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https://github.com/c64scene-ar/llvm-6502.git
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401c02a7ed
Use `DIEValueList` as a pointer to either `DIEBlock` or `DIELoc` instead of `DIE`, since soon they won't inherit from the latter. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243857 91177308-0d34-0410-b5e6-96231b3b80d8
3151 lines
121 KiB
C++
3151 lines
121 KiB
C++
//===- tools/dsymutil/DwarfLinker.cpp - Dwarf debug info linker -----------===//
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//
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// The LLVM Linker
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "DebugMap.h"
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#include "BinaryHolder.h"
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#include "DebugMap.h"
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#include "dsymutil.h"
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#include "llvm/ADT/IntervalMap.h"
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#include "llvm/ADT/StringMap.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/CodeGen/AsmPrinter.h"
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#include "llvm/CodeGen/DIE.h"
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#include "llvm/Config/config.h"
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#include "llvm/DebugInfo/DWARF/DWARFContext.h"
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#include "llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h"
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#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
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#include "llvm/MC/MCAsmBackend.h"
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#include "llvm/MC/MCAsmInfo.h"
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#include "llvm/MC/MCContext.h"
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#include "llvm/MC/MCCodeEmitter.h"
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#include "llvm/MC/MCDwarf.h"
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#include "llvm/MC/MCInstrInfo.h"
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#include "llvm/MC/MCObjectFileInfo.h"
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#include "llvm/MC/MCRegisterInfo.h"
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#include "llvm/MC/MCStreamer.h"
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#include "llvm/MC/MCSubtargetInfo.h"
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#include "llvm/Object/MachO.h"
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#include "llvm/Support/Dwarf.h"
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#include "llvm/Support/LEB128.h"
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#include "llvm/Support/TargetRegistry.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetOptions.h"
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#include <string>
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#include <tuple>
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namespace llvm {
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namespace dsymutil {
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namespace {
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void warn(const Twine &Warning, const Twine &Context) {
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errs() << Twine("while processing ") + Context + ":\n";
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errs() << Twine("warning: ") + Warning + "\n";
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}
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bool error(const Twine &Error, const Twine &Context) {
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errs() << Twine("while processing ") + Context + ":\n";
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errs() << Twine("error: ") + Error + "\n";
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return false;
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}
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template <typename KeyT, typename ValT>
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using HalfOpenIntervalMap =
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IntervalMap<KeyT, ValT, IntervalMapImpl::NodeSizer<KeyT, ValT>::LeafSize,
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IntervalMapHalfOpenInfo<KeyT>>;
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typedef HalfOpenIntervalMap<uint64_t, int64_t> FunctionIntervals;
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// FIXME: Delete this structure.
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struct PatchLocation {
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DIE::value_iterator I;
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PatchLocation() = default;
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PatchLocation(DIE::value_iterator I) : I(I) {}
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void set(uint64_t New) const {
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assert(I);
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const auto &Old = *I;
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assert(Old.getType() == DIEValue::isInteger);
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*I = DIEValue(Old.getAttribute(), Old.getForm(), DIEInteger(New));
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}
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uint64_t get() const {
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assert(I);
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return I->getDIEInteger().getValue();
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}
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};
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class CompileUnit;
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struct DeclMapInfo;
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class NonRelocatableStringpool;
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/// A DeclContext is a named program scope that is used for ODR
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/// uniquing of types.
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/// The set of DeclContext for the ODR-subject parts of a Dwarf link
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/// is expanded (and uniqued) with each new object file processed. We
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/// need to determine the context of each DIE in an linked object file
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/// to see if the corresponding type has already been emitted.
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///
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/// The contexts are conceptually organised as a tree (eg. a function
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/// scope is contained in a namespace scope that contains other
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/// scopes), but storing/accessing them in an actual tree is too
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/// inefficient: we need to be able to very quickly query a context
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/// for a given child context by name. Storing a StringMap in each
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/// DeclContext would be too space inefficient.
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/// The solution here is to give each DeclContext a link to its parent
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/// (this allows to walk up the tree), but to query the existance of a
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/// specific DeclContext using a separate DenseMap keyed on the hash
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/// of the fully qualified name of the context.
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class DeclContext {
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unsigned QualifiedNameHash;
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uint32_t Line;
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uint32_t ByteSize;
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uint16_t Tag;
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StringRef Name;
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StringRef File;
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const DeclContext &Parent;
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const DWARFDebugInfoEntryMinimal *LastSeenDIE;
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uint32_t LastSeenCompileUnitID;
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uint32_t CanonicalDIEOffset;
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friend DeclMapInfo;
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public:
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typedef DenseSet<DeclContext *, DeclMapInfo> Map;
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DeclContext()
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: QualifiedNameHash(0), Line(0), ByteSize(0),
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Tag(dwarf::DW_TAG_compile_unit), Name(), File(), Parent(*this),
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LastSeenDIE(nullptr), LastSeenCompileUnitID(0), CanonicalDIEOffset(0) {}
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DeclContext(unsigned Hash, uint32_t Line, uint32_t ByteSize, uint16_t Tag,
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StringRef Name, StringRef File, const DeclContext &Parent,
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const DWARFDebugInfoEntryMinimal *LastSeenDIE = nullptr,
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unsigned CUId = 0)
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: QualifiedNameHash(Hash), Line(Line), ByteSize(ByteSize), Tag(Tag),
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Name(Name), File(File), Parent(Parent), LastSeenDIE(LastSeenDIE),
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LastSeenCompileUnitID(CUId), CanonicalDIEOffset(0) {}
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uint32_t getQualifiedNameHash() const { return QualifiedNameHash; }
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bool setLastSeenDIE(CompileUnit &U, const DWARFDebugInfoEntryMinimal *Die);
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uint32_t getCanonicalDIEOffset() const { return CanonicalDIEOffset; }
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void setCanonicalDIEOffset(uint32_t Offset) { CanonicalDIEOffset = Offset; }
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uint16_t getTag() const { return Tag; }
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StringRef getName() const { return Name; }
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};
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/// Info type for the DenseMap storing the DeclContext pointers.
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struct DeclMapInfo : private DenseMapInfo<DeclContext *> {
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using DenseMapInfo<DeclContext *>::getEmptyKey;
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using DenseMapInfo<DeclContext *>::getTombstoneKey;
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static unsigned getHashValue(const DeclContext *Ctxt) {
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return Ctxt->QualifiedNameHash;
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}
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static bool isEqual(const DeclContext *LHS, const DeclContext *RHS) {
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if (RHS == getEmptyKey() || RHS == getTombstoneKey())
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return RHS == LHS;
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return LHS->QualifiedNameHash == RHS->QualifiedNameHash &&
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LHS->Line == RHS->Line && LHS->ByteSize == RHS->ByteSize &&
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LHS->Name.data() == RHS->Name.data() &&
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LHS->File.data() == RHS->File.data() &&
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LHS->Parent.QualifiedNameHash == RHS->Parent.QualifiedNameHash;
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}
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};
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/// This class gives a tree-like API to the DenseMap that stores the
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/// DeclContext objects. It also holds the BumpPtrAllocator where
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/// these objects will be allocated.
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class DeclContextTree {
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BumpPtrAllocator Allocator;
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DeclContext Root;
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DeclContext::Map Contexts;
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public:
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/// Get the child of \a Context described by \a DIE in \a Unit. The
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/// required strings will be interned in \a StringPool.
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/// \returns The child DeclContext along with one bit that is set if
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/// this context is invalid.
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/// FIXME: the invalid bit along the return value is to emulate some
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/// dsymutil-classic functionality. See the fucntion definition for
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/// a more thorough discussion of its use.
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PointerIntPair<DeclContext *, 1>
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getChildDeclContext(DeclContext &Context,
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const DWARFDebugInfoEntryMinimal *DIE, CompileUnit &Unit,
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NonRelocatableStringpool &StringPool);
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DeclContext &getRoot() { return Root; }
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};
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/// \brief Stores all information relating to a compile unit, be it in
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/// its original instance in the object file to its brand new cloned
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/// and linked DIE tree.
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class CompileUnit {
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public:
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/// \brief Information gathered about a DIE in the object file.
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struct DIEInfo {
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int64_t AddrAdjust; ///< Address offset to apply to the described entity.
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DeclContext *Ctxt; ///< ODR Declaration context.
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DIE *Clone; ///< Cloned version of that DIE.
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uint32_t ParentIdx; ///< The index of this DIE's parent.
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bool Keep; ///< Is the DIE part of the linked output?
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bool InDebugMap; ///< Was this DIE's entity found in the map?
