnt;\r |
| 1038 | /* last bit shifted out goes into carry flag */\r |
| 1039 | cf = d & (1<<(16-cnt));\r |
| 1040 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 1041 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 1042 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 1043 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1044 | }\r |
| 1045 | else\r |
| 1046 | {\r |
| 1047 | res = (uint16)d;\r |
| 1048 | }\r |
| 1049 | if (cnt == 1)\r |
| 1050 | {\r |
| 1051 | /* Needs simplification. */\r |
| 1052 | CONDITIONAL_SET_FLAG(\r |
| 1053 | (((res&0x8000)==0x8000) ^\r |
| 1054 | (ACCESS_FLAG(m,F_CF) != 0)),\r |
| 1055 | /*((m&F_CF)==F_CF)),*/\r |
| 1056 | m, F_OF);\r |
| 1057 | }\r |
| 1058 | else\r |
| 1059 | {\r |
| 1060 | CLEAR_FLAG(m,F_OF);\r |
| 1061 | }\r |
| 1062 | }\r |
| 1063 | else\r |
| 1064 | {\r |
| 1065 | res = 0;\r |
| 1066 | CLEAR_FLAG(m,F_CF);\r |
| 1067 | CLEAR_FLAG(m,F_OF);\r |
| 1068 | SET_FLAG(m,F_ZF);\r |
| 1069 | CLEAR_FLAG(m,F_SF);\r |
| 1070 | CLEAR_FLAG(m,F_PF);\r |
| 1071 | }\r |
| 1072 | return res&0xffff;\r |
| 1073 | }\r |
| 1074 | \r |
| 1075 | uint8 shr_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 1076 | {\r |
| 1077 | uint32 cnt,res,cf,mask;\r |
| 1078 | if (s < 8)\r |
| 1079 | {\r |
| 1080 | cnt = s % 8;\r |
| 1081 | if (cnt > 0)\r |
| 1082 | {\r |
| 1083 | mask = (1<<(8-cnt))-1;\r |
| 1084 | cf = d & (1<<(cnt-1));\r |
| 1085 | res = (d >> cnt) & mask;\r |
| 1086 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 1087 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 1088 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 1089 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1090 | }\r |
| 1091 | else\r |
| 1092 | {\r |
| 1093 | res = (uint8) d;\r |
| 1094 | }\r |
| 1095 | if (cnt == 1)\r |
| 1096 | {\r |
| 1097 | CONDITIONAL_SET_FLAG(\r |
| 1098 | xor_0x3_tab[(res>>6)&0x3], m, F_OF);\r |
| 1099 | }\r |
| 1100 | else\r |
| 1101 | {\r |
| 1102 | CLEAR_FLAG(m,F_OF);\r |
| 1103 | }\r |
| 1104 | }\r |
| 1105 | else\r |
| 1106 | {\r |
| 1107 | res = 0;\r |
| 1108 | CLEAR_FLAG(m,F_CF);\r |
| 1109 | CLEAR_FLAG(m,F_OF);\r |
| 1110 | SET_FLAG(m,F_ZF);\r |
| 1111 | CLEAR_FLAG(m,F_SF);\r |
| 1112 | CLEAR_FLAG(m,F_PF);\r |
| 1113 | }\r |
| 1114 | return res&0xff;\r |
| 1115 | }\r |
| 1116 | \r |
| 1117 | uint16 shr_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1118 | {\r |
| 1119 | uint32 cnt,res,cf,mask;\r |
| 1120 | res = d;\r |
| 1121 | if (s < 16)\r |
| 1122 | {\r |
| 1123 | cnt = s % 16;\r |
| 1124 | if (cnt > 0)\r |
| 1125 | {\r |
| 1126 | mask = (1<<(16-cnt))-1;\r |
| 1127 | cf = d & (1<<(cnt-1));\r |
| 1128 | res = (d >> cnt) & mask;\r |
