xref: /llvm-project/llvm/unittests/tools/llvm-cfi-verify/GraphBuilder.cpp (revision c15bdf5598154277d21cae47cf8dae25b44398ef)
1 //===- llvm/unittests/llvm-cfi-verify/GraphBuilder.cpp --------------===//
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 #include "../tools/llvm-cfi-verify/lib/GraphBuilder.h"
11 #include "../tools/llvm-cfi-verify/lib/FileAnalysis.h"
12 #include "gmock/gmock.h"
13 #include "gtest/gtest.h"
14 
15 #include "llvm/BinaryFormat/ELF.h"
16 #include "llvm/MC/MCAsmInfo.h"
17 #include "llvm/MC/MCContext.h"
18 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
19 #include "llvm/MC/MCInst.h"
20 #include "llvm/MC/MCInstPrinter.h"
21 #include "llvm/MC/MCInstrAnalysis.h"
22 #include "llvm/MC/MCInstrDesc.h"
23 #include "llvm/MC/MCInstrInfo.h"
24 #include "llvm/MC/MCObjectFileInfo.h"
25 #include "llvm/MC/MCRegisterInfo.h"
26 #include "llvm/MC/MCSubtargetInfo.h"
27 #include "llvm/Object/Binary.h"
28 #include "llvm/Object/COFF.h"
29 #include "llvm/Object/ELFObjectFile.h"
30 #include "llvm/Object/ObjectFile.h"
31 #include "llvm/Support/Casting.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/Error.h"
34 #include "llvm/Support/MemoryBuffer.h"
35 #include "llvm/Support/TargetRegistry.h"
36 #include "llvm/Support/TargetSelect.h"
37 #include "llvm/Support/raw_ostream.h"
38 
39 #include <cstdlib>
40 #include <sstream>
41 
42 using Instr = ::llvm::cfi_verify::FileAnalysis::Instr;
43 using ::testing::AllOf;
44 using ::testing::Each;
45 using ::testing::ElementsAre;
46 using ::testing::Eq;
47 using ::testing::Field;
48 using ::testing::IsEmpty;
49 using ::testing::Matches;
50 using ::testing::Pair;
51 using ::testing::PrintToString;
52 using ::testing::Property;
53 using ::testing::SizeIs;
54 using ::testing::UnorderedElementsAre;
55 using ::testing::Value;
56 
57 namespace llvm {
58 namespace cfi_verify {
59 // Printing helpers for gtest.
60 std::string HexStringifyContainer(const std::vector<uint64_t> &C) {
61   std::stringstream Stream;
62   if (C.empty()) {
63     return "{ }";
64   }
65 
66   Stream << "{ ";
67   const auto &LastElemIt = std::end(C) - 1;
68 
69   for (auto It = std::begin(C); It != LastElemIt; ++It) {
70     Stream << "0x" << std::hex << *It << ", ";
71   }
72   Stream << "0x" << std::hex << *LastElemIt << " }";
73   return Stream.str();
74 }
75 
76 void PrintTo(const ConditionalBranchNode &BranchNode, ::std::ostream *os) {
77   *os << "ConditionalBranchNode<Address: 0x" << std::hex << BranchNode.Address
78       << ", Target: 0x" << BranchNode.Target << ", Fallthrough: 0x"
79       << BranchNode.Fallthrough
80       << ", CFIProtection: " << BranchNode.CFIProtection << ">";
81 }
82 
83 void PrintTo(const GraphResult &Result, ::std::ostream *os) {
84   *os << "Result BaseAddress: 0x" << std::hex << Result.BaseAddress << "\n";
85 
86   if (Result.ConditionalBranchNodes.empty())
87     *os << "  (No conditional branch nodes)\n";
88 
89   for (const auto &Node : Result.ConditionalBranchNodes) {
90     *os << "  ";
91     PrintTo(Node, os);
92     *os << "\n    Fallthrough Path: " << std::hex
93         << HexStringifyContainer(Result.flattenAddress(Node.Fallthrough))
94         << "\n";
95     *os << "    Target Path: " << std::hex
96         << HexStringifyContainer(Result.flattenAddress(Node.Target)) << "\n";
97   }
98 
99   if (Result.OrphanedNodes.empty())
100     *os << "  (No orphaned nodes)";
101 
102   for (const auto &Orphan : Result.OrphanedNodes) {
103     *os << "  Orphan (0x" << std::hex << Orphan
104         << ") Path: " << HexStringifyContainer(Result.flattenAddress(Orphan))
105         << "\n";
106   }
107 }
108 
109 namespace {
110 class ELFx86TestFileAnalysis : public FileAnalysis {
111 public:
112   ELFx86TestFileAnalysis()
113       : FileAnalysis(Triple("x86_64--"), SubtargetFeatures()) {}
114 
115   // Expose this method publicly for testing.
