llvm-6502/include/llvm/Module.h
Nick Lewycky 53b2b73643 Remove the last improper use of getGlobalContext() from LLVM.
This caused a race condition where a thread calls ~LLVMContextImpl which calls
Module::dropAllReferences which calls begin() on an empty ilist that would
create the sentinel, which racily accesses the global context.

This can not be fixed by locking inside createSentinel because the lock would
need to be shared with all users of the global context, including those that
reside outside LLVM's own code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137546 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-13 01:04:44 +00:00

547 lines
22 KiB
C++

//===-- llvm/Module.h - C++ class to represent a VM module ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// @file
/// Module.h This file contains the declarations for the Module class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MODULE_H
#define LLVM_MODULE_H
#include "llvm/Function.h"
#include "llvm/GlobalVariable.h"
#include "llvm/GlobalAlias.h"
#include "llvm/Metadata.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/Support/DataTypes.h"
#include <vector>
namespace llvm {
class FunctionType;
class GVMaterializer;
class LLVMContext;
class StructType;
template<typename T> struct DenseMapInfo;
template<typename KeyT, typename ValueT,
typename KeyInfoT, typename ValueInfoT> class DenseMap;
template<> struct ilist_traits<Function>
: public SymbolTableListTraits<Function, Module> {
// createSentinel is used to get hold of the node that marks the end of the
// list... (same trick used here as in ilist_traits<Instruction>)
Function *createSentinel() const {
return static_cast<Function*>(&Sentinel);
}
static void destroySentinel(Function*) {}
Function *provideInitialHead() const { return createSentinel(); }
Function *ensureHead(Function*) const { return createSentinel(); }
static void noteHead(Function*, Function*) {}
private:
mutable ilist_node<Function> Sentinel;
};
template<> struct ilist_traits<GlobalVariable>
: public SymbolTableListTraits<GlobalVariable, Module> {
// createSentinel is used to create a node that marks the end of the list.
GlobalVariable *createSentinel() const {
return static_cast<GlobalVariable*>(&Sentinel);
}
static void destroySentinel(GlobalVariable*) {}
GlobalVariable *provideInitialHead() const { return createSentinel(); }
GlobalVariable *ensureHead(GlobalVariable*) const { return createSentinel(); }
static void noteHead(GlobalVariable*, GlobalVariable*) {}
private:
mutable ilist_node<GlobalVariable> Sentinel;
};
template<> struct ilist_traits<GlobalAlias>
: public SymbolTableListTraits<GlobalAlias, Module> {
// createSentinel is used to create a node that marks the end of the list.
GlobalAlias *createSentinel() const {
return static_cast<GlobalAlias*>(&Sentinel);
}
static void destroySentinel(GlobalAlias*) {}
GlobalAlias *provideInitialHead() const { return createSentinel(); }
GlobalAlias *ensureHead(GlobalAlias*) const { return createSentinel(); }
static void noteHead(GlobalAlias*, GlobalAlias*) {}
private:
mutable ilist_node<GlobalAlias> Sentinel;
};
template<> struct ilist_traits<NamedMDNode>
: public ilist_default_traits<NamedMDNode> {
// createSentinel is used to get hold of a node that marks the end of
// the list...
NamedMDNode *createSentinel() const {
return static_cast<NamedMDNode*>(&Sentinel);
}
static void destroySentinel(NamedMDNode*) {}
NamedMDNode *provideInitialHead() const { return createSentinel(); }
NamedMDNode *ensureHead(NamedMDNode*) const { return createSentinel(); }
static void noteHead(NamedMDNode*, NamedMDNode*) {}
void addNodeToList(NamedMDNode *) {}
void removeNodeFromList(NamedMDNode *) {}
private:
mutable ilist_node<NamedMDNode> Sentinel;
};
/// A Module instance is used to store all the information related to an
/// LLVM module. Modules are the top level container of all other LLVM
/// Intermediate Representation (IR) objects. Each module directly contains a
/// list of globals variables, a list of functions, a list of libraries (or
/// other modules) this module depends on, a symbol table, and various data
/// about the target's characteristics.
