-//===-- STLExtras.h - Useful functions when working with the STL -*- C++ -*--=//
+//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file contains some templates that are useful if you are working with the
// STL at all.
//
-// No library is required when using these functinons.
+// No library is required when using these functions.
//
//===----------------------------------------------------------------------===//
-#ifndef LLVM_SUPPORT_STL_EXTRAS_H
-#define LLVM_SUPPORT_STL_EXTRAS_H
+#ifndef LLVM_ADT_STLEXTRAS_H
+#define LLVM_ADT_STLEXTRAS_H
+#include <cstddef> // for std::size_t
#include <functional>
+#include <utility> // for std::pair
+#include "llvm/ADT/iterator.h"
+
+namespace llvm {
//===----------------------------------------------------------------------===//
// Extra additions to <functional>
//===----------------------------------------------------------------------===//
-// bind_obj - Often times you want to apply the member function of an object
-// as a unary functor. This macro is shorthand that makes it happen less
-// verbosely.
-//
-// Example:
-// struct Summer { void accumulate(int x); }
-// vector<int> Numbers;
-// Summer MyS;
-// for_each(Numbers.begin(), Numbers.end(),
-// bind_obj(&MyS, &Summer::accumulate));
-//
-// TODO: When I get lots of extra time, convert this from an evil macro
-//
-#define bind_obj(OBJ, METHOD) std::bind1st(std::mem_fun(METHOD), OBJ)
-
-
-// bitwise_or - This is a simple functor that applys operator| on its two
-// arguments to get a boolean result.
-//
template<class Ty>
-struct bitwise_or : public std::binary_function<Ty, Ty, bool> {
- bool operator()(const Ty& left, const Ty& right) const {
- return left | right;
+struct greater_ptr : public std::binary_function<Ty, Ty, bool> {
+ bool operator()(const Ty* left, const Ty* right) const {
+ return *right < *left;
}
};
-
// deleter - Very very very simple method that is used to invoke operator
-// delete on something. It is used like this:
+// delete on something. It is used like this:
//
// for_each(V.begin(), B.end(), deleter<Interval>);
//
-template <class T>
-static inline void deleter(T *Ptr) {
- delete Ptr;
+template <class T>
+static inline void deleter(T *Ptr) {
+ delete Ptr;
}
// mapped_iterator - This is a simple iterator adapter that causes a function to
// be dereferenced whenever operator* is invoked on the iterator.
//
-// It turns out that this is disturbingly similar to boost::transform_iterator
-//
-#if 1
template <class RootIt, class UnaryFunc>
class mapped_iterator {
RootIt current;
typedef typename std::iterator_traits<RootIt>::difference_type
difference_type;
typedef typename UnaryFunc::result_type value_type;
- typedef typename UnaryFunc::result_type *pointer;
+
+ typedef void pointer;
+ //typedef typename UnaryFunc::result_type *pointer;
typedef void reference; // Can't modify value returned by fn
typedef RootIt iterator_type;
typedef mapped_iterator<RootIt, UnaryFunc> _Self;
- inline RootIt &getCurrent() const { return current; }
+ inline const RootIt &getCurrent() const { return current; }
+ inline const UnaryFunc &getFunc() const { return Fn; }
inline explicit mapped_iterator(const RootIt &I, UnaryFunc F)
: current(I), Fn(F) {}
inline mapped_iterator(const mapped_iterator &It)
: current(It.current), Fn(It.Fn) {}
- inline value_type operator*() const { // All this work to do this
+ inline value_type operator*() const { // All this work to do this
return Fn(*current); // little change
}
_Self& operator--() { --current; return *this; }
_Self operator++(int) { _Self __tmp = *this; ++current; return __tmp; }
_Self operator--(int) { _Self __tmp = *this; --current; return __tmp; }
- _Self operator+ (difference_type n) const { return _Self(current + n); }
+ _Self operator+ (difference_type n) const {
+ return _Self(current + n, Fn);
+ }
