1 files changed, 127 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/ModuleDebugInfoPrinter.cpp b/llvm/lib/Analysis/ModuleDebugInfoPrinter.cpp
new file mode 100644
index 000000000000..519242759824
--- /dev/null
+++ b/llvm/lib/Analysis/ModuleDebugInfoPrinter.cpp
@@ -0,0 +1,127 @@
+//===-- ModuleDebugInfoPrinter.cpp - Prints module debug info metadata ----===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass decodes the debug info metadata in a module and prints in a
+// (sufficiently-prepared-) human-readable form.
+//
+// For example, run this pass from opt along with the -analyze option, and
+// it'll print to standard output.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/Passes.h"
+#include "llvm/IR/DebugInfo.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+namespace {
+  class ModuleDebugInfoPrinter : public ModulePass {
+    DebugInfoFinder Finder;
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    ModuleDebugInfoPrinter() : ModulePass(ID) {
+      initializeModuleDebugInfoPrinterPass(*PassRegistry::getPassRegistry());
+    }
+
+    bool runOnModule(Module &M) override;
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+    }
+    void print(raw_ostream &O, const Module *M) const override;
+  };
+}
+
+char ModuleDebugInfoPrinter::ID = 0;
+INITIALIZE_PASS(ModuleDebugInfoPrinter, "module-debuginfo",
+                "Decodes module-level debug info", false, true)
+
+ModulePass *llvm::createModuleDebugInfoPrinterPass() {
+  return new ModuleDebugInfoPrinter();
+}
+
+bool ModuleDebugInfoPrinter::runOnModule(Module &M) {
+  Finder.processModule(M);
+  return false;
+}
+
+static void printFile(raw_ostream &O, StringRef Filename, StringRef Directory,
+                      unsigned Line = 0) {
+  if (Filename.empty())
+    return;
+
+  O << " from ";
+  if (!Directory.empty())
+    O << Directory << "/";
+  O << Filename;
+  if (Line)
+    O << ":" << Line;
+}
+
+void ModuleDebugInfoPrinter::print(raw_ostream &O, const Module *M) const {
+  // Printing the nodes directly isn't particularly helpful (since they
+  // reference other nodes that won't be printed, particularly for the
+  // filenames), so just print a few useful things.
+  for (DICompileUnit *CU : Finder.compile_units()) {
+    O << "Compile unit: ";
+    auto Lang = dwarf::LanguageString(CU->getSourceLanguage());
+    if (!Lang.empty())
+      O << Lang;
+    else
+      O << "unknown-language(" << CU->getSourceLanguage() << ")";
+    printFile(O, CU->getFilename(), CU->getDirectory());
+    O << '\n';
+  }
+
+  for (DISubprogram *S : Finder.subprograms()) {
+    O << "Subprogram: " << S->getName();
+    printFile(O, S->getFilename(), S->getDirectory(), S->getLine());
+    if (!S->getLinkageName().empty())
+      O << " ('" << S->getLinkageName() << "')";
+    O << '\n';
+  }
+
+  for (auto GVU : Finder.global_variables()) {
+    const auto *GV = GVU->getVariable();
+    O << "Global variable: " << GV->getName();
+    printFile(O, GV->getFilename(), GV->getDirectory(), GV->getLine());
+    if (!GV->getLinkageName().empty())
+      O << " ('" << GV->getLinkageName() << "')";
+    O << '\n';
+  }
+
+  for (const DIType *T : Finder.types()) {
+    O << "Type:";
+    if (!T->getName().empty())
+      O << ' ' << T->getName();
+    printFile(O, T->getFilename(), T->getDirectory(), T->getLine());
+    if (auto *BT = dyn_cast<DIBasicType>(T)) {
+      O << " ";
+      auto Encoding = dwarf::AttributeEncodingString(BT->getEncoding());
+      if (!Encoding.empty())
+        O << Encoding;
+      else
+        O << "unknown-encoding(" << BT->getEncoding() << ')';
+    } else {
+      O << ' ';
+      auto Tag = dwarf::TagString(T->getTag());
+      if (!Tag.empty())
+        O << Tag;
+      else
+        O << "unknown-tag(" << T->getTag() << ")";
+    }
+    if (auto *CT = dyn_cast<DICompositeType>(T)) {
+      if (auto *S = CT->getRawIdentifier())
+        O << " (identifier: '" << S->getString() << "')";
+    }
+    O << '\n';
+  }
+}