LLVM  9.0.0svn
RecordSerialization.h
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1 //===- RecordSerialization.h ------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_DEBUGINFO_CODEVIEW_RECORDSERIALIZATION_H
10 #define LLVM_DEBUGINFO_CODEVIEW_RECORDSERIALIZATION_H
11 
12 #include "llvm/ADT/APSInt.h"
13 #include "llvm/ADT/ArrayRef.h"
14 #include "llvm/ADT/StringRef.h"
18 #include "llvm/Support/Endian.h"
19 #include "llvm/Support/Error.h"
20 #include <cinttypes>
21 #include <tuple>
22 
23 namespace llvm {
24 namespace codeview {
28 
29 /// Limit on the size of all codeview symbol and type records, including the
30 /// RecordPrefix. MSVC does not emit any records larger than this.
31 enum : unsigned { MaxRecordLength = 0xFF00 };
32 
33 struct RecordPrefix {
34  ulittle16_t RecordLen; // Record length, starting from &RecordKind.
35  ulittle16_t RecordKind; // Record kind enum (SymRecordKind or TypeRecordKind)
36 };
37 
38 /// Reinterpret a byte array as an array of characters. Does not interpret as
39 /// a C string, as StringRef has several helpers (split) that make that easy.
42 
43 inline Error consume(BinaryStreamReader &Reader) { return Error::success(); }
44 
45 /// Decodes a numeric "leaf" value. These are integer literals encountered in
46 /// the type stream. If the value is positive and less than LF_NUMERIC (1 <<
47 /// 15), it is emitted directly in Data. Otherwise, it has a tag like LF_CHAR
48 /// that indicates the bitwidth and sign of the numeric data.
49 Error consume(BinaryStreamReader &Reader, APSInt &Num);
50 
51 /// Decodes a numeric leaf value that is known to be a particular type.
52 Error consume_numeric(BinaryStreamReader &Reader, uint64_t &Value);
53 
54 /// Decodes signed and unsigned fixed-length integers.
56 Error consume(BinaryStreamReader &Reader, int32_t &Item);
57 
58 /// Decodes a null terminated string.
60 
62 Error consume(StringRef &Data, uint32_t &Item);
63 
64 /// Decodes an arbitrary object whose layout matches that of the underlying
65 /// byte sequence, and returns a pointer to the object.
66 template <typename T> Error consume(BinaryStreamReader &Reader, T *&Item) {
67  return Reader.readObject(Item);
68 }
69 
70 template <typename T, typename U> struct serialize_conditional_impl {
71  serialize_conditional_impl(T &Item, U Func) : Item(Item), Func(Func) {}
72 
74  if (!Func())
75  return Error::success();
76  return consume(Reader, Item);
77  }
78 
79  T &Item;
80  U Func;
81 };
82 
83 template <typename T, typename U>
85  return serialize_conditional_impl<T, U>(Item, Func);
86 }
87 
88 template <typename T, typename U> struct serialize_array_impl {
89  serialize_array_impl(ArrayRef<T> &Item, U Func) : Item(Item), Func(Func) {}
90 
92  return Reader.readArray(Item, Func());
93  }
94 
96  U Func;
97 };
98 
99 template <typename T> struct serialize_vector_tail_impl {
100  serialize_vector_tail_impl(std::vector<T> &Item) : Item(Item) {}
101 
103  T Field;
104  // Stop when we run out of bytes or we hit record padding bytes.
