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authorAli Saidi <saidi@eecs.umich.edu>2007-10-31 01:21:54 -0400
committerAli Saidi <saidi@eecs.umich.edu>2007-10-31 01:21:54 -0400
commit7597f87430bc25547c594dd09f10be4953f987c3 (patch)
treef1016e3df49d93020b8d2e0931872e17696a7bca /src
parent04d1cfe31ce92809830722081f3223a4d61b05df (diff)
downloadgem5-7597f87430bc25547c594dd09f10be4953f987c3.tar.xz
Base: Rework the way M5 provides and creates random numbers.
--HG-- extra : convert_revision : 10ec3484647b3acb8e821f8520f97d535e41e861
Diffstat (limited to 'src')
-rw-r--r--src/base/SConscript1
-rw-r--r--src/base/random.cc98
-rw-r--r--src/base/random.hh288
-rw-r--r--src/base/random_mt.cc149
-rw-r--r--src/dev/etherlink.cc7
5 files changed, 416 insertions, 127 deletions
diff --git a/src/base/SConscript b/src/base/SConscript
index ca68bfb60..393cf57ec 100644
--- a/src/base/SConscript
+++ b/src/base/SConscript
@@ -70,6 +70,7 @@ Source('misc.cc')
Source('output.cc')
Source('pollevent.cc')
Source('random.cc')
+Source('random_mt.cc')
Source('range.cc')
Source('remote_gdb.cc')
Source('sat_counter.cc')
diff --git a/src/base/random.cc b/src/base/random.cc
index 8a2e3c1c0..7daa90b9c 100644
--- a/src/base/random.cc
+++ b/src/base/random.cc
@@ -29,60 +29,88 @@
* Ali Saidi
*/
-#ifdef __SUNPRO_CC
-#include <stdlib.h>
-#include <math.h>
-#endif
-
-#include <cstdlib>
-#include <cmath>
-
#include "base/fenv.hh"
+#include "base/intmath.hh"
+#include "base/misc.hh"
#include "base/random.hh"
+#include "sim/serialize.hh"
using namespace std;
-uint32_t
-getInt32()
+Random::Random()
{
- return mrand48() & 0xffffffff;
+ // default random seed taken from original source
+ init(5489);
}
-double
-getDouble()
+Random::Random(uint32_t s)
{
- return drand48();
+ init(s);
}
-double
-m5round(double r)
+Random::Random(uint32_t init_key[], int key_length)
{
-#if defined(__sun)
- double val;
- int oldrnd = m5_fegetround();
- m5_fesetround(M5_FE_TONEAREST);
- val = rint(r);
- m5_fesetround(oldrnd);
- return val;
-#else
- return round(r);
-#endif
+ init(init_key, key_length);
}
-int64_t
-getUniform(int64_t min, int64_t max)
+Random::~Random()
{
- double r;
- r = drand48() * (max-min) + min;
+}
- return (int64_t)m5round(r);
+// To preserve the uniform random distribution between min and max,
+// and allow all numbers to be represented, we generate a uniform
+// random number to the nearest power of two greater than max. If
+// this number doesn't fall between 0 and max, we try again. Anything
+// else would skew the distribution.
