LLVM  12.0.0git
InlineInfo.h
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1 //===- InlineInfo.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_GSYM_INLINEINFO_H
10 #define LLVM_DEBUGINFO_GSYM_INLINEINFO_H
11 
12 #include "llvm/ADT/Optional.h"
16 #include "llvm/Support/Error.h"
17 #include <stdint.h>
18 #include <vector>
19 
20 
21 namespace llvm {
22 class raw_ostream;
23 
24 namespace gsym {
25 
26 class GsymReader;
27 /// Inline information stores the name of the inline function along with
28 /// an array of address ranges. It also stores the call file and call line
29 /// that called this inline function. This allows us to unwind inline call
30 /// stacks back to the inline or concrete function that called this
31 /// function. Inlined functions contained in this function are stored in the
32 /// "Children" variable. All address ranges must be sorted and all address
33 /// ranges of all children must be contained in the ranges of this function.
34 /// Any clients that encode information will need to ensure the ranges are
35 /// all contined correctly or lookups could fail. Add ranges in these objects
36 /// must be contained in the top level FunctionInfo address ranges as well.
37 ///
38 /// ENCODING
39 ///
40 /// When saved to disk, the inline info encodes all ranges to be relative to
41 /// a parent address range. This will be the FunctionInfo's start address if
42 /// the InlineInfo is directly contained in a FunctionInfo, or a the start
43 /// address of the containing parent InlineInfo's first "Ranges" member. This
44 /// allows address ranges to be efficiently encoded using ULEB128 encodings as
45 /// we encode the offset and size of each range instead of full addresses. This
46 /// also makes any encoded addresses easy to relocate as we just need to
47 /// relocate the FunctionInfo's start address.
48 ///
49 /// - The AddressRanges member "Ranges" is encoded using an appropriate base
50 /// address as described above.
51 /// - UINT8 boolean value that specifies if the InlineInfo object has children.
52 /// - UINT32 string table offset that points to the name of the inline
53 /// function.
54 /// - ULEB128 integer that specifies the file of the call site that called
55 /// this function.
56 /// - ULEB128 integer that specifies the source line of the call site that
57 /// called this function.
58 /// - if this object has children, enocode each child InlineInfo using the
59 /// the first address range's start address as the base address.
60 ///
61 struct InlineInfo {
62 
63  uint32_t Name; ///< String table offset in the string table.
64  uint32_t CallFile; ///< 1 based file index in the file table.
65  uint32_t CallLine; ///< Source line number.
67  std::vector<InlineInfo> Children;
68  InlineInfo() : Name(0), CallFile(0), CallLine(0) {}
69  void clear() {
70  Name = 0;
71  CallFile = 0;
72  CallLine = 0;
73  Ranges.clear();
74  Children.clear();
75  }
76  bool isValid() const { return !Ranges.empty(); }
77 
78  using InlineArray = std::vector<const InlineInfo *>;
79 
80  /// Lookup a single address within the inline info data.
81  ///
82  /// Clients have the option to decode an entire InlineInfo object (using
83  /// InlineInfo::decode() ) or just find the matching inline info using this
84  /// function. The benefit of using this function is that only the information
85  /// needed for the lookup will be extracted, other info can be skipped and
86  /// parsing can stop as soon as the deepest match is found. This allows
87  /// symbolication tools to be fast and efficient and avoid allocation costs
88  /// when doing lookups.
89  ///
90  /// This function will augment the SourceLocations array \a SrcLocs with any
91  /// inline information that pertains to \a Addr. If no inline information
92  /// exists for \a Addr, then \a SrcLocs will be left untouched. If there is
93  /// inline information for \a Addr, then \a SrcLocs will be modifiied to
94  /// contain the deepest most inline function's SourceLocation at index zero
95  /// in the array and proceed up the the concrete function source file and
96  /// line at the end of the array.
97  ///
98  /// \param GR The GSYM reader that contains the string and file table that
99  /// will be used to fill in the source locations.
100  ///
101  /// \param Data The binary stream to read the data from. This object must
102  /// have the data for the LineTable object starting at offset zero. The data
103  /// can contain more data than needed.
104  ///
105  /// \param BaseAddr The base address to use when decoding the line table.
106  /// This will be the FunctionInfo's start address and will be used to
107  /// decode the correct addresses for the inline information.
108  ///
109  /// \param Addr The address to lookup.
110  ///
111  /// \param SrcLocs The inline source locations that matches \a Addr. This
112  /// array must be initialized with the matching line entry
113  /// from the line table upon entry. The name of the concrete
114  /// function must be supplied since it will get pushed to
115  /// the last SourceLocation entry and the inline information
116  /// will fill in the source file and line from the inline
117  /// information.
118  ///
119  /// \returns An error if the inline information is corrupt, or
120  /// Error::success() for all other cases, even when no information
121  /// is added to \a SrcLocs.