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};
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CompileUnit(DWARFUnit &OrigUnit, unsigned ID, bool CanUseODR)
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: OrigUnit(OrigUnit), ID(ID), LowPc(UINT64_MAX), HighPc(0), RangeAlloc(),
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Ranges(RangeAlloc) {
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Info.resize(OrigUnit.getNumDIEs());
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const auto *CUDie = OrigUnit.getUnitDIE(false);
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unsigned Lang = CUDie->getAttributeValueAsUnsignedConstant(
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&OrigUnit, dwarf::DW_AT_language, 0);
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HasODR = CanUseODR && (Lang == dwarf::DW_LANG_C_plus_plus ||
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Lang == dwarf::DW_LANG_C_plus_plus_03 ||
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Lang == dwarf::DW_LANG_C_plus_plus_11 ||
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Lang == dwarf::DW_LANG_C_plus_plus_14 ||
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Lang == dwarf::DW_LANG_ObjC_plus_plus);
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}
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CompileUnit(CompileUnit &&RHS)
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: OrigUnit(RHS.OrigUnit), Info(std::move(RHS.Info)),
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CUDie(std::move(RHS.CUDie)), StartOffset(RHS.StartOffset),
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NextUnitOffset(RHS.NextUnitOffset), RangeAlloc(), Ranges(RangeAlloc) {
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// The CompileUnit container has been 'reserve()'d with the right
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// size. We cannot move the IntervalMap anyway.
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llvm_unreachable("CompileUnits should not be moved.");
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}
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DWARFUnit &getOrigUnit() const { return OrigUnit; }
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unsigned getUniqueID() const { return ID; }
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DIE *getOutputUnitDIE() const { return CUDie; }
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void setOutputUnitDIE(DIE *Die) { CUDie = Die; }
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bool hasODR() const { return HasODR; }
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DIEInfo &getInfo(unsigned Idx) { return Info[Idx]; }
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const DIEInfo &getInfo(unsigned Idx) const { return Info[Idx]; }
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uint64_t getStartOffset() const { return StartOffset; }
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uint64_t getNextUnitOffset() const { return NextUnitOffset; }
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void setStartOffset(uint64_t DebugInfoSize) { StartOffset = DebugInfoSize; }
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uint64_t getLowPc() const { return LowPc; }
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uint64_t getHighPc() const { return HighPc; }
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Optional<PatchLocation> getUnitRangesAttribute() const {
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return UnitRangeAttribute;
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}
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const FunctionIntervals &getFunctionRanges() const { return Ranges; }
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const std::vector<PatchLocation> &getRangesAttributes() const {
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return RangeAttributes;
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}
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const std::vector<std::pair<PatchLocation, int64_t>> &
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getLocationAttributes() const {
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return LocationAttributes;
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}
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/// \brief Compute the end offset for this unit. Must be
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/// called after the CU's DIEs have been cloned.
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/// \returns the next unit offset (which is also the current
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/// debug_info section size).
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uint64_t computeNextUnitOffset();
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/// \brief Keep track of a forward reference to DIE \p Die in \p
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/// RefUnit by \p Attr. The attribute should be fixed up later to
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/// point to the absolute offset of \p Die in the debug_info section
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/// or to the canonical offset of \p Ctxt if it is non-null.
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void noteForwardReference(DIE *Die, const CompileUnit *RefUnit,
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DeclContext *Ctxt, PatchLocation Attr);
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/// \brief Apply all fixups recored by noteForwardReference().
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void fixupForwardReferences();
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/// \brief Add a function range [\p LowPC, \p HighPC) that is
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/// relocatad by applying offset \p PCOffset.
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void addFunctionRange(uint64_t LowPC, uint64_t HighPC, int64_t PCOffset);
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/// \brief Keep track of a DW_AT_range attribute that we will need to
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/// patch up later.
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void noteRangeAttribute(const DIE &Die, PatchLocation Attr);
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/// \brief Keep track of a location attribute pointing to a location
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/// list in the debug_loc section.
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void noteLocationAttribute(PatchLocation Attr, int64_t PcOffset);
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/// \brief Add a name accelerator entry for \p Die with \p Name
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/// which is stored in the string table at \p Offset.
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void addNameAccelerator(const DIE *Die, const char *Name, uint32_t Offset,
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bool SkipPubnamesSection = false);
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/// \brief Add a type accelerator entry for \p Die with \p Name
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/// which is stored in the string table at \p Offset.
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void addTypeAccelerator(const DIE *Die, const char *Name, uint32_t Offset);
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struct AccelInfo {
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StringRef Name; ///< Name of the entry.
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const DIE *Die; ///< DIE this entry describes.
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uint32_t NameOffset; ///< Offset of Name in the string pool.
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bool SkipPubSection; ///< Emit this entry only in the apple_* sections.
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AccelInfo(StringRef Name, const DIE *Die, uint32_t NameOffset,
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bool SkipPubSection = false)
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: Name(Name), Die(Die), NameOffset(NameOffset),
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SkipPubSection(SkipPubSection) {}
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};
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const std::vector<AccelInfo> &getPubnames() const { return Pubnames; }
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const std::vector<AccelInfo> &getPubtypes() const { return Pubtypes; }
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/// Get the full path for file \a FileNum in the line table
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const char *getResolvedPath(unsigned FileNum) {
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if (FileNum >= ResolvedPaths.size())
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return nullptr;
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return ResolvedPaths[FileNum].size() ? ResolvedPaths[FileNum].c_str()
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: nullptr;
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}
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/// Set the fully resolved path for the line-table's file \a FileNum
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/// to \a Path.
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void setResolvedPath(unsigned FileNum, const std::string &Path) {
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if (ResolvedPaths.size() <= FileNum)
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ResolvedPaths.resize(FileNum + 1);
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ResolvedPaths[FileNum] = Path;
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}
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private:
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DWARFUnit &OrigUnit;
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unsigned ID;
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std::vector<DIEInfo> Info; ///< DIE info indexed by DIE index.
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DIE *CUDie; ///< Root of the linked DIE tree.
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uint64_t StartOffset;
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uint64_t NextUnitOffset;
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uint64_t LowPc;
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uint64_t HighPc;
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/// \brief A list of attributes to fixup with the absolute offset of
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/// a DIE in the debug_info section.
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///
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/// The offsets for the attributes in this array couldn't be set while
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/// cloning because for cross-cu forward refences the target DIE's
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/// offset isn't known you emit the reference attribute.
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std::vector<std::tuple<DIE *, const CompileUnit *, DeclContext *,
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PatchLocation>> ForwardDIEReferences;
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FunctionIntervals::Allocator RangeAlloc;
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/// \brief The ranges in that interval map are the PC ranges for
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/// functions in this unit, associated with the PC offset to apply
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/// to the addresses to get the linked address.
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FunctionIntervals Ranges;
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/// \brief DW_AT_ranges attributes to patch after we have gathered
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/// all the unit's function addresses.
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/// @{
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std::vector<PatchLocation> RangeAttributes;
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Optional<PatchLocation> UnitRangeAttribute;
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/// @}
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/// \brief Location attributes that need to be transfered from th
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/// original debug_loc section to the liked one. They are stored
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/// along with the PC offset that is to be applied to their
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/// function's address.
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std::vector<std::pair<PatchLocation, int64_t>> LocationAttributes;
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/// \brief Accelerator entries for the unit, both for the pub*
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/// sections and the apple* ones.
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/// @{
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std::vector<AccelInfo> Pubnames;
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std::vector<AccelInfo> Pubtypes;
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/// @}
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/// Cached resolved paths from the line table.
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std::vector<std::string> ResolvedPaths;
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/// Is this unit subject to the ODR rule?
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bool HasODR;
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};
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uint64_t CompileUnit::computeNextUnitOffset() {
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NextUnitOffset = StartOffset + 11 /* Header size */;
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// The root DIE might be null, meaning that the Unit had nothing to
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// contribute to the linked output. In that case, we will emit the
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// unit header without any actual DIE.
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if (CUDie)
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NextUnitOffset += CUDie->getSize();
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return NextUnitOffset;
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}
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/// \brief Keep track of a forward cross-cu reference from this unit
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/// to \p Die that lives in \p RefUnit.
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void CompileUnit::noteForwardReference(DIE *Die, const CompileUnit *RefUnit,
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DeclContext *Ctxt, PatchLocation Attr) {
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ForwardDIEReferences.emplace_back(Die, RefUnit, Ctxt, Attr);
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}
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/// \brief Apply all fixups recorded by noteForwardReference().
