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"
30 /// This class provides the interface for handling bytecode events during
31 /// reading of bytecode. The methods on this interface are invoked by the
32 /// BytecodeReader as it discovers the content of a bytecode stream.
33 /// This class provides a a clear separation of concerns between recognizing
34 /// the semantic units of a bytecode file (the Reader) and deciding what to do
35 /// with them (the Handler).
37 /// The BytecodeReader recognizes the content of the bytecode file and
38 /// calls the BytecodeHandler methods to let it perform additional tasks. This
39 /// arrangement allows Bytecode files to be read and handled for a number of
40 /// purposes simply by creating a subclass of BytecodeHandler. None of the
41 /// parsing details need to be understood, only the meaning of the calls
42 /// made on this interface.
44 /// @see BytecodeHandler
45 /// @brief Handle Bytecode Parsing Events
46 class BytecodeHandler {
48 /// @name Constructors And Operators
51 /// @brief Default constructor (empty)
53 /// @brief Virtual destructor (empty)
54 virtual ~BytecodeHandler();
57 BytecodeHandler(const BytecodeHandler &); // DO NOT IMPLEMENT
58 void operator=(const BytecodeHandler &); // DO NOT IMPLEMENT
61 /// @name Handler Methods
65 /// This method is called whenever the parser detects an error in the
66 /// bytecode formatting. It gives the handler a chance to do something
67 /// with the error message before the parser throws an exception to
68 /// terminate the parsing.
69 /// @brief Handle parsing errors.
70 virtual void handleError(const std::string& str ) {}
72 /// This method is called at the beginning of a parse before anything is
73 /// read in order to give the handler a chance to initialize.
74 /// @brief Handle the start of a bytecode parse
75 virtual void handleStart( Module* Mod, unsigned byteSize ) {}
77 /// This method is called at the end of a parse after everything has been
78 /// read in order to give the handler a chance to terminate.
79 /// @brief Handle the end of a bytecode parse
80 virtual void handleFinish() {}
82 /// This method is called at the start of a module to indicate that a
83 /// module is being parsed.
84 /// @brief Handle the start of a module.
85 virtual void handleModuleBegin(const std::string& moduleId) {}
87 /// This method is called at the end of a module to indicate that the module
88 /// previously being parsed has concluded.
89 /// @brief Handle the end of a module.
90 virtual void handleModuleEnd(
91 const std::string& moduleId ///< An identifier for the module
94 /// This method is called once the version information has been parsed. It
95 /// provides the information about the version of the bytecode file being
97 /// @brief Handle the bytecode prolog
98 virtual void handleVersionInfo(
99 unsigned char RevisionNum ///< Byte code revision number
102 /// This method is called at the start of a module globals block which
103 /// contains the global variables and the function placeholders
104 virtual void handleModuleGlobalsBegin() {}
106 /// This method is called when a non-initialized global variable is
107 /// recognized. Its type, constness, and linkage type are provided.
108 /// @brief Handle a non-initialized global variable
109 virtual void handleGlobalVariable(
110 const Type* ElemType, ///< The type of the global variable
111 bool isConstant, ///< Whether the GV is constant or not
112 GlobalValue::LinkageTypes,///< The linkage type of the GV
113 GlobalValue::VisibilityTypes,///< The visibility style of the GV
114 unsigned SlotNum, ///< Slot number of GV
115 unsigned initSlot, ///< Slot number of GV's initializer (0 if none)
116 bool isThreadLocal ///< Whether the GV is thread local or not
119 virtual void handleGlobalAlias(
120 const Type* ElemType,
121 GlobalValue::LinkageTypes Linkage,
122 unsigned TypeSlotNum,
123 unsigned AliaseeSlot) { }
125 /// This method is called when a type list is recognized. It simply
126 /// provides the number of types that the list contains. The handler
127 /// should expect that number of calls to handleType.
128 /// @brief Handle a type
129 virtual void handleTypeList(
130 unsigned numEntries ///< The number of entries in the type list
133 /// This method is called when a new type is recognized. The type is
134 /// converted from the bytecode and passed to this method.
135 /// @brief Handle a type
136 virtual void handleType(
137 const Type* Ty ///< The type that was just recognized
140 /// This method is called when the function prototype for a function is
141 /// encountered in the module globals block.
142 virtual void handleFunctionDeclaration(
143 Function* Func ///< The function being declared
146 /// This method is called when a global variable is initialized with
147 /// its constant value. Because of forward referencing, etc. this is
148 /// done towards the end of the module globals block
149 virtual void handleGlobalInitializer(GlobalVariable*, Constant* ) {}
151 /// This method is called for each dependent library name found
152 /// in the module globals block.
153 virtual void handleDependentLibrary(const std::string& libName) {}
155 /// This method is called if the module globals has a non-empty target
157 virtual void handleTargetTriple(const std::string& triple) {}
159 /// This method is called at the end of the module globals block.
160 /// @brief Handle end of module globals block.
161 virtual void handleModuleGlobalsEnd() {}
163 /// @brief Handle start of a symbol table
164 virtual void handleTypeSymbolTableBegin(
165 TypeSymbolTable* ST ///< The symbol table being filled
168 /// @brief Handle start of a symbol table
169 virtual void handleValueSymbolTableBegin(
170 Function* Func, ///< The function to which the ST belongs or 0 for Mod
171 ValueSymbolTable* ST ///< The symbol table being filled
174 /// @brief Handle a named type in the symbol table
175 virtual void handleSymbolTableType(
176 unsigned i, ///< The index of the type in this plane
177 unsigned slot, ///< Slot number of the named type
178 const std::string& name ///< Name of the type
181 /// @brief Handle a named value in the symbol table
182 virtual void handleSymbolTableValue(
183 unsigned i, ///< The index of the value in this plane
184 unsigned slot, ///< Slot number of the named value
185 const char *name, unsigned NameLen ///< Name of the value.
188 /// @brief Handle the end of a value symbol table
189 virtual void handleTypeSymbolTableEnd() {}
191 /// @brief Handle the end of a type symbol table
192 virtual void handleValueSymbolTableEnd() {}
194 /// @brief Handle the beginning of a function body
195 virtual void handleFunctionBegin(
196 Function* Func, ///< The function being defined
197 unsigned Size ///< The size (in bytes) of the function's bytecode
200 /// @brief Handle the end of a function body
201 virtual void handleFunctionEnd(
202 Function* Func ///< The function whose definition has just finished.
205 /// @brief Handle the beginning of a basic block
206 virtual void handleBasicBlockBegin(
207 unsigned blocknum ///< The block number of the block
210 /// This method is called for each instruction that is parsed.
211 /// @returns true if the instruction is a block terminating instruction
212 /// @brief Handle an instruction
213 virtual bool handleInstruction(
214 unsigned Opcode, ///< Opcode of the instruction
215 const Type* iType, ///< Instruction type
216 unsigned *Operands, unsigned NumOps, ///< Vector of slot # operands
217 Instruction *Inst, ///< The resulting instruction
218 unsigned Length ///< Length of instruction in bc bytes
221 /// @brief Handle the end of a basic block
222 virtual void handleBasicBlockEnd(
223 unsigned blocknum ///< The block number of the block just finished
226 /// @brief Handle start of global constants block.
227 virtual void handleGlobalConstantsBegin() {}
229 /// @brief Handle a constant expression
230 virtual void handleConstantExpression(
231 unsigned Opcode, ///< Opcode of primary expression operator
232 Constant**Args, unsigned NumArgs, ///< expression args
233 Constant* C ///< The constant value
236 /// @brief Handle a constant array
237 virtual void handleConstantArray(
238 const ArrayType* AT, ///< Type of the array
239 Constant**ElementSlots, unsigned NumElts,///< Slot nums for array values
240 unsigned TypeSlot, ///< Slot # of type
241 Constant* Val ///< The constant value
244 /// @brief Handle a constant structure
245 virtual void handleConstantStruct(
246 const StructType* ST, ///< Type of the struct
247 Constant**ElementSlots, unsigned NumElts,///< Slot nums for struct values
248 Constant* Val ///< The constant value
251 /// @brief Handle a constant packed
252 virtual void handleConstantVector(
253 const VectorType* PT, ///< Type of the array
254 Constant**ElementSlots, unsigned NumElts,///< Slot nums for packed values
255 unsigned TypeSlot, ///< Slot # of type
256 Constant* Val ///< The constant value
259 /// @brief Handle a constant pointer
260 virtual void handleConstantPointer(
261 const PointerType* PT, ///< Type of the pointer
262 unsigned Slot, ///< Slot num of initializer value
263 GlobalValue* GV ///< Referenced global value
266 /// @brief Handle a constant strings (array special case)
267 virtual void handleConstantString(
268 const ConstantArray* CA ///< Type of the string array
271 /// @brief Handle a primitive constant value
272 virtual void handleConstantValue(
273 Constant * c ///< The constant just defined
276 /// @brief Handle the end of the global constants
277 virtual void handleGlobalConstantsEnd() {}
279 /// @brief Handle an alignment event
280 virtual void handleAlignment(
281 unsigned numBytes ///< The number of bytes added for alignment
284 /// @brief Handle a bytecode block
285 virtual void handleBlock(
286 unsigned BType, ///< The type of block
287 const unsigned char* StartPtr, ///< The start of the block
288 unsigned Size ///< The size of the block