116   void parseSectionContents(ArrayRef<uint8_t> SectionBytes,
117                             uint64_t SectionAddress) {
118     FileAnalysis::parseSectionContents(SectionBytes, SectionAddress);
119   }
120 
121   Error initialiseDisassemblyMembers() {
122     return FileAnalysis::initialiseDisassemblyMembers();
123   }
124 };
125 
126 class BasicGraphBuilderTest : public ::testing::Test {
127 protected:
128   virtual void SetUp() {
129     IgnoreDWARFFlag = true;
130     SuccessfullyInitialised = true;
131     if (auto Err = Analysis.initialiseDisassemblyMembers()) {
132       handleAllErrors(std::move(Err), [&](const UnsupportedDisassembly &E) {
133         SuccessfullyInitialised = false;
134         outs()
135             << "Note: CFIVerifyTests are disabled due to lack of x86 support "
136                "on this build.\n";
137       });
138     }
139   }
140 
141   bool SuccessfullyInitialised;
142   ELFx86TestFileAnalysis Analysis;
143 };
144 
145 MATCHER_P2(HasPath, Result, Matcher, "has path " + PrintToString(Matcher)) {
146   const auto &Path = Result.flattenAddress(arg);
147   *result_listener << "the path is " << PrintToString(Path);
148   return Matches(Matcher)(Path);
149 }
150 
151 TEST_F(BasicGraphBuilderTest, BuildFlowGraphTestSinglePathFallthroughUd2) {
152   if (!SuccessfullyInitialised)
153     return;
154   Analysis.parseSectionContents(
155       {
156           0x75, 0x02, // 0: jne 4 [+2]
157           0x0f, 0x0b, // 2: ud2
158           0xff, 0x10, // 4: callq *(%rax)
159       },
160       0xDEADBEEF);
161   const auto Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 4);
162 
163   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
164   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(1));
165   EXPECT_THAT(Result.ConditionalBranchNodes,
166               Each(Field(&ConditionalBranchNode::CFIProtection, Eq(true))));
167   EXPECT_THAT(
168       Result.ConditionalBranchNodes,
169       Contains(AllOf(Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
170                      Field(&ConditionalBranchNode::Target,
171                            HasPath(Result, ElementsAre(0xDEADBEEF + 4))),
172                      Field(&ConditionalBranchNode::Fallthrough,
173                            HasPath(Result, ElementsAre(0xDEADBEEF + 2))))))
174       << PrintToString(Result);
175 }
176 
177 TEST_F(BasicGraphBuilderTest, BuildFlowGraphTestSinglePathJumpUd2) {
178   if (!SuccessfullyInitialised)
179     return;
180   Analysis.parseSectionContents(
181       {
182           0x75, 0x02, // 0: jne 4 [+2]
183           0xff, 0x10, // 2: callq *(%rax)
184           0x0f, 0x0b, // 4: ud2
185       },
186       0xDEADBEEF);
187   const auto Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 2);
188 
189   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
190   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(1));
191   EXPECT_THAT(Result.ConditionalBranchNodes,
192               Each(Field(&ConditionalBranchNode::CFIProtection, Eq(true))));
193   EXPECT_THAT(
194       Result.ConditionalBranchNodes,
195       Contains(AllOf(Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
196                      Field(&ConditionalBranchNode::Target,
197                            HasPath(Result, ElementsAre(0xDEADBEEF + 4))),
198                      Field(&ConditionalBranchNode::Fallthrough,
199                            HasPath(Result, ElementsAre(0xDEADBEEF + 2))))))
200       << PrintToString(Result);
201 }
202 
203 TEST_F(BasicGraphBuilderTest, BuildFlowGraphTestDualPathDualUd2) {
204   if (!SuccessfullyInitialised)
205     return;
206   Analysis.parseSectionContents(
207       {
208           0x75, 0x03, // 0: jne 5 [+3]
209           0x90,       // 2: nop
210           0xff, 0x10, // 3: callq *(%rax)
211           0x0f, 0x0b, // 5: ud2
212           0x75, 0xf9, // 7: jne 2 [-7]
213           0x0f, 0x0b, // 9: ud2
214       },
215       0xDEADBEEF);
216   const auto Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 3);
217 
