//===-- Reader.h - Interface To Bytecode Reading ----------------*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Reid Spencer and is distributed under the
+// This file was developed by Reid Spencer and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
-// This header file defines the interface to the Bytecode Reader which is
+// This header file defines the interface to the Bytecode Reader which is
// responsible for correctly interpreting bytecode files (backwards compatible)
// and materializing a module from the bytecode read.
//
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/GlobalValue.h"
-#include "llvm/Function.h"
#include "llvm/ModuleProvider.h"
#include "llvm/Bytecode/Analyzer.h"
+#include "llvm/ADT/SmallVector.h"
#include <utility>
-#include <map>
+#include <setjmp.h>
namespace llvm {
-class BytecodeHandler; ///< Forward declare the handler interface
+// Forward declarations
+class BytecodeHandler;
+class TypeSymbolTable;
+class ValueSymbolTable;
/// This class defines the interface for parsing a buffer of bytecode. The
/// parser itself takes no action except to call the various functions of
/// the handler interface. The parser's sole responsibility is the correct
-/// interpretation of the bytecode buffer. The handler is responsible for
-/// instantiating and keeping track of all values. As a convenience, the parser
+/// interpretation of the bytecode buffer. The handler is responsible for
+/// instantiating and keeping track of all values. As a convenience, the parser
/// is responsible for materializing types and will pass them through the
/// handler interface as necessary.
/// @see BytecodeHandler
/// @{
public:
/// @brief Default constructor. By default, no handler is used.
- BytecodeReader(
- BytecodeHandler* h = 0
- ) {
- Handler = h;
+ BytecodeReader(BytecodeHandler* h = 0) {
+ decompressedBlock = 0;
+ Handler = h;
}
- ~BytecodeReader() { freeState(); }
+ ~BytecodeReader() {
+ freeState();
+ if (decompressedBlock) {
+ ::free(decompressedBlock);
+ decompressedBlock = 0;
+ }
+ }
/// @}
/// @name Types
/// constants with global variables at the end of reading the
/// globals section.
/// @brief A list of values as a User of those Values.
- struct ValueList : public User {
- ValueList() : User(Type::VoidTy, Value::ValueListVal) {}
+ class ValueList : public User {
+ SmallVector<Use, 32> Uses;
+ public:
+ ValueList() : User(Type::VoidTy, Value::ArgumentVal, 0, 0) {}
// vector compatibility methods
unsigned size() const { return getNumOperands(); }
- void push_back(Value *V) { Operands.push_back(Use(V, this)); }
- Value *back() const { return Operands.back(); }
- void pop_back() { Operands.pop_back(); }
- bool empty() const { return Operands.empty(); }
- // must override this
+ void push_back(Value *V) {
+ Uses.push_back(Use(V, this));
+ OperandList = &Uses[0];
+ ++NumOperands;
+ }
+ Value *back() const { return Uses.back(); }
+ void pop_back() { Uses.pop_back(); --NumOperands; }
+ bool empty() const { return NumOperands == 0; }
virtual void print(std::ostream& os) const {
- for ( unsigned i = 0; i < size(); i++ ) {
+ for (unsigned i = 0; i < size(); ++i) {
os << i << " ";
getOperand(i)->print(os);
os << "\n";
/// @brief A 2 dimensional table of values
typedef std::vector<ValueList*> ValueTable;
- /// This map is needed so that forward references to constants can be looked
+ /// This map is needed so that forward references to constants can be looked
/// up by Type and slot number when resolving those references.
/// @brief A mapping of a Type/slot pair to a Constant*.
- typedef std::map<std::pair<const Type*,unsigned>, Constant*> ConstantRefsType;
+ typedef std::map<std::pair<unsigned,unsigned>, Constant*> ConstantRefsType;
/// For lazy read-in of functions, we need to save the location in the
/// data stream where the function is located. This structure provides that
/// information. Lazy read-in is used mostly by the JIT which only wants to
- /// resolve functions as it needs them.
+ /// resolve functions as it needs them.
/// @brief Keeps pointers to function contents for later use.
struct LazyFunctionInfo {
const unsigned char *Buf, *EndBuf;
/// them.
typedef std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitsList;
+ /// @brief A list of global aliases and the slot number for constant aliasees
+ typedef std::vector<std::pair<GlobalAlias*, unsigned> > AliaseeList;
+
/// This type maps a typeslot/valueslot pair to the corresponding Value*.
