sc_time.cc revision 13252
1/* 2 * Copyright 2018 Google, Inc. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: redistributions of source code must retain the above copyright 7 * notice, this list of conditions and the following disclaimer; 8 * redistributions in binary form must reproduce the above copyright 9 * notice, this list of conditions and the following disclaimer in the 10 * documentation and/or other materials provided with the distribution; 11 * neither the name of the copyright holders nor the names of its 12 * contributors may be used to endorse or promote products derived from 13 * this software without specific prior written permission. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * Authors: Gabe Black 28 */ 29 30#include <sstream> 31#include <vector> 32 33#include "base/logging.hh" 34#include "base/types.hh" 35#include "python/pybind11/pybind.hh" 36#include "sim/core.hh" 37#include "systemc/core/python.hh" 38#include "systemc/core/time.hh" 39#include "systemc/ext/core/sc_main.hh" 40#include "systemc/ext/core/sc_time.hh" 41#include "systemc/ext/utils/sc_report_handler.hh" 42 43namespace sc_core 44{ 45 46namespace 47{ 48 49bool timeFixed = false; 50bool pythonReady = false; 51 52struct SetInfo 53{ 54 SetInfo(::sc_core::sc_time *time, double d, ::sc_core::sc_time_unit tu) : 55 time(time), d(d), tu(tu) 56 {} 57 58 ::sc_core::sc_time *time; 59 double d; 60 ::sc_core::sc_time_unit tu; 61}; 62std::vector<SetInfo> toSet; 63 64void 65setWork(sc_time *time, double d, ::sc_core::sc_time_unit tu) 66{ 67 double scale = sc_gem5::TimeUnitScale[tu] * SimClock::Float::s; 68 // Accellera claims there is a linux bug, and that these next two 69 // lines work around them. 70 volatile double tmp = d * scale + 0.5; 71 *time = sc_time::from_value(static_cast<uint64_t>(tmp)); 72} 73 74void 75fixTime() 76{ 77 auto ticks = pybind11::module::import("m5.ticks"); 78 auto fix_global_frequency = ticks.attr("fixGlobalFrequency"); 79 fix_global_frequency(); 80 81 for (auto &t: toSet) 82 setWork(t.time, t.d, t.tu); 83 toSet.clear(); 84} 85 86void 87attemptToFixTime() 88{ 89 // Only fix time once. 90 if (!timeFixed) { 91 timeFixed = true; 92 93 // If we've run, python is working and we haven't fixed time yet. 94 if (pythonReady) 95 fixTime(); 96 } 97} 98 99void 100setGlobalFrequency(Tick ticks_per_second) 101{ 102 auto ticks = pybind11::module::import("m5.ticks"); 103 auto set_global_frequency = ticks.attr("setGlobalFrequency"); 104 set_global_frequency(ticks_per_second); 105 fixTime(); 106} 107 108void 109set(::sc_core::sc_time *time, double d, ::sc_core::sc_time_unit tu) 110{ 111 if (d != 0) 112 attemptToFixTime(); 113 if (pythonReady) { 114 // Time should be working. Set up this sc_time. 115 setWork(time, d, tu); 116 } else { 117 // Time isn't set up yet. Defer setting up this sc_time. 118 toSet.emplace_back(time, d, tu); 119 } 120} 121 122class TimeSetter : public ::sc_gem5::PythonReadyFunc 123{ 124 public: 125 TimeSetter() : ::sc_gem5::PythonReadyFunc() {} 126 127 void 128 run() override 129 { 130 // Record that we've run and python/pybind should be usable. 131 pythonReady = true; 132 133 // If time is already fixed, let python know. 134 if (timeFixed) 135 fixTime(); 136 } 137} timeSetter; 138 139double defaultUnit = 1.0e-9; 140 141} // anonymous namespace 142 143sc_time::sc_time() : val(0) {} 144 145sc_time::sc_time(double d, sc_time_unit tu) 146{ 147 val = 0; 148 set(this, d, tu); 149} 150 151sc_time::sc_time(const sc_time &t) 152{ 153 val = t.val; 154} 155 156sc_time::sc_time(double d, bool scale) 157{ 158 double scaler = scale ? defaultUnit : SimClock::Float::Hz; 159 set(this, d * scaler, SC_SEC); 160} 161 162sc_time::sc_time(sc_dt::uint64 v, bool scale) 163{ 164 double scaler = scale ? defaultUnit : SimClock::Float::Hz; 165 set(this, static_cast<double>(v) * scaler, SC_SEC); 166} 167 168sc_time & 169sc_time::operator = (const sc_time &t) 170{ 171 val = t.val; 172 return *this; 173} 174 