218   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
219   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(2));
220   EXPECT_THAT(Result.ConditionalBranchNodes,
221               Each(Field(&ConditionalBranchNode::CFIProtection, Eq(true))));
222   EXPECT_THAT(
223       Result.ConditionalBranchNodes,
224       Contains(AllOf(
225           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
226           Field(&ConditionalBranchNode::Fallthrough,
227                 HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF + 3))),
228           Field(&ConditionalBranchNode::Target,
229                 HasPath(Result, ElementsAre(0xDEADBEEF + 5))))))
230       << PrintToString(Result);
231   EXPECT_THAT(
232       Result.ConditionalBranchNodes,
233       Contains(AllOf(
234           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF + 7)),
235           Field(&ConditionalBranchNode::Fallthrough,
236                 HasPath(Result, ElementsAre(0xDEADBEEF + 9))),
237           Field(&ConditionalBranchNode::Target,
238                 HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF + 3))))))
239       << PrintToString(Result);
240 }
241 
242 TEST_F(BasicGraphBuilderTest, BuildFlowGraphTestDualPathSingleUd2) {
243   if (!SuccessfullyInitialised)
244     return;
245   Analysis.parseSectionContents(
246       {
247           0x75, 0x05, // 0: jne 7 [+5]
248           0x90,       // 2: nop
249           0xff, 0x10, // 3: callq *(%rax)
250           0x75, 0xfb, // 5: jne 2 [-5]
251           0x0f, 0x0b, // 7: ud2
252       },
253       0xDEADBEEF);
254   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 3);
255 
256   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
257   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(2));
258   EXPECT_THAT(Result.ConditionalBranchNodes,
259               Each(Field(&ConditionalBranchNode::CFIProtection, Eq(true))));
260   EXPECT_THAT(
261       Result.ConditionalBranchNodes,
262       Contains(AllOf(
263           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
264           Field(&ConditionalBranchNode::Fallthrough,
265                 HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF + 3))),
266           Field(&ConditionalBranchNode::Target,
267                 HasPath(Result, ElementsAre(0xDEADBEEF + 7))))))
268       << PrintToString(Result);
269   EXPECT_THAT(
270       Result.ConditionalBranchNodes,
271       Contains(AllOf(
272           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF + 5)),
273           Field(&ConditionalBranchNode::Fallthrough,
274                 HasPath(Result, ElementsAre(0xDEADBEEF + 7))),
275           Field(&ConditionalBranchNode::Target,
276                 HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF + 3))))))
277       << PrintToString(Result);
278 }
279 
280 TEST_F(BasicGraphBuilderTest, BuildFlowGraphFailures) {
281   if (!SuccessfullyInitialised)
282     return;
283   Analysis.parseSectionContents(
284       {
285           0x90,       // 0: nop
286           0x75, 0xfe, // 1: jne 1 [-2]
287       },
288       0xDEADBEEF);
289   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF);
290   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
291   EXPECT_THAT(Result.ConditionalBranchNodes, IsEmpty());
292 
293   Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 1);
294   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
295   EXPECT_THAT(Result.ConditionalBranchNodes, IsEmpty());
296 
297   Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADC0DE);
298   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
299   EXPECT_THAT(Result.ConditionalBranchNodes, IsEmpty());
300 }
301 
302 TEST_F(BasicGraphBuilderTest, BuildFlowGraphNoXrefs) {
303   if (!SuccessfullyInitialised)
304     return;
305   Analysis.parseSectionContents(
306       {
307           0xeb, 0xfe, // 0: jmp 0 [-2]
308           0xff, 0x10, // 2: callq *(%rax)
309       },
310       0xDEADBEEF);
311   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 2);
