[llvm] 29d253c - [Object] Add the method for checking if a section is a debug section

[Djordje Todorovic via llvm-commits]

Author: Djordje Todorovic
Date: 2020-04-02T10:56:00+02:00
New Revision: 29d253c4c6879bfe57040c8c59b0d9d84f6e5e2f

URL: https://github.com/llvm/llvm-project/commit/29d253c4c6879bfe57040c8c59b0d9d84f6e5e2f
DIFF: https://github.com/llvm/llvm-project/commit/29d253c4c6879bfe57040c8c59b0d9d84f6e5e2f.diff

LOG: [Object] Add the method for checking if a section is a debug section

Different file formats have different naming style for the debug
sections. The method is implemented for ELF, COFF and Mach-O formats.

Differential Revision: https://reviews.llvm.org/D76276

Added: 
    

Modified: 
    llvm/include/llvm/Object/COFF.h
    llvm/include/llvm/Object/ELFObjectFile.h
    llvm/include/llvm/Object/MachO.h
    llvm/include/llvm/Object/ObjectFile.h
    llvm/lib/Object/COFFObjectFile.cpp
    llvm/lib/Object/MachOObjectFile.cpp
    llvm/lib/Object/ObjectFile.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Object/COFF.h b/llvm/include/llvm/Object/COFF.h
index b91ee5887fec..f1386924ecca 100644
--- a/llvm/include/llvm/Object/COFF.h
+++ b/llvm/include/llvm/Object/COFF.h
@@ -912,6 +912,7 @@ class COFFObjectFile : public ObjectFile {
   bool isSectionData(DataRefImpl Sec) const override;
   bool isSectionBSS(DataRefImpl Sec) const override;
   bool isSectionVirtual(DataRefImpl Sec) const override;
+  bool isDebugSection(StringRef SectionName) const override;
   relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
   relocation_iterator section_rel_end(DataRefImpl Sec) const override;
 

diff  --git a/llvm/include/llvm/Object/ELFObjectFile.h b/llvm/include/llvm/Object/ELFObjectFile.h
index de18b7955c24..5c10badda394 100644
--- a/llvm/include/llvm/Object/ELFObjectFile.h
+++ b/llvm/include/llvm/Object/ELFObjectFile.h
@@ -285,6 +285,7 @@ template <class ELFT> class ELFObjectFile : public ELFObjectFileBase {
   bool isSectionVirtual(DataRefImpl Sec) const override;
   bool isBerkeleyText(DataRefImpl Sec) const override;
   bool isBerkeleyData(DataRefImpl Sec) const override;
+  bool isDebugSection(StringRef SectionName) const override;
   relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
   relocation_iterator section_rel_end(DataRefImpl Sec) const override;
   std::vector<SectionRef> dynamic_relocation_sections() const override;
@@ -813,6 +814,12 @@ bool ELFObjectFile<ELFT>::isBerkeleyData(DataRefImpl Sec) const {
          EShdr->sh_flags & ELF::SHF_ALLOC;
 }
 
+template <class ELFT>
+bool ELFObjectFile<ELFT>::isDebugSection(StringRef SectionName) const {
+  return SectionName.startswith(".debug") ||
+         SectionName.startswith(".zdebug") || SectionName == ".gdb_index";
+}
+
 template <class ELFT>
 relocation_iterator
 ELFObjectFile<ELFT>::section_rel_begin(DataRefImpl Sec) const {

diff  --git a/llvm/include/llvm/Object/MachO.h b/llvm/include/llvm/Object/MachO.h
index 380e3908d9da..351ee419d6aa 100644
--- a/llvm/include/llvm/Object/MachO.h
+++ b/llvm/include/llvm/Object/MachO.h
@@ -309,6 +309,7 @@ class MachOObjectFile : public ObjectFile {
   bool isSectionBSS(DataRefImpl Sec) const override;
   bool isSectionVirtual(DataRefImpl Sec) const override;
   bool isSectionBitcode(DataRefImpl Sec) const override;
+  bool isDebugSection(StringRef SectionName) const override;
 
