[DWARF5] Added support for debug_macro section parsing and dumping in llvm-dwarfdump.

Summary:
This patch adds parsing and dumping DWARFv5 .debug_macro section in llvm-dwarfdump,
it does not introduce any new switch. Existing switch "--debug-macro"
should be used to dump macinfo or macro section.

Reviewed By: dblaikie, ikudrin, jhenderson

Differential Revision: https://reviews.llvm.org/D73086

Author: SouraVX

llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h

@@ -61,6 +61,7 @@ class DWARFContext : public DIContext {
   std::unique_ptr<DWARFDebugLine> Line;
   std::unique_ptr<DWARFDebugFrame> DebugFrame;
   std::unique_ptr<DWARFDebugFrame> EHFrame;
+  std::unique_ptr<DWARFDebugMacro> Macro;
   std::unique_ptr<DWARFDebugMacro> Macinfo;
   std::unique_ptr<DWARFDebugNames> Names;
   std::unique_ptr<AppleAcceleratorTable> AppleNames;
@@ -104,6 +105,15 @@ class DWARFContext : public DIContext {
 
   std::unique_ptr<const DWARFObject> DObj;
 
+  /// Helper enum to distinguish between macro[.dwo] and macinfo[.dwo]
+  /// section.
+  enum MacroSecType {
+    MacinfoSection,
+    MacinfoDwoSection,
+    MacroSection
+    // FIXME: Add support for.debug_macro.dwo section.
+  };
+
 public:
   DWARFContext(std::unique_ptr<const DWARFObject> DObj,
                std::string DWPName = "",
@@ -272,12 +282,15 @@ class DWARFContext : public DIContext {
   /// Get a pointer to the parsed eh frame information object.
   const DWARFDebugFrame *getEHFrame();
 
-  /// Get a pointer to the parsed DebugMacro object.
+  /// Get a pointer to the parsed DebugMacinfo information object.
   const DWARFDebugMacro *getDebugMacinfo();
 
-  /// Get a pointer to the parsed dwo DebugMacro object.
+  /// Get a pointer to the parsed DebugMacinfoDWO information object.
   const DWARFDebugMacro *getDebugMacinfoDWO();
 
+  /// Get a pointer to the parsed DebugMacro information object.
+  const DWARFDebugMacro *getDebugMacro();
+
   /// Get a reference to the parsed accelerator table object.
   const DWARFDebugNames &getDebugNames();
 
@@ -382,6 +395,10 @@ class DWARFContext : public DIContext {
   }
 
 private:
+  /// Parse a macro[.dwo] or macinfo[.dwo] section.
+  std::unique_ptr<DWARFDebugMacro>
+  parseMacroOrMacinfo(MacroSecType SectionType);
+
   /// Return the compile unit which contains instruction with provided
   /// address.
   /// TODO: change input parameter from "uint64_t Address"

llvm/include/llvm/DebugInfo/DWARF/DWARFDebugMacro.h

@@ -10,14 +10,56 @@
 #define LLVM_DEBUGINFO_DWARF_DWARFDEBUGMACRO_H
 
 #include "llvm/ADT/SmallVector.h"
-#include "llvm/Support/DataExtractor.h"
+#include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/WithColor.h"
 #include <cstdint>
 
 namespace llvm {
 
 class raw_ostream;
 
 class DWARFDebugMacro {
+  /// DWARFv5 section 6.3.1 Macro Information Header.
+  enum HeaderFlagMask {
+#define HANDLE_MACRO_FLAG(ID, NAME) MACRO_##NAME = ID,
+#include "llvm/BinaryFormat/Dwarf.def"
+  };
+  struct MacroHeader {
+    /// Macro version information number.
+    uint16_t Version = 0;
+
+    /// The bits of the flags field are interpreted as a set of flags, some of
+    /// which may indicate that additional fields follow. The following flags,
+    /// beginning with the least significant bit, are defined:
+    /// offset_size_flag:
+    ///   If the offset_size_flag is zero, the header is for a 32-bit DWARF
+    ///   format macro section and all offsets are 4 bytes long; if it is one,
+    ///   the header is for a 64-bit DWARF format macro section and all offsets
+    ///   are 8 bytes long.
+    /// debug_line_offset_flag:
+    ///   If the debug_line_offset_flag is one, the debug_line_offset field (see
+    ///   below) is present. If zero, that field is omitted.
+    /// opcode_operands_table_flag:
+    ///   If the opcode_operands_table_flag is one, the opcode_operands_table
+    ///   field (see below) is present. If zero, that field is omitted.
+    uint8_t Flags;
+
+    /// debug_line_offset
+    ///   An offset in the .debug_line section of the beginning of the line
+    ///   number information in the containing compilation unit, encoded as a
+    ///   4-byte offset for a 32-bit DWARF format macro section and an 8-byte
+    ///   offset for a 64-bit DWARF format macro section.
+    uint64_t DebugLineOffset;
+
+    /// Print the macro header from the debug_macro section.
+    void dumpMacroHeader(raw_ostream &OS) const;
+
+    /// Parse the debug_macro header.
+    Error parseMacroHeader(DWARFDataExtractor Data, uint64_t *Offset);
+  };
+
   /// A single macro entry within a macro list.
   struct Entry {
     /// The type of the macro entry.
@@ -40,6 +82,10 @@ class DWARFDebugMacro {
   };
 