| 1129 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 1130 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 1131 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 1132 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1133 | }\r |
| 1134 | else\r |
| 1135 | {\r |
| 1136 | res = d;\r |
| 1137 | }\r |
| 1138 | if (cnt == 1)\r |
| 1139 | {\r |
| 1140 | CONDITIONAL_SET_FLAG(\r |
| 1141 | xor_0x3_tab[(res>>14)&0x3], m, F_OF);\r |
| 1142 | }\r |
| 1143 | else\r |
| 1144 | {\r |
| 1145 | CLEAR_FLAG(m,F_OF);\r |
| 1146 | }\r |
| 1147 | }\r |
| 1148 | else\r |
| 1149 | {\r |
| 1150 | res = 0;\r |
| 1151 | CLEAR_FLAG(m,F_CF);\r |
| 1152 | CLEAR_FLAG(m,F_OF);\r |
| 1153 | SET_FLAG(m,F_ZF);\r |
| 1154 | CLEAR_FLAG(m,F_SF);\r |
| 1155 | CLEAR_FLAG(m,F_PF);\r |
| 1156 | }\r |
| 1157 | return res&0xffff;\r |
| 1158 | }\r |
| 1159 | \r |
| 1160 | /* XXXX ??? flags may be wrong??? */\r |
| 1161 | uint8 sar_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 1162 | {\r |
| 1163 | uint32 cnt,res,cf,mask,sf;\r |
| 1164 | res = d;\r |
| 1165 | sf = d & 0x80;\r |
| 1166 | cnt = s % 8;\r |
| 1167 | if(cnt > 0 && cnt < 8)\r |
| 1168 | {\r |
| 1169 | mask = (1<<(8-cnt))-1;\r |
| 1170 | cf = d & (1<<(cnt-1));\r |
| 1171 | res = (d >> cnt) & mask;\r |
| 1172 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 1173 | if (sf)\r |
| 1174 | {\r |
| 1175 | res |= ~mask;\r |
| 1176 | }\r |
| 1177 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 1178 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1179 | CONDITIONAL_SET_FLAG(res & 0x80, m, F_SF);\r |
| 1180 | }\r |
| 1181 | else if (cnt >= 8)\r |
| 1182 | {\r |
| 1183 | if (sf)\r |
| 1184 | {\r |
| 1185 | res = 0xff;\r |
| 1186 | SET_FLAG(m,F_CF);\r |
| 1187 | CLEAR_FLAG(m,F_ZF);\r |
| 1188 | SET_FLAG(m, F_SF);\r |
| 1189 | SET_FLAG(m, F_PF);\r |
| 1190 | }\r |
| 1191 | else\r |
| 1192 | {\r |
| 1193 | res = 0;\r |
| 1194 | CLEAR_FLAG(m,F_CF);\r |
| 1195 | SET_FLAG(m,F_ZF);\r |
| 1196 | CLEAR_FLAG(m, F_SF);\r |
| 1197 | CLEAR_FLAG(m, F_PF);\r |
| 1198 | }\r |
| 1199 | }\r |
| 1200 | return res&0xff;\r |
| 1201 | }\r |
| 1202 | \r |
| 1203 | uint16 sar_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1204 | {\r |
| 1205 | uint32 cnt, res, cf, mask, sf;\r |
| 1206 | sf = d & 0x8000;\r |
| 1207 | cnt = s % 16;\r |
| 1208 | res = d;\r |
| 1209 | if (cnt > 0 && cnt < 16)\r |
| 1210 | {\r |
| 1211 | mask = (1<<(16-cnt))-1;\r |
| 1212 | cf = d & (1<<(cnt-1));\r |
| 1213 | res = (d >> cnt) & mask;\r |
| 1214 | CONDITIONAL_SET_FLAG(cf, m, F_CF);\r |
| 1215 | if (sf)\r |
| 1216 | {\r |
| 1217 | res |= ~mask;\r |
| 1218 | }\r |
| 1219 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 1220 | CONDITIONAL_SET_FLAG(res & 0x8000, m, F_SF);\r |
| 1221 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1222 | }\r |