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void CompileUnit::fixupForwardReferences() {
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for (const auto &Ref : ForwardDIEReferences) {
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DIE *RefDie;
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const CompileUnit *RefUnit;
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PatchLocation Attr;
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DeclContext *Ctxt;
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std::tie(RefDie, RefUnit, Ctxt, Attr) = Ref;
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if (Ctxt && Ctxt->getCanonicalDIEOffset())
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Attr.set(Ctxt->getCanonicalDIEOffset());
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else
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Attr.set(RefDie->getOffset() + RefUnit->getStartOffset());
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}
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}
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void CompileUnit::addFunctionRange(uint64_t FuncLowPc, uint64_t FuncHighPc,
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int64_t PcOffset) {
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Ranges.insert(FuncLowPc, FuncHighPc, PcOffset);
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this->LowPc = std::min(LowPc, FuncLowPc + PcOffset);
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this->HighPc = std::max(HighPc, FuncHighPc + PcOffset);
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}
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void CompileUnit::noteRangeAttribute(const DIE &Die, PatchLocation Attr) {
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if (Die.getTag() != dwarf::DW_TAG_compile_unit)
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RangeAttributes.push_back(Attr);
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else
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UnitRangeAttribute = Attr;
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}
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void CompileUnit::noteLocationAttribute(PatchLocation Attr, int64_t PcOffset) {
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LocationAttributes.emplace_back(Attr, PcOffset);
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}
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/// \brief Add a name accelerator entry for \p Die with \p Name
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/// which is stored in the string table at \p Offset.
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void CompileUnit::addNameAccelerator(const DIE *Die, const char *Name,
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uint32_t Offset, bool SkipPubSection) {
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Pubnames.emplace_back(Name, Die, Offset, SkipPubSection);
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}
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/// \brief Add a type accelerator entry for \p Die with \p Name
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/// which is stored in the string table at \p Offset.
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void CompileUnit::addTypeAccelerator(const DIE *Die, const char *Name,
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uint32_t Offset) {
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Pubtypes.emplace_back(Name, Die, Offset, false);
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}
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/// \brief A string table that doesn't need relocations.
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///
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/// We are doing a final link, no need for a string table that
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/// has relocation entries for every reference to it. This class
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/// provides this ablitity by just associating offsets with
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/// strings.
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class NonRelocatableStringpool {
|
|
public:
|
|
/// \brief Entries are stored into the StringMap and simply linked
|
|
/// together through the second element of this pair in order to
|
|
/// keep track of insertion order.
|
|
typedef StringMap<std::pair<uint32_t, StringMapEntryBase *>, BumpPtrAllocator>
|
|
MapTy;
|
|
|
|
NonRelocatableStringpool()
|
|
: CurrentEndOffset(0), Sentinel(0), Last(&Sentinel) {
|
|
// Legacy dsymutil puts an empty string at the start of the line
|
|
// table.
|
|
getStringOffset("");
|
|
}
|
|
|
|
/// \brief Get the offset of string \p S in the string table. This
|
|
/// can insert a new element or return the offset of a preexisitng
|
|
/// one.
|
|
uint32_t getStringOffset(StringRef S);
|
|
|
|
/// \brief Get permanent storage for \p S (but do not necessarily
|
|
/// emit \p S in the output section).
|
|
/// \returns The StringRef that points to permanent storage to use
|
|
/// in place of \p S.
|
|
StringRef internString(StringRef S);
|
|
|
|
// \brief Return the first entry of the string table.
|
|
const MapTy::MapEntryTy *getFirstEntry() const {
|
|
return getNextEntry(&Sentinel);
|
|
}
|
|
|
|
// \brief Get the entry following \p E in the string table or null
|
|
// if \p E was the last entry.
|
|
const MapTy::MapEntryTy *getNextEntry(const MapTy::MapEntryTy *E) const {
|
|
return static_cast<const MapTy::MapEntryTy *>(E->getValue().second);
|
|
}
|
|
|
|
uint64_t getSize() { return CurrentEndOffset; }
|
|
|
|
private:
|
|
MapTy Strings;
|
|
uint32_t CurrentEndOffset;
|
|
MapTy::MapEntryTy Sentinel, *Last;
|
|
};
|
|
|
|
/// \brief Get the offset of string \p S in the string table. This
|
|
/// can insert a new element or return the offset of a preexisitng
|
|
/// one.
|
|
uint32_t NonRelocatableStringpool::getStringOffset(StringRef S) {
|
|
if (S.empty() && !Strings.empty())
|
|
return 0;
|
|
|
|
std::pair<uint32_t, StringMapEntryBase *> Entry(0, nullptr);
|
|
MapTy::iterator It;
|
|
bool Inserted;
|
|
|
|
// A non-empty string can't be at offset 0, so if we have an entry
|
|
// with a 0 offset, it must be a previously interned string.
|
|
std::tie(It, Inserted) = Strings.insert(std::make_pair(S, Entry));
|
|
if (Inserted || It->getValue().first == 0) {
|
|
// Set offset and chain at the end of the entries list.
|
|
It->getValue().first = CurrentEndOffset;
|
|
CurrentEndOffset += S.size() + 1; // +1 for the '\0'.
|
|
Last->getValue().second = &*It;
|
|
Last = &*It;
|
|
}
|
|
return It->getValue().first;
|
|
}
|
|
|
|
/// \brief Put \p S into the StringMap so that it gets permanent
|
|
/// storage, but do not actually link it in the chain of elements
|
|
/// that go into the output section. A latter call to
|
|
/// getStringOffset() with the same string will chain it though.
|
|
StringRef NonRelocatableStringpool::internString(StringRef S) {
|
|
std::pair<uint32_t, StringMapEntryBase *> Entry(0, nullptr);
|
|
auto InsertResult = Strings.insert(std::make_pair(S, Entry));
|
|
return InsertResult.first->getKey();
|
|
}
|
|
|
|
/// \brief The Dwarf streaming logic
|
|
///
|
|
/// All interactions with the MC layer that is used to build the debug
|
|
/// information binary representation are handled in this class.
|
|
class DwarfStreamer {
|
|
/// \defgroup MCObjects MC layer objects constructed by the streamer
|
|
/// @{
|
|
std::unique_ptr<MCRegisterInfo> MRI;
|
|
std::unique_ptr<MCAsmInfo> MAI;
|
|
std::unique_ptr<MCObjectFileInfo> MOFI;
|
|
std::unique_ptr<MCContext> MC;
|
|
MCAsmBackend *MAB; // Owned by MCStreamer
|
|
std::unique_ptr<MCInstrInfo> MII;
|
|
std::unique_ptr<MCSubtargetInfo> MSTI;
|
|
MCCodeEmitter *MCE; // Owned by MCStreamer
|
|
MCStreamer *MS; // Owned by AsmPrinter
|
|
std::unique_ptr<TargetMachine> TM;
|
|
std::unique_ptr<AsmPrinter> Asm;
|
|
/// @}
|
|
|
|
/// \brief the file we stream the linked Dwarf to.
|
|
std::unique_ptr<raw_fd_ostream> OutFile;
|
|
|
|
uint32_t RangesSectionSize;
|
|
uint32_t LocSectionSize;
|
|
uint32_t LineSectionSize;
|
|
uint32_t FrameSectionSize;
|
|
|
|
/// \brief Emit the pubnames or pubtypes section contribution for \p
|
|
/// Unit into \p Sec. The data is provided in \p Names.
|
|
void emitPubSectionForUnit(MCSection *Sec, StringRef Name,
|
|
const CompileUnit &Unit,
|
|
const std::vector<CompileUnit::AccelInfo> &Names);
|
|
|
|
public:
|
|
/// \brief Actually create the streamer and the ouptut file.
|
|
///
|
|
/// This could be done directly in the constructor, but it feels
|
|
/// more natural to handle errors through return value.
|
|
bool init(Triple TheTriple, StringRef OutputFilename);
|
|
|
|
/// \brief Dump the file to the disk.
|
|
bool finish();
|
|
|
|
AsmPrinter &getAsmPrinter() const { return *Asm; }
|
|
|
|
/// \brief Set the current output section to debug_info and change
|
|
/// the MC Dwarf version to \p DwarfVersion.
|
|
void switchToDebugInfoSection(unsigned DwarfVersion);
|
|
|
|
/// \brief 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().
|
|
void emitCompileUnitHeader(CompileUnit &Unit);
|
|
|
|
/// \brief Recursively emit the DIE tree rooted at \p Die.
|
|
void emitDIE(DIE &Die);
|
|
|
|
/// \brief Emit the abbreviation table \p Abbrevs to the
|
|
/// debug_abbrev section.
|
|
void emitAbbrevs(const std::vector<DIEAbbrev *> &Abbrevs);
|
|
|
|
/// \brief Emit the string table described by \p Pool.
