Add operator< for FoldingSetNodeID.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163454 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/FoldingSet.h

@@ -278,6 +278,10 @@ public:
 
   bool operator==(FoldingSetNodeIDRef) const;
 
+  /// Used to compare the "ordering" of two nodes as defined by the
+  /// profiled bits and their ordering defined by memcmp().
+  bool operator<(FoldingSetNodeIDRef) const;
+
   const unsigned *getData() const { return Data; }
   size_t getSize() const { return Size; }
 };
@@ -327,6 +331,11 @@ public:
   bool operator==(const FoldingSetNodeID &RHS) const;
   bool operator==(const FoldingSetNodeIDRef RHS) const;
 
+  /// Used to compare the "ordering" of two nodes as defined by the
+  /// profiled bits and their ordering defined by memcmp().
+  bool operator<(const FoldingSetNodeID &RHS) const;
+  bool operator<(const FoldingSetNodeIDRef RHS) const;
+
   /// Intern - Copy this node's data to a memory region allocated from the
   /// given allocator and return a FoldingSetNodeIDRef describing the
   /// interned data.

lib/Support/FoldingSet.cpp

@@ -38,6 +38,14 @@ bool FoldingSetNodeIDRef::operator==(FoldingSetNodeIDRef RHS) const {
   return memcmp(Data, RHS.Data, Size*sizeof(*Data)) == 0;
 }
 
+/// Used to compare the "ordering" of two nodes as defined by the
+/// profiled bits and their ordering defined by memcmp().
+bool FoldingSetNodeIDRef::operator<(FoldingSetNodeIDRef RHS) const {
+  if (Size != RHS.Size)
+    return Size < RHS.Size;
+  return memcmp(Data, RHS.Data, Size*sizeof(*Data)) < 0;
+}
+
 //===----------------------------------------------------------------------===//
 // FoldingSetNodeID Implementation
 
@@ -152,6 +160,16 @@ bool FoldingSetNodeID::operator==(FoldingSetNodeIDRef RHS) const {
   return FoldingSetNodeIDRef(Bits.data(), Bits.size()) == RHS;
 }
 
+/// Used to compare the "ordering" of two nodes as defined by the
+/// profiled bits and their ordering defined by memcmp().
+bool FoldingSetNodeID::operator<(const FoldingSetNodeID &RHS)const{
+  return *this < FoldingSetNodeIDRef(RHS.Bits.data(), RHS.Bits.size());
+}
+
+bool FoldingSetNodeID::operator<(FoldingSetNodeIDRef RHS) const {
+  return FoldingSetNodeIDRef(Bits.data(), Bits.size()) < RHS;
+}
+
 /// Intern - Copy this node's data to a memory region allocated from the
 /// given allocator and return a FoldingSetNodeIDRef describing the
 /// interned data.