| 1223 | else if (cnt >= 16)\r |
| 1224 | {\r |
| 1225 | if (sf)\r |
| 1226 | {\r |
| 1227 | res = 0xffff;\r |
| 1228 | SET_FLAG(m,F_CF);\r |
| 1229 | CLEAR_FLAG(m,F_ZF);\r |
| 1230 | SET_FLAG(m, F_SF);\r |
| 1231 | SET_FLAG(m, F_PF);\r |
| 1232 | }\r |
| 1233 | else\r |
| 1234 | {\r |
| 1235 | res = 0;\r |
| 1236 | CLEAR_FLAG(m,F_CF);\r |
| 1237 | SET_FLAG(m,F_ZF);\r |
| 1238 | CLEAR_FLAG(m, F_SF);\r |
| 1239 | CLEAR_FLAG(m, F_PF);\r |
| 1240 | }\r |
| 1241 | }\r |
| 1242 | return res&0xffff;\r |
| 1243 | }\r |
| 1244 | \r |
| 1245 | uint8 sbb_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 1246 | {\r |
| 1247 | register uint32 res; /* all operands in native machine order */\r |
| 1248 | register uint32 bc;\r |
| 1249 | if (ACCESS_FLAG(m,F_CF) )\r |
| 1250 | res = d - s - 1;\r |
| 1251 | else\r |
| 1252 | res = d - s;\r |
| 1253 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 1254 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 1255 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1256 | /* calculate the borrow chain. See note at top */\r |
| 1257 | bc= (res&(~d|s))|(~d&s);\r |
| 1258 | CONDITIONAL_SET_FLAG(bc&0x80,m, F_CF);\r |
| 1259 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>6)&0x3], m, F_OF);\r |
| 1260 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 1261 | return res & 0xff;\r |
| 1262 | }\r |
| 1263 | \r |
| 1264 | uint16 sbb_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1265 | {\r |
| 1266 | register uint32 res; /* all operands in native machine order */\r |
| 1267 | register uint32 bc;\r |
| 1268 | if (ACCESS_FLAG(m,F_CF))\r |
| 1269 | res = d - s - 1;\r |
| 1270 | else\r |
| 1271 | res = d - s;\r |
| 1272 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 1273 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 1274 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1275 | /* calculate the borrow chain. See note at top */\r |
| 1276 | bc= (res&(~d|s))|(~d&s);\r |
| 1277 | CONDITIONAL_SET_FLAG(bc&0x8000,m, F_CF);\r |
| 1278 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>14)&0x3], m, F_OF);\r |
| 1279 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 1280 | return res & 0xffff;\r |
| 1281 | }\r |
| 1282 | \r |
| 1283 | uint8 sub_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 1284 | {\r |
| 1285 | register uint32 res; /* all operands in native machine order */\r |
| 1286 | register uint32 bc;\r |
| 1287 | res = d - s;\r |
| 1288 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 1289 | CONDITIONAL_SET_FLAG((res&0xff)==0, m, F_ZF);\r |
| 1290 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1291 | /* calculate the borrow chain. See note at top */\r |
| 1292 | bc= (res&(~d|s))|(~d&s);\r |
