1 //===- llvm/unittest/IR/DebugInfo.cpp - DebugInfo tests -------------------===//
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/IR/DebugInfo.h"
10 #include "llvm/AsmParser/Parser.h"
11 #include "llvm/IR/DebugInfoMetadata.h"
12 #include "llvm/IR/IntrinsicInst.h"
13 #include "llvm/IR/LLVMContext.h"
14 #include "llvm/IR/Module.h"
15 #include "llvm/IR/Verifier.h"
16 #include "llvm/Support/SourceMgr.h"
17 #include "llvm/Transforms/Utils/Local.h"
18 #include "gtest/gtest.h"
19 
20 using namespace llvm;
21 
22 static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
23   SMDiagnostic Err;
24   std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C);
25   if (!Mod)
26     Err.print("DebugInfoTest", errs());
27   return Mod;
28 }
29 
30 namespace {
31 
32 TEST(DINodeTest, getFlag) {
33   // Some valid flags.
34   EXPECT_EQ(DINode::FlagPublic, DINode::getFlag("DIFlagPublic"));
35   EXPECT_EQ(DINode::FlagProtected, DINode::getFlag("DIFlagProtected"));
36   EXPECT_EQ(DINode::FlagPrivate, DINode::getFlag("DIFlagPrivate"));
37   EXPECT_EQ(DINode::FlagVector, DINode::getFlag("DIFlagVector"));
38   EXPECT_EQ(DINode::FlagRValueReference,
39             DINode::getFlag("DIFlagRValueReference"));
40 
41   // FlagAccessibility shouldn't work.
42   EXPECT_EQ(0u, DINode::getFlag("DIFlagAccessibility"));
43 
44   // Some other invalid strings.
45   EXPECT_EQ(0u, DINode::getFlag("FlagVector"));
46   EXPECT_EQ(0u, DINode::getFlag("Vector"));
47   EXPECT_EQ(0u, DINode::getFlag("other things"));
48   EXPECT_EQ(0u, DINode::getFlag("DIFlagOther"));
49 }
50 
51 TEST(DINodeTest, getFlagString) {
52   // Some valid flags.
53   EXPECT_EQ(StringRef("DIFlagPublic"),
54             DINode::getFlagString(DINode::FlagPublic));
55   EXPECT_EQ(StringRef("DIFlagProtected"),
56             DINode::getFlagString(DINode::FlagProtected));
57   EXPECT_EQ(StringRef("DIFlagPrivate"),
58             DINode::getFlagString(DINode::FlagPrivate));
59   EXPECT_EQ(StringRef("DIFlagVector"),
60             DINode::getFlagString(DINode::FlagVector));
61   EXPECT_EQ(StringRef("DIFlagRValueReference"),
62             DINode::getFlagString(DINode::FlagRValueReference));
63 
64   // FlagAccessibility actually equals FlagPublic.
65   EXPECT_EQ(StringRef("DIFlagPublic"),
66             DINode::getFlagString(DINode::FlagAccessibility));
67 
68   // Some other invalid flags.
69   EXPECT_EQ(StringRef(),
70             DINode::getFlagString(DINode::FlagPublic | DINode::FlagVector));
71   EXPECT_EQ(StringRef(), DINode::getFlagString(DINode::FlagFwdDecl |
72                                                DINode::FlagArtificial));
73   EXPECT_EQ(StringRef(),
74             DINode::getFlagString(static_cast<DINode::DIFlags>(0xffff)));
75 }
76 
77 TEST(DINodeTest, splitFlags) {
78 // Some valid flags.
