sc_time.cc revision 13265
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, const char *unit) 157{ 158 sc_time_unit tu; 159 for (tu = SC_FS; tu <= SC_SEC; tu = (sc_time_unit)(tu + 1)) { 160 if (strcmp(unit, sc_gem5::TimeUnitNames[tu]) == 0 || 161 strcmp(unit, sc_gem5::TimeUnitConstantNames[tu]) == 0) { 162 break; 163 } 164 } 165 166 if (tu > SC_SEC) { 167 SC_REPORT_ERROR("(E567) sc_time conversion failed", 168 "invalid unit given"); 169 val = 0; 170 return; 171 } 172 set(this, d, tu); 173} 174 175sc_time::sc_time(double d, bool scale) 176{ 177 double scaler = scale ? defaultUnit : SimClock::Float::Hz; 178 set(this, d * scaler, SC_SEC); 179} 180 181sc_time::sc_time(sc_dt::uint64 v, bool scale) 182{ 183 double scaler = scale ? defaultUnit : SimClock::Float::Hz; 184 set(this, static_cast<double>(v) * scaler, SC_SEC); 185} 186 187sc_time & 188sc_time::operator = (const sc_time &t) 189{ 190 val = t.val; 191 return *this; 192} 193 194sc_dt::uint64 195sc_time::value() const 196{ 197 return val; 198} 199 200double 201sc_time::to_double() const 202{ 203 return static_cast<double>(val); 204} 205double 206sc_time::to_seconds() const 207{ 208 return to_double() * SimClock::Float::Hz; 209} 210 211const std::string 212sc_time::to_string() const 213{ 214 std::ostringstream ss; 215 print(ss); 216 return ss.str(); 217} 218 219bool 220sc_time::operator == (const sc_time &t) const 221{ 222 return val == t.val; 223} 224 225bool 226sc_time::operator != (const sc_time &t) const 227{ 228 return val != t.val; 229} 230 231bool 232sc_time::operator < (const sc_time &t) const 233{ 234 return val < t.val; 235} 236 237bool 238sc_time::operator <= (const sc_time &t) const 239{ 240 return val <= t.val; 241} 242 243bool 244sc_time::operator > (const sc_time &t) const 245{ 246 return val > t.val; 247} 248 249bool 250sc_time::operator >= (const sc_time &t) const 251{ 252 return val >= t.val; 253} 254 255sc_time & 256sc_time::operator += (const sc_time &t) 257{ 258 val += t.val; 259 return *this; 260} 261 262sc_time & 263sc_time::operator -= (const sc_time &t) 264{ 265 val -= t.val; 266 return *this; 267} 268 269sc_time & 270sc_time::operator *= (double d) 271{ 272 val = static_cast<int64_t>(static_cast<double>(val) * d + 0.5); 273 return *this; 274} 275 276sc_time & 277sc_time::operator /= (double d) 278{ 279 val = static_cast<int64_t>(static_cast<double>(val) / d + 0.5); 280 return *this; 281} 282 283void 284sc_time::print(std::ostream &os) const 285{ 286 os << sc_time_tuple(*this).to_string(); 287} 288 289sc_time 290sc_time::from_value(sc_dt::uint64 u) 291{ 292 if (u) 293 attemptToFixTime(); 294 sc_time t; 295 t.val = u; 296 return t; 297} 298 299sc_time 300sc_time::from_seconds(double d) 301{ 302 sc_time t; 303 set(&t, d, SC_SEC); 304 return t; 305} 306 307sc_time 308sc_time::from_string(const char *str) 309{ 310 char *end = nullptr; 311 312 double d = str ? std::strtod(str, &end) : 0.0; 313 if (str == end || d < 0.0) { 314 SC_REPORT_ERROR("(E567) sc_time conversion failed", 315 "invalid value given"); 316 return SC_ZERO_TIME; 317 } 318 319 while (*end && std::isspace(*end)) 320 end++; 321 322 return sc_time(d, end); 323} 324 325const sc_time 326operator + (const sc_time &a, const sc_time &b) 327{ 328 return sc_time::from_value(a.value() + b.value()); 329} 330 331const sc_time 332operator - (const sc_time &a, const sc_time &b) 333{ 334 return sc_time::from_value(a.value() - b.value()); 335} 336 337const sc_time 338operator * (const sc_time &t, double d) 339{ 340 volatile double tmp = static_cast<double>(t.value()) * d + 0.5; 341 return sc_time::from_value(static_cast<int64_t>(tmp)); 342} 343 344const sc_time 345operator * (double d, const sc_time &t) 346{ 347 volatile double tmp = d * static_cast<double>(t.value()) + 0.5; 348 return sc_time::from_value(static_cast<int64_t>(tmp)); 349} 350 351const sc_time 352operator / (const sc_time &t, double d) 353{ 354 volatile double tmp = static_cast<double>(t.value()) / d + 0.5; 355 return sc_time::from_value(static_cast<int64_t>(tmp)); 356} 357 358double 359operator / (const sc_time &t1, const sc_time &t2) 360{ 361 return t1.to_double() / t2.to_double(); 362} 363 364std::ostream & 365operator << (std::ostream &os, const sc_time &t) 366{ 367 t.print(os); 368 return os; 369} 370 371const sc_time SC_ZERO_TIME; 372 373void 374sc_set_time_resolution(double d, sc_time_unit tu) 375{ 376 if (d <= 0.0) { 377 SC_REPORT_ERROR("(E514) set time resolution failed", 378 "value not positive"); 379 } 380 double dummy; 381 if (modf(log10(d), &dummy) != 0.0) { 382 SC_REPORT_ERROR("(E514) set time resolution failed", 383 "value not a power of ten"); 384 } 385 if (sc_is_running()) { 386 SC_REPORT_ERROR("(E514) set time resolution failed", 387 "simulation running"); 388 } 389 static bool specified = false; 390 if (specified) { 391 SC_REPORT_ERROR("(E514) set time resolution failed", 392 "already specified"); 393 } 394 // This won't detect the timescale being fixed outside of systemc, but 395 // it's at least some protection. 