source: src/Common/utility.h @ a5294af

//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// utility.h -- General utilities used across the compiler.
//
// Author           : Richard C. Bilson
// Created On       : Mon May 18 07:44:20 2015
// Last Modified By : Andrew Beach
// Last Modified On : Fri Feb 17 15:25:00 2023
// Update Count     : 53
//

#pragma once

#include <cassert>
#include <cctype>
#include <algorithm>
#include <iostream>
#include <list>
#include <memory>
#include <string>
#include <type_traits>
#include <vector>
#include <cstring>                                                                              // memcmp

#include "Common/Indenter.h"

class Expression;

/// bring std::move into global scope
using std::move;

/// partner to move that copies any copyable type
template<typename T>
T copy( const T & x ) { return x; }

template< typename T >
static inline T * maybeClone( const T *orig ) {
        if ( orig ) {
                return orig->clone();
        } else {
                return 0;
        } // if
}

template< typename Input_iterator >
void printEnums( Input_iterator begin, Input_iterator end, const char * const *name_array, std::ostream &os ) {
        for ( Input_iterator i = begin; i != end; ++i ) {
                os << name_array[ *i ] << ' ';
        } // for
}

template< typename Container >
void deleteAll( const Container &container ) {
        for ( const auto &i : container ) {
                delete i;
        } // for
}

template< typename Container >
void printAll( const Container &container, std::ostream &os, Indenter indent = {} ) {
        for ( typename Container::const_iterator i = container.begin(); i != container.end(); ++i ) {
                if ( *i ) {
                        os << indent;
                        (*i)->print( os, indent );
                        // need an endl after each element because it's not easy to know when each individual item should end
                        os << std::endl;
                } // if
        } // for
}

template< typename SrcContainer, typename DestContainer >
void cloneAll( const SrcContainer &src, DestContainer &dest ) {
        typename SrcContainer::const_iterator in = src.begin();
        std::back_insert_iterator< DestContainer > out( dest );
        while ( in != src.end() ) {
                *out++ = (*in++)->clone();
        } // while
}

template< typename SrcContainer, typename DestContainer, typename Predicate >
void cloneAll_if( const SrcContainer &src, DestContainer &dest, Predicate pred ) {
        std::back_insert_iterator< DestContainer > out( dest );
        for ( auto x : src ) {
                if ( pred(x) ) {
                        *out++ = x->clone();
                }
        } // while
}

template< typename Container >
void assertAll( const Container &container ) {
        int count = 0;
        for ( typename Container::const_iterator i = container.begin(); i != container.end(); ++i ) {
                if ( !(*i) ) {
                        std::cerr << count << " is null" << std::endl;
                } // if
        } // for
}

template < typename T >
std::list<T> tail( std::list<T> l ) {
        if ( ! l.empty() ) {
                std::list<T> ret(++(l.begin()), l.end());
                return ret;
        } // if
}

template < typename T >
std::list<T> flatten( std::list < std::list<T> > l) {
        typedef std::list <T> Ts;

        Ts ret;

        switch ( l.size() ) {
          case 0:
                return ret;
          case 1:
                return l.front();
          default:
                ret = flatten(tail(l));
                ret.insert(ret.begin(), l.front().begin(), l.front().end());
                return ret;
        } // switch
}

/// Splice src onto the end of dst, clearing src
template< typename T >
void splice( std::vector< T > & dst, std::vector< T > & src ) {
        dst.reserve( dst.size() + src.size() );
        for ( T & x : src ) { dst.emplace_back( std::move( x ) ); }
        src.clear();
}

/// Splice src onto the begining of dst, clearing src
template< typename T >
void spliceBegin( std::vector< T > & dst, std::vector< T > & src ) {
        splice( src, dst );
        dst.swap( src );
}

template< typename... Args >
auto filter(Args&&... args) -> decltype(std::copy_if(std::forward<Args>(args)...)) {
  return std::copy_if(std::forward<Args>(args)...);
}

template <typename E, typename UnaryPredicate, template< typename, typename...> class Container, typename... Args >
void filter( Container< E *, Args... > & container, UnaryPredicate pred, bool doDelete ) {
        auto i = begin( container );
        while ( i != end( container ) ) {
                auto it = next( i );
                if ( pred( *i ) ) {
                        if ( doDelete ) {
                                delete *i;
                        } // if
                        container.erase( i );
                } // if
                i = it;
        } // while
}

template<typename Container, typename Pred>
void erase_if( Container & cont, Pred && pred ) {
        auto keep_end = std::remove_if( cont.begin(), cont.end(), pred );
        cont.erase( keep_end, cont.end() );
}

// determines if pref is a prefix of str
static inline bool isPrefix( const std::string & str, const std::string & pref, unsigned int start = 0 ) {
        if ( pref.size() > str.size() ) return false;
        return pref == str.substr(start, pref.size());
}

// -----------------------------------------------------------------------------
// RAII object to regulate "save and restore" behaviour, e.g.
// void Foo::bar() {
//   ValueGuard<int> guard(var); // var is a member of type Foo
//   var = ...;
// } // var's original value is restored
template< typename T >
struct ValueGuard {
        T old;
        T& ref;

        ValueGuard(T& inRef) : old(inRef), ref(inRef) {}
        ~ValueGuard() { ref = old; }
};

template< typename T >
struct ValueGuardPtr {
        T old;
        T* ref;

        ValueGuardPtr(T * inRef) : old( inRef ? *inRef : T() ), ref(inRef) {}
        ValueGuardPtr(const ValueGuardPtr& other) = delete;
        ValueGuardPtr(ValueGuardPtr&& other) : old(other.old), ref(other.ref) { other.ref = nullptr; }
        ~ValueGuardPtr() { if( ref ) *ref = old; }
};

template< typename aT >
struct FuncGuard {
        aT m_after;

        template< typename bT >
        FuncGuard( bT before, aT after ) : m_after( after ) {
                before();
        }

        ~FuncGuard() {
                m_after();
        }
};

template< typename bT, typename aT >
FuncGuard<aT> makeFuncGuard( bT && before, aT && after ) {
        return FuncGuard<aT>( std::forward<bT>(before), std::forward<aT>(after) );
}

template< typename T >
struct ValueGuardPtr< std::list< T > > {
        std::list< T > old;
        std::list< T >* ref;

        ValueGuardPtr( std::list< T > * inRef) : old(), ref(inRef) {
                if( ref ) { swap( *ref, old ); }
        }
        ~ValueGuardPtr() { if( ref ) { swap( *ref, old ); } }
};

// -----------------------------------------------------------------------------
// O(1) polymorphic integer ilog2, using clz, which returns the number of leading 0-bits, starting at the most
// significant bit (single instruction on x86)

template<typename T>
inline
#if defined(__GNUC__) && __GNUC__ > 4
constexpr
#endif
T ilog2(const T & t) {
        if(std::is_integral<T>::value) {
                const constexpr int r = sizeof(t) * __CHAR_BIT__ - 1;
                if( sizeof(T) == sizeof(unsigned       int) ) return r - __builtin_clz  ( t );
                if( sizeof(T) == sizeof(unsigned      long) ) return r - __builtin_clzl ( t );
                if( sizeof(T) == sizeof(unsigned long long) ) return r - __builtin_clzll( t );
        }
        assert(false);
        return -1;
} // ilog2

// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //