LLVM 20.0.0git
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
15#include "llvm/Support/Error.h"
16#include <stdint.h>
17#include <vector>
18
19namespace llvm {
20class raw_ostream;
21
22namespace gsym {
23
24class GsymReader;
25/// Inline information stores the name of the inline function along with
26/// an array of address ranges. It also stores the call file and call line
27/// that called this inline function. This allows us to unwind inline call
28/// stacks back to the inline or concrete function that called this
29/// function. Inlined functions contained in this function are stored in the
30/// "Children" variable. All address ranges must be sorted and all address
31/// ranges of all children must be contained in the ranges of this function.
32/// Any clients that encode information will need to ensure the ranges are
33/// all contined correctly or lookups could fail. Add ranges in these objects
34/// must be contained in the top level FunctionInfo address ranges as well.
35///
36/// ENCODING
37///
38/// When saved to disk, the inline info encodes all ranges to be relative to
39/// a parent address range. This will be the FunctionInfo's start address if
40/// the InlineInfo is directly contained in a FunctionInfo, or a the start
41/// address of the containing parent InlineInfo's first "Ranges" member. This
42/// allows address ranges to be efficiently encoded using ULEB128 encodings as
43/// we encode the offset and size of each range instead of full addresses. This
44/// also makes any encoded addresses easy to relocate as we just need to
45/// relocate the FunctionInfo's start address.
46///
47/// - The AddressRanges member "Ranges" is encoded using an appropriate base
48/// address as described above.
49/// - UINT8 boolean value that specifies if the InlineInfo object has children.
50/// - UINT32 string table offset that points to the name of the inline
51/// function.
52/// - ULEB128 integer that specifies the file of the call site that called
53/// this function.
54/// - ULEB128 integer that specifies the source line of the call site that
55/// called this function.
56/// - if this object has children, enocode each child InlineInfo using the
57/// the first address range's start address as the base address.
58///
59struct InlineInfo {
60
61 uint32_t Name; ///< String table offset in the string table.
62 uint32_t CallFile; ///< 1 based file index in the file table.
63 uint32_t CallLine; ///< Source line number.
65 std::vector<InlineInfo> Children;
66 InlineInfo() : Name(0), CallFile(0), CallLine(0) {}
67 void clear() {
68 Name = 0;
69 CallFile = 0;
70 CallLine = 0;
71 Ranges.clear();
72 Children.clear();
73 }
74 bool isValid() const { return !Ranges.empty(); }
75
76 using InlineArray = std::vector<const InlineInfo *>;
77
78 /// Lookup a single address within the inline info data.
79 ///
80 /// Clients have the option to decode an entire InlineInfo object (using
81 /// InlineInfo::decode() ) or just find the matching inline info using this
82 /// function. The benefit of using this function is that only the information
83 /// needed for the lookup will be extracted, other info can be skipped and
84 /// parsing can stop as soon as the deepest match is found. This allows
85 /// symbolication tools to be fast and efficient and avoid allocation costs
86 /// when doing lookups.
87 ///
88 /// This function will augment the SourceLocations array \a SrcLocs with any
89 /// inline information that pertains to \a Addr. If no inline information
90 /// exists for \a Addr, then \a SrcLocs will be left untouched. If there is
91 /// inline information for \a Addr, then \a SrcLocs will be modifiied to
92 /// contain the deepest most inline function's SourceLocation at index zero
93 /// in the array and proceed up the concrete function source file and
94 /// line at the end of the array.
95 ///
96 /// \param GR The GSYM reader that contains the string and file table that
97 /// will be used to fill in the source locations.
98 ///
99 /// \param Data The binary stream to read the data from. This object must
100 /// have the data for the LineTable object starting at offset zero. The data
101 /// can contain more data than needed.
102 ///
103 /// \param BaseAddr The base address to use when decoding the line table.
104 /// This will be the FunctionInfo's start address and will be used to
105 /// decode the correct addresses for the inline information.
106 ///
107 /// \param Addr The address to lookup.
108 ///
109 /// \param SrcLocs The inline source locations that matches \a Addr. This
110 /// array must be initialized with the matching line entry
111 /// from the line table upon entry. The name of the concrete
112 /// function must be supplied since it will get pushed to
113 /// the last SourceLocation entry and the inline information
114 /// will fill in the source file and line from the inline
115 /// information.
116 ///
117 /// \returns An error if the inline information is corrupt, or
118 /// Error::success() for all other cases, even when no information
119 /// is added to \a SrcLocs.
121 uint64_t BaseAddr, uint64_t Addr,
122 SourceLocations &SrcLocs);
123
124 /// Lookup an address in the InlineInfo object
125 ///
126 /// This function is used to symbolicate an inline call stack and can
127 /// turn one address in the program into one or more inline call stacks
128 /// and have the stack trace show the original call site from
129 /// non-inlined code.
