blob: d0d8f984a9efaed712cfa17535e08626633532bd (
plain)
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
|
//===--- CGRecordLayout.h - LLVM Record Layout Information ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef CLANG_CODEGEN_CGRECORDLAYOUT_H
#define CLANG_CODEGEN_CGRECORDLAYOUT_H
#include "llvm/ADT/DenseMap.h"
#include "clang/AST/Decl.h"
namespace llvm {
class Type;
}
namespace clang {
namespace CodeGen {
/// CGRecordLayout - This class handles struct and union layout info while
/// lowering AST types to LLVM types.
///
/// These layout objects are only created on demand as IR generation requires.
class CGRecordLayout {
friend class CodeGenTypes;
CGRecordLayout(const CGRecordLayout&); // DO NOT IMPLEMENT
void operator=(const CGRecordLayout&); // DO NOT IMPLEMENT
public:
struct BitFieldInfo {
BitFieldInfo(unsigned FieldNo,
unsigned Start,
unsigned Size)
: FieldNo(FieldNo), Start(Start), Size(Size) {}
unsigned FieldNo;
unsigned Start;
unsigned Size;
};
private:
/// The LLVMType corresponding to this record layout.
const llvm::Type *LLVMType;
/// Map from (non-bit-field) struct field to the corresponding llvm struct
/// type field no. This info is populated by record builder.
llvm::DenseMap<const FieldDecl *, unsigned> FieldInfo;
/// Map from (bit-field) struct field to the corresponding llvm struct type
/// field no. This info is populated by record builder.
llvm::DenseMap<const FieldDecl *, BitFieldInfo> BitFields;
/// Whether one of the fields in this record layout is a pointer to data
/// member, or a struct that contains pointer to data member.
bool ContainsPointerToDataMember : 1;
public:
CGRecordLayout(const llvm::Type *T, bool ContainsPointerToDataMember)
: LLVMType(T), ContainsPointerToDataMember(ContainsPointerToDataMember) {}
/// \brief Return the LLVM type associated with this record.
const llvm::Type *getLLVMType() const {
return LLVMType;
}
/// \brief Check whether this struct contains pointers to data members.
bool containsPointerToDataMember() const {
return ContainsPointerToDataMember;
}
/// \brief Return the BitFieldInfo that corresponds to the field FD.
unsigned getLLVMFieldNo(const FieldDecl *FD) const {
assert(!FD->isBitField() && "Invalid call for bit-field decl!");
assert(FieldInfo.count(FD) && "Invalid field for record!");
return FieldInfo.lookup(FD);
}
/// \brief Return llvm::StructType element number that corresponds to the
/// field FD.
const BitFieldInfo &getBitFieldInfo(const FieldDecl *FD) const {
assert(FD->isBitField() && "Invalid call for non bit-field decl!");
llvm::DenseMap<const FieldDecl *, BitFieldInfo>::const_iterator
it = BitFields.find(FD);
assert(it != BitFields.end() && "Unable to find bitfield info");
return it->second;
}
};
} // end namespace CodeGen
} // end namespace clang
#endif
|