|
|
void emitStrings(const NonRelocatableStringpool &Pool);
|
|
|
|
/// \brief Emit debug_ranges for \p FuncRange by translating the
|
|
/// original \p Entries.
|
|
void emitRangesEntries(
|
|
int64_t UnitPcOffset, uint64_t OrigLowPc,
|
|
FunctionIntervals::const_iterator FuncRange,
|
|
const std::vector<DWARFDebugRangeList::RangeListEntry> &Entries,
|
|
unsigned AddressSize);
|
|
|
|
/// \brief 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.
|
|
void emitUnitRangesEntries(CompileUnit &Unit, bool DoRangesSection);
|
|
|
|
uint32_t getRangesSectionSize() const { return RangesSectionSize; }
|
|
|
|
/// \brief Emit the debug_loc contribution for \p Unit by copying
|
|
/// the entries from \p Dwarf and offseting them. Update the
|
|
/// location attributes to point to the new entries.
|
|
void emitLocationsForUnit(const CompileUnit &Unit, DWARFContext &Dwarf);
|
|
|
|
/// \brief Emit the line table described in \p Rows into the
|
|
/// debug_line section.
|
|
void emitLineTableForUnit(StringRef PrologueBytes, unsigned MinInstLength,
|
|
std::vector<DWARFDebugLine::Row> &Rows,
|
|
unsigned AdddressSize);
|
|
|
|
uint32_t getLineSectionSize() const { return LineSectionSize; }
|
|
|
|
/// \brief Emit the .debug_pubnames contribution for \p Unit.
|
|
void emitPubNamesForUnit(const CompileUnit &Unit);
|
|
|
|
/// \brief Emit the .debug_pubtypes contribution for \p Unit.
|
|
void emitPubTypesForUnit(const CompileUnit &Unit);
|
|
|
|
/// \brief Emit a CIE.
|
|
void emitCIE(StringRef CIEBytes);
|
|
|
|
/// \brief Emit an FDE with data \p Bytes.
|
|
void emitFDE(uint32_t CIEOffset, uint32_t AddreSize, uint32_t Address,
|
|
StringRef Bytes);
|
|
|
|
uint32_t getFrameSectionSize() const { return FrameSectionSize; }
|
|
};
|
|
|
|
bool DwarfStreamer::init(Triple TheTriple, StringRef OutputFilename) {
|
|
std::string ErrorStr;
|
|
std::string TripleName;
|
|
StringRef Context = "dwarf streamer init";
|
|
|
|
// Get the target.
|
|
const Target *TheTarget =
|
|
TargetRegistry::lookupTarget(TripleName, TheTriple, ErrorStr);
|
|
if (!TheTarget)
|
|
return error(ErrorStr, Context);
|
|
TripleName = TheTriple.getTriple();
|
|
|
|
// Create all the MC Objects.
|
|
MRI.reset(TheTarget->createMCRegInfo(TripleName));
|
|
if (!MRI)
|
|
return error(Twine("no register info for target ") + TripleName, Context);
|
|
|
|
MAI.reset(TheTarget->createMCAsmInfo(*MRI, TripleName));
|
|
if (!MAI)
|
|
return error("no asm info for target " + TripleName, Context);
|
|
|
|
MOFI.reset(new MCObjectFileInfo);
|
|
MC.reset(new MCContext(MAI.get(), MRI.get(), MOFI.get()));
|
|
MOFI->InitMCObjectFileInfo(TheTriple, Reloc::Default, CodeModel::Default,
|
|
*MC);
|
|
|
|
MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "");
|
|
if (!MAB)
|
|
return error("no asm backend for target " + TripleName, Context);
|
|
|
|
MII.reset(TheTarget->createMCInstrInfo());
|
|
if (!MII)
|
|
return error("no instr info info for target " + TripleName, Context);
|
|
|
|
MSTI.reset(TheTarget->createMCSubtargetInfo(TripleName, "", ""));
|
|
if (!MSTI)
|
|
return error("no subtarget info for target " + TripleName, Context);
|
|
|
|
MCE = TheTarget->createMCCodeEmitter(*MII, *MRI, *MC);
|
|
if (!MCE)
|
|
return error("no code emitter for target " + TripleName, Context);
|
|
|
|
// Create the output file.
|
|
std::error_code EC;
|
|
OutFile =
|
|
llvm::make_unique<raw_fd_ostream>(OutputFilename, EC, sys::fs::F_None);
|
|
if (EC)
|
|
return error(Twine(OutputFilename) + ": " + EC.message(), Context);
|
|
|
|
MS = TheTarget->createMCObjectStreamer(TheTriple, *MC, *MAB, *OutFile, MCE,
|
|
*MSTI, false,
|
|
/*DWARFMustBeAtTheEnd*/ false);
|
|
if (!MS)
|
|
return error("no object streamer for target " + TripleName, Context);
|
|
|
|
// Finally create the AsmPrinter we'll use to emit the DIEs.
|
|
TM.reset(TheTarget->createTargetMachine(TripleName, "", "", TargetOptions()));
|
|
if (!TM)
|
|
return error("no target machine for target " + TripleName, Context);
|
|
|
|
Asm.reset(TheTarget->createAsmPrinter(*TM, std::unique_ptr<MCStreamer>(MS)));
|
|
if (!Asm)
|
|
return error("no asm printer for target " + TripleName, Context);
|
|
|
|
RangesSectionSize = 0;
|
|
LocSectionSize = 0;
|
|
LineSectionSize = 0;
|
|
FrameSectionSize = 0;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool DwarfStreamer::finish() {
|
|
MS->Finish();
|
|
return true;
|
|
}
|
|
|
|
/// \brief Set the current output section to debug_info and change
|
|
/// the MC Dwarf version to \p DwarfVersion.
|
|
void DwarfStreamer::switchToDebugInfoSection(unsigned DwarfVersion) {
|
|
MS->SwitchSection(MOFI->getDwarfInfoSection());
|
|
MC->setDwarfVersion(DwarfVersion);
|
|
}
|
|
|
|
/// \brief Emit the compilation unit header for \p Unit in the
|
|
/// debug_info section.
|
|
///
|
|
/// A Dwarf scetion header is encoded as:
|
|
/// uint32_t Unit length (omiting this field)
|
|
/// uint16_t Version
|
|
/// uint32_t Abbreviation table offset
|
|
/// uint8_t Address size
|
|
///
|
|
/// Leading to a total of 11 bytes.
|
|
void DwarfStreamer::emitCompileUnitHeader(CompileUnit &Unit) {
|
|
unsigned Version = Unit.getOrigUnit().getVersion();
|
|
switchToDebugInfoSection(Version);
|
|
|
|
// Emit size of content not including length itself. The size has
|
|
// already been computed in CompileUnit::computeOffsets(). Substract
|
|
// 4 to that size to account for the length field.
|
|
Asm->EmitInt32(Unit.getNextUnitOffset() - Unit.getStartOffset() - 4);
|
|
Asm->EmitInt16(Version);
|
|
// We share one abbreviations table across all units so it's always at the
|
|
// start of the section.
|
|
Asm->EmitInt32(0);
|
|
Asm->EmitInt8(Unit.getOrigUnit().getAddressByteSize());
|
|
}
|
|
|
|
/// \brief Emit the \p Abbrevs array as the shared abbreviation table
|
|
/// for the linked Dwarf file.
|
|
void DwarfStreamer::emitAbbrevs(const std::vector<DIEAbbrev *> &Abbrevs) {
|
|
MS->SwitchSection(MOFI->getDwarfAbbrevSection());
|
|
Asm->emitDwarfAbbrevs(Abbrevs);
|
|
}
|
|
|
|
/// \brief Recursively emit the DIE tree rooted at \p Die.
|
|
void DwarfStreamer::emitDIE(DIE &Die) {
|
|
MS->SwitchSection(MOFI->getDwarfInfoSection());
|
|
Asm->emitDwarfDIE(Die);
|
|
}
|
|
|
|
/// \brief Emit the debug_str section stored in \p Pool.
|
|
void DwarfStreamer::emitStrings(const NonRelocatableStringpool &Pool) {
|
|
Asm->OutStreamer->SwitchSection(MOFI->getDwarfStrSection());
|
|
for (auto *Entry = Pool.getFirstEntry(); Entry;
|
|
Entry = Pool.getNextEntry(Entry))
|
|
Asm->OutStreamer->EmitBytes(
|
|
StringRef(Entry->getKey().data(), Entry->getKey().size() + 1));
|
|
}
|
|
|
|
/// \brief Emit the debug_range section contents for \p FuncRange by
|
|
/// translating the original \p Entries. The debug_range section
|
|
/// format is totally trivial, consisting just of pairs of address
|
|
/// sized addresses describing the ranges.