175sc_dt::uint64 176sc_time::value() const 177{ 178 return val; 179} 180 181double 182sc_time::to_double() const 183{ 184 return static_cast<double>(val); 185} 186double 187sc_time::to_seconds() const 188{ 189 return to_double() * SimClock::Float::Hz; 190} 191 192const std::string 193sc_time::to_string() const 194{ 195 std::ostringstream ss; 196 print(ss); 197 return ss.str(); 198} 199 200bool 201sc_time::operator == (const sc_time &t) const 202{ 203 return val == t.val; 204} 205 206bool 207sc_time::operator != (const sc_time &t) const 208{ 209 return val != t.val; 210} 211 212bool 213sc_time::operator < (const sc_time &t) const 214{ 215 return val < t.val; 216} 217 218bool 219sc_time::operator <= (const sc_time &t) const 220{ 221 return val <= t.val; 222} 223 224bool 225sc_time::operator > (const sc_time &t) const 226{ 227 return val > t.val; 228} 229 230bool 231sc_time::operator >= (const sc_time &t) const 232{ 233 return val >= t.val; 234} 235 236sc_time & 237sc_time::operator += (const sc_time &t) 238{ 239 val += t.val; 240 return *this; 241} 242 243sc_time & 244sc_time::operator -= (const sc_time &t) 245{ 246 val -= t.val; 247 return *this; 248} 249 250sc_time & 251sc_time::operator *= (double d) 252{ 253 val = static_cast<int64_t>(static_cast<double>(val) * d + 0.5); 254 return *this; 255} 256 257sc_time & 258sc_time::operator /= (double d) 259{ 260 val = static_cast<int64_t>(static_cast<double>(val) / d + 0.5); 261 return *this; 262} 263 264void 265sc_time::print(std::ostream &os) const 266{ 267 if (val == 0) { 268 os << "0 s"; 269 } else { 270 Tick frequency = SimClock::Frequency; 271 272 // Shrink the frequency by scaling down the time period, ie converting 273 // it from cycles per second to cycles per millisecond, etc. 274 sc_time_unit tu = SC_SEC; 275 while (tu > 1 && (frequency % 1000 == 0)) { 276 tu = (sc_time_unit)((int)tu - 1); 277 frequency /= 1000; 278 } 279 280 // Convert the frequency into a period. 281 Tick period; 282 if (frequency > 1) { 283 tu = (sc_time_unit)((int)tu - 1); 284 period = 1000 / frequency; 285 } else { 286 period = frequency; 287 } 288 289 // Scale our integer value by the period. 290 uint64_t scaled = val * period; 291 292 // Shrink the scaled time value by increasing the size of the units 293 // it's measured by, avoiding fractional parts. 294 while (tu < SC_SEC && (scaled % 1000) == 0) { 295 tu = (sc_time_unit)((int)tu + 1); 296 scaled /= 1000; 297 } 298 299 os << scaled << ' ' << sc_gem5::TimeUnitNames[tu]; 300 } 301} 302 303sc_time 304sc_time::from_value(sc_dt::uint64 u) 305{ 306 if (u) 307 attemptToFixTime(); 308 sc_time t; 309 t.val = u; 310 return t; 311} 312 313sc_time 314sc_time::from_seconds(double d) 315{ 316 sc_time t; 317 set(&t, d, SC_SEC); 318 return t; 319} 320 321sc_time 322sc_time::from_string(const char *str) 323{ 324 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 325 return sc_time(); 326} 327 328const sc_time 329operator + (const sc_time &a, const sc_time &b) 330{ 331 return sc_time::from_value(a.value() + b.value()); 332} 333 334const sc_time 335operator - (const sc_time &a, const sc_time &b) 336{ 337 return sc_time::from_value(a.value() - b.value()); 338} 339 340const sc_time 341operator * (const sc_time &t, double d) 342{ 343 volatile double tmp = static_cast<double>(t.value()) * d + 0.5; 344 return sc_time::from_value(static_cast<int64_t>(tmp)); 345} 346 347const sc_time 348operator * (double d, const sc_time &t) 349{ 350 volatile double tmp = d * static_cast<double>(t.value()) + 0.5; 351 return sc_time::from_value(static_cast<int64_t>(tmp)); 352} 353 354const sc_time 355operator / (const sc_time &t, double d) 356{ 357 volatile double tmp = static_cast<double>(t.value()) / d + 0.5; 358 return sc_time::from_value(static_cast<int64_t>(tmp)); 359} 360 361double 362operator / (const sc_time &t1, const sc_time &t2) 363{ 364 return t1.to_double() / t2.to_double(); 365} 366 367std::ostream & 368operator << (std::ostream &os, const sc_time &t) 369{ 370 t.print(os); 371 return os; 372} 373 374const sc_time SC_ZERO_TIME; 375 376void 377sc_set_time_resolution(double d, sc_time_unit tu) 378{ 379 if (d <= 0.0) { 380 SC_REPORT_ERROR("(E514) set time resolution failed", 381 "value not positive"); 382 } 383 double dummy; 384 if (modf(log10(d), &dummy) != 0.0) { 385 SC_REPORT_ERROR("(E514) set time resolution failed", 386 "value not a power of ten"); 387 } 388 if (sc_is_running()) { 389 SC_REPORT_ERROR("(E514) set time resolution failed", 390 "simulation running"); 391 } 392 static bool specified = false; 393 if (specified) { 394 SC_REPORT_ERROR("(E514) set time resolution failed", 395 "already specified"); 396 } 397 // This won't detect the timescale being fixed outside of systemc, but 398 // it's at least some protection. 399 if (timeFixed) { 400 SC_REPORT_ERROR("(E514) set time resolution failed", 401 "sc_time object(s) constructed"); 402 } 403 404 double seconds = d * sc_gem5::TimeUnitScale[tu]; 405 if (seconds < sc_gem5::TimeUnitScale[SC_FS]) { 406 SC_REPORT_ERROR("(E514) set time resolution failed", 407 "value smaller than 1 fs"); 408 } 409 410 if (seconds > defaultUnit) { 411 SC_REPORT_WARNING( 412 "(W516) default time unit changed to time resolution", ""); 413 defaultUnit = seconds; 414 } 415 416 // Get rid of fractional parts of d. 417 while (d < 1.0 && tu > SC_FS) { 418 d *= 1000; 419 tu = (sc_time_unit)(tu - 1); 420 } 421 422 Tick ticks_per_second = 423 sc_gem5::TimeUnitFrequency[tu] / static_cast<Tick>(d); 424 setGlobalFrequency(ticks_per_second); 425 specified = true; 426} 427 428sc_time 429sc_get_time_resolution() 430{ 431 return sc_time::from_value(1); 432} 433 434const sc_time & 435sc_max_time() 436{ 437 static const sc_time MaxScTime = sc_time::from_value(MaxTick); 438 return MaxScTime; 439} 440 441void 442sc_set_default_time_unit(double d, sc_time_unit tu) 443{ 444 if (d < 0.0) { 445 SC_REPORT_ERROR("(E515) set default time unit failed", 446 "value not positive"); 447 } 448 double dummy; 449 if (modf(log10(d), &dummy) != 0.0) { 450 SC_REPORT_ERROR("(E515) set default time unit failed", 451 "value not a power of ten"); 452 } 453 if (sc_is_running()) { 454 SC_REPORT_ERROR("(E515) set default time unit failed", 455 "simulation running"); 456 } 457 static bool specified = false; 458 if (specified) { 459 SC_REPORT_ERROR("(E515) set default time unit failed", 460 "already specified"); 461 } 462 // This won't detect the timescale being fixed outside of systemc, but 463 // it's at least some protection. 464 if (timeFixed) { 465 SC_REPORT_ERROR("(E515) set default time unit failed", 466 "sc_time object(s) constructed"); 467 } 468 469 // Normalize d to seconds. 470 defaultUnit = d * sc_gem5::TimeUnitScale[tu]; 471 specified = true; 472 473 double resolution = SimClock::Float::Hz; 474 if (resolution == 0.0) 475 resolution = sc_gem5::TimeUnitScale[SC_PS]; 476 if (defaultUnit < resolution) { 477 SC_REPORT_ERROR("(E515) set default time unit failed", 478 "value smaller than time resolution"); 479 } 480} 481 482sc_time 483sc_get_default_time_unit() 484{ 485 return sc_time(defaultUnit, SC_SEC); 486} 487 488sc_time_tuple::sc_time_tuple(const sc_time &) 489{ 490 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 491} 492 493bool 494sc_time_tuple::has_value() const 495{ 496 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 497 return false; 498} 499 500sc_dt::uint64 501sc_time_tuple::value() const 502{ 503 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 504 return 0; 505} 506 507const char * 508sc_time_tuple::unit_symbol() const 509{ 510 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 511 return ""; 512} 513 514double 515sc_time_tuple::to_double() const 516{ 517 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 518 return 0.0; 519} 520 521std::string 522sc_time_tuple::to_string() const 523{ 524 warn("%s not implemented.\n", __PRETTY_FUNCTION__); 525 return ""; 526} 527 528} // namespace sc_core 529