396 if (timeFixed) { 397 SC_REPORT_ERROR("(E514) set time resolution failed", 398 "sc_time object(s) constructed"); 399 } 400 401 double seconds = d * sc_gem5::TimeUnitScale[tu]; 402 if (seconds < sc_gem5::TimeUnitScale[SC_FS]) { 403 SC_REPORT_ERROR("(E514) set time resolution failed", 404 "value smaller than 1 fs"); 405 } 406 407 if (seconds > defaultUnit) { 408 SC_REPORT_WARNING( 409 "(W516) default time unit changed to time resolution", ""); 410 defaultUnit = seconds; 411 } 412 413 // Get rid of fractional parts of d. 414 while (d < 1.0 && tu > SC_FS) { 415 d *= 1000; 416 tu = (sc_time_unit)(tu - 1); 417 } 418 419 Tick ticks_per_second = 420 sc_gem5::TimeUnitFrequency[tu] / static_cast<Tick>(d); 421 setGlobalFrequency(ticks_per_second); 422 specified = true; 423} 424 425sc_time 426sc_get_time_resolution() 427{ 428 return sc_time::from_value(1); 429} 430 431const sc_time & 432sc_max_time() 433{ 434 static const sc_time MaxScTime = sc_time::from_value(MaxTick); 435 return MaxScTime; 436} 437 438void 439sc_set_default_time_unit(double d, sc_time_unit tu) 440{ 441 if (d < 0.0) { 442 SC_REPORT_ERROR("(E515) set default time unit failed", 443 "value not positive"); 444 } 445 double dummy; 446 if (modf(log10(d), &dummy) != 0.0) { 447 SC_REPORT_ERROR("(E515) set default time unit failed", 448 "value not a power of ten"); 449 } 450 if (sc_is_running()) { 451 SC_REPORT_ERROR("(E515) set default time unit failed", 452 "simulation running"); 453 } 454 static bool specified = false; 455 if (specified) { 456 SC_REPORT_ERROR("(E515) set default time unit failed", 457 "already specified"); 458 } 459 // This won't detect the timescale being fixed outside of systemc, but 460 // it's at least some protection. 461 if (timeFixed) { 462 SC_REPORT_ERROR("(E515) set default time unit failed", 463 "sc_time object(s) constructed"); 464 } 465 466 // Normalize d to seconds. 467 defaultUnit = d * sc_gem5::TimeUnitScale[tu]; 468 specified = true; 469 470 double resolution = SimClock::Float::Hz; 471 if (resolution == 0.0) 472 resolution = sc_gem5::TimeUnitScale[SC_PS]; 473 if (defaultUnit < resolution) { 474 SC_REPORT_ERROR("(E515) set default time unit failed", 475 "value smaller than time resolution"); 476 } 477} 478 479sc_time 480sc_get_default_time_unit() 481{ 482 return sc_time(defaultUnit, SC_SEC); 483} 484 485sc_time_tuple::sc_time_tuple(const sc_time &t) : 486 _value(), _unit(SC_SEC), _set(true) 487{ 488 if (!t.value()) 489 return; 490 491 Tick frequency = SimClock::Frequency; 492 493 // Shrink the frequency by scaling down the time period, ie converting 494 // it from cycles per second to cycles per millisecond, etc. 495 while (_unit > 1 && (frequency % 1000 == 0)) { 496 _unit = (sc_time_unit)((int)_unit - 1); 497 frequency /= 1000; 498 } 499 500 // Convert the frequency into a period. 501 Tick period; 502 if (frequency > 1) { 503 _unit = (sc_time_unit)((int)_unit - 1); 504 period = 1000 / frequency; 505 } else { 506 period = frequency; 507 } 508 509 // Scale our integer value by the period. 510 _value = t.value() * period; 511 512 // Shrink the scaled time value by increasing the size of the units 513 // it's measured by, avoiding fractional parts. 514 while (_unit < SC_SEC && (_value % 1000) == 0) { 515 _unit = (sc_time_unit)((int)_unit + 1); 516 _value /= 1000; 517 } 518} 519 520bool 521sc_time_tuple::has_value() const 522{ 523 return _set; 524} 525 526sc_dt::uint64 sc_time_tuple::value() const { return _value; } 527 528const char * 529sc_time_tuple::unit_symbol() const 530{ 531 return sc_gem5::TimeUnitNames[_unit]; 532} 533 534double sc_time_tuple::to_double() const { return static_cast<double>(_value); } 535 536std::string 537sc_time_tuple::to_string() const 538{ 539 std::ostringstream ss; 540 ss << _value << ' ' << unit_symbol(); 541 return ss.str(); 542} 543 544} // namespace sc_core 545