///
/// A module maintains a GlobalValRefMap object that is used to hold all
/// constant references to global variables in the module. When a global
/// variable is destroyed, it should have no entries in the GlobalValueRefMap.
/// @brief The main container class for the LLVM Intermediate Representation.
class Module {
/// @name Types And Enumerations
/// @{
public:
/// The type for the list of global variables.
typedef iplist<GlobalVariable> GlobalListType;
/// The type for the list of functions.
typedef iplist<Function> FunctionListType;
/// The type for the list of aliases.
typedef iplist<GlobalAlias> AliasListType;
/// The type for the list of named metadata.
typedef ilist<NamedMDNode> NamedMDListType;
/// The type for the list of dependent libraries.
typedef std::vector<std::string> LibraryListType;
/// The Global Variable iterator.
typedef GlobalListType::iterator global_iterator;
/// The Global Variable constant iterator.
typedef GlobalListType::const_iterator const_global_iterator;
/// The Function iterators.
typedef FunctionListType::iterator iterator;
/// The Function constant iterator
typedef FunctionListType::const_iterator const_iterator;
/// The Global Alias iterators.
typedef AliasListType::iterator alias_iterator;
/// The Global Alias constant iterator
typedef AliasListType::const_iterator const_alias_iterator;
/// The named metadata iterators.
typedef NamedMDListType::iterator named_metadata_iterator;
/// The named metadata constant interators.
typedef NamedMDListType::const_iterator const_named_metadata_iterator;
/// The Library list iterator.
typedef LibraryListType::const_iterator lib_iterator;
/// An enumeration for describing the endianess of the target machine.
enum Endianness { AnyEndianness, LittleEndian, BigEndian };
/// An enumeration for describing the size of a pointer on the target machine.
enum PointerSize { AnyPointerSize, Pointer32, Pointer64 };
/// @}
/// @name Member Variables
/// @{
private:
LLVMContext &Context; ///< The LLVMContext from which types and
///< constants are allocated.
GlobalListType GlobalList; ///< The Global Variables in the module
FunctionListType FunctionList; ///< The Functions in the module
AliasListType AliasList; ///< The Aliases in the module
LibraryListType LibraryList; ///< The Libraries needed by the module
NamedMDListType NamedMDList; ///< The named metadata in the module
std::string GlobalScopeAsm; ///< Inline Asm at global scope.
ValueSymbolTable *ValSymTab; ///< Symbol table for values
OwningPtr<GVMaterializer> Materializer; ///< Used to materialize GlobalValues
std::string ModuleID; ///< Human readable identifier for the module
std::string TargetTriple; ///< Platform target triple Module compiled on
std::string DataLayout; ///< Target data description
void *NamedMDSymTab; ///< NamedMDNode names.
friend class Constant;
/// @}
/// @name Constructors
/// @{
public:
/// The Module constructor. Note that there is no default constructor. You
/// must provide a name for the module upon construction.
explicit Module(StringRef ModuleID, LLVMContext& C);
/// The module destructor. This will dropAllReferences.
~Module();
/// @}
/// @name Module Level Accessors
/// @{
/// Get the module identifier which is, essentially, the name of the module.
/// @returns the module identifier as a string
const std::string &getModuleIdentifier() const { return ModuleID; }
/// Get the data layout string for the module's target platform. This encodes
/// the type sizes and alignments expected by this module.
/// @returns the data layout as a string
const std::string &getDataLayout() const { return DataLayout; }
/// Get the target triple which is a string describing the target host.
/// @returns a string containing the target triple.
const std::string &getTargetTriple() const { return TargetTriple; }
/// Get the target endian information.
/// @returns Endianess - an enumeration for the endianess of the target
Endianness getEndianness() const;
/// Get the target pointer size.
/// @returns PointerSize - an enumeration for the size of the target's pointer
PointerSize getPointerSize() const;
/// Get the global data context.
/// @returns LLVMContext - a container for LLVM's global information
LLVMContext &getContext() const { return Context; }
/// Get any module-scope inline assembly blocks.
