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/DWARFDebugInfoEntry.h b/lib/DebugInfo/DWARFDebugInfoEntry.h
new file mode 100644
index 0000000..aa2b89d
--- /dev/null
+++ b/lib/DebugInfo/DWARFDebugInfoEntry.h
@@ -0,0 +1,131 @@
+//===-- DWARFDebugInfoEntry.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_DWARFDEBUGINFOENTRY_H
+#define LLVM_DEBUGINFO_DWARFDEBUGINFOENTRY_H
+
+#include "DWARFAbbreviationDeclaration.h"
+#include "llvm/Support/DataTypes.h"
+
+namespace llvm {
+
+class DWARFCompileUnit;
+class DWARFContext;
+class DWARFFormValue;
+
+/// DWARFDebugInfoEntryMinimal - A DIE with only the minimum required data.
+class DWARFDebugInfoEntryMinimal {
+ /// Offset within the .debug_info of the start of this entry.
+ uint64_t Offset;
+
+ /// How many to subtract from "this" to get the parent.
+ /// If zero this die has no parent.
+ uint32_t ParentIdx;
+
+ /// How many to add to "this" to get the sibling.
+ uint32_t SiblingIdx;
+
+ const DWARFAbbreviationDeclaration *AbbrevDecl;
+public:
+ void dump(raw_ostream &OS, const DWARFCompileUnit *cu,
+ unsigned recurseDepth, unsigned indent = 0) const;
+ void dumpAttribute(raw_ostream &OS, const DWARFCompileUnit *cu,
+ uint32_t *offset_ptr, uint16_t attr, uint16_t form,
+ unsigned indent = 0) const;
+
+ bool extractFast(const DWARFCompileUnit *cu, const uint8_t *fixed_form_sizes,
+ uint32_t *offset_ptr);
+
+ /// Extract a debug info entry for a given compile unit from the
+ /// .debug_info and .debug_abbrev data starting at the given offset.
+ bool extract(const DWARFCompileUnit *cu, uint32_t *offset_ptr);
+
+ uint32_t getTag() const { return AbbrevDecl ? AbbrevDecl->getTag() : 0; }
+ bool isNULL() const { return AbbrevDecl == 0; }
+ uint64_t getOffset() const { return Offset; }
+ uint32_t getNumAttributes() const {
+ return !isNULL() ? AbbrevDecl->getNumAttributes() : 0;
+ }
+ bool hasChildren() const { return !isNULL() && AbbrevDecl->hasChildren(); }
+
+ // We know we are kept in a vector of contiguous entries, so we know
+ // our parent will be some index behind "this".
+ DWARFDebugInfoEntryMinimal *getParent() {
+ return ParentIdx > 0 ? this - ParentIdx : 0;
+ }
+ const DWARFDebugInfoEntryMinimal *getParent() const {
+ return ParentIdx > 0 ? this - ParentIdx : 0;
+ }
+ // We know we are kept in a vector of contiguous entries, so we know
+ // our sibling will be some index after "this".
+ DWARFDebugInfoEntryMinimal *getSibling() {
+ return SiblingIdx > 0 ? this + SiblingIdx : 0;
+ }
+ const DWARFDebugInfoEntryMinimal *getSibling() const {
+ return SiblingIdx > 0 ? this + SiblingIdx : 0;
+ }
+ // We know we are kept in a vector of contiguous entries, so we know
+ // we don't need to store our child pointer, if we have a child it will
+ // be the next entry in the list...
+ DWARFDebugInfoEntryMinimal *getFirstChild() {
+ return hasChildren() ? this + 1 : 0;
+ }
+ const DWARFDebugInfoEntryMinimal *getFirstChild() const {
+ return hasChildren() ? this + 1 : 0;
+ }
+
+ void setParent(DWARFDebugInfoEntryMinimal *parent) {
+ if (parent) {
+ // We know we are kept in a vector of contiguous entries, so we know
+ // our parent will be some index behind "this".
+ ParentIdx = this - parent;
+ }
+ else
+ ParentIdx = 0;
+ }
+ void setSibling(DWARFDebugInfoEntryMinimal *sibling) {
+ if (sibling)
+ {
+ // We know we are kept in a vector of contiguous entries, so we know
+ // our sibling will be some index after "this".
+ SiblingIdx = sibling - this;
+ sibling->setParent(getParent());
+ }
+ else
+ SiblingIdx = 0;
+ }
+
+ const DWARFAbbreviationDeclaration *getAbbreviationDeclarationPtr() const {
+ return AbbrevDecl;
+ }
+
+ uint32_t getAttributeValue(const DWARFCompileUnit *cu,
+ const uint16_t attr, DWARFFormValue &formValue,
+ uint32_t *end_attr_offset_ptr = 0) const;
+
+ const char* getAttributeValueAsString(const DWARFCompileUnit* cu,
+ const uint16_t attr,
+ const char *fail_value) const;
+
+ uint64_t getAttributeValueAsUnsigned(const DWARFCompileUnit *cu,
+ const uint16_t attr,
+ uint64_t fail_value) const;
+
+ uint64_t getAttributeValueAsReference(const DWARFCompileUnit *cu,
+ const uint16_t attr,
+ uint64_t fail_value) const;
+
+ int64_t getAttributeValueAsSigned(const DWARFCompileUnit* cu,
+ const uint16_t attr,
+ int64_t fail_value) const;
+};
+
+}
+
+#endif