Extend StringRef's edit-distance algorithm to permit an upper bound on the allowed...

[oota-llvm.git] / include / llvm / ADT / STLExtras.h

diff --git a/include/llvm/ADT/STLExtras.h b/include/llvm/ADT/STLExtras.h
index ae1a1abefda45cbb9a9c4bfe668627db1420016e..0b0346be2cc5c296bf25c119db51ac2e914ff5cf 100644 (file)
--- a/include/llvm/ADT/STLExtras.h
+++ b/include/llvm/ADT/STLExtras.h
@@ -10,17 +10,18 @@
 // 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_ADT_STLEXTRAS_H
 #define LLVM_ADT_STLEXTRAS_H
 
+#include <cstddef> // for std::size_t
+#include <cstdlib> // for qsort
 #include <functional>
+#include <iterator>
 #include <utility> // for std::pair
-#include <cstring> // for std::size_t
-#include "llvm/ADT/iterator.h"
 
 namespace llvm {
 
@@ -28,6 +29,13 @@ namespace llvm {
 //     Extra additions to <functional>
 //===----------------------------------------------------------------------===//
 
+template<class Ty>
+struct less_ptr : public std::binary_function<Ty, Ty, bool> {
+  bool operator()(const Ty* left, const Ty* right) const {
+    return *left < *right;
+  }
+};
+
 template<class Ty>
 struct greater_ptr : public std::binary_function<Ty, Ty, bool> {
   bool operator()(const Ty* left, const Ty* right) const {
@@ -217,25 +225,30 @@ inline T *array_endof(T (&x)[N]) {
 
 /// Find the length of an array.
 template<class T, std::size_t N>
-inline size_t array_lengthof(T (&x)[N]) {
+inline size_t array_lengthof(T (&)[N]) {
   return N;
 }
 
 /// array_pod_sort_comparator - This is helper function for array_pod_sort,
-/// which does a memcmp of a specific size.
-template<unsigned Size>
+/// which just uses operator< on T.
+template<typename T>
 static inline int array_pod_sort_comparator(const void *P1, const void *P2) {
-  if (Size == sizeof(char))
-    return *(const char*)P1 - *(const char*)P2;
-  if (Size == sizeof(int))
-    return *(const int*)P1 - *(const int*)P2;
-  if (Size == sizeof(long long))
-    return *(const long long*)P1 - *(const long long*)P2;
-  if (Size == sizeof(intptr_t))
-    return *(intptr_t*)P1 - *(intptr_t*)P2;
-  return memcmp(P1, P2, Size);
+  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 &))
+             (const void*, const void*) {
+  return array_pod_sort_comparator<T>;
+}
+
+
 /// 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
@@ -245,8 +258,8 @@ static inline int array_pod_sort_comparator(const void *P1, const void *P2) {
 /// possible.
 ///
 /// This function assumes that you have simple POD-like types that can be
-/// compared with memcmp and can be moved with memcpy.  If this isn't true, you
-/// should use std::sort.
+/// 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.
@@ -254,10 +267,40 @@ 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),
-        array_pod_sort_comparator<sizeof(*Start)>);
+  qsort(&*Start, End-Start, sizeof(*Start),
+        get_array_pad_sort_comparator(*Start));
+}
+
+template<class IteratorTy>
+static inline void array_pod_sort(IteratorTy Start, IteratorTy End,
+                                  int (*Compare)(const void*, const void*)) {
+  // Don't dereference start iterator of empty sequence.
+  if (Start == End) return;
+  qsort(&*Start, End-Start, sizeof(*Start), Compare);
 }
   
+//===----------------------------------------------------------------------===//
+//     Extra additions to <algorithm>
+//===----------------------------------------------------------------------===//
+
+/// For a container of pointers, deletes the pointers and then clears the
+/// container.
+template<typename Container>
+void DeleteContainerPointers(Container &C) {
+  for (typename Container::iterator I = C.begin(), E = C.end(); I != E; ++I)
+    delete *I;
+  C.clear();
+}
+
+/// In a container of pairs (usually a map) whose second element is a pointer,
+/// deletes the second elements and then clears the container.
+template<typename Container>
+void DeleteContainerSeconds(Container &C) {
+  for (typename Container::iterator I = C.begin(), E = C.end(); I != E; ++I)
+    delete I->second;
+  C.clear();
+}
+
 } // End llvm namespace
 
 #endif