| 1 | /* |
| 2 | * Helpers for vax floating point instructions. |
| 3 | * |
| 4 | * Copyright (c) 2007 Jocelyn Mayer |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| 18 | */ |
| 19 | |
| 20 | #include "qemu/osdep.h" |
| 21 | #include "cpu.h" |
| 22 | #include "exec/helper-proto.h" |
| 23 | #include "fpu/softfloat.h" |
| 24 | |
| 25 | #define FP_STATUS (env->fp_status) |
| 26 | |
| 27 | |
| 28 | /* F floating (VAX) */ |
| 29 | static uint64_t float32_to_f(float32 fa) |
| 30 | { |
| 31 | uint64_t r, exp, mant, sig; |
| 32 | CPU_FloatU a; |
| 33 | |
| 34 | a.f = fa; |
| 35 | sig = ((uint64_t)a.l & 0x80000000) << 32; |
| 36 | exp = (a.l >> 23) & 0xff; |
| 37 | mant = ((uint64_t)a.l & 0x007fffff) << 29; |
| 38 | |
| 39 | if (exp == 255) { |
| 40 | /* NaN or infinity */ |
| 41 | r = 1; /* VAX dirty zero */ |
| 42 | } else if (exp == 0) { |
| 43 | if (mant == 0) { |
| 44 | /* Zero */ |
| 45 | r = 0; |
| 46 | } else { |
| 47 | /* Denormalized */ |
| 48 | r = sig | ((exp + 1) << 52) | mant; |
| 49 | } |
| 50 | } else { |
| 51 | if (exp >= 253) { |
| 52 | /* Overflow */ |
| 53 | r = 1; /* VAX dirty zero */ |
| 54 | } else { |
| 55 | r = sig | ((exp + 2) << 52); |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | return r; |
| 60 | } |
| 61 | |
| 62 | static float32 f_to_float32(CPUAlphaState *env, uintptr_t retaddr, uint64_t a) |
| 63 | { |
| 64 | uint32_t exp, mant_sig; |
| 65 | CPU_FloatU r; |
| 66 | |
| 67 | exp = ((a >> 55) & 0x80) | ((a >> 52) & 0x7f); |
| 68 | mant_sig = ((a >> 32) & 0x80000000) | ((a >> 29) & 0x007fffff); |
| 69 | |
| 70 | if (unlikely(!exp && mant_sig)) { |
| 71 | /* Reserved operands / Dirty zero */ |
| 72 | dynamic_excp(env, retaddr, EXCP_OPCDEC, 0); |
| 73 | } |
| 74 | |
| 75 | if (exp < 3) { |
| 76 | /* Underflow */ |
| 77 | r.l = 0; |
| 78 | } else { |
| 79 | r.l = ((exp - 2) << 23) | mant_sig; |
| 80 | } |
| 81 | |
| 82 | return r.f; |
| 83 | } |
| 84 | |
| 85 | uint32_t helper_f_to_memory(uint64_t a) |
| 86 | { |
| 87 | uint32_t r; |
| 88 | r = (a & 0x00001fffe0000000ull) >> 13; |
| 89 | r |= (a & 0x07ffe00000000000ull) >> 45; |
| 90 | r |= (a & 0xc000000000000000ull) >> 48; |
| 91 | return r; |
| 92 | } |
| 93 | |
| 94 | uint64_t helper_memory_to_f(uint32_t a) |
| 95 | { |
| 96 | uint64_t r; |
| 97 | r = ((uint64_t)(a & 0x0000c000)) << 48; |
| 98 | r |= ((uint64_t)(a & 0x003fffff)) << 45; |
| 99 | r |= ((uint64_t)(a & 0xffff0000)) << 13; |
| 100 | if (!(a & 0x00004000)) { |
| 101 | r |= 0x7ll << 59; |
| 102 | } |
| 103 | return r; |
| 104 | } |
| 105 | |
| 106 | /* ??? Emulating VAX arithmetic with IEEE arithmetic is wrong. We should |
| 107 | either implement VAX arithmetic properly or just signal invalid opcode. */ |
| 108 | |
| 109 | uint64_t helper_addf(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 110 | { |
| 111 | float32 fa, fb, fr; |
| 112 | |
| 113 | fa = f_to_float32(env, GETPC(), a); |
| 114 | fb = f_to_float32(env, GETPC(), b); |
| 115 | fr = float32_add(fa, fb, &FP_STATUS); |
| 116 | return float32_to_f(fr); |
| 117 | } |
| 118 | |
| 119 | uint64_t helper_subf(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 120 | { |
| 121 | float32 fa, fb, fr; |
| 122 | |
| 123 | fa = f_to_float32(env, GETPC(), a); |
| 124 | fb = f_to_float32(env, GETPC(), b); |
| 125 | fr = float32_sub(fa, fb, &FP_STATUS); |
| 126 | return float32_to_f(fr); |
| 127 | } |
| 128 | |
