1 //===-- BytecodeHandler.h - Handle Bytecode Parsing Events ------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Reid Spencer and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header file defines the interface to the Bytecode Handler. The handler
11 // is called by the Bytecode Reader to obtain out-of-band parsing events for
12 // tasks other then LLVM IR construction.
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_BYTECODE_BYTECODEHANDLER_H
17 #define LLVM_BYTECODE_BYTECODEHANDLER_H
19 #include "llvm/Module.h"
29 /// This class provides the interface for handling bytecode events during
30 /// reading of bytecode. The methods on this interface are invoked by the
31 /// BytecodeReader as it discovers the content of a bytecode stream.
32 /// This class provides a a clear separation of concerns between recognizing
33 /// the semantic units of a bytecode file (the Reader) and deciding what to do
34 /// with them (the Handler).
36 /// The BytecodeReader recognizes the content of the bytecode file and
37 /// calls the BytecodeHandler methods to let it perform additional tasks. This
38 /// arrangement allows Bytecode files to be read and handled for a number of
39 /// purposes simply by creating a subclass of BytecodeHandler. None of the
40 /// parsing details need to be understood, only the meaning of the calls
41 /// made on this interface.
43 /// @see BytecodeHandler
44 /// @brief Handle Bytecode Parsing Events
45 class BytecodeHandler {
47 /// @name Constructors And Operators
50 /// @brief Default constructor (empty)
52 /// @brief Virtual destructor (empty)
53 virtual ~BytecodeHandler();
56 BytecodeHandler(const BytecodeHandler &); // DO NOT IMPLEMENT
57 void operator=(const BytecodeHandler &); // DO NOT IMPLEMENT
60 /// @name Handler Methods
64 /// This method is called whenever the parser detects an error in the
65 /// bytecode formatting. It gives the handler a chance to do something
66 /// with the error message before the parser throws an exception to
67 /// terminate the parsing.
68 /// @brief Handle parsing errors.
69 virtual void handleError(const std::string& str ) {}
71 /// This method is called at the beginning of a parse before anything is
72 /// read in order to give the handler a chance to initialize.
73 /// @brief Handle the start of a bytecode parse
74 virtual void handleStart( Module* Mod, unsigned byteSize ) {}
76 /// This method is called at the end of a parse after everything has been
77 /// read in order to give the handler a chance to terminate.
78 /// @brief Handle the end of a bytecode parse
79 virtual void handleFinish() {}
81 /// This method is called at the start of a module to indicate that a
82 /// module is being parsed.
83 /// @brief Handle the start of a module.
84 virtual void handleModuleBegin(const std::string& moduleId) {}
86 /// This method is called at the end of a module to indicate that the module
87 /// previously being parsed has concluded.
88 /// @brief Handle the end of a module.
89 virtual void handleModuleEnd(
90 const std::string& moduleId ///< An identifier for the module
93 /// This method is called once the version information has been parsed. It
94 /// provides the information about the version of the bytecode file being
96 /// @brief Handle the bytecode prolog
97 virtual void handleVersionInfo(
98 unsigned char RevisionNum, ///< Byte code revision number
99 Module::Endianness Endianness, ///< Endianness indicator
100 Module::PointerSize PointerSize ///< PointerSize indicator
103 /// This method is called at the start of a module globals block which
104 /// contains the global variables and the function placeholders
105 virtual void handleModuleGlobalsBegin() {}
107 /// This method is called when a non-initialized global variable is
108 /// recognized. Its type, constness, and linkage type are provided.
109 /// @brief Handle a non-initialized global variable
110 virtual void handleGlobalVariable(
111 const Type* ElemType, ///< The type of the global variable
112 bool isConstant, ///< Whether the GV is constant or not
113 GlobalValue::LinkageTypes,///< The linkage type of the GV
114 unsigned SlotNum, ///< Slot number of GV
115 unsigned initSlot ///< Slot number of GV's initializer (0 if none)
118 /// This method is called when a new type is recognized. The type is
119 /// converted from the bytecode and passed to this method.
120 /// @brief Handle a type
121 virtual void handleType(
122 const Type* Ty ///< The type that was just recognized
125 /// This method is called when the function prototype for a function is
126 /// encountered in the module globals block.
127 virtual void handleFunctionDeclaration(
128 Function* Func ///< The function being declared
131 /// This method is called when a global variable is initialized with
132 /// its constant value. Because of forward referencing, etc. this is
133 /// done towards the end of the module globals block
134 virtual void handleGlobalInitializer(GlobalVariable*, Constant* ) {}
136 /// This method is called at the end of the module globals block.
137 /// @brief Handle end of module globals block.
138 virtual void handleModuleGlobalsEnd() {}
140 /// This method is called at the beginning of a compaction table.
141 /// @brief Handle start of compaction table.