79 #define CHECK_SPLIT(FLAGS, VECTOR, REMAINDER)                                  \
80   {                                                                            \
81     SmallVector<DINode::DIFlags, 8> V;                                         \
82     EXPECT_EQ(REMAINDER, DINode::splitFlags(FLAGS, V));                        \
83     EXPECT_TRUE(makeArrayRef(V).equals(VECTOR));                               \
84   }
85   CHECK_SPLIT(DINode::FlagPublic, {DINode::FlagPublic}, DINode::FlagZero);
86   CHECK_SPLIT(DINode::FlagProtected, {DINode::FlagProtected}, DINode::FlagZero);
87   CHECK_SPLIT(DINode::FlagPrivate, {DINode::FlagPrivate}, DINode::FlagZero);
88   CHECK_SPLIT(DINode::FlagVector, {DINode::FlagVector}, DINode::FlagZero);
89   CHECK_SPLIT(DINode::FlagRValueReference, {DINode::FlagRValueReference},
90               DINode::FlagZero);
91   DINode::DIFlags Flags[] = {DINode::FlagFwdDecl, DINode::FlagVector};
92   CHECK_SPLIT(DINode::FlagFwdDecl | DINode::FlagVector, Flags,
93               DINode::FlagZero);
94   CHECK_SPLIT(DINode::FlagZero, {}, DINode::FlagZero);
95 #undef CHECK_SPLIT
96 }
97 
98 TEST(StripTest, LoopMetadata) {
99   LLVMContext C;
100   std::unique_ptr<Module> M = parseIR(C, R"(
101     define void @f() !dbg !5 {
102       ret void, !dbg !10, !llvm.loop !11
103     }
104 
105     !llvm.dbg.cu = !{!0}
106     !llvm.debugify = !{!3, !3}
107     !llvm.module.flags = !{!4}
108 
109     !0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1, producer: "debugify", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
110     !1 = !DIFile(filename: "loop.ll", directory: "/")
111     !2 = !{}
112     !3 = !{i32 1}
113     !4 = !{i32 2, !"Debug Info Version", i32 3}
114     !5 = distinct !DISubprogram(name: "f", linkageName: "f", scope: null, file: !1, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !7)
115     !6 = !DISubroutineType(types: !2)
116     !7 = !{!8}
117     !8 = !DILocalVariable(name: "1", scope: !5, file: !1, line: 1, type: !9)
118     !9 = !DIBasicType(name: "ty32", size: 32, encoding: DW_ATE_unsigned)
119     !10 = !DILocation(line: 1, column: 1, scope: !5)
120     !11 = distinct !{!11, !10, !10}
121 )");
122 
123   // Look up the debug info emission kind for the CU via the loop metadata
124   // attached to the terminator. If, when stripping non-line table debug info,
125   // we update the terminator's metadata correctly, we should be able to
126   // observe the change in emission kind for the CU.
127   auto getEmissionKind = [&]() {
128     Instruction &I = *M->getFunction("f")->getEntryBlock().getFirstNonPHI();
129     MDNode *LoopMD = I.getMetadata(LLVMContext::MD_loop);
130     return cast<DILocation>(LoopMD->getOperand(1))
131         ->getScope()
132         ->getSubprogram()
133         ->getUnit()
134         ->getEmissionKind();
135   };
136 
137   EXPECT_EQ(getEmissionKind(), DICompileUnit::FullDebug);
138 
139   bool Changed = stripNonLineTableDebugInfo(*M);
140   EXPECT_TRUE(Changed);
141 
142   EXPECT_EQ(getEmissionKind(), DICompileUnit::LineTablesOnly);
143 
144   bool BrokenDebugInfo = false;
145   bool HardError = verifyModule(*M, &errs(), &BrokenDebugInfo);
146   EXPECT_FALSE(HardError);
147   EXPECT_FALSE(BrokenDebugInfo);
148 }
149 
150 TEST(MetadataTest, DeleteInstUsedByDbgValue) {
151   LLVMContext C;
152   std::unique_ptr<Module> M = parseIR(C, R"(
153     define i16 @f(i16 %a) !dbg !6 {
154       %b = add i16 %a, 1, !dbg !11
155       call void @llvm.dbg.value(metadata i16 %b, metadata !9, metadata !DIExpression()), !dbg !11
156       ret i16 0, !dbg !11
157     }
158     declare void @llvm.dbg.value(metadata, metadata, metadata) #0
159     attributes #0 = { nounwind readnone speculatable willreturn }
160 
161     !llvm.dbg.cu = !{!0}
162     !llvm.module.flags = !{!5}
163 
164     !0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1, producer: "debugify", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
165     !1 = !DIFile(filename: "t.ll", directory: "/")
166     !2 = !{}
167     !5 = !{i32 2, !"Debug Info Version", i32 3}
168     !6 = distinct !DISubprogram(name: "foo", linkageName: "foo", scope: null, file: !1, line: 1, type: !7, scopeLine: 1, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !8)
169     !7 = !DISubroutineType(types: !2)
170     !8 = !{!9}
171     !9 = !DILocalVariable(name: "1", scope: !6, file: !1, line: 1, type: !10)
172     !10 = !DIBasicType(name: "ty16", size: 16, encoding: DW_ATE_unsigned)
173     !11 = !DILocation(line: 1, column: 1, scope: !6)
174 )");
175 
176   // Find %b = add ...
177   Instruction &I = *M->getFunction("f")->getEntryBlock().getFirstNonPHI();
178 
179   // Find the dbg.value using %b.
180   SmallVector<DbgValueInst *, 1> DVIs;
181   findDbgValues(DVIs, &I);
182 
183   // Delete %b. The dbg.value should now point to undef.
184   I.eraseFromParent();
185   EXPECT_TRUE(isa<UndefValue>(DVIs[0]->getValue()));
186 }
187 
188 } // end namespace
189