LLVM  3.7.0
ModuleDebugInfoPrinter.cpp
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1 //===-- ModuleDebugInfoPrinter.cpp - Prints module debug info metadata ----===//
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 // This pass decodes the debug info metadata in a module and prints in a
11 // (sufficiently-prepared-) human-readable form.
12 //
13 // For example, run this pass from opt along with the -analyze option, and
14 // it'll print to standard output.
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #include "llvm/Analysis/Passes.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/IR/DebugInfo.h"
21 #include "llvm/IR/Function.h"
22 #include "llvm/Pass.h"
25 using namespace llvm;
26 
27 namespace {
28  class ModuleDebugInfoPrinter : public ModulePass {
29  DebugInfoFinder Finder;
30  public:
31  static char ID; // Pass identification, replacement for typeid
32  ModuleDebugInfoPrinter() : ModulePass(ID) {
34  }
35 
36  bool runOnModule(Module &M) override;
37 
38  void getAnalysisUsage(AnalysisUsage &AU) const override {
39  AU.setPreservesAll();
40  }
41  void print(raw_ostream &O, const Module *M) const override;
42  };
43 }
44 
46 INITIALIZE_PASS(ModuleDebugInfoPrinter, "module-debuginfo",
47  "Decodes module-level debug info", false, true)
48 
50  return new ModuleDebugInfoPrinter();
51 }
52 
53 bool ModuleDebugInfoPrinter::runOnModule(Module &M) {
54  Finder.processModule(M);
55  return false;
56 }
57 
58 static void printFile(raw_ostream &O, StringRef Filename, StringRef Directory,
59  unsigned Line = 0) {
60  if (Filename.empty())
61  return;
62 
63  O << " from ";
64  if (!Directory.empty())
65  O << Directory << "/";
66  O << Filename;
67  if (Line)
68  O << ":" << Line;
69 }
70 
71 void ModuleDebugInfoPrinter::print(raw_ostream &O, const Module *M) const {
72  // Printing the nodes directly isn't particularly helpful (since they
73  // reference other nodes that won't be printed, particularly for the
74  // filenames), so just print a few useful things.
75  for (DICompileUnit *CU : Finder.compile_units()) {
76  O << "Compile unit: ";
77  if (const char *Lang = dwarf::LanguageString(CU->getSourceLanguage()))
78  O << Lang;
79  else
80  O << "unknown-language(" << CU->getSourceLanguage() << ")";
81  printFile(O, CU->getFilename(), CU->getDirectory());
82  O << '\n';
83  }
84 
85  for (DISubprogram *S : Finder.subprograms()) {
86  O << "Subprogram: " << S->getName();
87  printFile(O, S->getFilename(), S->getDirectory(), S->getLine());
88  if (!S->getLinkageName().empty())
89  O << " ('" << S->getLinkageName() << "')";
90  O << '\n';
91  }
92 
93  for (const DIGlobalVariable *GV : Finder.global_variables()) {
94  O << "Global variable: " << GV->getName();
95  printFile(O, GV->getFilename(), GV->getDirectory(), GV->getLine());
96  if (!GV->getLinkageName().empty())
97  O << " ('" << GV->getLinkageName() << "')";
98  O << '\n';
99  }
100 
101  for (const DIType *T : Finder.types()) {
102  O << "Type:";
103  if (!T->getName().empty())
104  O << ' ' << T->getName();
105  printFile(O, T->getFilename(), T->getDirectory(), T->getLine());
106  if (auto *BT = dyn_cast<DIBasicType>(T)) {
107  O << " ";
108  if (const char *Encoding =
109  dwarf::AttributeEncodingString(BT->getEncoding()))
110  O << Encoding;
111  else
112  O << "unknown-encoding(" << BT->getEncoding() << ')';
113  } else {
114  O << ' ';
115  if (const char *Tag = dwarf::TagString(T->getTag()))
116  O << Tag;
117  else
118  O << "unknown-tag(" << T->getTag() << ")";
119  }
120  if (auto *CT = dyn_cast<DICompositeType>(T)) {
121  if (auto *S = CT->getRawIdentifier())
122  O << " (identifier: '" << S->getString() << "')";
123  }
124  O << '\n';
125  }
126 }
const char * LanguageString(unsigned Language)
Definition: Dwarf.cpp:341
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:114
INITIALIZE_PASS(ModuleDebugInfoPrinter,"module-debuginfo","Decodes module-level debug info", false, true) ModulePass *llvm
const char * TagString(unsigned Tag)
Definition: Dwarf.cpp:21
Utility to find all debug info in a module.
Definition: DebugInfo.h:72
static void printFile(raw_ostream &O, StringRef Filename, StringRef Directory, unsigned Line=0)
void print(raw_ostream &O) const
Implement operator<< on Value.
Definition: AsmWriter.cpp:3209
Subprogram description.
void initializeModuleDebugInfoPrinterPass(PassRegistry &)
Represent the analysis usage information of a pass.
const char * AttributeEncodingString(unsigned Encoding)
Definition: Dwarf.cpp:264
Base class for types.
void setPreservesAll()
Set by analyses that do not transform their input at all.
ModulePass * createModuleDebugInfoPrinterPass()
ModulePass class - This class is used to implement unstructured interprocedural optimizations and ana...
Definition: Pass.h:236
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:38
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:40
bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:110