_Self& operator+= (difference_type n) { current += n; return *this; }
- _Self operator- (difference_type n) const { return _Self(current - n); }
+ _Self operator- (difference_type n) const {
+ return _Self(current - n, Fn);
+ }
_Self& operator-= (difference_type n) { current -= n; return *this; }
- reference operator[](difference_type n) const { return *(*this + n); }
+ reference operator[](difference_type n) const { return *(*this + n); }
inline bool operator!=(const _Self &X) const { return !operator==(X); }
inline bool operator==(const _Self &X) const { return current == X.current; }
};
template <class _Iterator, class Func>
-inline mapped_iterator<_Iterator, Func>
+inline mapped_iterator<_Iterator, Func>
operator+(typename mapped_iterator<_Iterator, Func>::difference_type N,
const mapped_iterator<_Iterator, Func>& X) {
- return mapped_iterator<_Iterator, Func>(X.getCurrent() - N);
+ return mapped_iterator<_Iterator, Func>(X.getCurrent() - N, X.getFunc());
}
-#else
-
-// This fails to work, because some iterators are not classes, for example
-// vector iterators are commonly value_type **'s
-template <class RootIt, class UnaryFunc>
-class mapped_iterator : public RootIt {
- UnaryFunc Fn;
-public:
- typedef typename UnaryFunc::result_type value_type;
- typedef typename UnaryFunc::result_type *pointer;
- typedef void reference; // Can't modify value returned by fn
-
- typedef mapped_iterator<RootIt, UnaryFunc> _Self;
- typedef RootIt super;
- inline explicit mapped_iterator(const RootIt &I) : super(I) {}
- inline mapped_iterator(const super &It) : super(It) {}
-
- inline value_type operator*() const { // All this work to do
- return Fn(super::operator*()); // this little thing
- }
-};
-#endif
// map_iterator - Provide a convenient way to create mapped_iterators, just like
// make_pair is useful for creating pairs...
}
-//===----------------------------------------------------------------------===//
-// Extra additions to <algorithm>
-//===----------------------------------------------------------------------===//
-
-// apply_until - Apply a functor to a sequence continually, unless the
-// functor returns true. Return true if the functor returned true, return false
-// if the functor never returned true.
+// next/prior - These functions unlike std::advance do not modify the
+// passed iterator but return a copy.
//
-template <class InputIt, class Function>
-bool apply_until(InputIt First, InputIt Last, Function Func) {
- for ( ; First != Last; ++First)
- if (Func(*First)) return true;
- return false;
+// next(myIt) returns copy of myIt incremented once
+// next(myIt, n) returns copy of myIt incremented n times
+// prior(myIt) returns copy of myIt decremented once
+// prior(myIt, n) returns copy of myIt decremented n times
+
+template <typename ItTy, typename Dist>
+inline ItTy next(ItTy it, Dist n)
+{
+ std::advance(it, n);
+ return it;
}
+template <typename ItTy>
+inline ItTy next(ItTy it)
+{
+ return ++it;
+}
-// reduce - Reduce a sequence values into a single value, given an initial
-// value and an operator.
-//
-template <class InputIt, class Function, class ValueType>
-ValueType reduce(InputIt First, InputIt Last, Function Func, ValueType Value) {
- for ( ; First != Last; ++First)
- Value = Func(*First, Value);
- return Value;
+template <typename ItTy, typename Dist>
+inline ItTy prior(ItTy it, Dist n)
+{
+ std::advance(it, -n);
+ return it;
}
-#if 1 // This is likely to be more efficient
+template <typename ItTy>
+inline ItTy prior(ItTy it)
+{
+ return --it;
+}
+
+//===----------------------------------------------------------------------===//
+// Extra additions to <utility>
+//===----------------------------------------------------------------------===//
-// reduce_apply - Reduce the result of applying a function to each value in a
-// sequence, given an initial value, an operator, a function, and a sequence.