122  static llvm::Error lookup(const GsymReader &GR, DataExtractor &Data,
123  uint64_t BaseAddr, uint64_t Addr,
124  SourceLocations &SrcLocs);
125 
126  /// Lookup an address in the InlineInfo object
127  ///
128  /// This function is used to symbolicate an inline call stack and can
129  /// turn one address in the program into one or more inline call stacks
130  /// and have the stack trace show the original call site from
131  /// non-inlined code.
132  ///
133  /// \param Addr the address to lookup
134  ///
135  /// \returns optional vector of InlineInfo objects that describe the
136  /// inline call stack for a given address, false otherwise.
137  llvm::Optional<InlineArray> getInlineStack(uint64_t Addr) const;
138 
139  /// Decode an InlineInfo object from a binary data stream.
140  ///
141  /// \param Data The binary stream to read the data from. This object must
142  /// have the data for the InlineInfo object starting at offset zero. The data
143  /// can contain more data than needed.
144  ///
145  /// \param BaseAddr The base address to use when decoding all address ranges.
146  /// This will be the FunctionInfo's start address if this object is directly
147  /// contained in a FunctionInfo object, or the start address of the first
148  /// address range in an InlineInfo object of this object is a child of
149  /// another InlineInfo object.
150  /// \returns An InlineInfo or an error describing the issue that was
151  /// encountered during decoding.
153  uint64_t BaseAddr);
154 
155  /// Encode this InlineInfo object into FileWriter stream.
156  ///
157  /// \param O The binary stream to write the data to at the current file
158  /// position.
159  ///
160  /// \param BaseAddr The base address to use when encoding all address ranges.
161  /// This will be the FunctionInfo's start address if this object is directly
162  /// contained in a FunctionInfo object, or the start address of the first
163  /// address range in an InlineInfo object of this object is a child of
164  /// another InlineInfo object.
165  ///
166  /// \returns An error object that indicates success or failure or the
167  /// encoding process.
168  llvm::Error encode(FileWriter &O, uint64_t BaseAddr) const;
169 };
170 
171 inline bool operator==(const InlineInfo &LHS, const InlineInfo &RHS) {
172  return LHS.Name == RHS.Name && LHS.CallFile == RHS.CallFile &&
173  LHS.CallLine == RHS.CallLine && LHS.Ranges == RHS.Ranges &&
174  LHS.Children == RHS.Children;
175 }
176 
178 
179 } // namespace gsym
180 } // namespace llvm
181 
182 #endif // #ifndef LLVM_DEBUGINFO_GSYM_INLINEINFO_H
GsymReader is used to read GSYM data from a file or buffer.
Definition: GsymReader.h:47
static llvm::Error lookup(const GsymReader &GR, DataExtractor &Data, uint64_t BaseAddr, uint64_t Addr, SourceLocations &SrcLocs)
Lookup a single address within the inline info data.
Definition: InlineInfo.cpp:159
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Inline information stores the name of the inline function along with an array of address ranges...
Definition: InlineInfo.h:61
The AddressRanges class helps normalize address range collections.
Definition: Range.h:84
uint32_t Name
String table offset in the string table.
Definition: InlineInfo.h:63
Tagged union holding either a T or a Error.
Definition: APFloat.h:42
std::vector< InlineInfo > Children
Definition: InlineInfo.h:67
llvm::Optional< InlineArray > getInlineStack(uint64_t Addr) const
Lookup an address in the InlineInfo object.
Definition: InlineInfo.cpp:56
A simplified binary data writer class that doesn&#39;t require targets, target definitions, architectures, or require any other optional compile time libraries to be enabled via the build process.
Definition: FileWriter.h:29
bool empty() const
Definition: Range.h:90
static llvm::Expected< InlineInfo > decode(DataExtractor &Data, uint64_t BaseAddr)
Decode an InlineInfo object from a binary data stream.
Definition: InlineInfo.cpp:222
std::vector< const InlineInfo * > InlineArray
Definition: InlineInfo.h:78
uint32_t CallFile
1 based file index in the file table.
Definition: InlineInfo.h:64
bool operator==(const FunctionInfo &LHS, const FunctionInfo &RHS)
Definition: FunctionInfo.h:187
AddressRanges Ranges
Definition: InlineInfo.h:66
std::vector< SourceLocation > SourceLocations
Definition: LookupResult.h:38
uint32_t CallLine
Source line number.
Definition: InlineInfo.h:65
bool isValid() const
Definition: InlineInfo.h:76
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:46
llvm::Error encode(FileWriter &O, uint64_t BaseAddr) const
Encode this InlineInfo object into FileWriter stream.
Definition: InlineInfo.cpp:228
raw_ostream & operator<<(raw_ostream &OS, const FunctionInfo &R)