[Dsymutil][Debuginfo][NFC] #3 Refactor dsymutil to separate DWARF optimizing part.

Summary:
This is the next portion of patches for dsymutil.

Create DwarfEmitter interface to generate all debug info tables.
Put DwarfEmitter into DwarfLinker library and make tools/dsymutil/DwarfStreamer
to be child of DwarfEmitter.

It passes check-all testing. MD5 checksum for clang .dSYM bundle matches
for the dsymutil with/without that patch.

Reviewers: JDevlieghere, friss, dblaikie, aprantl

Reviewed By: JDevlieghere

Subscribers: merge_guards_bot, hiraditya, thegameg, probinson, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D72476

1 files changed, 112 insertions, 0 deletions

diff --git a/llvm/include/llvm/DWARFLinker/DWARFLinker.h b/llvm/include/llvm/DWARFLinker/DWARFLinker.h
index 218c9641bfb..80df01ca053 100644
--- a/llvm/include/llvm/DWARFLinker/DWARFLinker.h
+++ b/llvm/include/llvm/DWARFLinker/DWARFLinker.h
@@ -9,10 +9,12 @@
 #ifndef LLVM_DWARFLINKER_DWARFLINKER_H
 #define LLVM_DWARFLINKER_DWARFLINKER_H
 
+#include "llvm/CodeGen/AccelTable.h"
 #include "llvm/CodeGen/NonRelocatableStringpool.h"
 #include "llvm/DWARFLinker/DWARFLinkerDeclContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/MC/MCDwarf.h"
 #include <map>
 
 namespace llvm {
@@ -81,6 +83,116 @@ public:
   virtual void clear() = 0;
 };
 
+/// DwarfEmitter presents interface to generate all debug info tables.
+class DwarfEmitter {
+public:
+  virtual ~DwarfEmitter();
+
+  /// Emit DIE containing warnings.
+  virtual void emitPaperTrailWarningsDie(const Triple &Triple, DIE &Die) = 0;
+
+  /// Emit section named SecName with content equals to
+  /// corresponding section in Obj.
+  virtual void emitSectionContents(const object::ObjectFile &Obj,
+                                   StringRef SecName) = 0;
+
+  /// Emit the abbreviation table \p Abbrevs to the debug_abbrev section.
+  virtual void
+  emitAbbrevs(const std::vector<std::unique_ptr<DIEAbbrev>> &Abbrevs,
+              unsigned DwarfVersion) = 0;
+
+  /// Emit the string table described by \p Pool.
+  virtual void emitStrings(const NonRelocatableStringpool &Pool) = 0;
+
+  /// Emit DWARF debug names.
+  virtual void
+  emitDebugNames(AccelTable<DWARF5AccelTableStaticData> &Table) = 0;
+
+  /// Emit Apple namespaces accelerator table.
+  virtual void
+  emitAppleNamespaces(AccelTable<AppleAccelTableStaticOffsetData> &Table) = 0;
+
+  /// Emit Apple names accelerator table.
+  virtual void
+  emitAppleNames(AccelTable<AppleAccelTableStaticOffsetData> &Table) = 0;
+
+  /// Emit Apple Objective-C accelerator table.
+  virtual void
+  emitAppleObjc(AccelTable<AppleAccelTableStaticOffsetData> &Table) = 0;
+
+  /// Emit Apple type accelerator table.
+  virtual void
+  emitAppleTypes(AccelTable<AppleAccelTableStaticTypeData> &Table) = 0;
+
+  /// Emit debug_ranges for \p FuncRange by translating the
+  /// original \p Entries.
+  virtual void emitRangesEntries(
+      int64_t UnitPcOffset, uint64_t OrigLowPc,
+      const FunctionIntervals::const_iterator &FuncRange,
+      const std::vector<DWARFDebugRangeList::RangeListEntry> &Entries,
+      unsigned AddressSize) = 0;
+
+  /// Emit debug_aranges entries for \p Unit and if \p DoRangesSection is true,
+  /// also emit the debug_ranges entries for the DW_TAG_compile_unit's
+  /// DW_AT_ranges attribute.
+  virtual void emitUnitRangesEntries(CompileUnit &Unit,
+                                     bool DoRangesSection) = 0;
+
+  /// Copy the debug_line over to the updated binary while unobfuscating the
+  /// file names and directories.
+  virtual void translateLineTable(DataExtractor LineData, uint64_t Offset) = 0;
+
+  /// Emit the line table described in \p Rows into the debug_line section.
+  virtual void emitLineTableForUnit(MCDwarfLineTableParams Params,
+                                    StringRef PrologueBytes,
+                                    unsigned MinInstLength,
+                                    std::vector<DWARFDebugLine::Row> &Rows,
+                                    unsigned AdddressSize) = 0;
+
+  /// Emit the .debug_pubnames contribution for \p Unit.
+  virtual void emitPubNamesForUnit(const CompileUnit &Unit) = 0;
+
+  /// Emit the .debug_pubtypes contribution for \p Unit.
+  virtual void emitPubTypesForUnit(const CompileUnit &Unit) = 0;
+
+  /// Emit a CIE.
+  virtual void emitCIE(StringRef CIEBytes) = 0;
+
+  /// Emit an FDE with data \p Bytes.
+  virtual void emitFDE(uint32_t CIEOffset, uint32_t AddreSize, uint32_t Address,
+                       StringRef Bytes) = 0;
+
+  /// Emit the debug_loc contribution for \p Unit by copying the entries from
+  /// \p Dwarf and offsetting them. Update the location attributes to point to
+  /// the new entries.
+  virtual void emitLocationsForUnit(
+      const CompileUnit &Unit, DWARFContext &Dwarf,
+      std::function<void(StringRef, SmallVectorImpl<uint8_t> &)>
+          ProcessExpr) = 0;
+
+  /// Emit the compilation unit header for \p Unit in the
+  /// debug_info section.
+  ///
+  /// As a side effect, this also switches the current Dwarf version
+  /// of the MC layer to the one of U.getOrigUnit().
+  virtual void emitCompileUnitHeader(CompileUnit &Unit) = 0;
+
+  /// Recursively emit the DIE tree rooted at \p Die.
+  virtual void emitDIE(DIE &Die) = 0;
+
+  /// Returns size of generated .debug_line section.
+  virtual uint64_t getLineSectionSize() const = 0;
+
+  /// Returns size of generated .debug_frame section.
+  virtual uint64_t getFrameSectionSize() const = 0;
+
+  /// Returns size of generated .debug_ranges section.
+  virtual uint64_t getRangesSectionSize() const = 0;
+
+  /// Returns size of generated .debug_info section.
+  virtual uint64_t getDebugInfoSectionSize() const = 0;
+};
+
 } // end namespace llvm
 
 #endif // LLVM_DWARFLINKER_DWARFLINKER_H