target-s390x/fpu_helper.c

   1 /*
   2  *  S/390 FPU helper routines
   3  *
   4  *  Copyright (c) 2009 Ulrich Hecht
   5  *  Copyright (c) 2009 Alexander Graf
   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 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, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "cpu.h"
  22 #include "helper.h"
  23
  24 #if !defined(CONFIG_USER_ONLY)
  25 #include "exec/softmmu_exec.h"
  26 #endif
  27
  28 /* #define DEBUG_HELPER */
  29 #ifdef DEBUG_HELPER
  30 #define HELPER_LOG(x...) qemu_log(x)
  31 #else
  32 #define HELPER_LOG(x...)
  33 #endif
  34
  35 #define RET128(F) (env->retxl = F.low, F.high)
  36
  37 #define convert_bit(mask, from, to) \
  38     (to < from                      \
  39      ? (mask / (from / to)) & to    \
  40      : (mask & from) * (to / from))
  41
  42 static void ieee_exception(CPUS390XState *env, uint32_t dxc, uintptr_t retaddr)
  43 {
  44     /* Install the DXC code.  */
  45     env->fpc = (env->fpc & ~0xff00) | (dxc << 8);
  46     /* Trap.  */
  47     runtime_exception(env, PGM_DATA, retaddr);
  48 }
  49
  50 /* Should be called after any operation that may raise IEEE exceptions.  */
  51 static void handle_exceptions(CPUS390XState *env, uintptr_t retaddr)
  52 {
  53     unsigned s390_exc, qemu_exc;
  54
  55     /* Get the exceptions raised by the current operation.  Reset the
  56        fpu_status contents so that the next operation has a clean slate.  */
  57     qemu_exc = env->fpu_status.float_exception_flags;
  58     if (qemu_exc == 0) {
  59         return;
  60     }
  61     env->fpu_status.float_exception_flags = 0;
  62
  63     /* Convert softfloat exception bits to s390 exception bits.  */
  64     s390_exc = 0;
  65     s390_exc |= convert_bit(qemu_exc, float_flag_invalid, 0x80);
  66     s390_exc |= convert_bit(qemu_exc, float_flag_divbyzero, 0x40);
  67     s390_exc |= convert_bit(qemu_exc, float_flag_overflow, 0x20);
  68     s390_exc |= convert_bit(qemu_exc, float_flag_underflow, 0x10);
  69     s390_exc |= convert_bit(qemu_exc, float_flag_inexact, 0x08);
  70
  71     /* Install the exceptions that we raised.  */
  72     env->fpc |= s390_exc << 16;
  73
  74     /* Send signals for enabled exceptions.  */
  75     s390_exc &= env->fpc >> 24;
  76     if (s390_exc) {
  77         ieee_exception(env, s390_exc, retaddr);
  78     }
  79 }
  80
  81 static inline int float_comp_to_cc(CPUS390XState *env, int float_compare)
  82 {
  83     switch (float_compare) {
  84     case float_relation_equal:
  85         return 0;
  86     case float_relation_less:
  87         return 1;
  88     case float_relation_greater:
  89         return 2;
  90     case float_relation_unordered:
  91         return 3;
  92     default:
  93         cpu_abort(env, "unknown return value for float compare\n");
  94     }
  95 }
  96
  97 /* condition codes for unary FP ops */
  98 uint32_t set_cc_nz_f32(float32 v)
  99 {
 100     if (float32_is_any_nan(v)) {
 101         return 3;
 102     } else if (float32_is_zero(v)) {
 103         return 0;
 104     } else if (float32_is_neg(v)) {
 105         return 1;
 106     } else {
 107         return 2;
 108     }
 109 }
 110
 111 uint32_t set_cc_nz_f64(float64 v)
 112 {
 113     if (float64_is_any_nan(v)) {
 114         return 3;
 115     } else if (float64_is_zero(v)) {
 116         return 0;
 117     } else if (float64_is_neg(v)) {
 118         return 1;
 119     } else {
 120         return 2;
 121     }
 122 }
 123
 124 uint32_t set_cc_nz_f128(float128 v)
 125 {
 126     if (float128_is_any_nan(v)) {
 127         return 3;
 128     } else if (float128_is_zero(v)) {
 129         return 0;
 130     } else if (float128_is_neg(v)) {