|
|
void DwarfStreamer::emitRangesEntries(
|
|
int64_t UnitPcOffset, uint64_t OrigLowPc,
|
|
FunctionIntervals::const_iterator FuncRange,
|
|
const std::vector<DWARFDebugRangeList::RangeListEntry> &Entries,
|
|
unsigned AddressSize) {
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfRangesSection());
|
|
|
|
// Offset each range by the right amount.
|
|
int64_t PcOffset = FuncRange.value() + UnitPcOffset;
|
|
for (const auto &Range : Entries) {
|
|
if (Range.isBaseAddressSelectionEntry(AddressSize)) {
|
|
warn("unsupported base address selection operation",
|
|
"emitting debug_ranges");
|
|
break;
|
|
}
|
|
// Do not emit empty ranges.
|
|
if (Range.StartAddress == Range.EndAddress)
|
|
continue;
|
|
|
|
// All range entries should lie in the function range.
|
|
if (!(Range.StartAddress + OrigLowPc >= FuncRange.start() &&
|
|
Range.EndAddress + OrigLowPc <= FuncRange.stop()))
|
|
warn("inconsistent range data.", "emitting debug_ranges");
|
|
MS->EmitIntValue(Range.StartAddress + PcOffset, AddressSize);
|
|
MS->EmitIntValue(Range.EndAddress + PcOffset, AddressSize);
|
|
RangesSectionSize += 2 * AddressSize;
|
|
}
|
|
|
|
// Add the terminator entry.
|
|
MS->EmitIntValue(0, AddressSize);
|
|
MS->EmitIntValue(0, AddressSize);
|
|
RangesSectionSize += 2 * AddressSize;
|
|
}
|
|
|
|
/// \brief Emit the debug_aranges contribution of a unit and
|
|
/// if \p DoDebugRanges is true the debug_range contents for a
|
|
/// compile_unit level DW_AT_ranges attribute (Which are basically the
|
|
/// same thing with a different base address).
|
|
/// Just aggregate all the ranges gathered inside that unit.
|
|
void DwarfStreamer::emitUnitRangesEntries(CompileUnit &Unit,
|
|
bool DoDebugRanges) {
|
|
unsigned AddressSize = Unit.getOrigUnit().getAddressByteSize();
|
|
// Gather the ranges in a vector, so that we can simplify them. The
|
|
// IntervalMap will have coalesced the non-linked ranges, but here
|
|
// we want to coalesce the linked addresses.
|
|
std::vector<std::pair<uint64_t, uint64_t>> Ranges;
|
|
const auto &FunctionRanges = Unit.getFunctionRanges();
|
|
for (auto Range = FunctionRanges.begin(), End = FunctionRanges.end();
|
|
Range != End; ++Range)
|
|
Ranges.push_back(std::make_pair(Range.start() + Range.value(),
|
|
Range.stop() + Range.value()));
|
|
|
|
// The object addresses where sorted, but again, the linked
|
|
// addresses might end up in a different order.
|
|
std::sort(Ranges.begin(), Ranges.end());
|
|
|
|
if (!Ranges.empty()) {
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfARangesSection());
|
|
|
|
MCSymbol *BeginLabel = Asm->createTempSymbol("Barange");
|
|
MCSymbol *EndLabel = Asm->createTempSymbol("Earange");
|
|
|
|
unsigned HeaderSize =
|
|
sizeof(int32_t) + // Size of contents (w/o this field
|
|
sizeof(int16_t) + // DWARF ARange version number
|
|
sizeof(int32_t) + // Offset of CU in the .debug_info section
|
|
sizeof(int8_t) + // Pointer Size (in bytes)
|
|
sizeof(int8_t); // Segment Size (in bytes)
|
|
|
|
unsigned TupleSize = AddressSize * 2;
|
|
unsigned Padding = OffsetToAlignment(HeaderSize, TupleSize);
|
|
|
|
Asm->EmitLabelDifference(EndLabel, BeginLabel, 4); // Arange length
|
|
Asm->OutStreamer->EmitLabel(BeginLabel);
|
|
Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); // Version number
|
|
Asm->EmitInt32(Unit.getStartOffset()); // Corresponding unit's offset
|
|
Asm->EmitInt8(AddressSize); // Address size
|
|
Asm->EmitInt8(0); // Segment size
|
|
|
|
Asm->OutStreamer->EmitFill(Padding, 0x0);
|
|
|
|
for (auto Range = Ranges.begin(), End = Ranges.end(); Range != End;
|
|
++Range) {
|
|
uint64_t RangeStart = Range->first;
|
|
MS->EmitIntValue(RangeStart, AddressSize);
|
|
while ((Range + 1) != End && Range->second == (Range + 1)->first)
|
|
++Range;
|
|
MS->EmitIntValue(Range->second - RangeStart, AddressSize);
|
|
}
|
|
|
|
// Emit terminator
|
|
Asm->OutStreamer->EmitIntValue(0, AddressSize);
|
|
Asm->OutStreamer->EmitIntValue(0, AddressSize);
|
|
Asm->OutStreamer->EmitLabel(EndLabel);
|
|
}
|
|
|
|
if (!DoDebugRanges)
|
|
return;
|
|
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfRangesSection());
|
|
// Offset each range by the right amount.
|
|
int64_t PcOffset = -Unit.getLowPc();
|
|
// Emit coalesced ranges.
|
|
for (auto Range = Ranges.begin(), End = Ranges.end(); Range != End; ++Range) {
|
|
MS->EmitIntValue(Range->first + PcOffset, AddressSize);
|
|
while (Range + 1 != End && Range->second == (Range + 1)->first)
|
|
++Range;
|
|
MS->EmitIntValue(Range->second + PcOffset, AddressSize);
|
|
RangesSectionSize += 2 * AddressSize;
|
|
}
|
|
|
|
// Add the terminator entry.
|
|
MS->EmitIntValue(0, AddressSize);
|
|
MS->EmitIntValue(0, AddressSize);
|
|
RangesSectionSize += 2 * AddressSize;
|
|
}
|
|
|
|
/// \brief Emit location lists for \p Unit and update attribtues to
|
|
/// point to the new entries.
|
|
void DwarfStreamer::emitLocationsForUnit(const CompileUnit &Unit,
|
|
DWARFContext &Dwarf) {
|
|
const auto &Attributes = Unit.getLocationAttributes();
|
|
|
|
if (Attributes.empty())
|
|
return;
|
|
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfLocSection());
|
|
|
|
unsigned AddressSize = Unit.getOrigUnit().getAddressByteSize();
|
|
const DWARFSection &InputSec = Dwarf.getLocSection();
|
|
DataExtractor Data(InputSec.Data, Dwarf.isLittleEndian(), AddressSize);
|
|
DWARFUnit &OrigUnit = Unit.getOrigUnit();
|
|
const auto *OrigUnitDie = OrigUnit.getUnitDIE(false);
|
|
int64_t UnitPcOffset = 0;
|
|
uint64_t OrigLowPc = OrigUnitDie->getAttributeValueAsAddress(
|
|
&OrigUnit, dwarf::DW_AT_low_pc, -1ULL);
|
|
if (OrigLowPc != -1ULL)
|
|
UnitPcOffset = int64_t(OrigLowPc) - Unit.getLowPc();
|
|
|
|
for (const auto &Attr : Attributes) {
|
|
uint32_t Offset = Attr.first.get();
|
|
Attr.first.set(LocSectionSize);
|
|
// This is the quantity to add to the old location address to get
|
|
// the correct address for the new one.
|
|
int64_t LocPcOffset = Attr.second + UnitPcOffset;
|
|
while (Data.isValidOffset(Offset)) {
|
|
uint64_t Low = Data.getUnsigned(&Offset, AddressSize);
|
|
uint64_t High = Data.getUnsigned(&Offset, AddressSize);
|
|
LocSectionSize += 2 * AddressSize;
|
|
if (Low == 0 && High == 0) {
|
|
Asm->OutStreamer->EmitIntValue(0, AddressSize);
|
|
Asm->OutStreamer->EmitIntValue(0, AddressSize);
|
|
break;
|
|
}
|
|
Asm->OutStreamer->EmitIntValue(Low + LocPcOffset, AddressSize);
|
|
Asm->OutStreamer->EmitIntValue(High + LocPcOffset, AddressSize);
|
|
uint64_t Length = Data.getU16(&Offset);
|
|
Asm->OutStreamer->EmitIntValue(Length, 2);
|
|
// Just copy the bytes over.
|
|
Asm->OutStreamer->EmitBytes(
|
|
StringRef(InputSec.Data.substr(Offset, Length)));
|
|
Offset += Length;
|
|
LocSectionSize += Length + 2;
|
|
}
|
|
}
|
|
}
|
|
|
|
void DwarfStreamer::emitLineTableForUnit(StringRef PrologueBytes,
|
|
unsigned MinInstLength,
|
|
std::vector<DWARFDebugLine::Row> &Rows,
|
|
unsigned PointerSize) {
|
|
// Switch to the section where the table will be emitted into.
