[dwarfdump] Add support for dumping accelerator tables.

The class used for the dump only allows to dump for the moment, but
it can (and will) be easily extended to support search also.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221836 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/DebugInfo/DIContext.h

@@ -107,7 +107,11 @@ enum DIDumpType {
   DIDT_GnuPubtypes,
   DIDT_Str,
   DIDT_StrDwo,
-  DIDT_StrOffsetsDwo
+  DIDT_StrOffsetsDwo,
+  DIDT_AppleNames,
+  DIDT_AppleTypes,
+  DIDT_AppleNamespaces,
+  DIDT_AppleObjC
 };
 
 // In place of applying the relocations to the data we've read from disk we use

lib/DebugInfo/CMakeLists.txt

@@ -1,6 +1,7 @@
 add_llvm_library(LLVMDebugInfo
   DIContext.cpp
   DWARFAbbreviationDeclaration.cpp
+  DWARFAcceleratorTable.cpp
   DWARFCompileUnit.cpp
   DWARFContext.cpp
   DWARFDebugAbbrev.cpp

lib/DebugInfo/DWARFAcceleratorTable.cpp

@@ -0,0 +1,110 @@
+#include "DWARFAcceleratorTable.h"
+
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace llvm {
+
+bool DWARFAcceleratorTable::extract() {
+  uint32_t Offset = 0;
+
+  // Check that we can at least read the header.
+  if (!AccelSection.isValidOffset(offsetof(Header, HeaderDataLength)+4))
+    return false;
+
+  Hdr.Magic = AccelSection.getU32(&Offset);
+  Hdr.Version = AccelSection.getU16(&Offset);
+  Hdr.HashFunction = AccelSection.getU16(&Offset);
+  Hdr.NumBuckets = AccelSection.getU32(&Offset);
+  Hdr.NumHashes = AccelSection.getU32(&Offset);
+  Hdr.HeaderDataLength = AccelSection.getU32(&Offset);
+
+  // Check that we can read all the hashes and offsets from the
+  // section (see SourceLevelDebugging.rst for the structure of the index).
+  if (!AccelSection.isValidOffset(sizeof(Hdr) + Hdr.HeaderDataLength +
+                                  Hdr.NumBuckets*4 + Hdr.NumHashes*8))
+    return false;
+
+  HdrData.DIEOffsetBase = AccelSection.getU32(&Offset);
+  uint32_t NumAtoms = AccelSection.getU32(&Offset);
+
+  for (unsigned i = 0; i < NumAtoms; ++i) {
+    auto Atom = std::make_pair(AccelSection.getU16(&Offset),
+                               DWARFFormValue(AccelSection.getU16(&Offset)));
+    HdrData.Atoms.push_back(Atom);
+  }
+
+  return true;
+}
+
+void DWARFAcceleratorTable::dump(raw_ostream &OS) {
+  // Dump the header.
+  OS << "Magic = " << format("0x%08x", Hdr.Magic) << '\n';
+  OS << "Version = " << format("0x%04x", Hdr.Version) << '\n';
+  OS << "Hash function = " << format("0x%08x", Hdr.HashFunction) << '\n';
+  OS << "Bucket count = " << Hdr.NumBuckets << '\n';
+  OS << "Hashes count = " << Hdr.NumHashes << '\n';
+  OS << "HeaderData length = " << Hdr.HeaderDataLength << '\n';
+  OS << "DIE offset base = " << HdrData.DIEOffsetBase << '\n';
+  OS << "Number of atoms = " << HdrData.Atoms.size() << '\n';
+
+  unsigned i = 0;
+  for (const auto &Atom: HdrData.Atoms) {
+    OS << format("Atom[%d] ", i++);
+    OS << " Type: " << dwarf::AtomTypeString(Atom.first);
+    OS << " Form: " << dwarf::FormEncodingString(Atom.second.getForm());
+    OS << "\n";
+  }
+
+  // Now go through the actual tables and dump them.
+  uint32_t Offset = sizeof(Hdr) + Hdr.HeaderDataLength;
+  unsigned HashesBase = Offset + Hdr.NumBuckets * 4;
+  unsigned OffsetsBase = HashesBase + Hdr.NumHashes * 4;
+
+  for (unsigned Bucket = 0; Bucket < Hdr.NumBuckets; ++Bucket) {
+    unsigned Index;
+    Index = AccelSection.getU32(&Offset);
+
+    OS << format("Bucket[%d]\n", Bucket);
+    if (Index == UINT32_MAX) {
+      OS << "  EMPTY\n";
+      continue;
+    }
+
+    for (unsigned HashIdx = Index; HashIdx < Hdr.NumHashes; ++HashIdx) {
+      unsigned HashOffset = HashesBase + HashIdx*4;
+      unsigned OffsetsOffset = OffsetsBase + HashIdx*4;
+      uint32_t Hash = AccelSection.getU32(&HashOffset);
+
+      if (Hash % Hdr.NumBuckets != Bucket)
+        break;
+
+      unsigned DataOffset = AccelSection.getU32(&OffsetsOffset);
+      OS << format("  Hash = 0x%08x Offset = 0x%08x\n", Hash, DataOffset);
+      if (!AccelSection.isValidOffset(DataOffset)) {
+        OS << "    Invalid section offset\n";
+        continue;
+      }
+      while (unsigned StringOffset = AccelSection.getU32(&DataOffset)) {
+        OS << format("    Name: %08x \"%s\"\n", StringOffset,
+                     StringSection.getCStr(&StringOffset));
+        unsigned NumData = AccelSection.getU32(&DataOffset);
+        for (unsigned Data = 0; Data < NumData; ++Data) {
+          OS << format("    Data[%d] => ", Data);
+          unsigned i = 0;
+          for (auto &Atom : HdrData.Atoms) {
+            OS << format("{Atom[%d]: ", i++);
+            if (Atom.second.extractValue(AccelSection, &DataOffset, nullptr))
+              Atom.second.dump(OS, nullptr);
+            else
+              OS << "Error extracting the value";
+            OS << "} ";
+          }
+          OS << '\n';
+        }
+      }
+    }
+  }
+}
+}