 131         return 1;
 132     } else {
 133         return 2;
 134     }
 135 }
 136
 137 /* 32-bit FP addition */
 138 uint64_t HELPER(aeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 139 {
 140     float32 ret = float32_add(f1, f2, &env->fpu_status);
 141     handle_exceptions(env, GETPC());
 142     return ret;
 143 }
 144
 145 /* 64-bit FP addition */
 146 uint64_t HELPER(adb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 147 {
 148     float64 ret = float64_add(f1, f2, &env->fpu_status);
 149     handle_exceptions(env, GETPC());
 150     return ret;
 151 }
 152
 153 /* 128-bit FP addition */
 154 uint64_t HELPER(axb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 155                      uint64_t bh, uint64_t bl)
 156 {
 157     float128 ret = float128_add(make_float128(ah, al),
 158                                 make_float128(bh, bl),
 159                                 &env->fpu_status);
 160     handle_exceptions(env, GETPC());
 161     return RET128(ret);
 162 }
 163
 164 /* 32-bit FP subtraction */
 165 uint64_t HELPER(seb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 166 {
 167     float32 ret = float32_sub(f1, f2, &env->fpu_status);
 168     handle_exceptions(env, GETPC());
 169     return ret;
 170 }
 171
 172 /* 64-bit FP subtraction */
 173 uint64_t HELPER(sdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 174 {
 175     float64 ret = float64_sub(f1, f2, &env->fpu_status);
 176     handle_exceptions(env, GETPC());
 177     return ret;
 178 }
 179
 180 /* 128-bit FP subtraction */
 181 uint64_t HELPER(sxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 182                      uint64_t bh, uint64_t bl)
 183 {
 184     float128 ret = float128_sub(make_float128(ah, al),
 185                                 make_float128(bh, bl),
 186                                 &env->fpu_status);
 187     handle_exceptions(env, GETPC());
 188     return RET128(ret);
 189 }
 190
 191 /* 32-bit FP division */
 192 uint64_t HELPER(deb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 193 {
 194     float32 ret = float32_div(f1, f2, &env->fpu_status);
 195     handle_exceptions(env, GETPC());
 196     return ret;
 197 }
 198
 199 /* 64-bit FP division */
 200 uint64_t HELPER(ddb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 201 {
 202     float64 ret = float64_div(f1, f2, &env->fpu_status);
 203     handle_exceptions(env, GETPC());
 204     return ret;
 205 }
 206
 207 /* 128-bit FP division */
 208 uint64_t HELPER(dxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 209                      uint64_t bh, uint64_t bl)
 210 {
 211     float128 ret = float128_div(make_float128(ah, al),
 212                                 make_float128(bh, bl),
 213                                 &env->fpu_status);
 214     handle_exceptions(env, GETPC());
 215     return RET128(ret);
 216 }
 217
 218 /* 32-bit FP multiplication */
 219 uint64_t HELPER(meeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 220 {
 221     float32 ret = float32_mul(f1, f2, &env->fpu_status);
 222     handle_exceptions(env, GETPC());
 223     return ret;
 224 }
 225
 226 /* 64-bit FP multiplication */
 227 uint64_t HELPER(mdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 228 {
 229     float64 ret = float64_mul(f1, f2, &env->fpu_status);
 230     handle_exceptions(env, GETPC());
 231     return ret;
 232 }
 233
 234 /* 64/32-bit FP multiplication */
 235 uint64_t HELPER(mdeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 236 {
 237     float64 ret = float32_to_float64(f2, &env->fpu_status);
 238     ret = float64_mul(f1, ret, &env->fpu_status);
 239     handle_exceptions(env, GETPC());
 240     return ret;
 241 }
 242