130 ///
131 /// \param Addr the address to lookup
132 ///
133 /// \returns optional vector of InlineInfo objects that describe the
134 /// inline call stack for a given address, false otherwise.
135 std::optional<InlineArray> getInlineStack(uint64_t Addr) const;
136
137 /// Decode an InlineInfo object from a binary data stream.
138 ///
139 /// \param Data The binary stream to read the data from. This object must
140 /// have the data for the InlineInfo object starting at offset zero. The data
141 /// can contain more data than needed.
142 ///
143 /// \param BaseAddr The base address to use when decoding all address ranges.
144 /// This will be the FunctionInfo's start address if this object is directly
145 /// contained in a FunctionInfo object, or the start address of the first
146 /// address range in an InlineInfo object of this object is a child of
147 /// another InlineInfo object.
148 /// \returns An InlineInfo or an error describing the issue that was
149 /// encountered during decoding.
151 uint64_t BaseAddr);
152
153 /// Encode this InlineInfo object into FileWriter stream.
154 ///
155 /// \param O The binary stream to write the data to at the current file
156 /// position.
157 ///
158 /// \param BaseAddr The base address to use when encoding all address ranges.
159 /// This will be the FunctionInfo's start address if this object is directly
160 /// contained in a FunctionInfo object, or the start address of the first
161 /// address range in an InlineInfo object of this object is a child of
162 /// another InlineInfo object.
163 ///
164 /// \returns An error object that indicates success or failure or the
165 /// encoding process.
166 llvm::Error encode(FileWriter &O, uint64_t BaseAddr) const;
167
168 /// Compare InlineInfo objects.
169 ///
170 /// When comparing InlineInfo objects the item with the most inline functions
171 /// wins. If we have two FunctionInfo objects that both have the same address
172 /// range and both have valid InlineInfo objects, we want the one with the
173 /// most inline functions to win so we save the most information possible
174 /// to the GSYM file. We have seen cases where LTO messes up the inline
175 /// function information for the same address range, so this helps ensure we
176 /// get the most descriptive information we can for an address range.
177 bool operator<(const InlineInfo &RHS) const;
178};
179
180inline bool operator==(const InlineInfo &LHS, const InlineInfo &RHS) {
181 return LHS.Name == RHS.Name && LHS.CallFile == RHS.CallFile &&
182 LHS.CallLine == RHS.CallLine && LHS.Ranges == RHS.Ranges &&
183 LHS.Children == RHS.Children;
184}
185
186raw_ostream &operator<<(raw_ostream &OS, const InlineInfo &FI);
187
188} // namespace gsym
189} // namespace llvm
190
191#endif // LLVM_DEBUGINFO_GSYM_INLINEINFO_H
uint64_t Addr
raw_pwrite_stream & OS
Value * RHS
Value * LHS
The AddressRanges class helps normalize address range collections.
Lightweight error class with error context and mandatory checking.
Definition: Error.h:160
Tagged union holding either a T or a Error.
Definition: Error.h:481
A simplified binary data writer class that doesn't require targets, target definitions,...
Definition: FileWriter.h:29
GsymReader is used to read GSYM data from a file or buffer.
Definition: GsymReader.h:44
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
raw_ostream & operator<<(raw_ostream &OS, const FunctionInfo &R)
std::vector< SourceLocation > SourceLocations
Definition: LookupResult.h:36
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
bool operator==(const AddressRangeValuePair &LHS, const AddressRangeValuePair &RHS)
Inline information stores the name of the inline function along with an array of address ranges.
Definition: InlineInfo.h:59
bool operator<(const InlineInfo &RHS) const
Compare InlineInfo objects.
Definition: InlineInfo.cpp:275
std::vector< InlineInfo > Children
Definition: InlineInfo.h:65
AddressRanges Ranges
Definition: InlineInfo.h:64
std::vector< const InlineInfo * > InlineArray
Definition: InlineInfo.h:76
std::optional< InlineArray > getInlineStack(uint64_t Addr) const
Lookup an address in the InlineInfo object.
Definition: InlineInfo.cpp:57
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:160
uint32_t CallFile
1 based file index in the file table.
Definition: InlineInfo.h:62
bool isValid() const
Definition: InlineInfo.h:74
llvm::Error encode(FileWriter &O, uint64_t BaseAddr) const
Encode this InlineInfo object into FileWriter stream.
Definition: InlineInfo.cpp:229
uint32_t CallLine
Source line number.
Definition: InlineInfo.h:63
static llvm::Expected< InlineInfo > decode(DataExtractor &Data, uint64_t BaseAddr)
Decode an InlineInfo object from a binary data stream.
Definition: InlineInfo.cpp:223
uint32_t Name
String table offset in the string table.
Definition: InlineInfo.h:61