142 virtual void handleCompactionTableBegin() {}
144 /// @brief Handle start of a compaction table plane
145 virtual void handleCompactionTablePlane(
146 unsigned Ty, ///< The type of the plane (slot number)
147 unsigned NumEntries ///< The number of entries in the plane
150 /// @brief Handle a type entry in the compaction table
151 virtual void handleCompactionTableType(
152 unsigned i, ///< Index in the plane of this type
153 unsigned TypSlot, ///< Slot number for this type
154 const Type* ///< The type referenced by this slot
157 /// @brief Handle a value entry in the compaction table
158 virtual void handleCompactionTableValue(
159 unsigned i, ///< Index in the compaction table's type plane
160 unsigned TypSlot, ///< The slot (plane) of the type of this value
161 unsigned ValSlot, ///< The global value slot of the value
162 const Type* ///< The resolved type of the value.
165 /// @brief Handle end of a compaction table
166 virtual void handleCompactionTableEnd() {}
168 /// @brief Handle start of a symbol table
169 virtual void handleSymbolTableBegin(
170 Function* Func, ///< The function to which the ST belongs
171 SymbolTable* ST ///< The symbol table being filled
174 /// @brief Handle start of a symbol table plane
175 virtual void handleSymbolTablePlane(
176 unsigned TySlot, ///< The slotnum of the type plane
177 unsigned NumEntries, ///< Number of entries in the plane
178 const Type* Typ ///< The type of this type plane
181 /// @brief Handle a named type in the symbol table
182 virtual void handleSymbolTableType(
183 unsigned i, ///< The index of the type in this plane
184 unsigned slot, ///< Slot number of the named type
185 const std::string& name ///< Name of the type
188 /// @brief Handle a named value in the symbol table
189 virtual void handleSymbolTableValue(
190 unsigned i, ///< The index of the value in this plane
191 unsigned slot, ///< Slot number of the named value
192 const std::string& name ///< Name of the value.
195 /// @brief Handle the end of a symbol table
196 virtual void handleSymbolTableEnd() {}
198 /// @brief Handle the beginning of a function body
199 virtual void handleFunctionBegin(
200 Function* Func, ///< The function being defined
201 unsigned Size ///< The size (in bytes) of the function's bytecode
204 /// @brief Handle the end of a function body
205 virtual void handleFunctionEnd(
206 Function* Func ///< The function whose definition has just finished.
209 /// @brief Handle the beginning of a basic block
210 virtual void handleBasicBlockBegin(
211 unsigned blocknum ///< The block number of the block
214 /// This method is called for each instruction that is parsed.
215 /// @returns true if the instruction is a block terminating instruction
216 /// @brief Handle an instruction
217 virtual bool handleInstruction(
218 unsigned Opcode, ///< Opcode of the instruction
219 const Type* iType, ///< Instruction type
220 std::vector<unsigned>& Operands, ///< Vector of slot # operands
221 unsigned Length ///< Length of instruction in bc bytes
224 /// @brief Handle the end of a basic block
225 virtual void handleBasicBlockEnd(
226 unsigned blocknum ///< The block number of the block just finished
229 /// @brief Handle start of global constants block.
230 virtual void handleGlobalConstantsBegin() {}
232 /// @brief Handle a constant expression
233 virtual void handleConstantExpression(
234 unsigned Opcode, ///< Opcode of primary expression operator
235 std::vector<Constant*> ArgVec, ///< expression args
236 Constant* C ///< The constant value
239 /// @brief Handle a constant array
240 virtual void handleConstantArray(
241 const ArrayType* AT, ///< Type of the array
242 std::vector<Constant*>& ElementSlots,///< Slot nums for array values
243 unsigned TypeSlot, ///< Slot # of type
244 Constant* Val ///< The constant value
247 /// @brief Handle a constant structure
248 virtual void handleConstantStruct(
249 const StructType* ST, ///< Type of the struct
250 std::vector<Constant*>& ElementSlots,///< Slot nums for struct values
251 Constant* Val ///< The constant value
254 /// @brief Handle a constant pointer
255 virtual void handleConstantPointer(
256 const PointerType* PT, ///< Type of the pointer
257 unsigned Slot, ///< Slot num of initializer value
258 GlobalValue* GV ///< Referenced global value
261 /// @brief Handle a constant strings (array special case)
262 virtual void handleConstantString(
263 const ConstantArray* CA ///< Type of the string array
266 /// @brief Handle a primitive constant value
267 virtual void handleConstantValue(
268 Constant * c ///< The constant just defined
271 /// @brief Handle the end of the global constants
272 virtual void handleGlobalConstantsEnd() {}
274 /// @brief Handle an alignment event
275 virtual void handleAlignment(
276 unsigned numBytes ///< The number of bytes added for alignment
279 /// @brief Handle a bytecode block
280 virtual void handleBlock(
281 unsigned BType, ///< The type of block
282 const unsigned char* StartPtr, ///< The start of the block
283 unsigned Size ///< The size of the block
286 /// @brief Handle a variable bit rate 32 bit unsigned
287 virtual void handleVBR32(
288 unsigned Size ///< Number of bytes the vbr_uint took up
291 /// @brief Handle a variable bit rate 64 bit unsigned
292 virtual void handleVBR64(
293 unsigned Size ///< Number of byte sthe vbr_uint64 took up