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfLineSection());
|
|
MCSymbol *LineStartSym = MC->createTempSymbol();
|
|
MCSymbol *LineEndSym = MC->createTempSymbol();
|
|
|
|
// The first 4 bytes is the total length of the information for this
|
|
// compilation unit (not including these 4 bytes for the length).
|
|
Asm->EmitLabelDifference(LineEndSym, LineStartSym, 4);
|
|
Asm->OutStreamer->EmitLabel(LineStartSym);
|
|
// Copy Prologue.
|
|
MS->EmitBytes(PrologueBytes);
|
|
LineSectionSize += PrologueBytes.size() + 4;
|
|
|
|
SmallString<128> EncodingBuffer;
|
|
raw_svector_ostream EncodingOS(EncodingBuffer);
|
|
|
|
if (Rows.empty()) {
|
|
// We only have the dummy entry, dsymutil emits an entry with a 0
|
|
// address in that case.
|
|
MCDwarfLineAddr::Encode(*MC, INT64_MAX, 0, EncodingOS);
|
|
MS->EmitBytes(EncodingOS.str());
|
|
LineSectionSize += EncodingBuffer.size();
|
|
MS->EmitLabel(LineEndSym);
|
|
return;
|
|
}
|
|
|
|
// Line table state machine fields
|
|
unsigned FileNum = 1;
|
|
unsigned LastLine = 1;
|
|
unsigned Column = 0;
|
|
unsigned IsStatement = 1;
|
|
unsigned Isa = 0;
|
|
uint64_t Address = -1ULL;
|
|
|
|
unsigned RowsSinceLastSequence = 0;
|
|
|
|
for (unsigned Idx = 0; Idx < Rows.size(); ++Idx) {
|
|
auto &Row = Rows[Idx];
|
|
|
|
int64_t AddressDelta;
|
|
if (Address == -1ULL) {
|
|
MS->EmitIntValue(dwarf::DW_LNS_extended_op, 1);
|
|
MS->EmitULEB128IntValue(PointerSize + 1);
|
|
MS->EmitIntValue(dwarf::DW_LNE_set_address, 1);
|
|
MS->EmitIntValue(Row.Address, PointerSize);
|
|
LineSectionSize += 2 + PointerSize + getULEB128Size(PointerSize + 1);
|
|
AddressDelta = 0;
|
|
} else {
|
|
AddressDelta = (Row.Address - Address) / MinInstLength;
|
|
}
|
|
|
|
// FIXME: code copied and transfromed from
|
|
// MCDwarf.cpp::EmitDwarfLineTable. We should find a way to share
|
|
// this code, but the current compatibility requirement with
|
|
// classic dsymutil makes it hard. Revisit that once this
|
|
// requirement is dropped.
|
|
|
|
if (FileNum != Row.File) {
|
|
FileNum = Row.File;
|
|
MS->EmitIntValue(dwarf::DW_LNS_set_file, 1);
|
|
MS->EmitULEB128IntValue(FileNum);
|
|
LineSectionSize += 1 + getULEB128Size(FileNum);
|
|
}
|
|
if (Column != Row.Column) {
|
|
Column = Row.Column;
|
|
MS->EmitIntValue(dwarf::DW_LNS_set_column, 1);
|
|
MS->EmitULEB128IntValue(Column);
|
|
LineSectionSize += 1 + getULEB128Size(Column);
|
|
}
|
|
|
|
// FIXME: We should handle the discriminator here, but dsymutil
|
|
// doesn' consider it, thus ignore it for now.
|
|
|
|
if (Isa != Row.Isa) {
|
|
Isa = Row.Isa;
|
|
MS->EmitIntValue(dwarf::DW_LNS_set_isa, 1);
|
|
MS->EmitULEB128IntValue(Isa);
|
|
LineSectionSize += 1 + getULEB128Size(Isa);
|
|
}
|
|
if (IsStatement != Row.IsStmt) {
|
|
IsStatement = Row.IsStmt;
|
|
MS->EmitIntValue(dwarf::DW_LNS_negate_stmt, 1);
|
|
LineSectionSize += 1;
|
|
}
|
|
if (Row.BasicBlock) {
|
|
MS->EmitIntValue(dwarf::DW_LNS_set_basic_block, 1);
|
|
LineSectionSize += 1;
|
|
}
|
|
|
|
if (Row.PrologueEnd) {
|
|
MS->EmitIntValue(dwarf::DW_LNS_set_prologue_end, 1);
|
|
LineSectionSize += 1;
|
|
}
|
|
|
|
if (Row.EpilogueBegin) {
|
|
MS->EmitIntValue(dwarf::DW_LNS_set_epilogue_begin, 1);
|
|
LineSectionSize += 1;
|
|
}
|
|
|
|
int64_t LineDelta = int64_t(Row.Line) - LastLine;
|
|
if (!Row.EndSequence) {
|
|
MCDwarfLineAddr::Encode(*MC, LineDelta, AddressDelta, EncodingOS);
|
|
MS->EmitBytes(EncodingOS.str());
|
|
LineSectionSize += EncodingBuffer.size();
|
|
EncodingBuffer.resize(0);
|
|
EncodingOS.resync();
|
|
Address = Row.Address;
|
|
LastLine = Row.Line;
|
|
RowsSinceLastSequence++;
|
|
} else {
|
|
if (LineDelta) {
|
|
MS->EmitIntValue(dwarf::DW_LNS_advance_line, 1);
|
|
MS->EmitSLEB128IntValue(LineDelta);
|
|
LineSectionSize += 1 + getSLEB128Size(LineDelta);
|
|
}
|
|
if (AddressDelta) {
|
|
MS->EmitIntValue(dwarf::DW_LNS_advance_pc, 1);
|
|
MS->EmitULEB128IntValue(AddressDelta);
|
|
LineSectionSize += 1 + getULEB128Size(AddressDelta);
|
|
}
|
|
MCDwarfLineAddr::Encode(*MC, INT64_MAX, 0, EncodingOS);
|
|
MS->EmitBytes(EncodingOS.str());
|
|
LineSectionSize += EncodingBuffer.size();
|
|
EncodingBuffer.resize(0);
|
|
EncodingOS.resync();
|
|
Address = -1ULL;
|
|
LastLine = FileNum = IsStatement = 1;
|
|
RowsSinceLastSequence = Column = Isa = 0;
|
|
}
|
|
}
|
|
|
|
if (RowsSinceLastSequence) {
|
|
MCDwarfLineAddr::Encode(*MC, INT64_MAX, 0, EncodingOS);
|
|
MS->EmitBytes(EncodingOS.str());
|
|
LineSectionSize += EncodingBuffer.size();
|
|
EncodingBuffer.resize(0);
|
|
EncodingOS.resync();
|
|
}
|
|
|
|
MS->EmitLabel(LineEndSym);
|
|
}
|
|
|
|
/// \brief Emit the pubnames or pubtypes section contribution for \p
|
|
/// Unit into \p Sec. The data is provided in \p Names.
|
|
void DwarfStreamer::emitPubSectionForUnit(
|
|
MCSection *Sec, StringRef SecName, const CompileUnit &Unit,
|
|
const std::vector<CompileUnit::AccelInfo> &Names) {
|
|
if (Names.empty())
|
|
return;
|
|
|
|
// Start the dwarf pubnames section.
|
|
Asm->OutStreamer->SwitchSection(Sec);
|
|
MCSymbol *BeginLabel = Asm->createTempSymbol("pub" + SecName + "_begin");
|
|
MCSymbol *EndLabel = Asm->createTempSymbol("pub" + SecName + "_end");
|
|
|
|
bool HeaderEmitted = false;
|
|
// Emit the pubnames for this compilation unit.
|
|
for (const auto &Name : Names) {
|
|
if (Name.SkipPubSection)
|
|
continue;
|
|
|
|
if (!HeaderEmitted) {
|
|
// Emit the header.
|
|
Asm->EmitLabelDifference(EndLabel, BeginLabel, 4); // Length
|
|
Asm->OutStreamer->EmitLabel(BeginLabel);
|
|
Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); // Version
|
|
Asm->EmitInt32(Unit.getStartOffset()); // Unit offset
|
|
Asm->EmitInt32(Unit.getNextUnitOffset() - Unit.getStartOffset()); // Size
|
|
HeaderEmitted = true;
|
|
}
|
|
Asm->EmitInt32(Name.Die->getOffset());
|
|
Asm->OutStreamer->EmitBytes(
|
|
StringRef(Name.Name.data(), Name.Name.size() + 1));
|
|
}
|
|
|
|
if (!HeaderEmitted)
|
|
return;
|
|
Asm->EmitInt32(0); // End marker.