| 129 | uint64_t helper_mulf(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 130 | { |
| 131 | float32 fa, fb, fr; |
| 132 | |
| 133 | fa = f_to_float32(env, GETPC(), a); |
| 134 | fb = f_to_float32(env, GETPC(), b); |
| 135 | fr = float32_mul(fa, fb, &FP_STATUS); |
| 136 | return float32_to_f(fr); |
| 137 | } |
| 138 | |
| 139 | uint64_t helper_divf(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 140 | { |
| 141 | float32 fa, fb, fr; |
| 142 | |
| 143 | fa = f_to_float32(env, GETPC(), a); |
| 144 | fb = f_to_float32(env, GETPC(), b); |
| 145 | fr = float32_div(fa, fb, &FP_STATUS); |
| 146 | return float32_to_f(fr); |
| 147 | } |
| 148 | |
| 149 | uint64_t helper_sqrtf(CPUAlphaState *env, uint64_t t) |
| 150 | { |
| 151 | float32 ft, fr; |
| 152 | |
| 153 | ft = f_to_float32(env, GETPC(), t); |
| 154 | fr = float32_sqrt(ft, &FP_STATUS); |
| 155 | return float32_to_f(fr); |
| 156 | } |
| 157 | |
| 158 | |
| 159 | /* G floating (VAX) */ |
| 160 | static uint64_t float64_to_g(float64 fa) |
| 161 | { |
| 162 | uint64_t r, exp, mant, sig; |
| 163 | CPU_DoubleU a; |
| 164 | |
| 165 | a.d = fa; |
| 166 | sig = a.ll & 0x8000000000000000ull; |
| 167 | exp = (a.ll >> 52) & 0x7ff; |
| 168 | mant = a.ll & 0x000fffffffffffffull; |
| 169 | |
| 170 | if (exp == 2047) { |
| 171 | /* NaN or infinity */ |
| 172 | r = 1; /* VAX dirty zero */ |
| 173 | } else if (exp == 0) { |
| 174 | if (mant == 0) { |
| 175 | /* Zero */ |
| 176 | r = 0; |
| 177 | } else { |
| 178 | /* Denormalized */ |
| 179 | r = sig | ((exp + 1) << 52) | mant; |
| 180 | } |
| 181 | } else { |
| 182 | if (exp >= 2045) { |
| 183 | /* Overflow */ |
| 184 | r = 1; /* VAX dirty zero */ |
| 185 | } else { |
| 186 | r = sig | ((exp + 2) << 52); |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | return r; |
| 191 | } |
| 192 | |
| 193 | static float64 g_to_float64(CPUAlphaState *env, uintptr_t retaddr, uint64_t a) |
| 194 | { |
| 195 | uint64_t exp, mant_sig; |
| 196 | CPU_DoubleU r; |
| 197 | |
| 198 | exp = (a >> 52) & 0x7ff; |
| 199 | mant_sig = a & 0x800fffffffffffffull; |
| 200 | |
| 201 | if (!exp && mant_sig) { |
| 202 | /* Reserved operands / Dirty zero */ |
| 203 | dynamic_excp(env, retaddr, EXCP_OPCDEC, 0); |
| 204 | } |
| 205 | |
| 206 | if (exp < 3) { |
| 207 | /* Underflow */ |
| 208 | r.ll = 0; |
| 209 | } else { |
| 210 | r.ll = ((exp - 2) << 52) | mant_sig; |
| 211 | } |
| 212 | |
| 213 | return r.d; |
| 214 | } |
| 215 | |
| 216 | uint64_t helper_g_to_memory(uint64_t a) |
| 217 | { |
| 218 | uint64_t r; |
| 219 | r = (a & 0x000000000000ffffull) << 48; |
| 220 | r |= (a & 0x00000000ffff0000ull) << 16; |
| 221 | r |= (a & 0x0000ffff00000000ull) >> 16; |
| 222 | r |= (a & 0xffff000000000000ull) >> 48; |
| 223 | return r; |
| 224 | } |
| 225 | |
| 226 | uint64_t helper_memory_to_g(uint64_t a) |
| 227 | { |
| 228 | uint64_t r; |
| 229 | r = (a & 0x000000000000ffffull) << 48; |
| 230 | r |= (a & 0x00000000ffff0000ull) << 16; |
| 231 | r |= (a & 0x0000ffff00000000ull) >> 16; |
| 232 | r |= (a & 0xffff000000000000ull) >> 48; |
| 233 | return r; |
| 234 | } |
| 235 | |
| 236 | uint64_t helper_addg(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 237 | { |
| 238 | float64 fa, fb, fr; |
| 239 | |
| 240 | fa = g_to_float64(env, GETPC(), a); |
| 241 | fb = g_to_float64(env, GETPC(), b); |
| 242 | fr = float64_add(fa, fb, &FP_STATUS); |