| 1293 | CONDITIONAL_SET_FLAG(bc&0x80,m, F_CF);\r |
| 1294 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>6)&0x3], m, F_OF);\r |
| 1295 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 1296 | return res & 0xff;\r |
| 1297 | }\r |
| 1298 | \r |
| 1299 | uint16 sub_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1300 | {\r |
| 1301 | register uint32 res; /* all operands in native machine order */\r |
| 1302 | register uint32 bc;\r |
| 1303 | res = d - s;\r |
| 1304 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 1305 | CONDITIONAL_SET_FLAG((res&0xffff)==0, m, F_ZF);\r |
| 1306 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1307 | /* calculate the borrow chain. See note at top */\r |
| 1308 | bc= (res&(~d|s))|(~d&s);\r |
| 1309 | CONDITIONAL_SET_FLAG(bc&0x8000,m, F_CF);\r |
| 1310 | CONDITIONAL_SET_FLAG(xor_0x3_tab[(bc>>14)&0x3], m, F_OF);\r |
| 1311 | CONDITIONAL_SET_FLAG(bc&0x8, m, F_AF);\r |
| 1312 | return res & 0xffff;\r |
| 1313 | }\r |
| 1314 | \r |
| 1315 | void test_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 1316 | {\r |
| 1317 | register uint32 res; /* all operands in native machine order */\r |
| 1318 | res = d & s;\r |
| 1319 | CLEAR_FLAG(m, F_OF);\r |
| 1320 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 1321 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 1322 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1323 | /* AF == dont care*/\r |
| 1324 | CLEAR_FLAG(m, F_CF);\r |
| 1325 | }\r |
| 1326 | \r |
| 1327 | void test_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1328 | {\r |
| 1329 | register uint32 res; /* all operands in native machine order */\r |
| 1330 | res = d & s;\r |
| 1331 | CLEAR_FLAG(m, F_OF);\r |
| 1332 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 1333 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 1334 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1335 | /* AF == dont care*/\r |
| 1336 | CLEAR_FLAG(m, F_CF);\r |
| 1337 | }\r |
| 1338 | \r |
| 1339 | uint8 xor_byte(PC_ENV *m, uint8 d, uint8 s)\r |
| 1340 | {\r |
| 1341 | register uint8 res; /* all operands in native machine order */\r |
| 1342 | res = d ^ s;\r |
| 1343 | CLEAR_FLAG(m, F_OF);\r |
| 1344 | CONDITIONAL_SET_FLAG(res&0x80, m, F_SF);\r |
| 1345 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 1346 | CONDITIONAL_SET_FLAG(parity_tab[res], m, F_PF);\r |
| 1347 | CLEAR_FLAG(m, F_CF);\r |
| 1348 | return res;\r |
| 1349 | }\r |
| 1350 | \r |
| 1351 | uint16 xor_word(PC_ENV *m, uint16 d, uint16 s)\r |
| 1352 | {\r |
| 1353 | register uint16 res; /* all operands in native machine order */\r |
| 1354 | res = d ^ s;\r |
| 1355 | /* set the carry flag to be bit 8 */\r |
| 1356 | CLEAR_FLAG(m, F_OF);\r |