   struct MacroList {
+    // A value 0 in the `Header.Version` field indicates that we're parsing
+    // a macinfo[.dwo] section which doesn't have header itself, hence
+    // for that case other fields in the `Header` are uninitialized.
+    MacroHeader Header;
     SmallVector<Entry, 4> Macros;
     uint64_t Offset;
   };
@@ -50,11 +96,13 @@ class DWARFDebugMacro {
 public:
   DWARFDebugMacro() = default;
 
-  /// Print the macro list found within the debug_macinfo section.
+  /// Print the macro list found within the debug_macinfo/debug_macro section.
   void dump(raw_ostream &OS) const;
 
-  /// Parse the debug_macinfo section accessible via the 'data' parameter.
-  void parse(DataExtractor data);
+  /// Parse the debug_macinfo/debug_macro section accessible via the 'Data'
+  /// parameter.
+  Error parse(DataExtractor StringExtractor, DWARFDataExtractor Data,
+              bool IsMacro);
 
   /// Return whether the section has any entries.
   bool empty() const { return MacroLists.empty(); }

llvm/include/llvm/DebugInfo/DWARF/DWARFObject.h

@@ -47,6 +47,7 @@ class DWARFObject {
   virtual StringRef getStrSection() const { return ""; }
   virtual const DWARFSection &getRangesSection() const { return Dummy; }
   virtual const DWARFSection &getRnglistsSection() const { return Dummy; }
+  virtual const DWARFSection &getMacroSection() const { return Dummy; }
   virtual StringRef getMacinfoSection() const { return ""; }
   virtual StringRef getMacinfoDWOSection() const { return ""; }
   virtual const DWARFSection &getPubnamesSection() const { return Dummy; }

llvm/lib/DebugInfo/DWARF/DWARFContext.cpp

@@ -292,6 +292,36 @@ static void dumpRnglistsSection(
   }
 }
 
+std::unique_ptr<DWARFDebugMacro>
+DWARFContext::parseMacroOrMacinfo(MacroSecType SectionType) {
+  auto Macro = std::make_unique<DWARFDebugMacro>();
+  auto ParseAndDump = [&](DWARFDataExtractor &Data, bool IsMacro) {
+    if (Error Err = Macro->parse(getStringExtractor(), Data, IsMacro)) {
+      RecoverableErrorHandler(std::move(Err));
+      Macro = nullptr;
+    }
+  };
+  switch (SectionType) {
+  case MacinfoSection: {
+    DWARFDataExtractor Data(DObj->getMacinfoSection(), isLittleEndian(), 0);
+    ParseAndDump(Data, /*IsMacro=*/false);
+    break;
+  }
+  case MacinfoDwoSection: {
+    DWARFDataExtractor Data(DObj->getMacinfoDWOSection(), isLittleEndian(), 0);
+    ParseAndDump(Data, /*IsMacro=*/false);
+    break;
+  }
+  case MacroSection: {
+    DWARFDataExtractor Data(*DObj, DObj->getMacroSection(), isLittleEndian(),
+                            0);
+    ParseAndDump(Data, /*IsMacro=*/true);
+    break;
+  }
+  }
+  return std::move(Macro);
+}
+
 static void dumpLoclistsSection(raw_ostream &OS, DIDumpOptions DumpOpts,
                                 DWARFDataExtractor Data,
                                 const MCRegisterInfo *MRI,
@@ -444,14 +474,22 @@ void DWARFContext::dump(
                                    DObj->getEHFrameSection().Data))
     getEHFrame()->dump(OS, getRegisterInfo(), *Off);
 
