Here are the data structures with brief descriptions:

ANTLR3_ARBORETUM_struct	ANTLR3 Tree factory interface to create lots of trees efficiently rather than creating and freeing lots of little bits of memory
ANTLR3_BASE_RECOGNIZER_struct	Base tracking context structure for all types of recognizers
ANTLR3_BASE_TREE_ADAPTOR_struct
ANTLR3_BASE_TREE_struct	A generic tree implementation with no payload
ANTLR3_BITSET_LIST_struct
ANTLR3_BITSET_struct
ANTLR3_COMMON_TOKEN_STREAM_struct	Common token stream is an implementation of ANTLR_TOKEN_STREAM for the default parsers and recognizers
ANTLR3_COMMON_TOKEN_struct	The definition of an ANTLR3 common token structure, which all implementations of a token stream should provide, installing any further structures in the custom pointer element of this structure
ANTLR3_COMMON_TREE_ADAPTOR_struct
ANTLR3_COMMON_TREE_NODE_STREAM_struct
ANTLR3_COMMON_TREE_struct	Interface for an ANTLR3 common tree which is what gets passed around by the AST producing parser
ANTLR3_CYCLIC_DFA_struct	Definition of a cyclic dfa structure such that it can be initialized at compile time and have only a single runtime function that can deal with all cyclic dfa structures and show Java how it is done ;-)
ANTLR3_DEBUG_EVENT_LISTENER_struct	The ANTLR3 debugging interface for communicating with ANLTR Works
ANTLR3_EXCEPTION_struct	Base structure for an ANTLR3 exception tracker
ANTLR3_HASH_BUCKET_struct	Internal structure of a hash table bucket, which tracks all keys that hash to the same bucket
ANTLR3_HASH_ENTRY_struct	Internal structure representing an element in a hash bucket
ANTLR3_HASH_ENUM_struct	Internal structure representing an enumeration of a table
ANTLR3_HASH_KEY_struct
ANTLR3_HASH_TABLE_struct	Structure that tracks a hash table
ANTLR3_INPUT_STREAM_struct	Master context structure for an ANTLR3 C runtime based input stream
ANTLR3_INT_STREAM_struct
ANTLR3_INT_TRIE_NODE_struct	Structure that defines an element/node in an ANTLR3_INT_TRIE
ANTLR3_INT_TRIE_struct	Structure that defines an ANTLR3_INT_TRIE
ANTLR3_LEX_STATE_struct	Structure for track lex input states as part of mark() and rewind() of lexer
ANTLR3_LEXER_struct
ANTLR3_LIST_struct	Structure that represents a LIST collection
ANTLR3_PARSE_TREE_struct
ANTLR3_PARSER_struct	This is the main interface for an ANTLR3 parser
ANTLR3_RECOGNIZER_SHARED_STATE_struct	All the data elements required to track the current state of any recognizer (lexer, parser, tree parser)
ANTLR3_REWRITE_RULE_ELEMENT_STREAM_struct	A generic list of elements tracked in an alternative to be used in a -> rewrite rule
ANTLR3_STACK_struct	Structure that represents a Stack collection
ANTLR3_STRING_FACTORY_struct	Definition of the string factory interface, which creates and tracks strings for you of various shapes and sizes
ANTLR3_STRING_struct	Base string class tracks the allocations and provides simple string tracking functions
ANTLR3_TOKEN_FACTORY_struct	ANTLR3 Token factory interface to create lots of tokens efficiently rather than creating and freeing lots of little bits of memory
ANTLR3_TOKEN_SOURCE_struct	Definition of a token source, which has a pointer to a function that returns the next token (using a token factory if it is going to be efficient) and a pointer to an ANTLR3_INPUT_STREAM
ANTLR3_TOKEN_STREAM_struct	Definition of the ANTLR3 common token stream interface
ANTLR3_TOPO_struct	A topological sort system that given a set of dependencies of a node m on node n, can sort them in dependency order
ANTLR3_TREE_NODE_STREAM_struct
ANTLR3_TREE_PARSER_struct	Internal structure representing an element in a hash bucket
ANTLR3_TREE_WALK_STATE_struct	This structure is used to save the state information in the treenodestream when walking ahead with cyclic DFA or for syntactic predicates, we need to record the state of the tree node stream
ANTLR3_TRIE_ENTRY_struct	Structure that holds the payload entry in an ANTLR3_INT_TRIE or ANTLR3_STRING_TRIE
ANTLR3_VECTOR_ELEMENT_struct
ANTLR3_VECTOR_FACTORY_struct	Structure that tracks vectors in a vector and auto deletes the vectors in the vector factory when closed
ANTLR3_VECTOR_struct