Add a helper useful when mapping from a map element to its hash node.

llvm-svn: 42480
This commit is contained in:
Chris Lattner 2007-09-30 08:31:46 +00:00
parent 6c44b9f145
commit b06396c588
1 changed files with 12 additions and 1 deletions

View File

@ -166,7 +166,18 @@ public:
MallocAllocator A;
return Create(KeyStart, KeyEnd, A);
}
/// GetStringMapEntryFromValue - Given a value that is known to be embedded
/// into a StringMapEntry, return the StringMapEntry itself.
static StringMapEntry &GetStringMapEntryFromValue(ValueTy &V) {
return *reinterpret_cast<StringMapEntry*>(reinterpret_cast<char*>(&V) -
sizeof(StringMapEntryBase));
}
static const StringMapEntry &GetStringMapEntryFromValue(const ValueTy &V) {
return GetStringMapEntryFromValue(const_cast<ValueTy&>(V));
}
/// Destroy - Destroy this StringMapEntry, releasing memory back to the
/// specified allocator.
template<typename AllocatorTy>