312   EXPECT_THAT(Result.ConditionalBranchNodes, IsEmpty());
313   EXPECT_THAT(Result.OrphanedNodes, ElementsAre(0xDEADBEEF + 2));
314   EXPECT_THAT(Result.IntermediateNodes, IsEmpty());
315 }
316 
317 TEST_F(BasicGraphBuilderTest, BuildFlowGraphConditionalInfiniteLoop) {
318   if (!SuccessfullyInitialised)
319     return;
320   Analysis.parseSectionContents(
321       {
322           0x75, 0xfe, // 0: jne 0 [-2]
323           0xff, 0x10, // 2: callq *(%rax)
324       },
325       0xDEADBEEF);
326   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 2);
327   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
328   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(1));
329   EXPECT_THAT(
330       Result.ConditionalBranchNodes,
331       Each(AllOf(Field(&ConditionalBranchNode::CFIProtection, Eq(false)),
332                  Field(&ConditionalBranchNode::Target,
333                        HasPath(Result, ElementsAre(0xDEADBEEF))),
334                  Field(&ConditionalBranchNode::Fallthrough,
335                        HasPath(Result, ElementsAre(0xDEADBEEF + 2))))))
336       << PrintToString(Result);
337 }
338 
339 TEST_F(BasicGraphBuilderTest, BuildFlowGraphUnconditionalInfiniteLoop) {
340   if (!SuccessfullyInitialised)
341     return;
342   Analysis.parseSectionContents(
343       {
344           0x75, 0x02, // 0: jne 4 [+2]
345           0xeb, 0xfc, // 2: jmp 0 [-4]
346           0xff, 0x10, // 4: callq *(%rax)
347       },
348       0xDEADBEEF);
349   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 4);
350   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
351   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(1));
352   EXPECT_THAT(
353       Result.ConditionalBranchNodes,
354       Contains(
355           AllOf(Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
356                 Field(&ConditionalBranchNode::Fallthrough,
357                       HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF))),
358                 Field(&ConditionalBranchNode::Target,
359                       HasPath(Result, ElementsAre(0xDEADBEEF + 4))))))
360       << PrintToString(Result);
361 }
362 
363 TEST_F(BasicGraphBuilderTest, BuildFlowGraphNoFlowsToIndirection) {
364   if (!SuccessfullyInitialised)
365     return;
366   Analysis.parseSectionContents(
367       {
368           0x75, 0x00, // 0: jne 2 [+0]
369           0xeb, 0xfc, // 2: jmp 0 [-4]
370           0xff, 0x10, // 4: callq *(%rax)
371       },
372       0xDEADBEEF);
373   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 4);
374   EXPECT_THAT(Result.OrphanedNodes, ElementsAre(0xDEADBEEF + 4));
375   EXPECT_THAT(Result.ConditionalBranchNodes, IsEmpty());
376 }
377 
378 TEST_F(BasicGraphBuilderTest, BuildFlowGraphLengthExceededUpwards) {
379   if (!SuccessfullyInitialised)
380     return;
381   Analysis.parseSectionContents(
382       {
383           0x75, 0x06, // 0: jne 8 [+6]
384           0x90,       // 2: nop
385           0x90,       // 3: nop
386           0x90,       // 4: nop
387           0x90,       // 5: nop
388           0xff, 0x10, // 6: callq *(%rax)
389           0x0f, 0x0b, // 8: ud2
390       },
391       0xDEADBEEF);
392   uint64_t PrevSearchLengthForConditionalBranch =
393       SearchLengthForConditionalBranch;
394   SearchLengthForConditionalBranch = 2;
395 
396   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 6);
397   EXPECT_THAT(Result.OrphanedNodes, SizeIs(1));
398   EXPECT_THAT(Result.OrphanedNodes,
399               Each(HasPath(Result, ElementsAre(0xDEADBEEF + 4, 0xDEADBEEF + 5,
400                                                0xDEADBEEF + 6))))
401       << PrintToString(Result);
402   EXPECT_THAT(Result.ConditionalBranchNodes, IsEmpty());
403 
404   SearchLengthForConditionalBranch = PrevSearchLengthForConditionalBranch;
405 }
406 
407 TEST_F(BasicGraphBuilderTest, BuildFlowGraphLengthExceededDownwards) {
408   if (!SuccessfullyInitialised)
409     return;
410   Analysis.parseSectionContents(
411       {
412           0x75, 0x02, // 0: jne 4 [+2]