+// tie - this function ties two objects and returns a temporary object
+// that is assignable from a std::pair. This can be used to make code
+// more readable when using values returned from functions bundled in
+// a std::pair. Since an example is worth 1000 words:
+//
+// typedef std::map<int, int> Int2IntMap;
+//
+// Int2IntMap myMap;
+// Int2IntMap::iterator where;
+// bool inserted;
+// tie(where, inserted) = myMap.insert(std::make_pair(123,456));
//
-template <class InputIt, class Function, class ValueType, class TransFunc>
-inline ValueType reduce_apply(InputIt First, InputIt Last, Function Func,
- ValueType Value, TransFunc XForm) {
- for ( ; First != Last; ++First)
- Value = Func(XForm(*First), Value);
- return Value;
+// if (inserted)
+// // do stuff
+// else
+// // do other stuff
+
+namespace
+{
+ template <typename T1, typename T2>
+ struct tier {
+ typedef T1 &first_type;
+ typedef T2 &second_type;
+
+ first_type first;
+ second_type second;
+
+ tier(first_type f, second_type s) : first(f), second(s) { }
+ tier& operator=(const std::pair<T1, T2>& p) {
+ first = p.first;
+ second = p.second;
+ return *this;
+ }
+ };
}
-#else // This is arguably more elegant
+template <typename T1, typename T2>
+inline tier<T1, T2> tie(T1& f, T2& s) {
+ return tier<T1, T2>(f, s);
+}
-// reduce_apply - Reduce the result of applying a function to each value in a
-// sequence, given an initial value, an operator, a function, and a sequence.
-//
-template <class InputIt, class Function, class ValueType, class TransFunc>
-inline ValueType reduce_apply2(InputIt First, InputIt Last, Function Func,
- ValueType Value, TransFunc XForm) {
- return reduce(map_iterator(First, XForm), map_iterator(Last, XForm),
- Func, Value);
+//===----------------------------------------------------------------------===//
+// Extra additions for arrays
+//===----------------------------------------------------------------------===//
+
+/// Find where an array ends (for ending iterators)
+/// This returns a pointer to the byte immediately
+/// after the end of an array.
+template<class T, std::size_t N>
+inline T *array_endof(T (&x)[N]) {
+ return x+N;
}
-#endif
+/// Find the length of an array.
+template<class T, std::size_t N>
+inline size_t array_lengthof(T (&x)[N]) {
+ return N;
+}
-// reduce_apply_bool - Reduce the result of applying a (bool returning) function
-// to each value in a sequence. All of the bools returned by the mapped
-// function are bitwise or'd together, and the result is returned.
-//
-template <class InputIt, class Function>
-inline bool reduce_apply_bool(InputIt First, InputIt Last, Function Func) {
- return reduce_apply(First, Last, bitwise_or<bool>(), false, Func);
+/// array_pod_sort_comparator - This is helper function for array_pod_sort,
+/// which just uses operator< on T.
+template<typename T>
+static inline int array_pod_sort_comparator(const void *P1, const void *P2) {
+ if (*reinterpret_cast<const T*>(P1) < *reinterpret_cast<const T*>(P2))
+ return -1;
+ if (*reinterpret_cast<const T*>(P2) < *reinterpret_cast<const T*>(P1))
+ return 1;
+ return 0;
}
+/// get_array_pad_sort_comparator - This is an internal helper function used to
+/// get type deduction of T right.
+template<typename T>
+static int (*get_array_pad_sort_comparator(const T &X))
+ (const void*, const void*) {
+ return array_pod_sort_comparator<T>;
+}
-// map - This function maps the specified input sequence into the specified
-// output iterator, applying a unary function in between.
-//
-template <class InIt, class OutIt, class Functor>
-inline OutIt mapto(InIt Begin, InIt End, OutIt Dest, Functor F) {
- return copy(map_iterator(Begin, F), map_iterator(End, F), Dest);
+
+/// array_pod_sort - This sorts an array with the specified start and end
+/// extent. This is just like std::sort, except that it calls qsort instead of
+/// using an inlined template. qsort is slightly slower than std::sort, but
+/// most sorts are not performance critical in LLVM and std::sort has to be
+/// template instantiated for each type, leading to significant measured code
+/// bloat. This function should generally be used instead of std::sort where
+/// possible.
+///
+/// This function assumes that you have simple POD-like types that can be
+/// compared with operator< and can be moved with memcpy. If this isn't true,
+/// you should use std::sort.
+///
+/// NOTE: If qsort_r were portable, we could allow a custom comparator and
+/// default to std::less.
+template<class IteratorTy>
+static inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
+ // Don't dereference start iterator of empty sequence.
+ if (Start == End) return;
+ qsort(&*Start, End-Start, sizeof(*Start),
+ get_array_pad_sort_comparator(*Start));
}
+
+} // End llvm namespace
+
#endif