- //===- RandomIRBuilder.h - Utils for randomly mutation IR -------*- C++ -*-===// 
- // 
- // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
- // See https://llvm.org/LICENSE.txt for license information. 
- // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
- // 
- //===----------------------------------------------------------------------===// 
- // 
- // Provides the Mutator class, which is used to mutate IR for fuzzing. 
- // 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_FUZZMUTATE_RANDOMIRBUILDER_H 
- #define LLVM_FUZZMUTATE_RANDOMIRBUILDER_H 
-   
- #include "llvm/ADT/ArrayRef.h" 
- #include "llvm/ADT/SmallVector.h" 
- #include <random> 
-   
- namespace llvm { 
- class BasicBlock; 
- class Instruction; 
- class LLVMContext; 
- class Type; 
- class Value; 
- namespace fuzzerop { 
- class SourcePred; 
- } 
-   
- using RandomEngine = std::mt19937; 
-   
- struct RandomIRBuilder { 
-   RandomEngine Rand; 
-   SmallVector<Type *, 16> KnownTypes; 
-   
-   RandomIRBuilder(int Seed, ArrayRef<Type *> AllowedTypes) 
-       : Rand(Seed), KnownTypes(AllowedTypes.begin(), AllowedTypes.end()) {} 
-   
-   // TODO: Try to make this a bit less of a random mishmash of functions. 
-   
-   /// Find a "source" for some operation, which will be used in one of the 
-   /// operation's operands. This either selects an instruction in \c Insts or 
-   /// returns some new arbitrary Value. 
-   Value *findOrCreateSource(BasicBlock &BB, ArrayRef<Instruction *> Insts); 
-   /// Find a "source" for some operation, which will be used in one of the 
-   /// operation's operands. This either selects an instruction in \c Insts that 
-   /// matches \c Pred, or returns some new Value that matches \c Pred. The 
-   /// values in \c Srcs should be source operands that have already been 
-   /// selected. 
-   Value *findOrCreateSource(BasicBlock &BB, ArrayRef<Instruction *> Insts, 
-                             ArrayRef<Value *> Srcs, fuzzerop::SourcePred Pred, 
-                             bool allowConstant = true); 
-   /// Create some Value suitable as a source for some operation. 
-   Value *newSource(BasicBlock &BB, ArrayRef<Instruction *> Insts, 
-                    ArrayRef<Value *> Srcs, fuzzerop::SourcePred Pred, 
-                    bool allowConstant = true); 
-   /// Find a viable user for \c V in \c Insts, which should all be contained in 
-   /// \c BB. This may also create some new instruction in \c BB and use that. 
-   void connectToSink(BasicBlock &BB, ArrayRef<Instruction *> Insts, Value *V); 
-   /// Create a user for \c V in \c BB. 
-   void newSink(BasicBlock &BB, ArrayRef<Instruction *> Insts, Value *V); 
-   Value *findPointer(BasicBlock &BB, ArrayRef<Instruction *> Insts, 
-                      ArrayRef<Value *> Srcs, fuzzerop::SourcePred Pred); 
-   Type *chooseType(LLVMContext &Context, ArrayRef<Value *> Srcs, 
-                    fuzzerop::SourcePred Pred); 
-   /// Return a uniformly choosen type from \c AllowedTypes 
-   Type *randomType(); 
- }; 
-   
- } // namespace llvm 
-   
- #endif // LLVM_FUZZMUTATE_RANDOMIRBUILDER_H 
-