 243 /* 128-bit FP multiplication */
 244 uint64_t HELPER(mxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 245                      uint64_t bh, uint64_t bl)
 246 {
 247     float128 ret = float128_mul(make_float128(ah, al),
 248                                 make_float128(bh, bl),
 249                                 &env->fpu_status);
 250     handle_exceptions(env, GETPC());
 251     return RET128(ret);
 252 }
 253
 254 /* 128/64-bit FP multiplication */
 255 uint64_t HELPER(mxdb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 256                       uint64_t f2)
 257 {
 258     float128 ret = float64_to_float128(f2, &env->fpu_status);
 259     ret = float128_mul(make_float128(ah, al), ret, &env->fpu_status);
 260     handle_exceptions(env, GETPC());
 261     return RET128(ret);
 262 }
 263
 264 /* convert 32-bit float to 64-bit float */
 265 uint64_t HELPER(ldeb)(CPUS390XState *env, uint64_t f2)
 266 {
 267     float64 ret = float32_to_float64(f2, &env->fpu_status);
 268     handle_exceptions(env, GETPC());
 269     return ret;
 270 }
 271
 272 /* convert 128-bit float to 64-bit float */
 273 uint64_t HELPER(ldxb)(CPUS390XState *env, uint64_t ah, uint64_t al)
 274 {
 275     float64 ret = float128_to_float64(make_float128(ah, al), &env->fpu_status);
 276     handle_exceptions(env, GETPC());
 277     return ret;
 278 }
 279
 280 /* convert 64-bit float to 128-bit float */
 281 uint64_t HELPER(lxdb)(CPUS390XState *env, uint64_t f2)
 282 {
 283     float128 ret = float64_to_float128(f2, &env->fpu_status);
 284     handle_exceptions(env, GETPC());
 285     return RET128(ret);
 286 }
 287
 288 /* convert 32-bit float to 128-bit float */
 289 uint64_t HELPER(lxeb)(CPUS390XState *env, uint64_t f2)
 290 {
 291     float128 ret = float32_to_float128(f2, &env->fpu_status);
 292     handle_exceptions(env, GETPC());
 293     return RET128(ret);
 294 }
 295
 296 /* convert 64-bit float to 32-bit float */
 297 uint64_t HELPER(ledb)(CPUS390XState *env, uint64_t f2)
 298 {
 299     float32 ret = float64_to_float32(f2, &env->fpu_status);
 300     handle_exceptions(env, GETPC());
 301     return ret;
 302 }
 303
 304 /* convert 128-bit float to 32-bit float */
 305 uint64_t HELPER(lexb)(CPUS390XState *env, uint64_t ah, uint64_t al)
 306 {
 307     float32 ret = float128_to_float32(make_float128(ah, al), &env->fpu_status);
 308     handle_exceptions(env, GETPC());
 309     return ret;
 310 }
 311
 312 /* 32-bit FP compare */
 313 uint32_t HELPER(ceb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 314 {
 315     int cmp = float32_compare_quiet(f1, f2, &env->fpu_status);
 316     handle_exceptions(env, GETPC());
 317     return float_comp_to_cc(env, cmp);
 318 }
 319
 320 /* 64-bit FP compare */
 321 uint32_t HELPER(cdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 322 {
 323     int cmp = float64_compare_quiet(f1, f2, &env->fpu_status);
 324     handle_exceptions(env, GETPC());
 325     return float_comp_to_cc(env, cmp);
 326 }
 327
 328 /* 128-bit FP compare */
 329 uint32_t HELPER(cxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 330                      uint64_t bh, uint64_t bl)
 331 {
 332     int cmp = float128_compare_quiet(make_float128(ah, al),
 333                                      make_float128(bh, bl),
 334                                      &env->fpu_status);
 335     handle_exceptions(env, GETPC());
 336     return float_comp_to_cc(env, cmp);
 337 }
 338
 339 static int swap_round_mode(CPUS390XState *env, int m3)
 340 {
 341     int ret = env->fpu_status.float_rounding_mode;
 342     switch (m3) {
 343     case 0:
 344         /* current mode */
 345         break;
 346     case 1:
 347         /* biased round no nearest */