413           0xff, 0x10, // 2: callq *(%rax)
414           0x90,       // 4: nop
415           0x90,       // 5: nop
416           0x90,       // 6: nop
417           0x90,       // 7: nop
418           0x0f, 0x0b, // 8: ud2
419       },
420       0xDEADBEEF);
421   uint64_t PrevSearchLengthForUndef = SearchLengthForUndef;
422   SearchLengthForUndef = 2;
423 
424   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 2);
425   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
426   EXPECT_THAT(
427       Result.ConditionalBranchNodes,
428       Each(AllOf(
429           Field(&ConditionalBranchNode::CFIProtection, Eq(false)),
430           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
431           Field(&ConditionalBranchNode::Target,
432                 HasPath(Result, ElementsAre(0xDEADBEEF + 4, 0xDEADBEEF + 5))),
433           Field(&ConditionalBranchNode::Fallthrough,
434                 HasPath(Result, ElementsAre(0xDEADBEEF + 2))))))
435       << PrintToString(Result);
436 
437   SearchLengthForUndef = PrevSearchLengthForUndef;
438 }
439 
440 // This test ensures when avoiding doing repeated work we still generate the
441 // paths correctly. We don't need to recalculate the flow from 0x2 -> 0x3 as it
442 // should only need to be generated once.
443 TEST_F(BasicGraphBuilderTest, BuildFlowGraphWithRepeatedWork) {
444   if (!SuccessfullyInitialised)
445     return;
446   Analysis.parseSectionContents(
447       {
448           0x75, 0x05, // 0: jne 7 [+5]
449           0x90,       // 2: nop
450           0xff, 0x10, // 3: callq *(%rax)
451           0x75, 0xfb, // 5: jne 2 [-5]
452           0x0f, 0x0b, // 7: ud2
453       },
454       0xDEADBEEF);
455   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0xDEADBEEF + 3);
456   EXPECT_THAT(Result.OrphanedNodes, IsEmpty());
457   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(2));
458   EXPECT_THAT(
459       Result.ConditionalBranchNodes,
460       Contains(AllOf(
461           Field(&ConditionalBranchNode::CFIProtection, Eq(true)),
462           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF)),
463           Field(&ConditionalBranchNode::Target,
464                 HasPath(Result, ElementsAre(0xDEADBEEF + 7))),
465           Field(&ConditionalBranchNode::Fallthrough,
466                 HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF + 3))))))
467       << PrintToString(Result);
468   EXPECT_THAT(
469       Result.ConditionalBranchNodes,
470       Contains(AllOf(
471           Field(&ConditionalBranchNode::CFIProtection, Eq(true)),
472           Field(&ConditionalBranchNode::Address, Eq(0xDEADBEEF + 5)),
473           Field(&ConditionalBranchNode::Target,
474                 HasPath(Result, ElementsAre(0xDEADBEEF + 2, 0xDEADBEEF + 3))),
475           Field(&ConditionalBranchNode::Fallthrough,
476                 HasPath(Result, ElementsAre(0xDEADBEEF + 7))))))
477       << PrintToString(Result);
478   EXPECT_THAT(Result.IntermediateNodes, SizeIs(1));
479   EXPECT_THAT(Result.IntermediateNodes,
480               UnorderedElementsAre(Pair(0xDEADBEEF + 2, 0xDEADBEEF + 3)));
481 }
482 
483 TEST_F(BasicGraphBuilderTest, BuildFlowGraphComplexExample) {
484   if (!SuccessfullyInitialised)
485     return;
486   // The following code has this graph:
487   //  +----------+      +--------------+
488   //  |    20    | <--- |      0       |
489   //  +----------+      +--------------+
490   //    |                 |
491   //    v                 v
492   //  +----------+      +--------------+
493   //  |    21    |      |      2       |
494   //  +----------+      +--------------+
495   //    |                 |
496   //    v                 v
497   //  +----------+      +--------------+
498   //  | 22 (ud2) |  +-> |      7       |
499   //  +----------+  |   +--------------+
500   //    ^           |     |
501   //    |           |     v
502   //  +----------+  |   +--------------+
503   //  |    4     |  |   |      8       |
504   //  +----------+  |   +--------------+
505   //    |           |     |
