1//===- InlineInfo.cpp -------------------------------------------*- 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#include "llvm/DebugInfo/GSYM/FileEntry.h"
10#include "llvm/DebugInfo/GSYM/FileWriter.h"
11#include "llvm/DebugInfo/GSYM/GsymReader.h"
12#include "llvm/DebugInfo/GSYM/InlineInfo.h"
13#include "llvm/Support/DataExtractor.h"
14#include <algorithm>
15#include <inttypes.h>
16
17using namespace llvm;
18using namespace gsym;
19
20
21raw_ostream &llvm::gsym::operator<<(raw_ostream &OS, const InlineInfo &II) {
22 if (!II.isValid())
23 return OS;
24 bool First = true;
25 for (auto Range : II.Ranges) {
26 if (First)
27 First = false;
28 else
29 OS << ' ';
30 OS << Range;
31 }
32 OS << " Name = " << HEX32(II.Name) << ", CallFile = " << II.CallFile
33 << ", CallLine = " << II.CallFile << '\n';
34 for (const auto &Child : II.Children)
35 OS << Child;
36 return OS;
37}
38
39static bool getInlineStackHelper(const InlineInfo &II, uint64_t Addr,
40 std::vector<const InlineInfo *> &InlineStack) {
41 if (II.Ranges.contains(Addr)) {
42 // If this is the top level that represents the concrete function,
43 // there will be no name and we shoud clear the inline stack. Otherwise
44 // we have found an inline call stack that we need to insert.
45 if (II.Name != 0)
46 InlineStack.insert(position: InlineStack.begin(), x: &II);
47 for (const auto &Child : II.Children) {
48 if (::getInlineStackHelper(II: Child, Addr, InlineStack))
49 break;
50 }
51 return !InlineStack.empty();
52 }
53 return false;
54}
55
56std::optional<InlineInfo::InlineArray>
57InlineInfo::getInlineStack(uint64_t Addr) const {
58 InlineArray Result;
59 if (getInlineStackHelper(II: *this, Addr, InlineStack&: Result))
60 return Result;
61 return std::nullopt;
62}
63
64/// Skip an InlineInfo object in the specified data at the specified offset.
65///
66/// Used during the InlineInfo::lookup() call to quickly skip child InlineInfo
67/// objects where the addres ranges isn't contained in the InlineInfo object
68/// or its children. This avoids allocations by not appending child InlineInfo
69/// objects to the InlineInfo::Children array.
70///
71/// \param Data The binary stream to read the data from.
72///
73/// \param Offset The byte offset within \a Data.
74///
75/// \param SkippedRanges If true, address ranges have already been skipped.
76
77static bool skip(DataExtractor &Data, uint64_t &Offset, bool SkippedRanges) {
78 if (!SkippedRanges) {
79 if (skipRanges(Data, Offset) == 0)
80 return false;
81 }
82 bool HasChildren = Data.getU8(offset_ptr: &Offset) != 0;
83 Data.getU32(offset_ptr: &Offset); // Skip Inline.Name.
84 Data.getULEB128(offset_ptr: &Offset); // Skip Inline.CallFile.
85 Data.getULEB128(offset_ptr: &Offset); // Skip Inline.CallLine.
86 if (HasChildren) {
87 while (skip(Data, Offset, SkippedRanges: false /* SkippedRanges */))
88 /* Do nothing */;
89 }
90 // We skipped a valid InlineInfo.
91 return true;
92}
93
94/// A Lookup helper functions.
95///
96/// Used during the InlineInfo::lookup() call to quickly only parse an
97/// InlineInfo object if the address falls within this object. This avoids
98/// allocations by not appending child InlineInfo objects to the
99/// InlineInfo::Children array and also skips any InlineInfo objects that do
100/// not contain the address we are looking up.
101///
102/// \param Data The binary stream to read the data from.
103///
104/// \param Offset The byte offset within \a Data.
105///
106/// \param BaseAddr The address that the relative address range offsets are
107/// relative to.
108
109static bool lookup(const GsymReader &GR, DataExtractor &Data, uint64_t &Offset,
110 uint64_t BaseAddr, uint64_t Addr, SourceLocations &SrcLocs,
111 llvm::Error &Err) {
112 InlineInfo Inline;
113 decodeRanges(Ranges&: Inline.Ranges, Data, BaseAddr, Offset);
114 if (Inline.Ranges.empty())
115 return true;
116 // Check if the address is contained within the inline information, and if
117 // not, quickly skip this InlineInfo object and all its children.
118 if (!Inline.Ranges.contains(Addr)) {
119 skip(Data, Offset, SkippedRanges: true /* SkippedRanges */);
120 return false;
121 }
122
123 // The address range is contained within this InlineInfo, add the source
124 // location for this InlineInfo and any children that contain the address.
125 bool HasChildren = Data.getU8(offset_ptr: &Offset) != 0;
126 Inline.Name = Data.getU32(offset_ptr: &Offset);
127 Inline.CallFile = (uint32_t)Data.getULEB128(offset_ptr: &Offset);
128 Inline.CallLine = (uint32_t)Data.getULEB128(offset_ptr: &Offset);
129 if (HasChildren) {
130 // Child address ranges are encoded relative to the first address in the
131 // parent InlineInfo object.
132 const auto ChildBaseAddr = Inline.Ranges[0].start();
133 bool Done = false;
134 while (!Done)
135 Done = lookup(GR, Data, Offset, BaseAddr: ChildBaseAddr, Addr, SrcLocs, Err);
136 }
137
138 std::optional<FileEntry> CallFile = GR.getFile(Index: Inline.CallFile);
139 if (!CallFile) {
140 Err = createStringError(EC: std::errc::invalid_argument,
141 Fmt: "failed to extract file[%" PRIu32 "]",
142 Vals: Inline.CallFile);
143 return false;
144 }
145
146 if (CallFile->Dir || CallFile->Base) {
147 SourceLocation SrcLoc;
148 SrcLoc.Name = SrcLocs.back().Name;
149 SrcLoc.Offset = SrcLocs.back().Offset;
150 SrcLoc.Dir = GR.getString(Offset: CallFile->Dir);
151 SrcLoc.Base = GR.getString(Offset: CallFile->Base);
152 SrcLoc.Line = Inline.CallLine;
153 SrcLocs.back().Name = GR.getString(Offset: Inline.Name);
154 SrcLocs.back().Offset = Addr - Inline.Ranges[0].start();
155 SrcLocs.push_back(x: SrcLoc);
156 }
157 return true;
158}
159
160llvm::Error InlineInfo::lookup(const GsymReader &GR, DataExtractor &Data,
161 uint64_t BaseAddr, uint64_t Addr,
162 SourceLocations &SrcLocs) {
163 // Call our recursive helper function starting at offset zero.
164 uint64_t Offset = 0;
165 llvm::Error Err = Error::success();
166 ::lookup(GR, Data, Offset, BaseAddr, Addr, SrcLocs, Err);
167 return Err;
168}
169
170/// Decode an InlineInfo in Data at the specified offset.
171///
172/// A local helper function to decode InlineInfo objects. This function is
173/// called recursively when parsing child InlineInfo objects.
174///
175/// \param Data The data extractor to decode from.
176/// \param Offset The offset within \a Data to decode from.
177/// \param BaseAddr The base address to use when decoding address ranges.
178/// \returns An InlineInfo or an error describing the issue that was
179/// encountered during decoding.