/// @returns a string containing the module-scope inline assembly blocks.
const std::string &getModuleInlineAsm() const { return GlobalScopeAsm; }
/// @}
/// @name Module Level Mutators
/// @{
/// Set the module identifier.
void setModuleIdentifier(StringRef ID) { ModuleID = ID; }
/// Set the data layout
void setDataLayout(StringRef DL) { DataLayout = DL; }
/// Set the target triple.
void setTargetTriple(StringRef T) { TargetTriple = T; }
/// Set the module-scope inline assembly blocks.
void setModuleInlineAsm(StringRef Asm) {
GlobalScopeAsm = Asm;
if (!GlobalScopeAsm.empty() &&
GlobalScopeAsm[GlobalScopeAsm.size()-1] != '\n')
GlobalScopeAsm += '\n';
}
/// Append to the module-scope inline assembly blocks, automatically inserting
/// a separating newline if necessary.
void appendModuleInlineAsm(StringRef Asm) {
GlobalScopeAsm += Asm;
if (!GlobalScopeAsm.empty() &&
GlobalScopeAsm[GlobalScopeAsm.size()-1] != '\n')
GlobalScopeAsm += '\n';
}
/// @}
/// @name Generic Value Accessors
/// @{
/// getNamedValue - Return the global value in the module with
/// the specified name, of arbitrary type. This method returns null
/// if a global with the specified name is not found.
GlobalValue *getNamedValue(StringRef Name) const;
/// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
/// This ID is uniqued across modules in the current LLVMContext.
unsigned getMDKindID(StringRef Name) const;
/// getMDKindNames - Populate client supplied SmallVector with the name for
/// custom metadata IDs registered in this LLVMContext.
void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
typedef DenseMap<StructType*, unsigned, DenseMapInfo<StructType*>,
DenseMapInfo<unsigned> > NumeredTypesMapTy;
/// findUsedStructTypes - Walk the entire module and find all of the
/// struct types that are in use, returning them in a vector.
void findUsedStructTypes(std::vector<StructType*> &StructTypes) const;
/// getTypeByName - Return the type with the specified name, or null if there
/// is none by that name.
StructType *getTypeByName(StringRef Name) const;
/// @}
/// @name Function Accessors
/// @{
/// getOrInsertFunction - Look up the specified function in the module symbol
/// table. Four possibilities:
/// 1. If it does not exist, add a prototype for the function and return it.
/// 2. If it exists, and has a local linkage, the existing function is
/// renamed and a new one is inserted.
/// 3. Otherwise, if the existing function has the correct prototype, return
/// the existing function.
/// 4. Finally, the function exists but has the wrong prototype: return the
/// function with a constantexpr cast to the right prototype.
Constant *getOrInsertFunction(StringRef Name, FunctionType *T,
AttrListPtr AttributeList);
Constant *getOrInsertFunction(StringRef Name, FunctionType *T);
/// getOrInsertFunction - Look up the specified function in the module symbol
/// table. If it does not exist, add a prototype for the function and return
/// it. This function guarantees to return a constant of pointer to the
/// specified function type or a ConstantExpr BitCast of that type if the
/// named function has a different type. This version of the method takes a
/// null terminated list of function arguments, which makes it easier for
/// clients to use.
Constant *getOrInsertFunction(StringRef Name,
AttrListPtr AttributeList,
Type *RetTy, ...) END_WITH_NULL;
/// getOrInsertFunction - Same as above, but without the attributes.
Constant *getOrInsertFunction(StringRef Name, Type *RetTy, ...)
END_WITH_NULL;
Constant *getOrInsertTargetIntrinsic(StringRef Name,
FunctionType *Ty,
AttrListPtr AttributeList);
/// getFunction - Look up the specified function in the module symbol table.
/// If it does not exist, return null.
Function *getFunction(StringRef Name) const;
/// @}
/// @name Global Variable Accessors
/// @{
/// getGlobalVariable - Look up the specified global variable in the module
/// symbol table. If it does not exist, return null. If AllowInternal is set
/// to true, this function will return types that have InternalLinkage. By
/// default, these types are not returned.
GlobalVariable *getGlobalVariable(StringRef Name,
bool AllowInternal = false) const;
/// getNamedGlobal - Return the global variable in the module with the
/// specified name, of arbitrary type. This method returns null if a global
/// with the specified name is not found.