+uint32_t
+Random::genrand(uint32_t max)
+{
+ int log = ceilLog2(max);
+ int shift = (sizeof(uint32_t) * 8 - log);
+ uint32_t random;
+
+ do {
+ random = genrand() >> shift;
+ } while (random > max);
+
+ return random;
}
uint64_t
-getUniformPos(uint64_t min, uint64_t max)
+Random::genrand(uint64_t max)
+{
+ int log = ceilLog2(max);
+ int shift = (sizeof(uint64_t) * 8 - log);
+ uint64_t random;
+
+ do {
+ random = (uint64_t)genrand() << 32 | (uint64_t)genrand();
+ random = random >> shift;
+ } while (random > max);
+
+ return random;
+}
+
+void
+Random::serialize(const string &base, ostream &os)
{
- double r;
- r = drand48() * (max-min) + min;
+ int length = N;
+ paramOut(os, base + ".mti", mti);
+ paramOut(os, base + ".length", length);
+ arrayParamOut(os, base + ".data", mt, length);
+}
- return (uint64_t)m5round(r);
+void
+Random::unserialize(const string &base, Checkpoint *cp, const string &section)
+{
+ int length;
+
+ paramIn(cp, section, base + ".mti", mti);
+ paramIn(cp, section, base + ".length", length);
+ if (length != N)
+ panic("cant unserialize random number data. length != %d\n", length);
+
+ arrayParamIn(cp, section, base + ".data", mt, length);
}
+
+Random random_mt;
diff --git a/src/base/random.hh b/src/base/random.hh
index 0cd88728d..401ba086f 100644
--- a/src/base/random.hh
+++ b/src/base/random.hh
@@ -32,99 +32,211 @@
#ifndef __BASE_RANDOM_HH__
#define __BASE_RANDOM_HH__
-#include "sim/host.hh"
-
-uint32_t getUInt32();
-double getDouble();
-double m5random(double r);
-uint64_t getUniformPos(uint64_t min, uint64_t max);
-int64_t getUniform(int64_t min, int64_t max);
-
-template <typename T>
-struct Random;
-
-template<> struct Random<int8_t>
-{
- static int8_t get()
- { return getUInt32() & (int8_t)-1; }
-
- static int8_t uniform(int8_t min, int8_t max)
- { return getUniform(min, max); }
-};
-
-template<> struct Random<uint8_t>
-{
- static uint8_t get()
- { return getUInt32() & (uint8_t)-1; }
-
- static uint8_t uniform(uint8_t min, uint8_t max)
- { return getUniformPos(min, max); }
-};
-
-template<> struct Random<int16_t>
-{
- static int16_t get()
- { return getUInt32() & (int16_t)-1; }
-
- static int16_t uniform(int16_t min, int16_t max)
- { return getUniform(min, max); }
-};
-
-template<> struct Random<uint16_t>
-{
- static uint16_t get()
- { return getUInt32() & (uint16_t)-1; }
-
- static uint16_t uniform(uint16_t min, uint16_t max)
- { return getUniformPos(min, max); }
-};
-
-template<> struct Random<int32_t>
-{
- static int32_t get()
- { return (int32_t)getUInt32(); }
-
- static int32_t uniform(int32_t min, int32_t max)
- { return getUniform(min, max); }
-};
-
-template<> struct Random<uint32_t>
-{
- static uint32_t get()
- { return (uint32_t)getUInt32(); }
-
- static uint32_t uniform(uint32_t min, uint32_t max)
- { return getUniformPos(min, max); }
-};
+#include <ios>
+#include <string>
-template<> struct Random<int64_t>
-{
- static int64_t get()
- { return (int64_t)getUInt32() << 32 || (uint64_t)getUInt32(); }
-
- static int64_t uniform(int64_t min, int64_t max)
- { return getUniform(min, max); }
-};
-
-template<> struct Random<uint64_t>
-{
- static uint64_t get()
- { return (uint64_t)getUInt32() << 32 || (uint64_t)getUInt32(); }
+#include "base/range.hh"
+#include "sim/host.hh"
- static uint64_t uniform(uint64_t min, uint64_t max)
- { return getUniformPos(min, max); }
-};
+class Checkpoint;
-template<> struct Random<float>
+class Random
{
- static float get()
- { return getDouble(); }
+ protected:
+ static const int N = 624;
+ static const int M = 397;
+ static const uint32_t MATRIX_A = (uint32_t)0x9908b0df;
+ static const uint32_t UPPER_MASK = (uint32_t)0x80000000;
+ static const uint32_t LOWER_MASK = (uint32_t)0x7fffffff;
+
+ uint32_t mt[N];
+ int mti;
+
+ uint32_t genrand();
+ uint32_t genrand(uint32_t max);