| 1357 | CONDITIONAL_SET_FLAG(res&0x8000, m, F_SF);\r |
| 1358 | CONDITIONAL_SET_FLAG(res==0, m, F_ZF);\r |
| 1359 | CONDITIONAL_SET_FLAG(parity_tab[res&0xff], m, F_PF);\r |
| 1360 | CLEAR_FLAG(m, F_CF);\r |
| 1361 | return res;\r |
| 1362 | }\r |
| 1363 | \r |
| 1364 | void imul_byte(PC_ENV *m, uint8 s)\r |
| 1365 | {\r |
| 1366 | int16 res = (int8)m->R_AL * (int8)s;\r |
| 1367 | m->R_AX = res;\r |
| 1368 | /* Undef --- Can't hurt */\r |
| 1369 | CONDITIONAL_SET_FLAG(res&0x8000,m,F_SF);\r |
| 1370 | CONDITIONAL_SET_FLAG(res==0,m,F_ZF);\r |
| 1371 | if (m->R_AH == 0 || m->R_AH == 0xff)\r |
| 1372 | {\r |
| 1373 | CLEAR_FLAG(m, F_CF);\r |
| 1374 | CLEAR_FLAG(m, F_OF);\r |
| 1375 | }\r |
| 1376 | else\r |
| 1377 | {\r |
| 1378 | SET_FLAG(m, F_CF);\r |
| 1379 | SET_FLAG(m, F_OF);\r |
| 1380 | }\r |
| 1381 | }\r |
| 1382 | \r |
| 1383 | void imul_word(PC_ENV *m, uint16 s)\r |
| 1384 | {\r |
| 1385 | int32 res = (int16)m->R_AX * (int16)s;\r |
| 1386 | m->R_AX = res & 0xffff;\r |
| 1387 | m->R_DX = (res >> 16) & 0xffff;\r |
| 1388 | /* Undef --- Can't hurt */\r |
| 1389 | CONDITIONAL_SET_FLAG(res&0x80000000,m,F_SF);\r |
| 1390 | CONDITIONAL_SET_FLAG(res==0,m,F_ZF);\r |
| 1391 | if (m->R_DX == 0 || m->R_DX == 0xffff)\r |
| 1392 | {\r |
| 1393 | CLEAR_FLAG(m, F_CF);\r |
| 1394 | CLEAR_FLAG(m, F_OF);\r |
| 1395 | }\r |
| 1396 | else\r |
| 1397 | {\r |
| 1398 | SET_FLAG(m, F_CF);\r |
| 1399 | SET_FLAG(m, F_OF);\r |
| 1400 | }\r |
| 1401 | }\r |
| 1402 | \r |
| 1403 | void mul_byte(PC_ENV *m, uint8 s)\r |
| 1404 | {\r |
| 1405 | uint16 res = m->R_AL * s;\r |
| 1406 | m->R_AX = res;\r |
| 1407 | /* Undef --- Can't hurt */\r |
| 1408 | CLEAR_FLAG(m,F_SF);\r |
| 1409 | CONDITIONAL_SET_FLAG(res==0,m,F_ZF);\r |
| 1410 | if (m->R_AH == 0)\r |
| 1411 | {\r |
| 1412 | CLEAR_FLAG(m, F_CF);\r |
| 1413 | CLEAR_FLAG(m, F_OF);\r |
| 1414 | }\r |
| 1415 | else\r |
| 1416 | {\r |
| 1417 | SET_FLAG(m, F_CF);\r |
| 1418 | SET_FLAG(m, F_OF);\r |
| 1419 | }\r |
| 1420 | }\r |
| 1421 | \r |
| 1422 | void mul_word(PC_ENV *m, uint16 s)\r |
| 1423 | {\r |
| 1424 | uint32 res = m->R_AX * s;\r |
| 1425 | /* Undef --- Can't hurt */\r |
| 1426 | CLEAR_FLAG(m,F_SF);\r |
| 1427 | CONDITIONAL_SET_FLAG(res==0,m,F_ZF);\r |
| 1428 | m->R_AX = res & 0xffff;\r |
| 1429 | m->R_DX = (res >> 16) & 0xffff;\r |
| 1430 | if (m->R_DX == 0)\r |
| 1431 | {\r |
| 1432 | CLEAR_FLAG(m, F_CF);\r |
| 1433 | CLEAR_FLAG(m, F_OF);\r |
| 1434 | }\r |
| 1435 | else\r |
| 1436 | {\r |
| 1437 | SET_FLAG(m, F_CF);\r |
| 1438 | SET_FLAG(m, F_OF);\r |
| 1439 | }\r |
| 1440 | }\r |
| 1441 | \r |
| 1442 | void idiv_byte(PC_ENV *m, uint8 s)\r |
| 1443 | {\r |
| 1444 | int32 dvd,div,mod;\r |
| 1445 | dvd = (int16)m->R_AX;\r |
| 1446 | if (s == 0)\r |