GlobalVariable *getNamedGlobal(StringRef Name) const {
return getGlobalVariable(Name, true);
}
/// getOrInsertGlobal - Look up the specified global in the module symbol
/// table.
/// 1. If it does not exist, add a declaration of the global and return it.
/// 2. Else, the global exists but has the wrong type: return the function
/// with a constantexpr cast to the right type.
/// 3. Finally, if the existing global is the correct declaration, return
/// the existing global.
Constant *getOrInsertGlobal(StringRef Name, Type *Ty);
/// @}
/// @name Global Alias Accessors
/// @{
/// getNamedAlias - Return the global alias in the module with the
/// specified name, of arbitrary type. This method returns null if a global
/// with the specified name is not found.
GlobalAlias *getNamedAlias(StringRef Name) const;
/// @}
/// @name Named Metadata Accessors
/// @{
/// getNamedMetadata - Return the NamedMDNode in the module with the
/// specified name. This method returns null if a NamedMDNode with the
/// specified name is not found.
NamedMDNode *getNamedMetadata(const Twine &Name) const;
/// getOrInsertNamedMetadata - Return the named MDNode in the module
/// with the specified name. This method returns a new NamedMDNode if a
/// NamedMDNode with the specified name is not found.
NamedMDNode *getOrInsertNamedMetadata(StringRef Name);
/// eraseNamedMetadata - Remove the given NamedMDNode from this module
/// and delete it.
void eraseNamedMetadata(NamedMDNode *NMD);
/// @}
/// @name Materialization
/// @{
/// setMaterializer - Sets the GVMaterializer to GVM. This module must not
/// yet have a Materializer. To reset the materializer for a module that
/// already has one, call MaterializeAllPermanently first. Destroying this
/// module will destroy its materializer without materializing any more
/// GlobalValues. Without destroying the Module, there is no way to detach or
/// destroy a materializer without materializing all the GVs it controls, to
/// avoid leaving orphan unmaterialized GVs.
void setMaterializer(GVMaterializer *GVM);
/// getMaterializer - Retrieves the GVMaterializer, if any, for this Module.
GVMaterializer *getMaterializer() const { return Materializer.get(); }
/// isMaterializable - True if the definition of GV has yet to be materialized
/// from the GVMaterializer.
bool isMaterializable(const GlobalValue *GV) const;
/// isDematerializable - Returns true if this GV was loaded from this Module's
/// GVMaterializer and the GVMaterializer knows how to dematerialize the GV.
bool isDematerializable(const GlobalValue *GV) const;
/// Materialize - Make sure the GlobalValue is fully read. If the module is
/// corrupt, this returns true and fills in the optional string with
/// information about the problem. If successful, this returns false.
bool Materialize(GlobalValue *GV, std::string *ErrInfo = 0);
/// Dematerialize - If the GlobalValue is read in, and if the GVMaterializer
/// supports it, release the memory for the function, and set it up to be
/// materialized lazily. If !isDematerializable(), this method is a noop.
void Dematerialize(GlobalValue *GV);
/// MaterializeAll - Make sure all GlobalValues in this Module are fully read.
/// If the module is corrupt, this returns true and fills in the optional
/// string with information about the problem. If successful, this returns
/// false.
bool MaterializeAll(std::string *ErrInfo = 0);
/// MaterializeAllPermanently - Make sure all GlobalValues in this Module are
/// fully read and clear the Materializer. If the module is corrupt, this
/// returns true, fills in the optional string with information about the
/// problem, and DOES NOT clear the old Materializer. If successful, this
/// returns false.
bool MaterializeAllPermanently(std::string *ErrInfo = 0);
/// @}
/// @name Direct access to the globals list, functions list, and symbol table
/// @{
/// Get the Module's list of global variables (constant).
const GlobalListType &getGlobalList() const { return GlobalList; }
/// Get the Module's list of global variables.
GlobalListType &getGlobalList() { return GlobalList; }
static iplist<GlobalVariable> Module::*getSublistAccess(GlobalVariable*) {
return &Module::GlobalList;
}
/// Get the Module's list of functions (constant).
const FunctionListType &getFunctionList() const { return FunctionList; }
/// Get the Module's list of functions.