|
|
Asm->OutStreamer->EmitLabel(EndLabel);
|
|
}
|
|
|
|
/// \brief Emit .debug_pubnames for \p Unit.
|
|
void DwarfStreamer::emitPubNamesForUnit(const CompileUnit &Unit) {
|
|
emitPubSectionForUnit(MC->getObjectFileInfo()->getDwarfPubNamesSection(),
|
|
"names", Unit, Unit.getPubnames());
|
|
}
|
|
|
|
/// \brief Emit .debug_pubtypes for \p Unit.
|
|
void DwarfStreamer::emitPubTypesForUnit(const CompileUnit &Unit) {
|
|
emitPubSectionForUnit(MC->getObjectFileInfo()->getDwarfPubTypesSection(),
|
|
"types", Unit, Unit.getPubtypes());
|
|
}
|
|
|
|
/// \brief Emit a CIE into the debug_frame section.
|
|
void DwarfStreamer::emitCIE(StringRef CIEBytes) {
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfFrameSection());
|
|
|
|
MS->EmitBytes(CIEBytes);
|
|
FrameSectionSize += CIEBytes.size();
|
|
}
|
|
|
|
/// \brief Emit a FDE into the debug_frame section. \p FDEBytes
|
|
/// contains the FDE data without the length, CIE offset and address
|
|
/// which will be replaced with the paramter values.
|
|
void DwarfStreamer::emitFDE(uint32_t CIEOffset, uint32_t AddrSize,
|
|
uint32_t Address, StringRef FDEBytes) {
|
|
MS->SwitchSection(MC->getObjectFileInfo()->getDwarfFrameSection());
|
|
|
|
MS->EmitIntValue(FDEBytes.size() + 4 + AddrSize, 4);
|
|
MS->EmitIntValue(CIEOffset, 4);
|
|
MS->EmitIntValue(Address, AddrSize);
|
|
MS->EmitBytes(FDEBytes);
|
|
FrameSectionSize += FDEBytes.size() + 8 + AddrSize;
|
|
}
|
|
|
|
/// \brief The core of the Dwarf linking logic.
|
|
///
|
|
/// The link of the dwarf information from the object files will be
|
|
/// driven by the selection of 'root DIEs', which are DIEs that
|
|
/// describe variables or functions that are present in the linked
|
|
/// binary (and thus have entries in the debug map). All the debug
|
|
/// information that will be linked (the DIEs, but also the line
|
|
/// tables, ranges, ...) is derived from that set of root DIEs.
|
|
///
|
|
/// The root DIEs are identified because they contain relocations that
|
|
/// correspond to a debug map entry at specific places (the low_pc for
|
|
/// a function, the location for a variable). These relocations are
|
|
/// called ValidRelocs in the DwarfLinker and are gathered as a very
|
|
/// first step when we start processing a DebugMapObject.
|
|
class DwarfLinker {
|
|
public:
|
|
DwarfLinker(StringRef OutputFilename, const LinkOptions &Options)
|
|
: OutputFilename(OutputFilename), Options(Options),
|
|
BinHolder(Options.Verbose), LastCIEOffset(0) {}
|
|
|
|
~DwarfLinker() {
|
|
for (auto *Abbrev : Abbreviations)
|
|
delete Abbrev;
|
|
}
|
|
|
|
/// \brief Link the contents of the DebugMap.
|
|
bool link(const DebugMap &);
|
|
|
|
private:
|
|
/// \brief Called at the start of a debug object link.
|
|
void startDebugObject(DWARFContext &, DebugMapObject &);
|
|
|
|
/// \brief Called at the end of a debug object link.
|
|
void endDebugObject();
|
|
|
|
/// \defgroup FindValidRelocations Translate debug map into a list
|
|
/// of relevant relocations
|
|
///
|
|
/// @{
|
|
struct ValidReloc {
|
|
uint32_t Offset;
|
|
uint32_t Size;
|
|
uint64_t Addend;
|
|
const DebugMapObject::DebugMapEntry *Mapping;
|
|
|
|
ValidReloc(uint32_t Offset, uint32_t Size, uint64_t Addend,
|
|
const DebugMapObject::DebugMapEntry *Mapping)
|
|
: Offset(Offset), Size(Size), Addend(Addend), Mapping(Mapping) {}
|
|
|
|
bool operator<(const ValidReloc &RHS) const { return Offset < RHS.Offset; }
|
|
};
|
|
|
|
/// \brief The valid relocations for the current DebugMapObject.
|
|
/// This vector is sorted by relocation offset.
|
|
std::vector<ValidReloc> ValidRelocs;
|
|
|
|
/// \brief Index into ValidRelocs of the next relocation to
|
|
/// consider. As we walk the DIEs in acsending file offset and as
|
|
/// ValidRelocs is sorted by file offset, keeping this index
|
|
/// uptodate is all we have to do to have a cheap lookup during the
|
|
/// root DIE selection and during DIE cloning.
|
|
unsigned NextValidReloc;
|
|
|
|
bool findValidRelocsInDebugInfo(const object::ObjectFile &Obj,
|
|
const DebugMapObject &DMO);
|
|
|
|
bool findValidRelocs(const object::SectionRef &Section,
|
|
const object::ObjectFile &Obj,
|
|
const DebugMapObject &DMO);
|
|
|
|
void findValidRelocsMachO(const object::SectionRef &Section,
|
|
const object::MachOObjectFile &Obj,
|
|
const DebugMapObject &DMO);
|
|
/// @}
|
|
|
|
/// \defgroup FindRootDIEs Find DIEs corresponding to debug map entries.
|
|
///
|
|
/// @{
|
|
/// \brief Recursively walk the \p DIE tree and look for DIEs to
|
|
/// keep. Store that information in \p CU's DIEInfo.
|
|
void lookForDIEsToKeep(const DWARFDebugInfoEntryMinimal &DIE,
|
|
const DebugMapObject &DMO, CompileUnit &CU,
|
|
unsigned Flags);
|
|
|
|
/// \brief Flags passed to DwarfLinker::lookForDIEsToKeep
|
|
enum TravesalFlags {
|
|
TF_Keep = 1 << 0, ///< Mark the traversed DIEs as kept.
|
|
TF_InFunctionScope = 1 << 1, ///< Current scope is a fucntion scope.
|
|
TF_DependencyWalk = 1 << 2, ///< Walking the dependencies of a kept DIE.
|
|
TF_ParentWalk = 1 << 3, ///< Walking up the parents of a kept DIE.
|
|
TF_ODR = 1 << 4, ///< Use the ODR whhile keeping dependants.
|
|
};
|
|
|
|
/// \brief Mark the passed DIE as well as all the ones it depends on
|
|
/// as kept.
|
|
void keepDIEAndDenpendencies(const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit::DIEInfo &MyInfo,
|
|
const DebugMapObject &DMO, CompileUnit &CU,
|
|
bool UseODR);
|
|
|
|
unsigned shouldKeepDIE(const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
|
|
unsigned Flags);
|
|
|
|
unsigned shouldKeepVariableDIE(const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit &Unit,
|
|
CompileUnit::DIEInfo &MyInfo, unsigned Flags);
|
|
|
|
unsigned shouldKeepSubprogramDIE(const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit &Unit,
|
|
CompileUnit::DIEInfo &MyInfo,
|
|
unsigned Flags);
|
|
|
|
bool hasValidRelocation(uint32_t StartOffset, uint32_t EndOffset,
|
|
CompileUnit::DIEInfo &Info);
|
|
/// @}
|
|
|
|
/// \defgroup Linking Methods used to link the debug information
|
|
///
|
|
/// @{
|
|
/// \brief Recursively clone \p InputDIE into an tree of DIE objects
|
|
/// where useless (as decided by lookForDIEsToKeep()) bits have been
|
|
/// stripped out and addresses have been rewritten according to the
|
|
/// debug map.
|
|
///
|
|
/// \param OutOffset is the offset the cloned DIE in the output
|
|
/// compile unit.
|
|
/// \param PCOffset (while cloning a function scope) is the offset
|
|
/// applied to the entry point of the function to get the linked address.
|
|
///
|
|
/// \returns the root of the cloned tree.