 348     case 4:
 349         /* round to nearest */
 350         set_float_rounding_mode(float_round_nearest_even, &env->fpu_status);
 351         break;
 352     case 5:
 353         /* round to zero */
 354         set_float_rounding_mode(float_round_to_zero, &env->fpu_status);
 355         break;
 356     case 6:
 357         /* round to +inf */
 358         set_float_rounding_mode(float_round_up, &env->fpu_status);
 359         break;
 360     case 7:
 361         /* round to -inf */
 362         set_float_rounding_mode(float_round_down, &env->fpu_status);
 363         break;
 364     }
 365     return ret;
 366 }
 367
 368 /* convert 64-bit int to 32-bit float */
 369 uint64_t HELPER(cegb)(CPUS390XState *env, int64_t v2, uint32_t m3)
 370 {
 371     int hold = swap_round_mode(env, m3);
 372     float32 ret = int64_to_float32(v2, &env->fpu_status);
 373     set_float_rounding_mode(hold, &env->fpu_status);
 374     handle_exceptions(env, GETPC());
 375     return ret;
 376 }
 377
 378 /* convert 64-bit int to 64-bit float */
 379 uint64_t HELPER(cdgb)(CPUS390XState *env, int64_t v2, uint32_t m3)
 380 {
 381     int hold = swap_round_mode(env, m3);
 382     float64 ret = int64_to_float64(v2, &env->fpu_status);
 383     set_float_rounding_mode(hold, &env->fpu_status);
 384     handle_exceptions(env, GETPC());
 385     return ret;
 386 }
 387
 388 /* convert 64-bit int to 128-bit float */
 389 uint64_t HELPER(cxgb)(CPUS390XState *env, int64_t v2, uint32_t m3)
 390 {
 391     int hold = swap_round_mode(env, m3);
 392     float128 ret = int64_to_float128(v2, &env->fpu_status);
 393     set_float_rounding_mode(hold, &env->fpu_status);
 394     handle_exceptions(env, GETPC());
 395     return RET128(ret);
 396 }
 397
 398 /* convert 32-bit float to 64-bit int */
 399 uint64_t HELPER(cgeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 400 {
 401     int hold = swap_round_mode(env, m3);
 402     int64_t ret = float32_to_int64(v2, &env->fpu_status);
 403     set_float_rounding_mode(hold, &env->fpu_status);
 404     handle_exceptions(env, GETPC());
 405     return ret;
 406 }
 407
 408 /* convert 64-bit float to 64-bit int */
 409 uint64_t HELPER(cgdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 410 {
 411     int hold = swap_round_mode(env, m3);
 412     int64_t ret = float64_to_int64(v2, &env->fpu_status);
 413     set_float_rounding_mode(hold, &env->fpu_status);
 414     handle_exceptions(env, GETPC());
 415     return ret;
 416 }
 417
 418 /* convert 128-bit float to 64-bit int */
 419 uint64_t HELPER(cgxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
 420 {
 421     int hold = swap_round_mode(env, m3);
 422     float128 v2 = make_float128(h, l);
 423     int64_t ret = float128_to_int64(v2, &env->fpu_status);
 424     set_float_rounding_mode(hold, &env->fpu_status);
 425     handle_exceptions(env, GETPC());
 426     return ret;
 427 }
 428
 429 /* convert 32-bit float to 32-bit int */
 430 uint64_t HELPER(cfeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 431 {
 432     int hold = swap_round_mode(env, m3);
 433     int32_t ret = float32_to_int32(v2, &env->fpu_status);
 434     set_float_rounding_mode(hold, &env->fpu_status);
 435     handle_exceptions(env, GETPC());
 436     return ret;
 437 }
 438
 439 /* convert 64-bit float to 32-bit int */
 440 uint64_t HELPER(cfdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 441 {
 442     int hold = swap_round_mode(env, m3);
 443     int32_t ret = float64_to_int32(v2, &env->fpu_status);
 444     set_float_rounding_mode(hold, &env->fpu_status);
 445     handle_exceptions(env, GETPC());
 446     return ret;
 447 }
 448
 449 /* convert 128-bit float to 32-bit int */