506   //    v           |     v
507   //  +----------+  |   +--------------+    +------------+
508   //  |    6     | -+   | 9 (indirect) | <- |     13     |
509   //  +----------+      +--------------+    +------------+
510   //                      ^                   |
511   //                      |                   v
512   //                    +--------------+    +------------+
513   //                    |      11      |    | 15 (error) |
514   //                    +--------------+    +------------+
515   // Or, in image format: https://i.imgur.com/aX5fCoi.png
516 
517   Analysis.parseSectionContents(
518       {
519           0x75, 0x12,                   // 0: jne 20 [+18]
520           0xeb, 0x03,                   // 2: jmp 7 [+3]
521           0x75, 0x10,                   // 4: jne 22 [+16]
522           0x90,                         // 6: nop
523           0x90,                         // 7: nop
524           0x90,                         // 8: nop
525           0xff, 0x10,                   // 9: callq *(%rax)
526           0xeb, 0xfc,                   // 11: jmp 9 [-4]
527           0x75, 0xfa,                   // 13: jne 9 [-6]
528           0xe8, 0x78, 0x56, 0x34, 0x12, // 15: callq OUTOFBOUNDS [+0x12345678]
529           0x90,                         // 20: nop
530           0x90,                         // 21: nop
531           0x0f, 0x0b,                   // 22: ud2
532       },
533       0x1000);
534   uint64_t PrevSearchLengthForUndef = SearchLengthForUndef;
535   SearchLengthForUndef = 5;
536 
537   GraphResult Result = GraphBuilder::buildFlowGraph(Analysis, 0x1000 + 9);
538 
539   EXPECT_THAT(Result.OrphanedNodes, SizeIs(1));
540   EXPECT_THAT(Result.ConditionalBranchNodes, SizeIs(3));
541 
542   EXPECT_THAT(
543       Result.OrphanedNodes,
544       Each(AllOf(Eq(0x1000u + 11),
545                  HasPath(Result, ElementsAre(0x1000 + 11, 0x1000 + 9)))))
546       << PrintToString(Result);
547 
548   EXPECT_THAT(Result.ConditionalBranchNodes,
549               Contains(AllOf(
550                   Field(&ConditionalBranchNode::CFIProtection, Eq(true)),
551                   Field(&ConditionalBranchNode::Address, Eq(0x1000u)),
552                   Field(&ConditionalBranchNode::Target,
553                         HasPath(Result, ElementsAre(0x1000 + 20, 0x1000 + 21,
554                                                     0x1000 + 22))),
555                   Field(&ConditionalBranchNode::Fallthrough,
556                         HasPath(Result, ElementsAre(0x1000 + 2, 0x1000 + 7,
557                                                     0x1000 + 8, 0x1000 + 9))))))
558       << PrintToString(Result);
559 
560   EXPECT_THAT(Result.ConditionalBranchNodes,
561               Contains(AllOf(
562                   Field(&ConditionalBranchNode::CFIProtection, Eq(true)),
563                   Field(&ConditionalBranchNode::Address, Eq(0x1000u + 4)),
564                   Field(&ConditionalBranchNode::Target,
565                         HasPath(Result, ElementsAre(0x1000 + 22))),
566                   Field(&ConditionalBranchNode::Fallthrough,
567                         HasPath(Result, ElementsAre(0x1000 + 6, 0x1000 + 7,
568                                                     0x1000 + 8, 0x1000 + 9))))))
569       << PrintToString(Result);
570 
571   EXPECT_THAT(
572       Result.ConditionalBranchNodes,
573       Contains(AllOf(Field(&ConditionalBranchNode::CFIProtection, Eq(false)),
574                      Field(&ConditionalBranchNode::Address, Eq(0x1000u + 13)),
575                      Field(&ConditionalBranchNode::Target,
576                            HasPath(Result, ElementsAre(0x1000 + 9))),
577                      Field(&ConditionalBranchNode::Fallthrough,
578                            HasPath(Result, ElementsAre(0x1000 + 15))))))
579       << PrintToString(Result);
580 
581   SearchLengthForUndef = PrevSearchLengthForUndef;
582 }
583 
584 } // anonymous namespace
585 } // end namespace cfi_verify
586 } // end namespace llvm
587