FunctionListType &getFunctionList() { return FunctionList; }
static iplist<Function> Module::*getSublistAccess(Function*) {
return &Module::FunctionList;
}
/// Get the Module's list of aliases (constant).
const AliasListType &getAliasList() const { return AliasList; }
/// Get the Module's list of aliases.
AliasListType &getAliasList() { return AliasList; }
static iplist<GlobalAlias> Module::*getSublistAccess(GlobalAlias*) {
return &Module::AliasList;
}
/// Get the symbol table of global variable and function identifiers
const ValueSymbolTable &getValueSymbolTable() const { return *ValSymTab; }
/// Get the Module's symbol table of global variable and function identifiers.
ValueSymbolTable &getValueSymbolTable() { return *ValSymTab; }
/// @}
/// @name Global Variable Iteration
/// @{
global_iterator global_begin() { return GlobalList.begin(); }
const_global_iterator global_begin() const { return GlobalList.begin(); }
global_iterator global_end () { return GlobalList.end(); }
const_global_iterator global_end () const { return GlobalList.end(); }
bool global_empty() const { return GlobalList.empty(); }
/// @}
/// @name Function Iteration
/// @{
iterator begin() { return FunctionList.begin(); }
const_iterator begin() const { return FunctionList.begin(); }
iterator end () { return FunctionList.end(); }
const_iterator end () const { return FunctionList.end(); }
size_t size() const { return FunctionList.size(); }
bool empty() const { return FunctionList.empty(); }
/// @}
/// @name Dependent Library Iteration
/// @{
/// @brief Get a constant iterator to beginning of dependent library list.
inline lib_iterator lib_begin() const { return LibraryList.begin(); }
/// @brief Get a constant iterator to end of dependent library list.
inline lib_iterator lib_end() const { return LibraryList.end(); }
/// @brief Returns the number of items in the list of libraries.
inline size_t lib_size() const { return LibraryList.size(); }
/// @brief Add a library to the list of dependent libraries
void addLibrary(StringRef Lib);
/// @brief Remove a library from the list of dependent libraries
void removeLibrary(StringRef Lib);
/// @brief Get all the libraries
inline const LibraryListType& getLibraries() const { return LibraryList; }
/// @}
/// @name Alias Iteration
/// @{
alias_iterator alias_begin() { return AliasList.begin(); }
const_alias_iterator alias_begin() const { return AliasList.begin(); }
alias_iterator alias_end () { return AliasList.end(); }
const_alias_iterator alias_end () const { return AliasList.end(); }
size_t alias_size () const { return AliasList.size(); }
bool alias_empty() const { return AliasList.empty(); }
/// @}
/// @name Named Metadata Iteration
/// @{
named_metadata_iterator named_metadata_begin() { return NamedMDList.begin(); }
const_named_metadata_iterator named_metadata_begin() const {
return NamedMDList.begin();
}
named_metadata_iterator named_metadata_end() { return NamedMDList.end(); }
const_named_metadata_iterator named_metadata_end() const {
return NamedMDList.end();
}
size_t named_metadata_size() const { return NamedMDList.size(); }
bool named_metadata_empty() const { return NamedMDList.empty(); }
/// @}
/// @name Utility functions for printing and dumping Module objects
/// @{
/// Print the module to an output stream with an optional
/// AssemblyAnnotationWriter.
void print(raw_ostream &OS, AssemblyAnnotationWriter *AAW) const;
/// Dump the module to stderr (for debugging).
void dump() const;
/// This function causes all the subinstructions to "let go" of all references
/// that they are maintaining. This allows one to 'delete' a whole class at
/// a time, even though there may be circular references... first all
/// references are dropped, and all use counts go to zero. Then everything
/// is delete'd for real. Note that no operations are valid on an object
/// that has "dropped all references", except operator delete.
void dropAllReferences();
/// @}
};
/// An raw_ostream inserter for modules.
inline raw_ostream &operator<<(raw_ostream &O, const Module &M) {
M.print(O, 0);
return O;
}
} // End llvm namespace
#endif