 450 uint64_t HELPER(cfxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
 451 {
 452     int hold = swap_round_mode(env, m3);
 453     float128 v2 = make_float128(h, l);
 454     int32_t ret = float128_to_int32(v2, &env->fpu_status);
 455     set_float_rounding_mode(hold, &env->fpu_status);
 456     handle_exceptions(env, GETPC());
 457     return ret;
 458 }
 459
 460 /* convert 32-bit float to 64-bit uint */
 461 uint64_t HELPER(clgeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 462 {
 463     int hold = swap_round_mode(env, m3);
 464     uint64_t ret;
 465     v2 = float32_to_float64(v2, &env->fpu_status);
 466     ret = float64_to_uint64(v2, &env->fpu_status);
 467     set_float_rounding_mode(hold, &env->fpu_status);
 468     handle_exceptions(env, GETPC());
 469     return ret;
 470 }
 471
 472 /* convert 64-bit float to 64-bit uint */
 473 uint64_t HELPER(clgdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 474 {
 475     int hold = swap_round_mode(env, m3);
 476     uint64_t ret = float64_to_uint64(v2, &env->fpu_status);
 477     set_float_rounding_mode(hold, &env->fpu_status);
 478     handle_exceptions(env, GETPC());
 479     return ret;
 480 }
 481
 482 /* convert 128-bit float to 64-bit uint */
 483 uint64_t HELPER(clgxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
 484 {
 485     int hold = swap_round_mode(env, m3);
 486     float128 v2 = make_float128(h, l);
 487     /* ??? Not 100% correct.  */
 488     uint64_t ret = float128_to_int64(v2, &env->fpu_status);
 489     set_float_rounding_mode(hold, &env->fpu_status);
 490     handle_exceptions(env, GETPC());
 491     return ret;
 492 }
 493
 494 /* convert 32-bit float to 32-bit uint */
 495 uint64_t HELPER(clfeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 496 {
 497     int hold = swap_round_mode(env, m3);
 498     uint32_t ret = float32_to_uint32(v2, &env->fpu_status);
 499     set_float_rounding_mode(hold, &env->fpu_status);
 500     handle_exceptions(env, GETPC());
 501     return ret;
 502 }
 503
 504 /* convert 64-bit float to 32-bit uint */
 505 uint64_t HELPER(clfdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
 506 {
 507     int hold = swap_round_mode(env, m3);
 508     uint32_t ret = float64_to_uint32(v2, &env->fpu_status);
 509     set_float_rounding_mode(hold, &env->fpu_status);
 510     handle_exceptions(env, GETPC());
 511     return ret;
 512 }
 513
 514 /* convert 128-bit float to 32-bit uint */
 515 uint64_t HELPER(clfxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
 516 {
 517     int hold = swap_round_mode(env, m3);
 518     float128 v2 = make_float128(h, l);
 519     /* Not 100% correct.  */
 520     uint32_t ret = float128_to_int64(v2, &env->fpu_status);
 521     set_float_rounding_mode(hold, &env->fpu_status);
 522     handle_exceptions(env, GETPC());
 523     return ret;
 524 }
 525
 526 /* 32-bit FP multiply and add */
 527 uint64_t HELPER(maeb)(CPUS390XState *env, uint64_t f1,
 528                       uint64_t f2, uint64_t f3)
 529 {
 530     float32 ret = float32_muladd(f2, f3, f1, 0, &env->fpu_status);
 531     handle_exceptions(env, GETPC());
 532     return ret;
 533 }
 534
 535 /* 64-bit FP multiply and add */
 536 uint64_t HELPER(madb)(CPUS390XState *env, uint64_t f1,
 537                       uint64_t f2, uint64_t f3)
 538 {
 539     float64 ret = float64_muladd(f2, f3, f1, 0, &env->fpu_status);
 540     handle_exceptions(env, GETPC());
 541     return ret;
 542 }
 543
 544 /* 32-bit FP multiply and subtract */
 545 uint64_t HELPER(mseb)(CPUS390XState *env, uint64_t f1,
 546                       uint64_t f2, uint64_t f3)
 547 {
 548     float32 ret = float32_muladd(f2, f3, f1, float_muladd_negate_c,
