Sketch out a DWARF parser.
This introduces a new library to LLVM: libDebugInfo. It will provide debug information
parsing to LLVM. Much of the design and some of the code is taken from the LLDB project.
It also contains an llvm-dwarfdump tool that can dump the abbrevs and DIEs from an
object file. It can be used to write tests for DWARF input and output easily.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139627 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/DebugInfo/DWARFContext.h b/lib/DebugInfo/DWARFContext.h
new file mode 100644
index 0000000..1a70f3f
--- /dev/null
+++ b/lib/DebugInfo/DWARFContext.h
@@ -0,0 +1,104 @@
+//===-- DWARFContext.h ------------------------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===/
+
+#ifndef LLVM_DEBUGINFO_DWARFCONTEXT_H
+#define LLVM_DEBUGINFO_DWARFCONTEXT_H
+
+#include "DWARFCompileUnit.h"
+#include "llvm/DebugInfo/DIContext.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/SmallVector.h"
+
+namespace llvm {
+
+class DWARFDebugAbbrev;
+
+/// DWARFContext
+/// This data structure is the top level entity that deals with dwarf debug
+/// information parsing. The actual data is supplied through pure virtual
+/// methods that a concrete implementation provides.
+class DWARFContext : public DIContext {
+ bool IsLittleEndian;
+
+ SmallVector<DWARFCompileUnit, 1> CUs;
+ OwningPtr<DWARFDebugAbbrev> Abbrev;
+
+ DWARFContext(DWARFContext &); // = delete
+ DWARFContext &operator=(DWARFContext &); // = delete
+
+ /// Read compile units from the debug_info section and store them in CUs.
+ void parseCompileUnits();
+protected:
+ DWARFContext(bool isLittleEndian) : IsLittleEndian(isLittleEndian) {}
+public:
+ virtual void dump(raw_ostream &OS);
+ /// Get the number of compile units in this context.
+ unsigned getNumCompileUnits() {
+ if (CUs.empty())
+ parseCompileUnits();
+ return CUs.size();
+ }
+ /// Get the compile unit at the specified index for this compile unit.
+ DWARFCompileUnit *getCompileUnitAtIndex(unsigned index) {
+ if (CUs.empty())
+ parseCompileUnits();
+ return &CUs[index];
+ }
+
+ /// Get a pointer to the parsed DebugAbbrev object.
+ const DWARFDebugAbbrev *getDebugAbbrev();
+
+ bool isLittleEndian() const { return IsLittleEndian; }
+
+ virtual StringRef getInfoSection() = 0;
+ virtual StringRef getAbbrevSection() = 0;
+ virtual StringRef getARangeSection() = 0;
+ virtual StringRef getLineSection() = 0;
+ virtual StringRef getStringSection() = 0;
+
+ static bool isSupportedVersion(unsigned version) {
+ return version == 2 || version == 3;
+ }
+};
+
+
+/// DWARFContextInMemory is the simplest possible implementation of a
+/// DWARFContext. It assumes all content is available in memory and stores
+/// pointers to it.
+class DWARFContextInMemory : public DWARFContext {
+ StringRef InfoSection;
+ StringRef AbbrevSection;
+ StringRef ARangeSection;
+ StringRef LineSection;
+ StringRef StringSection;
+public:
+ DWARFContextInMemory(bool isLittleEndian,
+ StringRef infoSection,
+ StringRef abbrevSection,
+ StringRef aRangeSection,
+ StringRef lineSection,
+ StringRef stringSection)
+ : DWARFContext(isLittleEndian),
+ InfoSection(infoSection),
+ AbbrevSection(abbrevSection),
+ ARangeSection(aRangeSection),
+ LineSection(lineSection),
+ StringSection(stringSection)
+ {}
+
+ virtual StringRef getInfoSection() { return InfoSection; }
+ virtual StringRef getAbbrevSection() { return AbbrevSection; }
+ virtual StringRef getARangeSection() { return ARangeSection; }
+ virtual StringRef getLineSection() { return LineSection; }
+ virtual StringRef getStringSection() { return StringSection; }
+};
+
+}
+
+#endif