| 243 | return float64_to_g(fr); |
| 244 | } |
| 245 | |
| 246 | uint64_t helper_subg(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 247 | { |
| 248 | float64 fa, fb, fr; |
| 249 | |
| 250 | fa = g_to_float64(env, GETPC(), a); |
| 251 | fb = g_to_float64(env, GETPC(), b); |
| 252 | fr = float64_sub(fa, fb, &FP_STATUS); |
| 253 | return float64_to_g(fr); |
| 254 | } |
| 255 | |
| 256 | uint64_t helper_mulg(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 257 | { |
| 258 | float64 fa, fb, fr; |
| 259 | |
| 260 | fa = g_to_float64(env, GETPC(), a); |
| 261 | fb = g_to_float64(env, GETPC(), b); |
| 262 | fr = float64_mul(fa, fb, &FP_STATUS); |
| 263 | return float64_to_g(fr); |
| 264 | } |
| 265 | |
| 266 | uint64_t helper_divg(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 267 | { |
| 268 | float64 fa, fb, fr; |
| 269 | |
| 270 | fa = g_to_float64(env, GETPC(), a); |
| 271 | fb = g_to_float64(env, GETPC(), b); |
| 272 | fr = float64_div(fa, fb, &FP_STATUS); |
| 273 | return float64_to_g(fr); |
| 274 | } |
| 275 | |
| 276 | uint64_t helper_sqrtg(CPUAlphaState *env, uint64_t a) |
| 277 | { |
| 278 | float64 fa, fr; |
| 279 | |
| 280 | fa = g_to_float64(env, GETPC(), a); |
| 281 | fr = float64_sqrt(fa, &FP_STATUS); |
| 282 | return float64_to_g(fr); |
| 283 | } |
| 284 | |
| 285 | uint64_t helper_cmpgeq(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 286 | { |
| 287 | float64 fa, fb; |
| 288 | |
| 289 | fa = g_to_float64(env, GETPC(), a); |
| 290 | fb = g_to_float64(env, GETPC(), b); |
| 291 | |
| 292 | if (float64_eq_quiet(fa, fb, &FP_STATUS)) { |
| 293 | return 0x4000000000000000ULL; |
| 294 | } else { |
| 295 | return 0; |
| 296 | } |
| 297 | } |
| 298 | |
| 299 | uint64_t helper_cmpgle(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 300 | { |
| 301 | float64 fa, fb; |
| 302 | |
| 303 | fa = g_to_float64(env, GETPC(), a); |
| 304 | fb = g_to_float64(env, GETPC(), b); |
| 305 | |
| 306 | if (float64_le(fa, fb, &FP_STATUS)) { |
| 307 | return 0x4000000000000000ULL; |
| 308 | } else { |
| 309 | return 0; |
| 310 | } |
| 311 | } |
| 312 | |
| 313 | uint64_t helper_cmpglt(CPUAlphaState *env, uint64_t a, uint64_t b) |
| 314 | { |
| 315 | float64 fa, fb; |
| 316 | |
| 317 | fa = g_to_float64(env, GETPC(), a); |
| 318 | fb = g_to_float64(env, GETPC(), b); |
| 319 | |
| 320 | if (float64_lt(fa, fb, &FP_STATUS)) { |
| 321 | return 0x4000000000000000ULL; |
| 322 | } else { |
| 323 | return 0; |
| 324 | } |
| 325 | } |
| 326 | |
| 327 | uint64_t helper_cvtqf(CPUAlphaState *env, uint64_t a) |
| 328 | { |
| 329 | float32 fr = int64_to_float32(a, &FP_STATUS); |
| 330 | return float32_to_f(fr); |
| 331 | } |
| 332 | |
| 333 | uint64_t helper_cvtgf(CPUAlphaState *env, uint64_t a) |
| 334 | { |
| 335 | float64 fa; |
| 336 | float32 fr; |
| 337 | |
| 338 | fa = g_to_float64(env, GETPC(), a); |
| 339 | fr = float64_to_float32(fa, &FP_STATUS); |
| 340 | return float32_to_f(fr); |
| 341 | } |
| 342 | |
| 343 | uint64_t helper_cvtgq(CPUAlphaState *env, uint64_t a) |
| 344 | { |
| 345 | float64 fa = g_to_float64(env, GETPC(), a); |
| 346 | return float64_to_int64_round_to_zero(fa, &FP_STATUS); |
| 347 | } |
| 348 | |
| 349 | uint64_t helper_cvtqg(CPUAlphaState *env, uint64_t a) |
| 350 | { |
| 351 | float64 fr; |
| 352 | fr = int64_to_float64(a, &FP_STATUS); |
| 353 | return float64_to_g(fr); |
| 354 | } |