lib/DebugInfo/DWARFAcceleratorTable.h

@@ -0,0 +1,38 @@
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/DebugInfo/DWARFFormValue.h"
+
+#include <cstdint>
+
+namespace llvm {
+
+class DWARFAcceleratorTable {
+
+  struct Header {
+    uint32_t Magic;
+    uint16_t Version;
+    uint16_t HashFunction;
+    uint32_t NumBuckets;
+    uint32_t NumHashes;
+    uint32_t HeaderDataLength;
+  };
+
+  struct HeaderData {
+    typedef uint16_t AtomType;
+    uint32_t DIEOffsetBase;
+    SmallVector<std::pair<AtomType, DWARFFormValue>, 1> Atoms;
+  };
+
+  struct Header Hdr;
+  struct HeaderData HdrData;
+  DataExtractor AccelSection;
+  DataExtractor StringSection;
+public:
+  DWARFAcceleratorTable(DataExtractor AccelSection, DataExtractor StringSection)
+    : AccelSection(AccelSection), StringSection(StringSection) {}
+
+  bool extract();
+  void dump(raw_ostream &OS);
+};
+
+}

lib/DebugInfo/DWARFContext.cpp

@@ -9,6 +9,7 @@
 
 #include "DWARFContext.h"
 #include "DWARFDebugArangeSet.h"
+#include "DWARFAcceleratorTable.h"
 
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringSwitch.h"
@@ -59,6 +60,17 @@ static void dumpPubSection(raw_ostream &OS, StringRef Name, StringRef Data,
   }
 }
 
