1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
//===--- CodeGenTBAA.h - TBAA information for LLVM CodeGen ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the code that manages TBAA information and defines the TBAA policy
// for the optimizer to use.
//
//===----------------------------------------------------------------------===//
#ifndef CLANG_CODEGEN_CODEGENTBAA_H
#define CLANG_CODEGEN_CODEGENTBAA_H
#include "clang/Basic/LLVM.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/IR/MDBuilder.h"
namespace llvm {
class LLVMContext;
class MDNode;
}
namespace clang {
class ASTContext;
class CodeGenOptions;
class LangOptions;
class MangleContext;
class QualType;
class Type;
namespace CodeGen {
class CGRecordLayout;
struct TBAAPathTag {
TBAAPathTag(const Type *B, const llvm::MDNode *A, uint64_t O)
: BaseT(B), AccessN(A), Offset(O) {}
const Type *BaseT;
const llvm::MDNode *AccessN;
uint64_t Offset;
};
/// CodeGenTBAA - This class organizes the cross-module state that is used
/// while lowering AST types to LLVM types.
class CodeGenTBAA {
ASTContext &Context;
const CodeGenOptions &CodeGenOpts;
const LangOptions &Features;
MangleContext &MContext;
// MDHelper - Helper for creating metadata.
llvm::MDBuilder MDHelper;
/// MetadataCache - This maps clang::Types to scalar llvm::MDNodes describing
/// them.
llvm::DenseMap<const Type *, llvm::MDNode *> MetadataCache;
/// This maps clang::Types to a struct node in the type DAG.
llvm::DenseMap<const Type *, llvm::MDNode *> StructTypeMetadataCache;
/// This maps TBAAPathTags to a tag node.
llvm::DenseMap<TBAAPathTag, llvm::MDNode *> StructTagMetadataCache;
/// This maps a scalar type to a scalar tag node.
llvm::DenseMap<const llvm::MDNode *, llvm::MDNode *> ScalarTagMetadataCache;
/// StructMetadataCache - This maps clang::Types to llvm::MDNodes describing
/// them for struct assignments.
llvm::DenseMap<const Type *, llvm::MDNode *> StructMetadataCache;
llvm::MDNode *Root;
llvm::MDNode *Char;
/// getRoot - This is the mdnode for the root of the metadata type graph
/// for this translation unit.
llvm::MDNode *getRoot();
/// getChar - This is the mdnode for "char", which is special, and any types
/// considered to be equivalent to it.
llvm::MDNode *getChar();
/// CollectFields - Collect information about the fields of a type for
/// !tbaa.struct metadata formation. Return false for an unsupported type.
bool CollectFields(uint64_t BaseOffset,
QualType Ty,
SmallVectorImpl<llvm::MDBuilder::TBAAStructField> &Fields,
bool MayAlias);
/// A wrapper function to create a scalar type. For struct-path aware TBAA,
/// the scalar type has the same format as the struct type: name, offset,
/// pointer to another node in the type DAG.
llvm::MDNode *createTBAAScalarType(StringRef Name, llvm::MDNode *Parent);
public:
CodeGenTBAA(ASTContext &Ctx, llvm::LLVMContext &VMContext,
const CodeGenOptions &CGO,
const LangOptions &Features,
MangleContext &MContext);
~CodeGenTBAA();
/// getTBAAInfo - Get the TBAA MDNode to be used for a dereference
/// of the given type.
llvm::MDNode *getTBAAInfo(QualType QTy);
/// getTBAAInfoForVTablePtr - Get the TBAA MDNode to be used for a
/// dereference of a vtable pointer.
llvm::MDNode *getTBAAInfoForVTablePtr();
/// getTBAAStructInfo - Get the TBAAStruct MDNode to be used for a memcpy of
/// the given type.
llvm::MDNode *getTBAAStructInfo(QualType QTy);
/// Get the MDNode in the type DAG for given struct type QType.
llvm::MDNode *getTBAAStructTypeInfo(QualType QType);
/// Get the tag MDNode for a given base type, the actual scalar access MDNode
/// and offset into the base type.
llvm::MDNode *getTBAAStructTagInfo(QualType BaseQType,
llvm::MDNode *AccessNode, uint64_t Offset);
/// Get the sclar tag MDNode for a given scalar type.
llvm::MDNode *getTBAAScalarTagInfo(llvm::MDNode *AccessNode);
};
} // end namespace CodeGen
} // end namespace clang
namespace llvm {
template<> struct DenseMapInfo<clang::CodeGen::TBAAPathTag> {
static clang::CodeGen::TBAAPathTag getEmptyKey() {
return clang::CodeGen::TBAAPathTag(
DenseMapInfo<const clang::Type *>::getEmptyKey(),
DenseMapInfo<const MDNode *>::getEmptyKey(),
DenseMapInfo<uint64_t>::getEmptyKey());
}
static clang::CodeGen::TBAAPathTag getTombstoneKey() {
return clang::CodeGen::TBAAPathTag(
DenseMapInfo<const clang::Type *>::getTombstoneKey(),
DenseMapInfo<const MDNode *>::getTombstoneKey(),
DenseMapInfo<uint64_t>::getTombstoneKey());
}
static unsigned getHashValue(const clang::CodeGen::TBAAPathTag &Val) {
return DenseMapInfo<const clang::Type *>::getHashValue(Val.BaseT) ^
DenseMapInfo<const MDNode *>::getHashValue(Val.AccessN) ^
DenseMapInfo<uint64_t>::getHashValue(Val.Offset);
}
static bool isEqual(const clang::CodeGen::TBAAPathTag &LHS,
const clang::CodeGen::TBAAPathTag &RHS) {
return LHS.BaseT == RHS.BaseT &&
LHS.AccessN == RHS.AccessN &&
LHS.Offset == RHS.Offset;
}
};
} // end namespace llvm
#endif
|