/// It is used for dealing with forward references as values are read in.
/// @brief A map for dealing with forward references of values.
/// @name Methods
/// @{
public:
+ typedef size_t BCDecompressor_t(const char *, size_t, char*&, std::string*);
+
+ /// @returns true if an error occurred
/// @brief Main interface to parsing a bytecode buffer.
- void ParseBytecode(
- const unsigned char *Buf, ///< Beginning of the bytecode buffer
+ bool ParseBytecode(
+ volatile BufPtr Buf, ///< Beginning of the bytecode buffer
unsigned Length, ///< Length of the bytecode buffer
- const std::string &ModuleID ///< An identifier for the module constructed.
+ const std::string &ModuleID, ///< An identifier for the module constructed.
+ BCDecompressor_t *Decompressor = 0, ///< Optional decompressor.
+ std::string* ErrMsg = 0 ///< Optional place for error message
);
/// @brief Parse all function bodies
- void ParseAllFunctionBodies();
+ bool ParseAllFunctionBodies(std::string* ErrMsg);
/// @brief Parse the next function of specific type
- void ParseFunction(Function* Func) ;
+ bool ParseFunction(Function* Func, std::string* ErrMsg);
/// This method is abstract in the parent ModuleProvider class. Its
/// implementation is identical to the ParseFunction method.
/// @see ParseFunction
/// @brief Make a specific function materialize.
- virtual void materializeFunction(Function *F) {
- LazyFunctionMap::iterator Fi = LazyFunctionLoadMap.find(F);
- if (Fi == LazyFunctionLoadMap.end()) return;
- ParseFunction(F);
+ virtual bool materializeFunction(Function *F, std::string *ErrMsg = 0) {
+ // If it already is material, ignore the request.
+ if (!F->hasNotBeenReadFromBytecode()) return false;
+
+ assert(LazyFunctionLoadMap.count(F) &&
+ "not materialized but I don't know about it?");
+ if (ParseFunction(F,ErrMsg))
+ return true;
+ return false;
+ }
+
+ /// dematerializeFunction - If the given function is read in, and if the
+ /// module provider supports it, release the memory for the function, and set
+ /// it up to be materialized lazily. If the provider doesn't support this
+ /// capability, this method is a noop.
+ ///
+ virtual void dematerializeFunction(Function *F) {
+ // If the function is not materialized, or if it is a prototype, ignore.
+ if (F->hasNotBeenReadFromBytecode() ||
+ F->isDeclaration())
+ return;
+
+ // Just forget the function body, we can remat it later.
+ F->deleteBody();
+ F->setLinkage(GlobalValue::GhostLinkage);
}
/// This method is abstract in the parent ModuleProvider class. Its
- /// implementation is identical to ParseAllFunctionBodies.
+ /// implementation is identical to ParseAllFunctionBodies.
/// @see ParseAllFunctionBodies
/// @brief Make the whole module materialize
- virtual Module* materializeModule() {
- ParseAllFunctionBodies();
+ virtual Module* materializeModule(std::string *ErrMsg = 0) {
+ if (ParseAllFunctionBodies(ErrMsg))
+ return 0;
return TheModule;
}
/// here. It simply releases the module from its provided and frees up our
/// state.
/// @brief Release our hold on the generated module
- Module* releaseModule() {
+ Module* releaseModule(std::string *ErrInfo = 0) {
// Since we're losing control of this Module, we must hand it back complete
- Module *M = ModuleProvider::releaseModule();
+ Module *M = ModuleProvider::releaseModule(ErrInfo);
freeState();
return M;
}
/// @brief Parse the ModuleGlobalInfo block
void ParseModuleGlobalInfo();
- /// @brief Parse a symbol table
- void ParseSymbolTable( Function* Func, SymbolTable *ST);
+ /// @brief Parse a value symbol table
+ void ParseTypeSymbolTable(TypeSymbolTable *ST);
+
+ /// @brief Parse a value symbol table
+ void ParseValueSymbolTable(Function* Func, ValueSymbolTable *ST);
/// @brief Parse functions lazily.