+  if (shouldDump(Explicit, ".debug_macro", DIDT_ID_DebugMacro,
+                 DObj->getMacroSection().Data)) {
+    if (auto Macro = getDebugMacro())
+      Macro->dump(OS);
+  }
+
   if (shouldDump(Explicit, ".debug_macinfo", DIDT_ID_DebugMacro,
                  DObj->getMacinfoSection())) {
-    getDebugMacinfo()->dump(OS);
+    if (auto Macinfo = getDebugMacinfo())
+      Macinfo->dump(OS);
   }
 
   if (shouldDump(Explicit, ".debug_macinfo.dwo", DIDT_ID_DebugMacro,
                  DObj->getMacinfoDWOSection())) {
-    getDebugMacinfoDWO()->dump(OS);
+    if (auto MacinfoDWO = getDebugMacinfoDWO())
+      MacinfoDWO->dump(OS);
   }
 
   if (shouldDump(Explicit, ".debug_aranges", DIDT_ID_DebugAranges,
@@ -815,27 +853,24 @@ const DWARFDebugFrame *DWARFContext::getEHFrame() {
   return DebugFrame.get();
 }
 
-const DWARFDebugMacro *DWARFContext::getDebugMacinfoDWO() {
-  if (MacinfoDWO)
-    return MacinfoDWO.get();
-
-  DataExtractor MacinfoDWOData(DObj->getMacinfoDWOSection(), isLittleEndian(),
-                               0);
-  MacinfoDWO.reset(new DWARFDebugMacro());
-  MacinfoDWO->parse(MacinfoDWOData);
-  return MacinfoDWO.get();
+const DWARFDebugMacro *DWARFContext::getDebugMacro() {
+  if (!Macro)
+    Macro = parseMacroOrMacinfo(MacroSection);
+  return Macro.get();
 }
 
 const DWARFDebugMacro *DWARFContext::getDebugMacinfo() {
-  if (Macinfo)
-    return Macinfo.get();
-
-  DataExtractor MacinfoData(DObj->getMacinfoSection(), isLittleEndian(), 0);
-  Macinfo.reset(new DWARFDebugMacro());
-  Macinfo->parse(MacinfoData);
+  if (!Macinfo)
+    Macinfo = parseMacroOrMacinfo(MacinfoSection);
   return Macinfo.get();
 }
 
+const DWARFDebugMacro *DWARFContext::getDebugMacinfoDWO() {
+  if (!MacinfoDWO)
+    MacinfoDWO = parseMacroOrMacinfo(MacinfoDwoSection);
+  return MacinfoDWO.get();
+}
+
 template <typename T>
 static T &getAccelTable(std::unique_ptr<T> &Cache, const DWARFObject &Obj,
                         const DWARFSection &Section, StringRef StringSection,
@@ -1476,6 +1511,7 @@ class DWARFObjInMemory final : public DWARFObject {
   DWARFSectionMap PubtypesSection;
   DWARFSectionMap GnuPubnamesSection;
   DWARFSectionMap GnuPubtypesSection;
+  DWARFSectionMap MacroSection;
 
   DWARFSectionMap *mapNameToDWARFSection(StringRef Name) {
     return StringSwitch<DWARFSectionMap *>(Name)
@@ -1503,6 +1539,7 @@ class DWARFObjInMemory final : public DWARFObject {
         .Case("apple_namespaces", &AppleNamespacesSection)
         .Case("apple_namespac", &AppleNamespacesSection)
         .Case("apple_objc", &AppleObjCSection)
+        .Case("debug_macro", &MacroSection)
         .Default(nullptr);
   }
 
@@ -1847,6 +1884,7 @@ class DWARFObjInMemory final : public DWARFObject {
   const DWARFSection &getRnglistsSection() const override {
     return RnglistsSection;
   }
+  const DWARFSection &getMacroSection() const override { return MacroSection; }
   StringRef getMacinfoSection() const override { return MacinfoSection; }
   StringRef getMacinfoDWOSection() const override { return MacinfoDWOSection; }
   const DWARFSection &getPubnamesSection() const override { return PubnamesSection; }