180static llvm::Expected<InlineInfo> decode(DataExtractor &Data, uint64_t &Offset,
181 uint64_t BaseAddr) {
182 InlineInfo Inline;
183 if (!Data.isValidOffset(offset: Offset))
184 return createStringError(EC: std::errc::io_error,
185 Fmt: "0x%8.8" PRIx64 ": missing InlineInfo address ranges data", Vals: Offset);
186 decodeRanges(Ranges&: Inline.Ranges, Data, BaseAddr, Offset);
187 if (Inline.Ranges.empty())
188 return Inline;
189 if (!Data.isValidOffsetForDataOfSize(offset: Offset, length: 1))
190 return createStringError(EC: std::errc::io_error,
191 Fmt: "0x%8.8" PRIx64 ": missing InlineInfo uint8_t indicating children",
192 Vals: Offset);
193 bool HasChildren = Data.getU8(offset_ptr: &Offset) != 0;
194 if (!Data.isValidOffsetForDataOfSize(offset: Offset, length: 4))
195 return createStringError(EC: std::errc::io_error,
196 Fmt: "0x%8.8" PRIx64 ": missing InlineInfo uint32_t for name", Vals: Offset);
197 Inline.Name = Data.getU32(offset_ptr: &Offset);
198 if (!Data.isValidOffset(offset: Offset))
199 return createStringError(EC: std::errc::io_error,
200 Fmt: "0x%8.8" PRIx64 ": missing ULEB128 for InlineInfo call file", Vals: Offset);
201 Inline.CallFile = (uint32_t)Data.getULEB128(offset_ptr: &Offset);
202 if (!Data.isValidOffset(offset: Offset))
203 return createStringError(EC: std::errc::io_error,
204 Fmt: "0x%8.8" PRIx64 ": missing ULEB128 for InlineInfo call line", Vals: Offset);
205 Inline.CallLine = (uint32_t)Data.getULEB128(offset_ptr: &Offset);
206 if (HasChildren) {
207 // Child address ranges are encoded relative to the first address in the
208 // parent InlineInfo object.
209 const auto ChildBaseAddr = Inline.Ranges[0].start();
210 while (true) {
211 llvm::Expected<InlineInfo> Child = decode(Data, Offset, BaseAddr: ChildBaseAddr);
212 if (!Child)
213 return Child.takeError();
214 // InlineInfo with empty Ranges termintes a child sibling chain.
215 if (Child.get().Ranges.empty())
216 break;
217 Inline.Children.emplace_back(args: std::move(*Child));
218 }
219 }
220 return Inline;
221}
222
223llvm::Expected<InlineInfo> InlineInfo::decode(DataExtractor &Data,
224 uint64_t BaseAddr) {
225 uint64_t Offset = 0;
226 return ::decode(Data, Offset, BaseAddr);
227}
228
229llvm::Error InlineInfo::encode(FileWriter &O, uint64_t BaseAddr) const {
230 // Users must verify the InlineInfo is valid prior to calling this funtion.
231 // We don't want to emit any InlineInfo objects if they are not valid since
232 // it will waste space in the GSYM file.
233 if (!isValid())
234 return createStringError(EC: std::errc::invalid_argument,
235 Fmt: "attempted to encode invalid InlineInfo object");
236 encodeRanges(Ranges, O, BaseAddr);
237 bool HasChildren = !Children.empty();
238 O.writeU8(Value: HasChildren);
239 O.writeU32(Value: Name);
240 O.writeULEB(Value: CallFile);
241 O.writeULEB(Value: CallLine);
242 if (HasChildren) {
243 // Child address ranges are encoded as relative to the first
244 // address in the Ranges for this object. This keeps the offsets
245 // small and allows for efficient encoding using ULEB offsets.
246 const uint64_t ChildBaseAddr = Ranges[0].start();
247 for (const auto &Child : Children) {
248 // Make sure all child address ranges are contained in the parent address
249 // ranges.
250 for (const auto &ChildRange: Child.Ranges) {
251 if (!Ranges.contains(Range: ChildRange))
252 return createStringError(EC: std::errc::invalid_argument,
253 Fmt: "child range not contained in parent");
254 }
255 llvm::Error Err = Child.encode(O, BaseAddr: ChildBaseAddr);
256 if (Err)
257 return Err;
258 }
259
260 // Terminate child sibling chain by emitting a zero. This zero will cause
261 // the decodeAll() function above to return false and stop the decoding
262 // of child InlineInfo objects that are siblings.
263 O.writeULEB(Value: 0);
264 }
265 return Error::success();
266}
267
268static uint64_t GetTotalNumChildren(const InlineInfo &II) {
269 uint64_t NumChildren = II.Children.size();
270 for (const auto &Child : II.Children)
271 NumChildren += GetTotalNumChildren(II: Child);
272 return NumChildren;
273}
274
275bool InlineInfo::operator<(const InlineInfo &RHS) const {
276 return GetTotalNumChildren(II: *this) < GetTotalNumChildren(II: RHS);
277}
278

source code of llvm/lib/DebugInfo/GSYM/InlineInfo.cpp