void ParseFunctionLazily();
/// @brief Parse a function body
void ParseFunctionBody(Function* Func);
- /// @brief Parse the type list portion of a compaction table
- void ParseCompactionTypes(unsigned NumEntries);
-
- /// @brief Parse a compaction table
- void ParseCompactionTable();
-
/// @brief Parse global types
void ParseGlobalTypes();
+
/// @brief Parse a basic block (for LLVM 1.0 basic block blocks)
BasicBlock* ParseBasicBlock(unsigned BlockNo);
unsigned ParseInstructionList(
Function* F ///< The function into which BBs will be inserted
);
-
+
/// @brief Parse a single instruction.
void ParseInstruction(
- std::vector<unsigned>& Args, ///< The arguments to be filled in
+ SmallVector <unsigned, 8>& Args, ///< The arguments to be filled in
BasicBlock* BB ///< The BB the instruction goes in
);
/// @brief Parse the whole constant pool
- void ParseConstantPool(ValueTable& Values, TypeListTy& Types,
+ void ParseConstantPool(ValueTable& Values, TypeListTy& Types,
bool isFunction);
- /// @brief Parse a single constant value
- Constant* ParseConstantValue(unsigned TypeID);
+ /// @brief Parse a single constant pool value
+ Value *ParseConstantPoolValue(unsigned TypeID);
/// @brief Parse a block of types constants
void ParseTypes(TypeListTy &Tab, unsigned NumEntries);
/// @brief Parse a single type constant
const Type *ParseType();
+ /// @brief Parse a list of parameter attributes
+ ParamAttrsList *ParseParamAttrsList();
+
/// @brief Parse a string constants block
void ParseStringConstants(unsigned NumEntries, ValueTable &Tab);
+ /// @brief Release our memory.
+ void freeState() {
+ freeTable(FunctionValues);
+ freeTable(ModuleValues);
+ }
+
/// @}
/// @name Data
/// @{
private:
+ std::string ErrorMsg; ///< A place to hold an error message through longjmp
+ jmp_buf context; ///< Where to return to if an error occurs.
+ char* decompressedBlock; ///< Result of decompression
BufPtr MemStart; ///< Start of the memory buffer
BufPtr MemEnd; ///< End of the memory buffer
BufPtr BlockStart; ///< Start of current block being parsed
///
unsigned char RevisionNum; // The rev # itself
- /// Flags to distinguish LLVM 1.0 & 1.1 bytecode formats (revision #0)
-
- /// Revision #0 had an explicit alignment of data only for the
- /// ModuleGlobalInfo block. This was fixed to be like all other blocks in 1.2
- bool hasInconsistentModuleGlobalInfo;
-
- /// Revision #0 also explicitly encoded zero values for primitive types like
- /// int/sbyte/etc.
- bool hasExplicitPrimitiveZeros;
-
- // Flags to control features specific the LLVM 1.2 and before (revision #1)
-
- /// LLVM 1.2 and earlier required that getelementptr structure indices were
- /// ubyte constants and that sequential type indices were longs.
- bool hasRestrictedGEPTypes;
-
- /// LLVM 1.2 and earlier had class Type deriving from Value and the Type
- /// objects were located in the "Type Type" plane of various lists in read
- /// by the bytecode reader. In LLVM 1.3 this is no longer the case. Types are
- /// completely distinct from Values. Consequently, Types are written in fixed
- /// locations in LLVM 1.3. This flag indicates that the older Type derived
- /// from Value style of bytecode file is being read.
- bool hasTypeDerivedFromValue;
-
- /// LLVM 1.2 and earlier encoded block headers as two uint (8 bytes), one for
- /// the size and one for the type. This is a bit wasteful, especially for
- /// small files where the 8 bytes per block is a large fraction of the total
- /// block size. In LLVM 1.3, the block type and length are encoded into a
- /// single uint32 by restricting the number of block types (limit 31) and the
- /// maximum size of a block (limit 2^27-1=134,217,727). Note that the module
- /// block still uses the 8-byte format so the maximum size of a file can be
- /// 2^32-1 bytes long.
