LLVM  7.0.0svn
TypeFinder.cpp
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1 //===- TypeFinder.cpp - Implement the TypeFinder class --------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the TypeFinder class for the IR library.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/IR/TypeFinder.h"
15 #include "llvm/ADT/SmallVector.h"
16 #include "llvm/IR/BasicBlock.h"
17 #include "llvm/IR/Constant.h"
18 #include "llvm/IR/DerivedTypes.h"
19 #include "llvm/IR/Function.h"
20 #include "llvm/IR/Instruction.h"
21 #include "llvm/IR/Metadata.h"
22 #include "llvm/IR/Module.h"
23 #include "llvm/IR/Type.h"
24 #include "llvm/IR/Use.h"
25 #include "llvm/IR/User.h"
26 #include "llvm/IR/Value.h"
27 #include "llvm/Support/Casting.h"
28 #include <utility>
29 
30 using namespace llvm;
31 
32 void TypeFinder::run(const Module &M, bool onlyNamed) {
33  OnlyNamed = onlyNamed;
34 
35  // Get types from global variables.
36  for (const auto &G : M.globals()) {
37  incorporateType(G.getType());
38  if (G.hasInitializer())
39  incorporateValue(G.getInitializer());
40  }
41 
42  // Get types from aliases.
43  for (const auto &A : M.aliases()) {
44  incorporateType(A.getType());
45  if (const Value *Aliasee = A.getAliasee())
46  incorporateValue(Aliasee);
47  }
48 
49  // Get types from functions.
51  for (const Function &FI : M) {
52  incorporateType(FI.getType());
53 
54  for (const Use &U : FI.operands())
55  incorporateValue(U.get());
56 
57  // First incorporate the arguments.
58  for (const auto &A : FI.args())
59  incorporateValue(&A);
60 
61  for (const BasicBlock &BB : FI)
62  for (const Instruction &I : BB) {
63  // Incorporate the type of the instruction.
64  incorporateType(I.getType());
65 
66  // Incorporate non-instruction operand types. (We are incorporating all
67  // instructions with this loop.)
68  for (const auto &O : I.operands())
69  if (&*O && !isa<Instruction>(&*O))
70  incorporateValue(&*O);
71 
72  // Incorporate types hiding in metadata.
73  I.getAllMetadataOtherThanDebugLoc(MDForInst);
74  for (const auto &MD : MDForInst)
75  incorporateMDNode(MD.second);
76  MDForInst.clear();
77  }
78  }
79 
80  for (const auto &NMD : M.named_metadata())
81  for (const auto &MDOp : NMD.operands())
82  incorporateMDNode(MDOp);
83 }
84 
86  VisitedConstants.clear();
87  VisitedTypes.clear();
88  StructTypes.clear();
89 }
90 
91 /// incorporateType - This method adds the type to the list of used structures
92 /// if it's not in there already.
93 void TypeFinder::incorporateType(Type *Ty) {
94  // Check to see if we've already visited this type.
95  if (!VisitedTypes.insert(Ty).second)
96  return;
97 
98  SmallVector<Type *, 4> TypeWorklist;
99  TypeWorklist.push_back(Ty);
100  do {
101  Ty = TypeWorklist.pop_back_val();
102 
103  // If this is a structure or opaque type, add a name for the type.
104  if (StructType *STy = dyn_cast<StructType>(Ty))
105  if (!OnlyNamed || STy->hasName())
106  StructTypes.push_back(STy);
107 
108  // Add all unvisited subtypes to worklist for processing
110  E = Ty->subtype_rend();
111  I != E; ++I)
112  if (VisitedTypes.insert(*I).second)
113  TypeWorklist.push_back(*I);
114  } while (!TypeWorklist.empty());
115 }
116 
117 /// incorporateValue - This method is used to walk operand lists finding types
118 /// hiding in constant expressions and other operands that won't be walked in
119 /// other ways. GlobalValues, basic blocks, instructions, and inst operands are
120 /// all explicitly enumerated.
121 void TypeFinder::incorporateValue(const Value *V) {
122  if (const auto *M = dyn_cast<MetadataAsValue>(V)) {
123  if (const auto *N = dyn_cast<MDNode>(M->getMetadata()))
124  return incorporateMDNode(N);
125  if (const auto *MDV = dyn_cast<ValueAsMetadata>(M->getMetadata()))
126  return incorporateValue(MDV->getValue());
127  return;
128  }
129 
130  if (!isa<Constant>(V) || isa<GlobalValue>(V)) return;
131 
132  // Already visited?
133  if (!VisitedConstants.insert(V).second)
134  return;
135 
136  // Check this type.
137  incorporateType(V->getType());
138 
139  // If this is an instruction, we incorporate it separately.
140  if (isa<Instruction>(V))
141  return;
142 
143  // Look in operands for types.
144  const User *U = cast<User>(V);
145  for (const auto &I : U->operands())
146  incorporateValue(&*I);
147 }
148 
149 /// incorporateMDNode - This method is used to walk the operands of an MDNode to
150 /// find types hiding within.
151 void TypeFinder::incorporateMDNode(const MDNode *V) {
152  // Already visited?
153  if (!VisitedMetadata.insert(V).second)
154  return;
155 
156  // Look in operands for types.
157  for (Metadata *Op : V->operands()) {
158  if (!Op)
159  continue;
160  if (auto *N = dyn_cast<MDNode>(Op)) {
161  incorporateMDNode(N);
162  continue;
163  }
164  if (auto *C = dyn_cast<ConstantAsMetadata>(Op)) {
165  incorporateValue(C->getValue());
166  continue;
167  }
168  }
169 }
uint64_t CallInst * C
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:63
This file contains the declarations for metadata subclasses.
Metadata node.
Definition: Metadata.h:862
This defines the Use class.
Class to represent struct types.
Definition: DerivedTypes.h:201
A Use represents the edge between a Value definition and its users.
Definition: Use.h:56
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
op_range operands() const
Definition: Metadata.h:1065
LLVM Basic Block Representation.
Definition: BasicBlock.h:59
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
std::pair< iterator, bool > insert(const ValueT &V)
Definition: DenseSet.h:187
std::reverse_iterator< subtype_iterator > subtype_reverse_iterator
Definition: Type.h:318
op_range operands()
Definition: User.h:238
subtype_reverse_iterator subtype_rbegin() const
Definition: Type.h:320
void run(const Module &M, bool onlyNamed)
Definition: TypeFinder.cpp:32
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:861
Module.h This file contains the declarations for the Module class.
const DataFlowGraph & G
Definition: RDFGraph.cpp:211
LLVM_NODISCARD T pop_back_val()
Definition: SmallVector.h:382
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:62
subtype_reverse_iterator subtype_rend() const
Definition: Type.h:323
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
LLVM Value Representation.
Definition: Value.h:73
iterator_range< global_iterator > globals()
Definition: Module.h:566
Root of the metadata hierarchy.
Definition: Metadata.h:58
iterator_range< alias_iterator > aliases()
Definition: Module.h:606