sc_time.cc revision 13057:b1cdffff3bed 
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 <vector>
31
32#include "base/logging.hh"
33#include "base/types.hh"
34#include "python/pybind11/pybind.hh"
35#include "systemc/core/python.hh"
36#include "systemc/ext/core/sc_time.hh"
37
38namespace sc_core
39{
40
41namespace
42{
43
44const char *TimeUnitNames[] = {
45    [SC_FS] = "fs",
46    [SC_PS] = "ps",
47    [SC_NS] = "ns",
48    [SC_US] = "us",
49    [SC_MS] = "ms",
50    [SC_SEC] = "s"
51};
52
53double TimeUnitScale[] = {
54    [SC_FS] = 1.0e-15,
55    [SC_PS] = 1.0e-12,
56    [SC_NS] = 1.0e-9,
57    [SC_US] = 1.0e-6,
58    [SC_MS] = 1.0e-3,
59    [SC_SEC] = 1.0
60};
61
62bool timeFixed = false;
63bool pythonReady = false;
64
65struct SetInfo
66{
67    SetInfo(::sc_core::sc_time *time, double d, ::sc_core::sc_time_unit tu) :
68        time(time), d(d), tu(tu)
69    {}
70
71    ::sc_core::sc_time *time;
72    double d;
73    ::sc_core::sc_time_unit tu;
74};
75std::vector<SetInfo> toSet;
76
77void
78setWork(sc_time *time, double d, ::sc_core::sc_time_unit tu)
79{
80    //XXX Assuming the time resolution is 1ps.
81    double scale = TimeUnitScale[tu] / TimeUnitScale[SC_PS];
82    // Accellera claims there is a linux bug, and that these next two
83    // lines work around them.
84    volatile double tmp = d * scale + 0.5;
85    *time = sc_time::from_value(static_cast<uint64_t>(tmp));
86}
87
88void
89fixTime()
90{
91    auto ticks = pybind11::module::import("m5.ticks");
92    auto fix_global_frequency = ticks.attr("fixGlobalFrequency");
93    fix_global_frequency();
94
95    for (auto &t: toSet)
96        setWork(t.time, t.d, t.tu);
97    toSet.clear();
98}
99
100void
101set(::sc_core::sc_time *time, double d, ::sc_core::sc_time_unit tu)
102{
103    // Only fix time once.
104    if (!timeFixed) {
105        timeFixed = true;
106
107        // If we've run, python is working and we haven't fixed time yet.
108        if (pythonReady)
109            fixTime();
110    }
111    if (pythonReady) {
112        // Time should be working. Set up this sc_time.
113        setWork(time, d, tu);
114    } else {
115        // Time isn't set up yet. Defer setting up this sc_time.
116        toSet.emplace_back(time, d, tu);
117    }
118}
119
120class TimeSetter : public ::sc_gem5::PythonReadyFunc
121{
122  public:
123    TimeSetter() : ::sc_gem5::PythonReadyFunc() {}
124
125    void
126    run() override
127    {
128        // Record that we've run and python/pybind should be usable.
129        pythonReady = true;
130
131        // If time is already fixed, let python know.
132        if (timeFixed)
133            fixTime();
134    }
135} timeSetter;
136
137} // anonymous namespace
138
139sc_time::sc_time() : val(0) {}
140
141sc_time::sc_time(double d, sc_time_unit tu)
142{
143    val = 0;
144    if (d != 0)
145        set(this, d, tu);
146}
147
148sc_time::sc_time(const sc_time &t)
149{
150    val = t.val;
151}
152
153sc_time::sc_time(double d, bool scale)
154{
155    //XXX Assuming the time resolution is 1ps, and the default unit is 1ns.
156    set(this, d, scale ? SC_NS : SC_PS);
157}
158
159sc_time::sc_time(sc_dt::uint64 v, bool scale)
160{
161    //XXX Assuming the time resolution is 1ps, and the default unit is 1ns.
162    set(this, static_cast<double>(v), scale ? SC_NS : SC_PS);
163}
164
165sc_time &
166sc_time::operator = (const sc_time &t)
167{
168    val = t.val;
169    return *this;
170}
171
172sc_dt::uint64
173sc_time::value() const
174{
175    return val;
176}
177
178double
179sc_time::to_double() const
180{
181    return static_cast<double>(val);
182}
183double
184sc_time::to_seconds() const
185{
186    double d = to_double();
187    //XXX Assuming the time resolution is 1ps.