+static void dumpAccelSection(raw_ostream &OS, StringRef Name, StringRef Data,
+                             StringRef StringSection, bool LittleEndian) {
+  DataExtractor AccelSection(Data, LittleEndian, 0);
+  DataExtractor StrData(StringSection, LittleEndian, 0);
+  OS << "\n." << Name << " contents:\n";
+  DWARFAcceleratorTable Accel(AccelSection, StrData);
+  if (!Accel.extract())
+    return;
+  Accel.dump(OS);
+}
+
 void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) {
   if (DumpType == DIDT_All || DumpType == DIDT_Abbrev) {
     OS << ".debug_abbrev contents:\n";
@@ -218,6 +230,22 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) {
       OS << format("%8.8x\n", strOffsetExt.getU32(&offset));
     }
   }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_AppleNames)
+    dumpAccelSection(OS, "apple_names", getAppleNamesSection(),
+                     getStringSection(), isLittleEndian());
+
+  if (DumpType == DIDT_All || DumpType == DIDT_AppleTypes)
+    dumpAccelSection(OS, "apple_types", getAppleTypesSection(),
+                     getStringSection(), isLittleEndian());
+
+  if (DumpType == DIDT_All || DumpType == DIDT_AppleNamespaces)
+    dumpAccelSection(OS, "apple_namespaces", getAppleNamespacesSection(),
+                     getStringSection(), isLittleEndian());
+
+  if (DumpType == DIDT_All || DumpType == DIDT_AppleObjC)
+    dumpAccelSection(OS, "apple_objc", getAppleObjCSection(),
+                     getStringSection(), isLittleEndian());
 }
 
 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
@@ -565,6 +593,11 @@ DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj)
             .Case("debug_str.dwo", &StringDWOSection)
             .Case("debug_str_offsets.dwo", &StringOffsetDWOSection)
             .Case("debug_addr", &AddrSection)
+            .Case("apple_names", &AppleNamesSection)
+            .Case("apple_types", &AppleTypesSection)
+            .Case("apple_namespaces", &AppleNamespacesSection)
+            .Case("apple_namespac", &AppleNamespacesSection)
+            .Case("apple_objc", &AppleObjCSection)
             // Any more debug info sections go here.
             .Default(nullptr);
     if (SectionData) {

lib/DebugInfo/DWARFContext.h

@@ -192,6 +192,10 @@ class DWARFContext : public DIContext {
   virtual StringRef getStringOffsetDWOSection() = 0;
   virtual StringRef getRangeDWOSection() = 0;
   virtual StringRef getAddrSection() = 0;
+  virtual StringRef getAppleNamesSection() = 0;
+  virtual StringRef getAppleTypesSection() = 0;
+  virtual StringRef getAppleNamespacesSection() = 0;
+  virtual StringRef getAppleObjCSection() = 0;
 
   static bool isSupportedVersion(unsigned version) {
     return version == 2 || version == 3 || version == 4;
@@ -236,6 +240,10 @@ class DWARFContextInMemory : public DWARFContext {
   StringRef StringOffsetDWOSection;
   StringRef RangeDWOSection;
   StringRef AddrSection;
+  StringRef AppleNamesSection;
+  StringRef AppleTypesSection;
+  StringRef AppleNamespacesSection;
+  StringRef AppleObjCSection;
 
   SmallVector<SmallString<32>, 4> UncompressedSections;
 
@@ -256,6 +264,10 @@ class DWARFContextInMemory : public DWARFContext {
   StringRef getPubTypesSection() override { return PubTypesSection; }
   StringRef getGnuPubNamesSection() override { return GnuPubNamesSection; }
   StringRef getGnuPubTypesSection() override { return GnuPubTypesSection; }
+  StringRef getAppleNamesSection() override { return AppleNamesSection; }
+  StringRef getAppleTypesSection() override { return AppleTypesSection; }
+  StringRef getAppleNamespacesSection() override { return AppleNamespacesSection; }
+  StringRef getAppleObjCSection() override { return AppleObjCSection; }
 
   // Sections for DWARF5 split dwarf proposal.
   const DWARFSection &getInfoDWOSection() override { return InfoDWOSection; }

test/DebugInfo/Inputs/gmlt.ll

@@ -95,6 +95,8 @@
 ; CHECK: .debug_pubtypes contents:
 ; CHECK-NOT: Offset
 
+; CHECK: .apple{{.*}} contents:
+
 ; Function Attrs: nounwind uwtable
 define void @_Z2f1v() #0 {
 entry: