1 //===-- llvm/CodeGen/DIEHash.h - Dwarf Hashing Framework -------*- C++ -*--===//
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 contains support for DWARF4 hashing of DIEs.
11 //
12 //===----------------------------------------------------------------------===//
14 #ifndef CODEGEN_ASMPRINTER_DIEHASH_H__
15 #define CODEGEN_ASMPRINTER_DIEHASH_H__
17 #include "DIE.h"
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/Support/MD5.h"
21 namespace llvm {
23 class AsmPrinter;
24 class CompileUnit;
26 /// \brief An object containing the capability of hashing and adding hash
27 /// attributes onto a DIE.
28 class DIEHash {
30 // The entry for a particular attribute.
31 struct AttrEntry {
32 const DIEValue *Val;
33 const DIEAbbrevData *Desc;
34 };
36 // Collection of all attributes used in hashing a particular DIE.
37 struct DIEAttrs {
38 AttrEntry DW_AT_name;
39 AttrEntry DW_AT_accessibility;
40 AttrEntry DW_AT_address_class;
41 AttrEntry DW_AT_allocated;
42 AttrEntry DW_AT_artificial;
43 AttrEntry DW_AT_associated;
44 AttrEntry DW_AT_binary_scale;
45 AttrEntry DW_AT_bit_offset;
46 AttrEntry DW_AT_bit_size;
47 AttrEntry DW_AT_bit_stride;
48 AttrEntry DW_AT_byte_size;
49 AttrEntry DW_AT_byte_stride;
50 AttrEntry DW_AT_const_expr;
51 AttrEntry DW_AT_const_value;
52 AttrEntry DW_AT_containing_type;
53 AttrEntry DW_AT_count;
54 AttrEntry DW_AT_data_bit_offset;
55 AttrEntry DW_AT_data_location;
56 AttrEntry DW_AT_data_member_location;
57 AttrEntry DW_AT_decimal_scale;
58 AttrEntry DW_AT_decimal_sign;
59 AttrEntry DW_AT_default_value;
60 AttrEntry DW_AT_digit_count;
61 AttrEntry DW_AT_discr;
62 AttrEntry DW_AT_discr_list;
63 AttrEntry DW_AT_discr_value;
64 AttrEntry DW_AT_encoding;
65 AttrEntry DW_AT_enum_class;
66 AttrEntry DW_AT_endianity;
67 AttrEntry DW_AT_explicit;
68 AttrEntry DW_AT_is_optional;
69 AttrEntry DW_AT_location;
70 AttrEntry DW_AT_lower_bound;
71 AttrEntry DW_AT_mutable;
72 AttrEntry DW_AT_ordering;
73 AttrEntry DW_AT_picture_string;
74 AttrEntry DW_AT_prototyped;
75 AttrEntry DW_AT_small;
76 AttrEntry DW_AT_segment;
77 AttrEntry DW_AT_string_length;
78 AttrEntry DW_AT_threads_scaled;
79 AttrEntry DW_AT_upper_bound;
80 AttrEntry DW_AT_use_location;
81 AttrEntry DW_AT_use_UTF8;
82 AttrEntry DW_AT_variable_parameter;
83 AttrEntry DW_AT_virtuality;
84 AttrEntry DW_AT_visibility;
85 AttrEntry DW_AT_vtable_elem_location;
86 AttrEntry DW_AT_type;
88 // Insert any additional ones here...
89 };
91 public:
92 DIEHash(AsmPrinter *A = NULL) : AP(A) {}
94 /// \brief Computes the ODR signature.
95 uint64_t computeDIEODRSignature(const DIE &Die);
97 /// \brief Computes the CU signature.
98 uint64_t computeCUSignature(const DIE &Die);
100 /// \brief Computes the type signature.
101 uint64_t computeTypeSignature(const DIE &Die);
103 // Helper routines to process parts of a DIE.
104 private:
105 /// \brief Adds the parent context of \param Die to the hash.
106 void addParentContext(const DIE &Die);
108 /// \brief Adds the attributes of \param Die to the hash.
109 void addAttributes(const DIE &Die);
111 /// \brief Computes the full DWARF4 7.27 hash of the DIE.
112 void computeHash(const DIE &Die);
114 // Routines that add DIEValues to the hash.
115 public:
116 /// \brief Adds \param Value to the hash.
117 void update(uint8_t Value) { Hash.update(Value); }
119 /// \brief Encodes and adds \param Value to the hash as a ULEB128.
120 void addULEB128(uint64_t Value);
122 /// \brief Encodes and adds \param Value to the hash as a SLEB128.
123 void addSLEB128(int64_t Value);
125 private:
126 /// \brief Adds \param Str to the hash and includes a NULL byte.
127 void addString(StringRef Str);
129 /// \brief Collects the attributes of DIE \param Die into the \param Attrs
130 /// structure.
131 void collectAttributes(const DIE &Die, DIEAttrs &Attrs);
133 /// \brief Hashes the attributes in \param Attrs in order.
134 void hashAttributes(const DIEAttrs &Attrs, dwarf::Tag Tag);
136 /// \brief Hashes the data in a block like DIEValue, e.g. DW_FORM_block or
137 /// DW_FORM_exprloc.
138 void hashBlockData(const SmallVectorImpl<DIEValue *> &Values);
140 /// \brief Hashes an individual attribute.
141 void hashAttribute(AttrEntry Attr, dwarf::Tag Tag);
143 /// \brief Hashes an attribute that refers to another DIE.
144 void hashDIEEntry(dwarf::Attribute Attribute, dwarf::Tag Tag,
145 const DIE &Entry);
147 /// \brief Hashes a reference to a named type in such a way that is
148 /// independent of whether that type is described by a declaration or a
149 /// definition.
150 void hashShallowTypeReference(dwarf::Attribute Attribute, const DIE &Entry,
151 StringRef Name);
153 /// \brief Hashes a reference to a previously referenced type DIE.
154 void hashRepeatedTypeReference(dwarf::Attribute Attribute,
155 unsigned DieNumber);
157 void hashNestedType(const DIE &Die, StringRef Name);
159 private:
160 MD5 Hash;
161 AsmPrinter *AP;
162 DenseMap<const DIE *, unsigned> Numbering;
163 };
164 }
166 #endif