188    double scale = TimeUnitScale[SC_PS] / TimeUnitScale[SC_SEC];
189    return d * scale;
190}
191
192const std::string
193sc_time::to_string() const
194{
195    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
196    return "";
197}
198
199bool
200sc_time::operator == (const sc_time &t) const
201{
202    return val == t.val;
203}
204
205bool
206sc_time::operator != (const sc_time &t) const
207{
208    return val != t.val;
209}
210
211bool
212sc_time::operator < (const sc_time &t) const
213{
214    return val < t.val;
215}
216
217bool
218sc_time::operator <= (const sc_time &t) const
219{
220    return val <= t.val;
221}
222
223bool
224sc_time::operator > (const sc_time &t) const
225{
226    return val > t.val;
227}
228
229bool
230sc_time::operator >= (const sc_time &t) const
231{
232    return val >= t.val;
233}
234
235sc_time &
236sc_time::operator += (const sc_time &t)
237{
238    val += t.val;
239    return *this;
240}
241
242sc_time &
243sc_time::operator -= (const sc_time &t)
244{
245    val -= t.val;
246    return *this;
247}
248
249sc_time &
250sc_time::operator *= (double d)
251{
252    val = static_cast<int64_t>(static_cast<double>(val) * d + 0.5);
253    return *this;
254}
255
256sc_time &
257sc_time::operator /= (double d)
258{
259    val = static_cast<int64_t>(static_cast<double>(val) / d + 0.5);
260    return *this;
261}
262
263void
264sc_time::print(std::ostream &os) const
265{
266    if (val == 0) {
267        os << "0 s";
268    } else {
269        //XXX Assuming the time resolution is 1ps.
270        sc_time_unit tu = SC_PS;
271        uint64_t scaled = val;
272        while (tu < SC_SEC && (scaled % 1000) == 0) {
273            tu = (sc_time_unit)((int)tu + 1);
274            scaled /= 1000;
275        }
276
277        os << scaled << ' ' << TimeUnitNames[tu];
278    }
279}
280
281sc_time
282sc_time::from_value(sc_dt::uint64 u)
283{
284    sc_time t;
285    t.val = u;
286    return t;
287}
288
289sc_time
290sc_time::from_seconds(double d)
291{
292    sc_time t;
293    set(&t, d, SC_SEC);
294    return t;
295}
296
297sc_time
298sc_time::from_string(const char *str)
299{
300    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
301    return sc_time();
302}
303
304const sc_time
305operator + (const sc_time &a, const sc_time &b)
306{
307    return sc_time::from_value(a.value() + b.value());
308}
309
310const sc_time
311operator - (const sc_time &a, const sc_time &b)
312{
313    return sc_time::from_value(a.value() - b.value());
314}
315
316const sc_time
317operator * (const sc_time &t, double d)
318{
319    volatile double tmp = static_cast<double>(t.value()) * d + 0.5;
320    return sc_time::from_value(static_cast<int64_t>(tmp));
321}
322
323const sc_time
324operator * (double d, const sc_time &t)
325{
326    volatile double tmp = d * static_cast<double>(t.value()) + 0.5;
327    return sc_time::from_value(static_cast<int64_t>(tmp));
328}
329
330const sc_time
331operator / (const sc_time &t, double d)
332{
333    volatile double tmp = static_cast<double>(t.value()) / d + 0.5;
334    return sc_time::from_value(static_cast<int64_t>(tmp));
335}
336
337double
338operator / (const sc_time &t1, const sc_time &t2)
339{
340    return t1.to_double() / t2.to_double();
341}
342
343std::ostream &
344operator << (std::ostream &os, const sc_time &t)
345{
346    t.print(os);
347    return os;
348}
349
350const sc_time SC_ZERO_TIME;
351
352void
353sc_set_time_resolution(double, sc_time_unit)
354{
355    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
356}
357
358sc_time
359sc_get_time_resolution()
360{
361    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
362    return sc_time();
363}
364
365const sc_time &
366sc_max_time()
367{
368    static const sc_time MaxScTime = sc_time::from_value(MaxTick);
369    return MaxScTime;
370}
371
372void
373sc_set_default_time_unit(double, sc_time_unit)
374{
375    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
376}
377
378sc_time
379sc_get_default_time_unit()
380{
381    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
382    return *(sc_time *)nullptr;
383}
384
385sc_time_tuple::sc_time_tuple(const sc_time &)
386{
387    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
388}
389
390bool
391sc_time_tuple::has_value() const
392{
393    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
394    return false;
395}
396
397sc_dt::uint64
398sc_time_tuple::value() const
399{
400    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
401    return 0;
402}
403
404const char *
405sc_time_tuple::unit_symbol() const
406{
407    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
408    return "";
409}
410
411double
412sc_time_tuple::to_double() const
413{
414    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
415    return 0.0;
416}
417
418std::string
419sc_time_tuple::to_string() const
420{
421    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
422    return "";
423}
424
425} // namespace sc_core
426