+ uint64_t genrand(uint64_t max);
+
+ void
+ _random(int8_t &value)
+ {
+ value = genrand() & (int8_t)-1;
+ }
+
+ void
+ _random(int16_t &value)
+ {
+ value = genrand() & (int16_t)-1;
+ }
+
+ void
+ _random(int32_t &value)
+ {
+ value = (int32_t)genrand();
+ }
+
+ void
+ _random(int64_t &value)
+ {
+ value = (int64_t)genrand() << 32 | (int64_t)genrand();
+ }
+
+ void
+ _random(uint8_t &value)
+ {
+ value = genrand() & (uint8_t)-1;
+ }
+
+ void
+ _random(uint16_t &value)
+ {
+ value = genrand() & (uint16_t)-1;
+ }
+
+ void
+ _random(uint32_t &value)
+ {
+ value = genrand();
+ }
+
+ void
+ _random(uint64_t &value)
+ {
+ value = (uint64_t)genrand() << 32 | (uint64_t)genrand();
+ }
+
+ // [0,1]
+ void
+ _random(float &value)
+ {
+ // ieee floats have 23 bits of mantissa
+ value = (genrand() >> 9) / 8388608.0;
+ }
+
+ // [0,1]
+ void
+ _random(double &value)
+ {
+ double number = genrand() * 2097152.0 + (genrand() >> 11);
+ value = number / 9007199254740992.0;
+ }
+
+
+ // Range based versions of the random number generator
+ int8_t
+ _random(int8_t min, int8_t max)
+ {
+ uint32_t diff = max - min;
+ return static_cast<int8_t>(min + genrand(diff));
+ }
+
+ int16_t
+ _random(int16_t min, int16_t max)
+ {
+ uint32_t diff = max - min;
+ return static_cast<int16_t>(min + genrand(diff));
+ }
+
+ int32_t
+ _random(int32_t min, int32_t max)
+ {
+ uint32_t diff = max - min;
+ return static_cast<int32_t>(min + genrand(diff));
+ }
+
+ int64_t
+ _random(int64_t min, int64_t max)
+ {
+ uint64_t diff = max - min;
+ return static_cast<int64_t>(min + genrand(diff));
+ }
+
+ uint8_t
+ _random(uint8_t min, uint8_t max)
+ {
+ uint32_t diff = max - min;
+ return static_cast<uint8_t>(min + genrand(diff));
+ }
+
+ uint16_t
+ _random(uint16_t min, uint16_t max)
+ {
+ uint32_t diff = max - min;
+ return static_cast<uint16_t>(min + genrand(diff));
+ }
+
+ uint32_t
+ _random(uint32_t min, uint32_t max)
+ {
+ uint32_t diff = max - min;
+ return static_cast<uint32_t>(min + genrand(diff));
+ }
+
+ uint64_t
+ _random(uint64_t min, uint64_t max)
+ {
+ uint64_t diff = max - min;
+ return static_cast<uint64_t>(min + genrand(diff));
+ }
+
+ public:
+ Random();
+ Random(uint32_t s);
+ Random(uint32_t init_key[], int key_length);
+ ~Random();
+
+ void init(uint32_t s);
+ void init(uint32_t init_key[], int key_length);
+
+ template <typename T>
+ T
+ random()
+ {
+ T value;
+ _random(value);
+ return value;
+ }
+
+ template <typename T>
+ T
+ random(T min, T max)
+ {
+ return _random(min, max);
+ }
+
+ template <typename T>
+ T
+ random(const Range<T> &range)
+ {
+ return _random(range.start, range.end);
+ }
+
+ // [0,1]
+ double
+ gen_real1()
+ {
+ return genrand() / 4294967296.0;
+ }
+
+ // [0,1)
+ double
+ gen_real2()
+ {
+ return genrand() / 4294967295.0;
+ }
+
+ // (0,1)
+ double
+ gen_real3()
+ {
+ return ((double)genrand() + 0.5) / 4294967296.0;
+ }
+
+ public:
+ void serialize(const std::string &base, std::ostream &os);
+ void unserialize(const std::string &base, Checkpoint *cp,
+ const std::string &section);
};
-template<> struct Random<double>
-{
- static double get()
- { return getDouble(); }
-};
+extern Random random_mt;
#endif // __BASE_RANDOM_HH__
diff --git a/src/base/random_mt.cc b/src/base/random_mt.cc
new file mode 100644
index 000000000..1492240ee
--- /dev/null
+++ b/src/base/random_mt.cc
@@ -0,0 +1,149 @@
+/*
+ * A C-program for MT19937, with initialization improved 2002/1/26.
+ * Coded by Takuji Nishimura and Makoto Matsumoto.
+ *
+ * Before using, initialize the state by using init_genrand(seed)
+ * or init_by_array(init_key, key_length).
+ *
+ * Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution.
+ *
+ * 3. The names of its contributors may not be used to endorse or
+ * promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * Any feedback is very welcome.
