1 //===-- llvm/LLVMContext.h - Class for managing "global" state --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares LLVMContext, a container of "global" state in LLVM, such
11 // as the global type and constant uniquing tables.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_LLVMCONTEXT_H
16 #define LLVM_LLVMCONTEXT_H
18 #include "llvm/Support/DataTypes.h"
28 class ConstantAggregateZero;
32 class ConstantPointerNull;
37 class LLVMContextImpl;
50 /// This is an important class for using LLVM in a threaded context. It
51 /// (opaquely) owns and manages the core "global" data of LLVM's core
52 /// infrastructure, including the type and constant uniquing tables.
53 /// LLVMContext itself provides no locking guarantees, so you should be careful
54 /// to have one context per thread.
56 LLVMContextImpl* pImpl;
58 friend class ConstantInt;
59 friend class ConstantFP;
60 friend class ConstantStruct;
61 friend class ConstantArray;
62 friend class ConstantVector;
63 friend class ConstantAggregateZero;
69 Constant* getNullValue(const Type* Ty);
71 /// @returns the value for an integer constant of the given type that has all
72 /// its bits set to true.
73 /// @brief Get the all ones value
74 Constant* getAllOnesValue(const Type* Ty);
77 MDNode* getMDNode(Value* const* Vals, unsigned NumVals);
80 MDString* getMDString(const StringRef &Str);
83 // Methods for erasing constants
84 void erase(MDString *M);
85 void erase(MDNode *M);
88 /// FOR BACKWARDS COMPATIBILITY - Returns a global context.
89 extern LLVMContext& getGlobalContext();