| 1447 | {\r |
| 1448 | i86_intr_raise(m,0);\r |
| 1449 | return;\r |
| 1450 | }\r |
| 1451 | div = dvd / (int8)s;\r |
| 1452 | mod = dvd % (int8)s;\r |
| 1453 | if (abs(div) > 0x7f)\r |
| 1454 | {\r |
| 1455 | i86_intr_raise(m,0);\r |
| 1456 | return;\r |
| 1457 | }\r |
| 1458 | /* Undef --- Can't hurt */\r |
| 1459 | CONDITIONAL_SET_FLAG(div&0x80,m,F_SF);\r |
| 1460 | CONDITIONAL_SET_FLAG(div==0,m,F_ZF);\r |
| 1461 | m->R_AL = (int8)div;\r |
| 1462 | m->R_AH = (int8)mod;\r |
| 1463 | }\r |
| 1464 | \r |
| 1465 | void idiv_word(PC_ENV *m, uint16 s)\r |
| 1466 | {\r |
| 1467 | int32 dvd,dvs,div,mod;\r |
| 1468 | dvd = m->R_DX;\r |
| 1469 | dvd = (dvd << 16) | m->R_AX;\r |
| 1470 | if (s == 0)\r |
| 1471 | {\r |
| 1472 | i86_intr_raise(m,0);\r |
| 1473 | return;\r |
| 1474 | }\r |
| 1475 | dvs = (int16)s;\r |
| 1476 | div = dvd / dvs;\r |
| 1477 | mod = dvd % dvs;\r |
| 1478 | if (abs(div) > 0x7fff)\r |
| 1479 | {\r |
| 1480 | i86_intr_raise(m,0);\r |
| 1481 | return;\r |
| 1482 | }\r |
| 1483 | /* Undef --- Can't hurt */\r |
| 1484 | CONDITIONAL_SET_FLAG(div&0x8000,m,F_SF);\r |
| 1485 | CONDITIONAL_SET_FLAG(div==0,m,F_ZF);\r |
| 1486 | /* debug_printf(m, "\n%d/%d=%d,%d\n",dvd,dvs,div,mod); */\r |
| 1487 | m->R_AX = div;\r |
| 1488 | m->R_DX = mod;\r |
| 1489 | }\r |
| 1490 | \r |
| 1491 | void div_byte(PC_ENV *m, uint8 s)\r |
| 1492 | {\r |
| 1493 | uint32 dvd,dvs,div,mod;\r |
| 1494 | dvs = s;\r |
| 1495 | dvd = m->R_AX;\r |
| 1496 | if (s == 0)\r |
| 1497 | {\r |
| 1498 | i86_intr_raise(m,0);\r |
| 1499 | return;\r |
| 1500 | }\r |
| 1501 | div = dvd / dvs;\r |
| 1502 | mod = dvd % dvs;\r |
| 1503 | if (abs(div) > 0xff)\r |
| 1504 | {\r |
| 1505 | i86_intr_raise(m,0);\r |
| 1506 | return;\r |
| 1507 | }\r |
| 1508 | /* Undef --- Can't hurt */\r |
| 1509 | CLEAR_FLAG(m,F_SF);\r |
| 1510 | CONDITIONAL_SET_FLAG(div==0,m,F_ZF);\r |
| 1511 | m->R_AL = (uint8)div;\r |
| 1512 | m->R_AH = (uint8)mod;\r |
| 1513 | }\r |
| 1514 | \r |
| 1515 | void div_word(PC_ENV *m, uint16 s)\r |
| 1516 | {\r |
| 1517 | uint32 dvd,dvs,div,mod;\r |
| 1518 | dvd = m->R_DX;\r |
| 1519 | dvd = (dvd << 16) | m->R_AX;\r |
| 1520 | dvs = s;\r |
| 1521 | if (dvs == 0)\r |
| 1522 | {\r |
| 1523 | i86_intr_raise(m,0);\r |
| 1524 | return;\r |
| 1525 | }\r |
| 1526 | div = dvd / dvs;\r |
| 1527 | mod = dvd % dvs;\r |
| 1528 | /* printf("dvd=%x dvs=%x -> div=%x mod=%x\n",dvd, dvs,div, mod);*/\r |
| 1529 | if (abs(div) > 0xffff)\r |
| 1530 | {\r |
| 1531 | i86_intr_raise(m,0);\r |
| 1532 | return;\r |
| 1533 | }\r |
| 1534 | /* Undef --- Can't hurt */\r |
| 1535 | CLEAR_FLAG(m,F_SF);\r |
| 1536 | CONDITIONAL_SET_FLAG(div==0,m,F_ZF);\r |
| 1537 | m->R_AX = div;\r |
| 1538 | m->R_DX = mod;\r |
| 1539 | }\r |