   /// When dsymutil generates the companion file, it strips all unnecessary
   /// sections (e.g. everything in the _TEXT segment) by omitting their body

diff  --git a/llvm/include/llvm/Object/ObjectFile.h b/llvm/include/llvm/Object/ObjectFile.h
index 2f1493457605..ef82c057012f 100644
--- a/llvm/include/llvm/Object/ObjectFile.h
+++ b/llvm/include/llvm/Object/ObjectFile.h
@@ -123,6 +123,9 @@ class SectionRef {
   /// contains data (e.g. PROGBITS), but is not text.
   bool isBerkeleyData() const;
 
+  /// Whether this section is a debug section.
+  bool isDebugSection(StringRef SectionName) const;
+
   bool containsSymbol(SymbolRef S) const;
 
   relocation_iterator relocation_begin() const;
@@ -272,6 +275,7 @@ class ObjectFile : public SymbolicFile {
   virtual bool isSectionStripped(DataRefImpl Sec) const;
   virtual bool isBerkeleyText(DataRefImpl Sec) const;
   virtual bool isBerkeleyData(DataRefImpl Sec) const;
+  virtual bool isDebugSection(StringRef SectionName) const;
   virtual relocation_iterator section_rel_begin(DataRefImpl Sec) const = 0;
   virtual relocation_iterator section_rel_end(DataRefImpl Sec) const = 0;
   virtual Expected<section_iterator> getRelocatedSection(DataRefImpl Sec) const;
@@ -495,6 +499,10 @@ inline bool SectionRef::isBerkeleyData() const {
   return OwningObject->isBerkeleyData(SectionPimpl);
 }
 
+inline bool SectionRef::isDebugSection(StringRef SectionName) const {
+  return OwningObject->isDebugSection(SectionName);
+}
+
 inline relocation_iterator SectionRef::relocation_begin() const {
   return OwningObject->section_rel_begin(SectionPimpl);
 }

diff  --git a/llvm/lib/Object/COFFObjectFile.cpp b/llvm/lib/Object/COFFObjectFile.cpp
index 384c19d4fb1a..1fd95451e72d 100644
--- a/llvm/lib/Object/COFFObjectFile.cpp
+++ b/llvm/lib/Object/COFFObjectFile.cpp
@@ -328,6 +328,12 @@ bool COFFObjectFile::isSectionBSS(DataRefImpl Ref) const {
   return (Sec->Characteristics & BssFlags) == BssFlags;
 }
 
+// The .debug sections are the only debug sections for COFF
+// (\see MCObjectFileInfo.cpp).
+bool COFFObjectFile::isDebugSection(StringRef SectionName) const {
+  return SectionName.startswith(".debug");
+}
+
 unsigned COFFObjectFile::getSectionID(SectionRef Sec) const {
   uintptr_t Offset =
       uintptr_t(Sec.getRawDataRefImpl().p) - uintptr_t(SectionTable);

diff  --git a/llvm/lib/Object/MachOObjectFile.cpp b/llvm/lib/Object/MachOObjectFile.cpp
index feea11cafbac..c0aa0b8b3ee3 100644
--- a/llvm/lib/Object/MachOObjectFile.cpp
+++ b/llvm/lib/Object/MachOObjectFile.cpp
@@ -2030,6 +2030,11 @@ bool MachOObjectFile::isSectionBSS(DataRefImpl Sec) const {
           SectionType == MachO::S_GB_ZEROFILL);
 }
 
+bool MachOObjectFile::isDebugSection(StringRef SectionName) const {
+  return SectionName.startswith("__debug") ||
+         SectionName.startswith("__zdebug") || SectionName == "__gdb_index";
+}
+
 unsigned MachOObjectFile::getSectionID(SectionRef Sec) const {
   return Sec.getRawDataRefImpl().d.a;
 }

diff  --git a/llvm/lib/Object/ObjectFile.cpp b/llvm/lib/Object/ObjectFile.cpp
index 7879e2ef651c..1453f9d88130 100644
--- a/llvm/lib/Object/ObjectFile.cpp
+++ b/llvm/lib/Object/ObjectFile.cpp
@@ -91,6 +91,10 @@ bool ObjectFile::isBerkeleyData(DataRefImpl Sec) const {
   return isSectionData(Sec);
 }
 
+bool ObjectFile::isDebugSection(StringRef SectionName) const {
+  return false;
+}
+
 Expected<section_iterator>
 ObjectFile::getRelocatedSection(DataRefImpl Sec) const {
   return section_iterator(SectionRef(Sec, this));