[llvm-dwarfdump] - Teach dwarfdump to decompress debug sections in zlib style.

Before this llvm-dwarfdump only recognized zlib-gnu compression style of headers,
this patch adds support for zlib style. 
It looks reasonable to support both styles for dumping,
even if we are not going to suport generating of deprecated gnu one.

Differential revision: http://reviews.llvm.org/D20470

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270540 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 14 insertions, 0 deletions

diff --git a/include/llvm/Object/COFF.h b/include/llvm/Object/COFF.h
index 7553f4bdaf7..aa12418f2d3 100644
--- a/include/llvm/Object/COFF.h
+++ b/include/llvm/Object/COFF.h
@@ -694,6 +694,7 @@ protected:
   std::error_code getSectionContents(DataRefImpl Sec,
                                      StringRef &Res) const override;
   uint64_t getSectionAlignment(DataRefImpl Sec) const override;
+  bool isSectionCompressed(DataRefImpl Sec) const override;
   bool isSectionText(DataRefImpl Sec) const override;
   bool isSectionData(DataRefImpl Sec) const override;
   bool isSectionBSS(DataRefImpl Sec) const override;
diff --git a/include/llvm/Object/ELFObjectFile.h b/include/llvm/Object/ELFObjectFile.h
index c5f777186aa..52cde1a0f0f 100644
--- a/include/llvm/Object/ELFObjectFile.h
+++ b/include/llvm/Object/ELFObjectFile.h
@@ -222,6 +222,7 @@ protected:
   std::error_code getSectionContents(DataRefImpl Sec,
                                      StringRef &Res) const override;
   uint64_t getSectionAlignment(DataRefImpl Sec) const override;
+  bool isSectionCompressed(DataRefImpl Sec) const override;
   bool isSectionText(DataRefImpl Sec) const override;
   bool isSectionData(DataRefImpl Sec) const override;
   bool isSectionBSS(DataRefImpl Sec) const override;
@@ -584,6 +585,11 @@ uint64_t ELFObjectFile<ELFT>::getSectionAlignment(DataRefImpl Sec) const {
 }
 
 template <class ELFT>
+bool ELFObjectFile<ELFT>::isSectionCompressed(DataRefImpl Sec) const {
+  return getSection(Sec)->sh_flags & ELF::SHF_COMPRESSED;
+}
+
+template <class ELFT>
 bool ELFObjectFile<ELFT>::isSectionText(DataRefImpl Sec) const {
   return getSection(Sec)->sh_flags & ELF::SHF_EXECINSTR;
 }
diff --git a/include/llvm/Object/MachO.h b/include/llvm/Object/MachO.h
index 611acf3124d..6a079a964bf 100644
--- a/include/llvm/Object/MachO.h
+++ b/include/llvm/Object/MachO.h
@@ -222,6 +222,7 @@ public:
   std::error_code getSectionContents(DataRefImpl Sec,
                                      StringRef &Res) const override;
   uint64_t getSectionAlignment(DataRefImpl Sec) const override;
+  bool isSectionCompressed(DataRefImpl Sec) const override;
   bool isSectionText(DataRefImpl Sec) const override;
   bool isSectionData(DataRefImpl Sec) const override;
   bool isSectionBSS(DataRefImpl Sec) const override;
diff --git a/include/llvm/Object/ObjectFile.h b/include/llvm/Object/ObjectFile.h
index 0a902a4590a..0f0f10b8c19 100644
--- a/include/llvm/Object/ObjectFile.h
+++ b/include/llvm/Object/ObjectFile.h
@@ -89,6 +89,7 @@ public:
   /// @brief Get the alignment of this section as the actual value (not log 2).
   uint64_t getAlignment() const;
 
+  bool isCompressed() const;
   bool isText() const;
   bool isData() const;
   bool isBSS() const;
@@ -214,6 +215,7 @@ protected:
   virtual std::error_code getSectionContents(DataRefImpl Sec,
                                              StringRef &Res) const = 0;
   virtual uint64_t getSectionAlignment(DataRefImpl Sec) const = 0;
+  virtual bool isSectionCompressed(DataRefImpl Sec) const = 0;
   virtual bool isSectionText(DataRefImpl Sec) const = 0;
   virtual bool isSectionData(DataRefImpl Sec) const = 0;
   virtual bool isSectionBSS(DataRefImpl Sec) const = 0;
@@ -380,6 +382,10 @@ inline uint64_t SectionRef::getAlignment() const {
   return OwningObject->getSectionAlignment(SectionPimpl);
 }
 
+inline bool SectionRef::isCompressed() const {
+  return OwningObject->isSectionCompressed(SectionPimpl);
+}
+
 inline bool SectionRef::isText() const {
   return OwningObject->isSectionText(SectionPimpl);
 }