Cloning.h revision 2b6d2eb2d0e44eb8d897fce107961767b9676a79
1//===- Cloning.h - Clone various parts of LLVM programs ---------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines various functions that are used to clone chunks of LLVM 11// code for various purposes. This varies from copying whole modules into new 12// modules, to cloning functions with different arguments, to inlining 13// functions, to copying basic blocks to support loop unrolling or superblock 14// formation, etc. 15// 16//===----------------------------------------------------------------------===// 17 18#ifndef LLVM_TRANSFORMS_UTILS_CLONING_H 19#define LLVM_TRANSFORMS_UTILS_CLONING_H 20 21#include <vector> 22#include <map> 23 24namespace llvm { 25 26class Module; 27class Function; 28class BasicBlock; 29class Value; 30class CallInst; 31class InvokeInst; 32class ReturnInst; 33class CallSite; 34class Trace; 35 36/// CloneModule - Return an exact copy of the specified module 37/// 38Module *CloneModule(const Module *M); 39 40/// CloneBasicBlock - Return a copy of the specified basic block, but without 41/// embedding the block into a particular function. The block returned is an 42/// exact copy of the specified basic block, without any remapping having been 43/// performed. Because of this, this is only suitable for applications where 44/// the basic block will be inserted into the same function that it was cloned 45/// from (loop unrolling would use this, for example). 46/// 47/// Also, note that this function makes a direct copy of the basic block, and 48/// can thus produce illegal LLVM code. In particular, it will copy any PHI 49/// nodes from the original block, even though there are no predecessors for the 50/// newly cloned block (thus, phi nodes will have to be updated). Also, this 51/// block will branch to the old successors of the original block: these 52/// successors will have to have any PHI nodes updated to account for the new 53/// incoming edges. 54/// 55/// The correlation between instructions in the source and result basic blocks 56/// is recorded in the ValueMap map. 57/// 58/// If you have a particular suffix you'd like to use to add to any cloned 59/// names, specify it as the optional third parameter. 60/// 61/// If you would like the basic block to be auto-inserted into the end of a 62/// function, you can specify it as the optional fourth parameter. 63/// 64BasicBlock *CloneBasicBlock(const BasicBlock *BB, 65 std::map<const Value*, Value*> &ValueMap, 66 const char *NameSuffix = "", Function *F = 0); 67 68 69/// CloneFunction - Return a copy of the specified function, but without 70/// embedding the function into another module. Also, any references specified 71/// in the ValueMap are changed to refer to their mapped value instead of the 72/// original one. If any of the arguments to the function are in the ValueMap, 73/// the arguments are deleted from the resultant function. The ValueMap is 74/// updated to include mappings from all of the instructions and basicblocks in 75/// the function from their old to new values. 76/// 77Function *CloneFunction(const Function *F, 78 std::map<const Value*, Value*> &ValueMap); 79 80/// CloneFunction - Version of the function that doesn't need the ValueMap. 81/// 82inline Function *CloneFunction(const Function *F) { 83 std::map<const Value*, Value*> ValueMap; 84 return CloneFunction(F, ValueMap); 85} 86 87/// Clone OldFunc into NewFunc, transforming the old arguments into references 88/// to ArgMap values. Note that if NewFunc already has basic blocks, the ones 89/// cloned into it will be added to the end of the function. This function 90/// fills in a list of return instructions, and can optionally append the 91/// specified suffix to all values cloned. 92/// 93void CloneFunctionInto(Function *NewFunc, const Function *OldFunc, 94 std::map<const Value*, Value*> &ValueMap, 95 std::vector<ReturnInst*> &Returns, 96 const char *NameSuffix = ""); 97 98 99/// CloneTraceInto - Clone T into NewFunc. Original<->clone mapping is 100/// saved in ValueMap. 101/// 102void CloneTraceInto(Function *NewFunc, Trace &T, 103 std::map<const Value*, Value*> &ValueMap, 104 const char *NameSuffix); 105 106/// InlineFunction - This function inlines the called function into the basic 107/// block of the caller. This returns false if it is not possible to inline 108/// this call. The program is still in a well defined state if this occurs 109/// though. 110/// 111/// Note that this only does one level of inlining. For example, if the 112/// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now 113/// exists in the instruction stream. Similiarly this will inline a recursive 114/// function by one level. 115/// 116bool InlineFunction(CallInst *C); 117bool InlineFunction(InvokeInst *II); 118bool InlineFunction(CallSite CS); 119 120/// CloneTrace - Returns a copy of the specified trace. 121/// It takes a vector of basic blocks clones the basic blocks, removes internal 122/// phi nodes, adds it to the same function as the original (although there is 123/// no jump to it) and returns the new vector of basic blocks. 124std::vector<BasicBlock *> CloneTrace(const std::vector<BasicBlock*> &origTrace); 125 126} // End llvm namespace 127 128#endif 129