1 //===- Cloning.h - Clone various parts of LLVM programs ---------*- 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 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
16 //===----------------------------------------------------------------------===//
18 #ifndef LLVM_TRANSFORMS_UTILS_CLONING_H
19 #define LLVM_TRANSFORMS_UTILS_CLONING_H
21 #include "llvm/ADT/ValueMap.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/ADT/Twine.h"
24 #include "llvm/Support/ValueHandle.h"
46 /// CloneModule - Return an exact copy of the specified module
48 Module *CloneModule(const Module *M);
49 Module *CloneModule(const Module *M, ValueMap<const Value*, Value*> &VMap);
51 /// ClonedCodeInfo - This struct can be used to capture information about code
52 /// being cloned, while it is being cloned.
53 struct ClonedCodeInfo {
54 /// ContainsCalls - This is set to true if the cloned code contains a normal
58 /// ContainsUnwinds - This is set to true if the cloned code contains an
59 /// unwind instruction.
62 /// ContainsDynamicAllocas - This is set to true if the cloned code contains
63 /// a 'dynamic' alloca. Dynamic allocas are allocas that are either not in
64 /// the entry block or they are in the entry block but are not a constant
66 bool ContainsDynamicAllocas;
69 ContainsCalls = false;
70 ContainsUnwinds = false;
71 ContainsDynamicAllocas = false;
76 /// CloneBasicBlock - Return a copy of the specified basic block, but without
77 /// embedding the block into a particular function. The block returned is an
78 /// exact copy of the specified basic block, without any remapping having been
79 /// performed. Because of this, this is only suitable for applications where
80 /// the basic block will be inserted into the same function that it was cloned
81 /// from (loop unrolling would use this, for example).
83 /// Also, note that this function makes a direct copy of the basic block, and
84 /// can thus produce illegal LLVM code. In particular, it will copy any PHI
85 /// nodes from the original block, even though there are no predecessors for the
86 /// newly cloned block (thus, phi nodes will have to be updated). Also, this
87 /// block will branch to the old successors of the original block: these
88 /// successors will have to have any PHI nodes updated to account for the new
91 /// The correlation between instructions in the source and result basic blocks
92 /// is recorded in the VMap map.
94 /// If you have a particular suffix you'd like to use to add to any cloned
95 /// names, specify it as the optional third parameter.
97 /// If you would like the basic block to be auto-inserted into the end of a
98 /// function, you can specify it as the optional fourth parameter.
100 /// If you would like to collect additional information about the cloned
101 /// function, you can specify a ClonedCodeInfo object with the optional fifth
104 BasicBlock *CloneBasicBlock(const BasicBlock *BB,
105 ValueMap<const Value*, Value*> &VMap,
106 const Twine &NameSuffix = "", Function *F = 0,
107 ClonedCodeInfo *CodeInfo = 0);
110 /// CloneLoop - Clone Loop. Clone dominator info for loop insiders. Populate
111 /// VMap using old blocks to new blocks mapping.
112 Loop *CloneLoop(Loop *L, LPPassManager *LPM, LoopInfo *LI,
113 ValueMap<const Value *, Value *> &VMap, Pass *P);
115 /// CloneFunction - Return a copy of the specified function, but without
116 /// embedding the function into another module. Also, any references specified
117 /// in the VMap are changed to refer to their mapped value instead of the
118 /// original one. If any of the arguments to the function are in the VMap,
119 /// the arguments are deleted from the resultant function. The VMap is
120 /// updated to include mappings from all of the instructions and basicblocks in
121 /// the function from their old to new values. The final argument captures
122 /// information about the cloned code if non-null.
124 Function *CloneFunction(const Function *F,
125 ValueMap<const Value*, Value*> &VMap,
126 ClonedCodeInfo *CodeInfo = 0);
128 /// CloneFunction - Version of the function that doesn't need the VMap.
130 inline Function *CloneFunction(const Function *F, ClonedCodeInfo *CodeInfo = 0){
131 ValueMap<const Value*, Value*> VMap;
132 return CloneFunction(F, VMap, CodeInfo);
135 /// Clone OldFunc into NewFunc, transforming the old arguments into references
136 /// to ArgMap values. Note that if NewFunc already has basic blocks, the ones
137 /// cloned into it will be added to the end of the function. This function
138 /// fills in a list of return instructions, and can optionally append the
139 /// specified suffix to all values cloned.
141 void CloneFunctionInto(Function *NewFunc, const Function *OldFunc,
142 ValueMap<const Value*, Value*> &VMap,
143 SmallVectorImpl<ReturnInst*> &Returns,
144 const char *NameSuffix = "",
145 ClonedCodeInfo *CodeInfo = 0);
147 /// CloneAndPruneFunctionInto - This works exactly like CloneFunctionInto,
148 /// except that it does some simple constant prop and DCE on the fly. The
149 /// effect of this is to copy significantly less code in cases where (for
150 /// example) a function call with constant arguments is inlined, and those
151 /// constant arguments cause a significant amount of code in the callee to be
152 /// dead. Since this doesn't produce an exactly copy of the input, it can't be
153 /// used for things like CloneFunction or CloneModule.
154 void CloneAndPruneFunctionInto(Function *NewFunc, const Function *OldFunc,
155 ValueMap<const Value*, Value*> &VMap,
156 SmallVectorImpl<ReturnInst*> &Returns,
157 const char *NameSuffix = "",
158 ClonedCodeInfo *CodeInfo = 0,
159 const TargetData *TD = 0,
160 Instruction *TheCall = 0);
163 /// InlineFunctionInfo - This class captures the data input to the
164 /// InlineFunction call, and records the auxiliary results produced by it.
165 class InlineFunctionInfo {
167 explicit InlineFunctionInfo(CallGraph *cg = 0, const TargetData *td = 0)
170 /// CG - If non-null, InlineFunction will update the callgraph to reflect the
171 /// changes it makes.
173 const TargetData *TD;
175 /// StaticAllocas - InlineFunction fills this in with all static allocas that
176 /// get copied into the caller.
177 SmallVector<AllocaInst*, 4> StaticAllocas;
179 /// InlinedCalls - InlineFunction fills this in with callsites that were
180 /// inlined from the callee. This is only filled in if CG is non-null.
181 SmallVector<WeakVH, 8> InlinedCalls;
184 StaticAllocas.clear();
185 InlinedCalls.clear();
189 /// InlineFunction - This function inlines the called function into the basic
190 /// block of the caller. This returns false if it is not possible to inline
191 /// this call. The program is still in a well defined state if this occurs
194 /// Note that this only does one level of inlining. For example, if the
195 /// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now
196 /// exists in the instruction stream. Similiarly this will inline a recursive
197 /// function by one level.
199 bool InlineFunction(CallInst *C, InlineFunctionInfo &IFI);
200 bool InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI);
201 bool InlineFunction(CallSite CS, InlineFunctionInfo &IFI);
203 } // End llvm namespace