+ * http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html
+ * email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
+ */
+
+#include "base/random.hh"
+
+/* initializes mt[N] with a seed */
+void
+Random::init(uint32_t s)
+{
+ mti = N + 1;
+ mt[0] = s & (uint32_t)0xffffffff;
+
+ for (mti = 1; mti < N; mti++) {
+ mt[mti] = 1812433253UL * (mt[mti-1] ^ (mt[mti-1] >> 30)) + mti;
+ /* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
+ /* In the previous versions, MSBs of the seed affect */
+ /* only MSBs of the array mt[]. */
+ /* 2002/01/09 modified by Makoto Matsumoto */
+ mt[mti] &= (uint32_t)0xffffffff;
+ /* for >32 bit machines */
+ }
+}
+
+/* initialize by an array with array-length */
+/* init_key is the array for initializing keys */
+/* key_length is its length */
+/* slight change for C++, 2004/2/26 */
+void
+Random::init(uint32_t init_key[], int key_length)
+{
+ int i = 1;
+ int j = 0;
+ int k = (N > key_length) ? N : key_length;
+
+ init(19650218);
+
+ for (; k; k--) {
+ mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * (uint32_t)1664525))
+ + init_key[j] + j; /* non linear */
+
+ mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
+
+ i++;
+ j++;
+
+ if (i >= N) {
+ mt[0] = mt[N - 1];
+ i = 1;
+ }
+
+ if (j >= key_length)
+ j = 0;
+ }
+
+ for (k = N - 1; k; k--) {
+ /* non linear */
+ mt[i] = (mt[i] ^ ((mt[i - 1] ^ (mt[i - 1] >> 30)) * 1566083941UL)) - i;
+
+ /* for WORDSIZE > 32 machines */
+ mt[i] &= (uint32_t)0xffffffff;
+ i++;
+
+ if (i >= N) {
+ mt[0] = mt[N - 1];
+ i = 1;
+ }
+ }
+
+ /* MSB is 1; assuring non-zero initial array */
+ mt[0] = (uint32_t)0x80000000;
+}
+
+/* generates a random number on [0,0xffffffff]-interval */
+uint32_t
+Random::genrand()
+{
+ uint32_t y;
+ static uint32_t mag01[2] = { 0, MATRIX_A};
+
+ if (mti >= N) { /* generate N words at one time */
+ int kk;
+
+ for (kk = 0; kk < N - M; kk++) {
+ y = mt[kk] & UPPER_MASK | mt[kk+1] & LOWER_MASK;
+ mt[kk] = mt[kk + M] ^ (y >> 1) ^ mag01[y & 0x1UL];
+ }
+ for (; kk < N - 1; kk++) {
+ y = mt[kk] & UPPER_MASK | mt[kk+1] & LOWER_MASK;
+ mt[kk] = mt[kk + (M - N)] ^ (y >> 1) ^ mag01[y & 0x1UL];
+ }
+
+ y = mt[N - 1] & UPPER_MASK | mt[0] & LOWER_MASK;
+ mt[N - 1] = mt[M - 1] ^ (y >> 1) ^ mag01[y & 0x1UL];
+
+ mti = 0;
+ }
+
+ y = mt[mti++];
+
+ /* Tempering */
+ y ^= (y >> 11);
+ y ^= (y << 7) & (uint32_t)0x9d2c5680;
+ y ^= (y << 15) & (uint32_t)0xefc60000;
+ y ^= (y >> 18);
+
+ return y;
+}
diff --git a/src/dev/etherlink.cc b/src/dev/etherlink.cc
index 4130a7b3f..b1266000b 100644
--- a/src/dev/etherlink.cc
+++ b/src/dev/etherlink.cc
@@ -177,10 +177,9 @@ EtherLink::Link::transmit(EthPacketPtr pkt)
packet = pkt;
Tick delay = (Tick)ceil(((double)pkt->length * ticksPerByte) + 1.0);
- if (delayVar != 0) {
- Random<Tick> var;
- delay += var.uniform(0, delayVar);
- }
+ if (delayVar != 0)
+ delay += random_mt.random<Tick>(0, delayVar);
+
DPRINTF(Ethernet, "scheduling packet: delay=%d, (rate=%f)\n",
delay, ticksPerByte);
doneEvent.schedule(curTick + delay);