1 //===- ValueMapper.h - Remapping for constants and metadata -----*- 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 the MapValue interface which is used by various parts of
11 // the Transforms/Utils library to implement cloning and linking facilities.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_TRANSFORMS_UTILS_VALUEMAPPER_H
16 #define LLVM_TRANSFORMS_UTILS_VALUEMAPPER_H
18 #include "llvm/IR/ValueMap.h"
23 typedef ValueMap<const Value *, WeakVH> ValueToValueMapTy;
25 /// ValueMapTypeRemapper - This is a class that can be implemented by clients
26 /// to remap types when cloning constants and instructions.
27 class ValueMapTypeRemapper {
28 virtual void anchor(); // Out of line method.
30 virtual ~ValueMapTypeRemapper() {}
32 /// remapType - The client should implement this method if they want to
33 /// remap types while mapping values.
34 virtual Type *remapType(Type *SrcTy) = 0;
37 /// ValueMaterializer - This is a class that can be implemented by clients
38 /// to materialize Values on demand.
39 class ValueMaterializer {
40 virtual void anchor(); // Out of line method.
43 ~ValueMaterializer() = default;
44 ValueMaterializer() = default;
45 ValueMaterializer(const ValueMaterializer&) = default;
46 ValueMaterializer &operator=(const ValueMaterializer&) = default;
49 /// The client should implement this method if they want to generate a
50 /// mapped Value on demand. For example, if linking lazily.
51 virtual Value *materializeDeclFor(Value *V) = 0;
53 /// If the data being mapped is recursive, the above function can map
54 /// just the declaration and this is called to compute the initializer.
55 /// It is called after the mapping is recorded, so it doesn't need to worry
57 virtual void materializeInitFor(GlobalValue *New, GlobalValue *Old);
59 /// If the client needs to handle temporary metadata it must implement
61 virtual Metadata *mapTemporaryMetadata(Metadata *MD) { return nullptr; }
62 virtual void replaceTemporaryMetadata(const Metadata *OrigMD,
66 /// RemapFlags - These are flags that the value mapping APIs allow.
70 /// RF_NoModuleLevelChanges - If this flag is set, the remapper knows that
71 /// only local values within a function (such as an instruction or argument)
72 /// are mapped, not global values like functions and global metadata.
73 RF_NoModuleLevelChanges = 1,
75 /// RF_IgnoreMissingEntries - If this flag is set, the remapper ignores
76 /// entries that are not in the value map. If it is unset, it aborts if an
77 /// operand is asked to be remapped which doesn't exist in the mapping.
78 RF_IgnoreMissingEntries = 2,
80 /// Instruct the remapper to move distinct metadata instead of duplicating
81 /// it when there are module-level changes.
82 RF_MoveDistinctMDs = 4,
84 /// Any global values not in value map are mapped to null instead of
85 /// mapping to self. Illegal if RF_IgnoreMissingEntries is also set.
86 RF_NullMapMissingGlobalValues = 8,
88 /// Set when there is still temporary metadata that must be handled,
89 /// such as when we are doing function importing and will materialize
90 /// and link metadata as a postpass.
91 RF_HaveUnmaterializedMetadata = 16,
94 static inline RemapFlags operator|(RemapFlags LHS, RemapFlags RHS) {
95 return RemapFlags(unsigned(LHS)|unsigned(RHS));
98 Value *MapValue(const Value *V, ValueToValueMapTy &VM,
99 RemapFlags Flags = RF_None,
100 ValueMapTypeRemapper *TypeMapper = nullptr,
101 ValueMaterializer *Materializer = nullptr);
103 Metadata *MapMetadata(const Metadata *MD, ValueToValueMapTy &VM,
104 RemapFlags Flags = RF_None,
105 ValueMapTypeRemapper *TypeMapper = nullptr,
106 ValueMaterializer *Materializer = nullptr);
108 /// MapMetadata - provide versions that preserve type safety for MDNodes.
109 MDNode *MapMetadata(const MDNode *MD, ValueToValueMapTy &VM,
110 RemapFlags Flags = RF_None,
111 ValueMapTypeRemapper *TypeMapper = nullptr,
112 ValueMaterializer *Materializer = nullptr);
114 void RemapInstruction(Instruction *I, ValueToValueMapTy &VM,
115 RemapFlags Flags = RF_None,
116 ValueMapTypeRemapper *TypeMapper = nullptr,
117 ValueMaterializer *Materializer = nullptr);
119 /// MapValue - provide versions that preserve type safety for Constants.
120 inline Constant *MapValue(const Constant *V, ValueToValueMapTy &VM,
121 RemapFlags Flags = RF_None,
122 ValueMapTypeRemapper *TypeMapper = nullptr,
123 ValueMaterializer *Materializer = nullptr) {
124 return cast<Constant>(MapValue((const Value*)V, VM, Flags, TypeMapper,
128 } // End llvm namespace