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The BitMachine example is now only built in variants up to 4 bits.

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[SVN r26160]
This commit is contained in:
Andreas Huber
2004-11-09 19:39:39 +00:00
parent 115d8b5237
commit f42b50dad6
2 changed files with 27 additions and 25 deletions
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50
example/BitMachine/BitMachine.cpp
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@@ -7,33 +7,35 @@
//////////////////////////////////////////////////////////////////////////////
const unsigned int noOfBits = 5;
#define CUSTOMIZE_MEMORY_MANAGEMENT
#ifndef NO_OF_BITS
# define NO_OF_BITS 4
#endif
// #define CUSTOMIZE_MEMORY_MANAGEMENT
// #define BOOST_FSM_USE_NATIVE_RTTI
//////////////////////////////////////////////////////////////////////////////
// This program demonstrates the fact that measures must be taken to hide some
// of the complexity (e.g. in separate .cpp file) of a boost::fsm state
// machine once a certain size is reached.
// For this purpose, a state machine with exactly 2^noOfBits states (i.e.
// BitState< 0 > .. BitState< 2^noOfBits - 1 >) is generated. For the events
// EvFlipBit< 0 > .. EvFlipBit< noOfBits - 1 > there is a transition from each
// state to the state with the corresponding bit toggled. That is, there is a
// total of 2^noOfBits * noOfBits transitions.
// For this purpose, a state machine with exactly 2^NO_OF_BITS states (i.e.
// BitState< 0 > .. BitState< 2^NO_OF_BITS - 1 >) is generated. For the events
// EvFlipBit< 0 > .. EvFlipBit< NO_OF_BITS - 1 > there is a transition from
// each state to the state with the corresponding bit toggled. That is, there
// is a total of 2^NO_OF_BITS * NO_OF_BITS transitions.
// E.g. if the state machine is currently in state BitState< 5 > and receives
// EvFlipBit< 2 >, it transitions to state BitState< 1 >. If it is in
// BitState< 15 > and receives EvFlipBit< 4 > it transitions to BitState< 31 >
// etc.
// The maximum size of such a state machine depends on your compiler. The
// following table gives upper limits for noOfBits. From this, rough
// following table gives upper limits for NO_OF_BITS. From this, rough
// estimates for the maximum size of any "naively" implemented boost::fsm
// machine (i.e. no attempt is made to hide inner state implementation in a
// .cpp file) can be deduced.
//
// NOTE: Due to the fact that the amount of generated code more than
// *doubles* each time noOfBits is *incremented*, build times on most
// compilers soar when noOfBits > 6.
// *doubles* each time NO_OF_BITS is *incremented*, build times on most
// compilers soar when NO_OF_BITS > 6.
//
// Compiler | max. noOfBits b | max. states s |
// Compiler | max. NO_OF_BITS b | max. states s |
// --------------|-----------------|----------------|
// MSVC 7.1 | b < 7 | 64 < s < 128 |
// GCC 3.2 (1) | b < 8 | 128 < s < 256 |
@@ -125,8 +127,8 @@ struct IDisplay
namespace
{
const unsigned int noOfStates = 1 << noOfBits;
const unsigned int noOfTransitions = noOfStates * noOfBits;
const unsigned int noOfStates = 1 << NO_OF_BITS;
const unsigned int noOfTransitions = noOfStates * NO_OF_BITS;
// common prime factors of 2^n-1 for n in [1,8]
const unsigned int noOfEvents = 3 * 3 * 5 * 7 * 17 * 31 * 127;
@@ -137,12 +139,12 @@ namespace
////////////////////////////////////////////////////////////////////////////
void DisplayBits( unsigned int number )
{
char buffer[ noOfBits + 1 ];
buffer[ noOfBits ] = 0;
char buffer[ NO_OF_BITS + 1 ];
buffer[ NO_OF_BITS ] = 0;
for ( unsigned int bit = 0; bit < noOfBits; ++bit )
for ( unsigned int bit = 0; bit < NO_OF_BITS; ++bit )
{
buffer[ bit ] = number & ( 1 << ( noOfBits - bit - 1 ) ) ? '1' : '0';
buffer[ bit ] = number & ( 1 << ( NO_OF_BITS - bit - 1 ) ) ? '1' : '0';
}
std::cout << "Current state: " << std::setw( 4 ) <<
@@ -156,7 +158,7 @@ namespace
}
////////////////////////////////////////////////////////////////////////////
boost::intrusive_ptr< const fsm::event_base > pFlipBitEvents[ noOfBits ];
boost::intrusive_ptr< const fsm::event_base > pFlipBitEvents[ NO_OF_BITS ];
////////////////////////////////////////////////////////////////////////////
template< unsigned int arraySize >
@@ -239,7 +241,7 @@ struct FlipTransitionList
private:
//////////////////////////////////////////////////////////////////////////
typedef mpl::fold<
mpl::range_c< unsigned int, 0, noOfBits >,
mpl::range_c< unsigned int, 0, NO_OF_BITS >,
mpl::list<>, mpl::push_front< _, _ > >::type
BitNumbers;
@@ -271,13 +273,13 @@ struct BitState :
//////////////////////////////////////////////////////////////////////////////
int main()
{
FillEventArray< noOfBits >();
FillEventArray< NO_OF_BITS >();
std::cout << "boost::fsm BitMachine example\n";
std::cout << "Machine configuration: " << noOfStates <<
" states interconnected with " << noOfTransitions << " transitions.\n\n";
for ( unsigned int bit = 0; bit < noOfBits; ++bit )
for ( unsigned int bit = 0; bit < NO_OF_BITS; ++bit )
{
std::cout << bit - 0 << "<CR>: Flips bit " << bit - 0 << "\n";
}
@@ -295,7 +297,7 @@ int main()
while ( key != 'e' )
{
if ( ( key >= '0' ) && ( key < static_cast< char >( '0' + noOfBits ) ) )
if ( ( key >= '0' ) && ( key < static_cast< char >( '0' + NO_OF_BITS ) ) )
{
bitMachine.process_event( *pFlipBitEvents[ key - '0' ] );
++eventsSentTotal;
@@ -307,7 +309,7 @@ int main()
{
case 'a':
{
VisitAllStates< noOfBits - 1, true >( bitMachine );
VisitAllStates< NO_OF_BITS - 1, true >( bitMachine );
}
break;
@@ -325,7 +327,7 @@ int main()
for ( unsigned int lap = 0; lap < noOfLaps; ++lap )
{
VisitAllStates< noOfBits - 1, false >( bitMachine );
VisitAllStates< NO_OF_BITS - 1, false >( bitMachine );
}
#ifdef BOOST_NO_STDC_NAMESPACE