105  while (!Reader.empty() && Reader.peek() < LF_PAD0) {
106  if (auto EC = consume(Reader, Field))
107  return EC;
108  Item.push_back(Field);
109  }
110  return Error::success();
111  }
112 
113  std::vector<T> &Item;
114 };
115 
117  serialize_null_term_string_array_impl(std::vector<StringRef> &Item)
118  : Item(Item) {}
119 
121  if (Reader.empty())
122  return make_error<CodeViewError>(cv_error_code::insufficient_buffer,
123  "Null terminated string is empty!");
124 
125  while (Reader.peek() != 0) {
127  if (auto EC = Reader.readCString(Field))
128  return EC;
129  Item.push_back(Field);
130  }
131  return Reader.skip(1);
132  }
133 
134  std::vector<StringRef> &Item;
135 };
136 
137 template <typename T> struct serialize_arrayref_tail_impl {
139 
141  uint32_t Count = Reader.bytesRemaining() / sizeof(T);
142  return Reader.readArray(Item, Count);
143  }
144 
146 };
147 
148 template <typename T> struct serialize_numeric_impl {
149  serialize_numeric_impl(T &Item) : Item(Item) {}
150 
152  return consume_numeric(Reader, Item);
153  }
154 
155  T &Item;
156 };
157 
158 template <typename T, typename U>
160  return serialize_array_impl<T, U>(Item, Func);
161 }
162 
164 serialize_null_term_string_array(std::vector<StringRef> &Item) {
166 }
167 
168 template <typename T>
170  return serialize_vector_tail_impl<T>(Item);
171 }
172 
173 template <typename T>
175  return serialize_arrayref_tail_impl<T>(Item);
176 }
177 
178 template <typename T> serialize_numeric_impl<T> serialize_numeric(T &Item) {
179  return serialize_numeric_impl<T>(Item);
180 }
181 
182 template <typename T, typename U>
184  const serialize_conditional_impl<T, U> &Item) {
185  return Item.deserialize(Reader);
186 }
187 
188 template <typename T, typename U>
190  const serialize_array_impl<T, U> &Item) {
191  return Item.deserialize(Reader);
192 }
193 
196  return Item.deserialize(Reader);
197 }
198 
199 template <typename T>
201  const serialize_vector_tail_impl<T> &Item) {
202  return Item.deserialize(Reader);
203 }
204 
205 template <typename T>
207  const serialize_arrayref_tail_impl<T> &Item) {
208  return Item.deserialize(Reader);
209 }
210 
211 template <typename T>
213  const serialize_numeric_impl<T> &Item) {
214  return Item.deserialize(Reader);
215 }
216 
217 template <typename T, typename U, typename... Args>
218 Error consume(BinaryStreamReader &Reader, T &&X, U &&Y, Args &&... Rest) {
219  if (auto EC = consume(Reader, X))
220  return EC;
221  return consume(Reader, Y, std::forward<Args>(Rest)...);
222 }
223 
224 }
225 }
226 
227 #endif
Error deserialize(BinaryStreamReader &Reader) const
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
Error consume_numeric(BinaryStreamReader &Reader, uint64_t &Value)
Decodes a numeric leaf value that is known to be a particular type.
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Error deserialize(BinaryStreamReader &Reader) const
Error readObject(const T *&Dest)
Get a pointer to an object of type T from the underlying stream, as if by memcpy, and store the resul...
serialize_vector_tail_impl< T > serialize_array_tail(std::vector< T > &Item)
uint8_t peek() const
Examine the next byte of the underlying stream without advancing the stream&#39;s offset.
detail::packed_endian_specific_integral< uint16_t, little, unaligned > ulittle16_t
Definition: Endian.h:268
static GCMetadataPrinterRegistry::Add< OcamlGCMetadataPrinter > Y("ocaml", "ocaml 3.10-compatible collector")
serialize_array_impl(ArrayRef< T > &Item, U Func)
Error readCString(StringRef &Dest)
Read a null terminated string from Dest.
#define T
serialize_null_term_string_array_impl serialize_null_term_string_array(std::vector< StringRef > &Item)
detail::packed_endian_specific_integral< uint32_t, little, unaligned > ulittle32_t
Definition: Endian.h:270
serialize_array_impl< T, U > serialize_array(ArrayRef< T > &Item, U Func)
Error deserialize(BinaryStreamReader &Reader) const
static ErrorSuccess success()
Create a success value.
Definition: Error.h:326
Error deserialize(BinaryStreamReader &Reader) const
serialize_null_term_string_array_impl(std::vector< StringRef > &Item)
StringRef getBytesAsCharacters(ArrayRef< uint8_t > LeafData)
Reinterpret a byte array as an array of characters.
StringRef getBytesAsCString(ArrayRef< uint8_t > LeafData)
detail::packed_endian_specific_integral< int32_t, little, unaligned > little32_t
Definition: Endian.h:277
Error skip(uint32_t Amount)
Advance the stream&#39;s offset by Amount bytes.
uint32_t bytesRemaining() const
serialize_numeric_impl< T > serialize_numeric(T &Item)
Error consume(BinaryStreamReader &Reader)
Error deserialize(BinaryStreamReader &Reader) const
LLVM Value Representation.
Definition: Value.h:72
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
Provides read only access to a subclass of BinaryStream.
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
Error deserialize(BinaryStreamReader &Reader) const
serialize_conditional_impl< T, U > serialize_conditional(T &Item, U Func)
constexpr char Args[]
Key for Kernel::Metadata::mArgs.
Error readArray(ArrayRef< T > &Array, uint32_t NumElements)
Get a reference to a NumElements element array of objects of type T from the underlying stream as if ...