- bool hasLongBlockHeaders;
-
- /// LLVM 1.2 and earlier wrote type slot numbers as vbr_uint32. In LLVM 1.3
- /// this has been reduced to vbr_uint24. It shouldn't make much difference
- /// since we haven't run into a module with > 24 million types, but for safety
- /// the 24-bit restriction has been enforced in 1.3 to free some bits in
- /// various places and to ensure consistency. In particular, global vars are
- /// restricted to 24-bits.
- bool has32BitTypes;
-
- /// LLVM 1.2 and earlier did not provide a target triple nor a list of
- /// libraries on which the bytecode is dependent. LLVM 1.3 provides these
- /// features, for use in future versions of LLVM.
- bool hasNoDependentLibraries;
-
- /// LLVM 1.3 and earlier caused blocks and other fields to start on 32-bit
- /// aligned boundaries. This can lead to as much as 30% bytecode size overhead
- /// in various corner cases (lots of long instructions). In LLVM 1.4,
- /// alignment of bytecode fields was done away with completely.
- bool hasAlignment;
-
- // In version 4 and earlier, the bytecode format did not support the 'undef'
- // constant.
- bool hasNoUndefValue;
-
- // In version 4 and earlier, the bytecode format did not save space for flags
- // in the global info block for functions.
- bool hasNoFlagsForFunctions;
-
- // In version 4 and earlier, there was no opcode space reserved for the
- // unreachable instruction.
- bool hasNoUnreachableInst;
-
- // In version 5, basic blocks have a minimum index of 0 whereas all the
- // other primitives have a minimum index of 1 (because 0 is the "null"
- // value. In version 5, we made this consistent.
- bool hasInconsistentBBSlotNums;
-
- // In version 5, the types SByte and UByte were encoded as vbr_uint so that
- // signed values > 63 and unsigned values >127 would be encoded as two
- // bytes. In version 5, they are encoded directly in a single byte.
- bool hasVBRByteTypes;
-
- // In version 5, modules begin with a "Module Block" which encodes a 4-byte
- // integer value 0x01 to identify the module block. This is unnecessary and
- // removed in version 5.
- bool hasUnnecessaryModuleBlockId;
-
- /// CompactionTypes - If a compaction table is active in the current function,
- /// this is the mapping that it contains. We keep track of what resolved type
- /// it is as well as what global type entry it is.
- std::vector<std::pair<const Type*, unsigned> > CompactionTypes;
-
- /// @brief If a compaction table is active in the current function,
- /// this is the mapping that it contains.
- std::vector<std::vector<Value*> > CompactionValues;
-
/// @brief This vector is used to deal with forward references to types in
/// a module.
TypeListTy ModuleTypes;
+
+ /// @brief This is an inverse mapping of ModuleTypes from the type to an
+ /// index. Because refining types causes the index of this map to be
+ /// invalidated, any time we refine a type, we clear this cache and recompute
+ /// it next time we need it. These entries are ordered by the pointer value.
+ std::vector<std::pair<const Type*, unsigned> > ModuleTypeIDCache;
/// @brief This vector is used to deal with forward references to types in
/// a function.
/// of what we must do.
GlobalInitsList GlobalInits;
+ /// Constant values are read in after global aliases. Because of this, we must
+ /// defer setting the constant aliasees until after module level constants
+ /// have been read. In the mean time, this list keeps track of what we must
+ /// do.
+ AliaseeList Aliasees;
+
// For lazy reading-in of functions, we need to save away several pieces of
// information about each function: its begin and end pointer in the buffer
// and its FunctionSlot.
LazyFunctionMap LazyFunctionLoadMap;
- /// This stores the parser's handler which is used for handling tasks other
- /// just than reading bytecode into the IR. If this is non-null, calls on
- /// the (polymorphic) BytecodeHandler interface (see llvm/Bytecode/Handler.h)
- /// will be made to report the logical structure of the bytecode file. What
- /// the handler does with the events it receives is completely orthogonal to
+ /// This stores the parser's handler which is used for handling tasks other
+ /// just than reading bytecode into the IR. If this is non-null, calls on
+ /// the (polymorphic) BytecodeHandler interface (see llvm/Bytecode/Handler.h)
+ /// will be made to report the logical structure of the bytecode file. What
+ /// the handler does with the events it receives is completely orthogonal to
/// the business of parsing the bytecode and building the IR. This is used,
/// for example, by the llvm-abcd tool for analysis of byte code.