 549                                  &env->fpu_status);
 550     handle_exceptions(env, GETPC());
 551     return ret;
 552 }
 553
 554 /* 64-bit FP multiply and subtract */
 555 uint64_t HELPER(msdb)(CPUS390XState *env, uint64_t f1,
 556                       uint64_t f2, uint64_t f3)
 557 {
 558     float64 ret = float64_muladd(f2, f3, f1, float_muladd_negate_c,
 559                                  &env->fpu_status);
 560     handle_exceptions(env, GETPC());
 561     return ret;
 562 }
 563
 564 /* test data class 32-bit */
 565 uint32_t HELPER(tceb)(uint64_t f1, uint64_t m2)
 566 {
 567     float32 v1 = f1;
 568     int neg = float32_is_neg(v1);
 569     uint32_t cc = 0;
 570
 571     if ((float32_is_zero(v1) && (m2 & (1 << (11-neg)))) ||
 572         (float32_is_infinity(v1) && (m2 & (1 << (5-neg)))) ||
 573         (float32_is_any_nan(v1) && (m2 & (1 << (3-neg)))) ||
 574         (float32_is_signaling_nan(v1) && (m2 & (1 << (1-neg))))) {
 575         cc = 1;
 576     } else if (m2 & (1 << (9-neg))) {
 577         /* assume normalized number */
 578         cc = 1;
 579     }
 580     /* FIXME: denormalized? */
 581     return cc;
 582 }
 583
 584 /* test data class 64-bit */
 585 uint32_t HELPER(tcdb)(uint64_t v1, uint64_t m2)
 586 {
 587     int neg = float64_is_neg(v1);
 588     uint32_t cc = 0;
 589
 590     if ((float64_is_zero(v1) && (m2 & (1 << (11-neg)))) ||
 591         (float64_is_infinity(v1) && (m2 & (1 << (5-neg)))) ||
 592         (float64_is_any_nan(v1) && (m2 & (1 << (3-neg)))) ||
 593         (float64_is_signaling_nan(v1) && (m2 & (1 << (1-neg))))) {
 594         cc = 1;
 595     } else if (m2 & (1 << (9-neg))) {
 596         /* assume normalized number */
 597         cc = 1;
 598     }
 599     /* FIXME: denormalized? */
 600     return cc;
 601 }
 602
 603 /* test data class 128-bit */
 604 uint32_t HELPER(tcxb)(uint64_t ah, uint64_t al, uint64_t m2)
 605 {
 606     float128 v1 = make_float128(ah, al);
 607     int neg = float128_is_neg(v1);
 608     uint32_t cc = 0;
 609
 610     if ((float128_is_zero(v1) && (m2 & (1 << (11-neg)))) ||
 611         (float128_is_infinity(v1) && (m2 & (1 << (5-neg)))) ||
 612         (float128_is_any_nan(v1) && (m2 & (1 << (3-neg)))) ||
 613         (float128_is_signaling_nan(v1) && (m2 & (1 << (1-neg))))) {
 614         cc = 1;
 615     } else if (m2 & (1 << (9-neg))) {
 616         /* assume normalized number */
 617         cc = 1;
 618     }
 619     /* FIXME: denormalized? */
 620     return cc;
 621 }
 622
 623 /* square root 32-bit */
 624 uint64_t HELPER(sqeb)(CPUS390XState *env, uint64_t f2)
 625 {
 626     float32 ret = float32_sqrt(f2, &env->fpu_status);
 627     handle_exceptions(env, GETPC());
 628     return ret;
 629 }
 630
 631 /* square root 64-bit */
 632 uint64_t HELPER(sqdb)(CPUS390XState *env, uint64_t f2)
 633 {
 634     float64 ret = float64_sqrt(f2, &env->fpu_status);
 635     handle_exceptions(env, GETPC());
 636     return ret;
 637 }
 638
 639 /* square root 128-bit */
 640 uint64_t HELPER(sqxb)(CPUS390XState *env, uint64_t ah, uint64_t al)
 641 {
 642     float128 ret = float128_sqrt(make_float128(ah, al), &env->fpu_status);
 643     handle_exceptions(env, GETPC());
 644     return RET128(ret);
 645 }
 646
 647 /* set fpc */
 648 void HELPER(sfpc)(CPUS390XState *env, uint64_t fpc)
 649 {
 650     static const int rnd[4] = {
 651         float_round_nearest_even,
 652         float_round_to_zero,
 653         float_round_up,
 654         float_round_down
 655     };
 656
 657     /* Install everything in the main FPC.  */
 658     env->fpc = fpc;
 659
 660     /* Install the rounding mode in the shadow fpu_status.  */
 661     set_float_rounding_mode(rnd[fpc & 3], &env->fpu_status);
 662 }