/// @brief Handler for parsing events.
BytecodeHandler* Handler;
+
/// @}
/// @name Implementation Details
/// @{
/// @brief Converts a type slot number to its Type*
const Type *getType(unsigned ID);
- /// @brief Converts a pre-sanitized type slot number to its Type* and
- /// sanitizes the type id.
- inline const Type* getSanitizedType(unsigned& ID );
-
- /// @brief Read in and get a sanitized type id
- inline const Type* BytecodeReader::readSanitizedType();
+ /// @brief Read in a type id and turn it into a Type*
+ inline const Type* readType();
/// @brief Converts a Type* to its type slot number
unsigned getTypeSlot(const Type *Ty);
- /// @brief Converts a normal type slot number to a compacted type slot num.
- unsigned getCompactionTypeSlot(unsigned type);
-
/// @brief Gets the global type corresponding to the TypeId
const Type *getGlobalTableType(unsigned TypeId);
- /// This is just like getTypeSlot, but when a compaction table is in use,
- /// it is ignored.
- unsigned getGlobalTableTypeSlot(const Type *Ty);
-
/// @brief Get a value from its typeid and slot number
Value* getValue(unsigned TypeID, unsigned num, bool Create = true);
- /// @brief Get a value from its type and slot number, ignoring compaction
- /// tables.
- Value *getGlobalTableValue(unsigned TyID, unsigned SlotNo);
-
/// @brief Get a basic block for current function
BasicBlock *getBasicBlock(unsigned ID);
/// @brief Insert the arguments of a function.
void insertArguments(Function* F );
- /// @brief Resolve all references to the placeholder (if any) for the
+ /// @brief Resolve all references to the placeholder (if any) for the
/// given constant.
- void ResolveReferencesToConstant(Constant *C, unsigned Slot);
-
- /// @brief Release our memory.
- void freeState() {
- freeTable(FunctionValues);
- freeTable(ModuleValues);
- }
+ void ResolveReferencesToConstant(Constant *C, unsigned Typ, unsigned Slot);
/// @brief Free a table, making sure to free the ValueList in the table.
void freeTable(ValueTable &Tab) {
}
}
- inline void error(std::string errmsg);
+ inline void error(const std::string& errmsg);
BytecodeReader(const BytecodeReader &); // DO NOT IMPLEMENT
void operator=(const BytecodeReader &); // DO NOT IMPLEMENT
+ // This enum provides the values of the well-known type slots that are always
+ // emitted as the first few types in the table by the BytecodeWriter class.
+ enum WellKnownTypeSlots {
+ VoidTypeSlot = 0, ///< TypeID == VoidTyID
+ FloatTySlot = 1, ///< TypeID == FloatTyID
+ DoubleTySlot = 2, ///< TypeID == DoubleTyID
+ LabelTySlot = 3, ///< TypeID == LabelTyID
+ BoolTySlot = 4, ///< TypeID == IntegerTyID, width = 1
+ Int8TySlot = 5, ///< TypeID == IntegerTyID, width = 8
+ Int16TySlot = 6, ///< TypeID == IntegerTyID, width = 16
+ Int32TySlot = 7, ///< TypeID == IntegerTyID, width = 32
+ Int64TySlot = 8 ///< TypeID == IntegerTyID, width = 64
+ };
+
/// @}
/// @name Reader Primitives
/// @{
/// @brief Read a string
inline std::string read_str();
+ inline void read_str(SmallVectorImpl<char> &StrData);
/// @brief Read a float value
inline void read_float(float& FloatVal);
/// @brief Read a bytecode block header
inline void read_block(unsigned &Type, unsigned &Size);
-
- /// @brief Read a type identifier and sanitize it.
- inline bool read_typeid(unsigned &TypeId);
-
- /// @brief Recalculate type ID for pre 1.3 bytecode files.
- inline bool sanitizeTypeId(unsigned &TypeId );
/// @}
};
-/// @brief A function for creating a BytecodeAnalzer as a handler
-/// for the Bytecode reader.
-BytecodeHandler* createBytecodeAnalyzerHandler(BytecodeAnalysis& bca,
- std::ostream* output );
-
-
} // End llvm namespace
// vim: sw=2