|
|
DIE *cloneDIE(const DWARFDebugInfoEntryMinimal &InputDIE, CompileUnit &U,
|
|
int64_t PCOffset, uint32_t OutOffset);
|
|
|
|
typedef DWARFAbbreviationDeclaration::AttributeSpec AttributeSpec;
|
|
|
|
/// \brief Information gathered and exchanged between the various
|
|
/// clone*Attributes helpers about the attributes of a particular DIE.
|
|
struct AttributesInfo {
|
|
const char *Name, *MangledName; ///< Names.
|
|
uint32_t NameOffset, MangledNameOffset; ///< Offsets in the string pool.
|
|
|
|
uint64_t OrigHighPc; ///< Value of AT_high_pc in the input DIE
|
|
int64_t PCOffset; ///< Offset to apply to PC addresses inside a function.
|
|
|
|
bool HasLowPc; ///< Does the DIE have a low_pc attribute?
|
|
bool IsDeclaration; ///< Is this DIE only a declaration?
|
|
|
|
AttributesInfo()
|
|
: Name(nullptr), MangledName(nullptr), NameOffset(0),
|
|
MangledNameOffset(0), OrigHighPc(0), PCOffset(0), HasLowPc(false),
|
|
IsDeclaration(false) {}
|
|
};
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
unsigned cloneAttribute(DIE &Die, const DWARFDebugInfoEntryMinimal &InputDIE,
|
|
CompileUnit &U, const DWARFFormValue &Val,
|
|
const AttributeSpec AttrSpec, unsigned AttrSize,
|
|
AttributesInfo &AttrInfo);
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
unsigned cloneStringAttribute(DIE &Die, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val, const DWARFUnit &U);
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
unsigned
|
|
cloneDieReferenceAttribute(DIE &Die,
|
|
const DWARFDebugInfoEntryMinimal &InputDIE,
|
|
AttributeSpec AttrSpec, unsigned AttrSize,
|
|
const DWARFFormValue &Val, CompileUnit &Unit);
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
unsigned cloneBlockAttribute(DIE &Die, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val, unsigned AttrSize);
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
unsigned cloneAddressAttribute(DIE &Die, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val,
|
|
const CompileUnit &Unit, AttributesInfo &Info);
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
unsigned cloneScalarAttribute(DIE &Die,
|
|
const DWARFDebugInfoEntryMinimal &InputDIE,
|
|
CompileUnit &U, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val, unsigned AttrSize,
|
|
AttributesInfo &Info);
|
|
|
|
/// \brief Helper for cloneDIE.
|
|
bool applyValidRelocs(MutableArrayRef<char> Data, uint32_t BaseOffset,
|
|
bool isLittleEndian);
|
|
|
|
/// \brief Assign an abbreviation number to \p Abbrev
|
|
void AssignAbbrev(DIEAbbrev &Abbrev);
|
|
|
|
/// \brief FoldingSet that uniques the abbreviations.
|
|
FoldingSet<DIEAbbrev> AbbreviationsSet;
|
|
/// \brief Storage for the unique Abbreviations.
|
|
/// This is passed to AsmPrinter::emitDwarfAbbrevs(), thus it cannot
|
|
/// be changed to a vecot of unique_ptrs.
|
|
std::vector<DIEAbbrev *> Abbreviations;
|
|
|
|
/// \brief Compute and emit debug_ranges section for \p Unit, and
|
|
/// patch the attributes referencing it.
|
|
void patchRangesForUnit(const CompileUnit &Unit, DWARFContext &Dwarf) const;
|
|
|
|
/// \brief Generate and emit the DW_AT_ranges attribute for a
|
|
/// compile_unit if it had one.
|
|
void generateUnitRanges(CompileUnit &Unit) const;
|
|
|
|
/// \brief Extract the line tables fromt he original dwarf, extract
|
|
/// the relevant parts according to the linked function ranges and
|
|
/// emit the result in the debug_line section.
|
|
void patchLineTableForUnit(CompileUnit &Unit, DWARFContext &OrigDwarf);
|
|
|
|
/// \brief Emit the accelerator entries for \p Unit.
|
|
void emitAcceleratorEntriesForUnit(CompileUnit &Unit);
|
|
|
|
/// \brief Patch the frame info for an object file and emit it.
|
|
void patchFrameInfoForObject(const DebugMapObject &, DWARFContext &,
|
|
unsigned AddressSize);
|
|
|
|
/// \brief DIELoc objects that need to be destructed (but not freed!).
|
|
std::vector<DIELoc *> DIELocs;
|
|
/// \brief DIEBlock objects that need to be destructed (but not freed!).
|
|
std::vector<DIEBlock *> DIEBlocks;
|
|
/// \brief Allocator used for all the DIEValue objects.
|
|
BumpPtrAllocator DIEAlloc;
|
|
/// @}
|
|
|
|
/// ODR Contexts for that link.
|
|
DeclContextTree ODRContexts;
|
|
|
|
/// \defgroup Helpers Various helper methods.
|
|
///
|
|
/// @{
|
|
const DWARFDebugInfoEntryMinimal *
|
|
resolveDIEReference(const DWARFFormValue &RefValue, const DWARFUnit &Unit,
|
|
const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit *&ReferencedCU);
|
|
|
|
CompileUnit *getUnitForOffset(unsigned Offset);
|
|
|
|
bool getDIENames(const DWARFDebugInfoEntryMinimal &Die, DWARFUnit &U,
|
|
AttributesInfo &Info);
|
|
|
|
void reportWarning(const Twine &Warning, const DWARFUnit *Unit = nullptr,
|
|
const DWARFDebugInfoEntryMinimal *DIE = nullptr) const;
|
|
|
|
bool createStreamer(Triple TheTriple, StringRef OutputFilename);
|
|
|
|
/// \brief Attempt to load a debug object from disk.
|
|
ErrorOr<const object::ObjectFile &> loadObject(BinaryHolder &BinaryHolder,
|
|
DebugMapObject &Obj,
|
|
const DebugMap &Map);
|
|
/// @}
|
|
|
|
private:
|
|
std::string OutputFilename;
|
|
LinkOptions Options;
|
|
BinaryHolder BinHolder;
|
|
std::unique_ptr<DwarfStreamer> Streamer;
|
|
|
|
/// The units of the current debug map object.
|
|
std::vector<CompileUnit> Units;
|
|
|
|
/// The debug map object curently under consideration.
|
|
DebugMapObject *CurrentDebugObject;
|
|
|
|
/// \brief The Dwarf string pool
|
|
NonRelocatableStringpool StringPool;
|
|
|
|
/// \brief This map is keyed by the entry PC of functions in that
|
|
/// debug object and the associated value is a pair storing the
|
|
/// corresponding end PC and the offset to apply to get the linked
|
|
/// address.
|
|
///
|
|
/// See startDebugObject() for a more complete description of its use.
|
|
std::map<uint64_t, std::pair<uint64_t, int64_t>> Ranges;
|
|
|
|
/// \brief The CIEs that have been emitted in the output
|
|
/// section. The actual CIE data serves a the key to this StringMap,
|
|
/// this takes care of comparing the semantics of CIEs defined in
|
|
/// different object files.
|
|
StringMap<uint32_t> EmittedCIEs;
|
|
|
|
/// Offset of the last CIE that has been emitted in the output
|
|
/// debug_frame section.
|
|
uint32_t LastCIEOffset;
|
|
};
|
|
|
|
/// \brief Similar to DWARFUnitSection::getUnitForOffset(), but
|
|
/// returning our CompileUnit object instead.
|
|
CompileUnit *DwarfLinker::getUnitForOffset(unsigned Offset) {
|
|
auto CU =
|
|
std::upper_bound(Units.begin(), Units.end(), Offset,
|
|
[](uint32_t LHS, const CompileUnit &RHS) {
|
|
return LHS < RHS.getOrigUnit().getNextUnitOffset();
|
|
});
|
|
return CU != Units.end() ? &*CU : nullptr;
|
|
}
|
|
|
|
/// \brief Resolve the DIE attribute reference that has been
|
|
/// extracted in \p RefValue. The resulting DIE migh be in another
|
|
/// CompileUnit which is stored into \p ReferencedCU.
|
|
/// \returns null if resolving fails for any reason.
|
|
const DWARFDebugInfoEntryMinimal *DwarfLinker::resolveDIEReference(
|
|
const DWARFFormValue &RefValue, const DWARFUnit &Unit,
|
|
const DWARFDebugInfoEntryMinimal &DIE, CompileUnit *&RefCU) {
|
|
assert(RefValue.isFormClass(DWARFFormValue::FC_Reference));
|
|
uint64_t RefOffset = *RefValue.getAsReference(&Unit);
|
|
|
|
if ((RefCU = getUnitForOffset(RefOffset)))
|
|
if (const auto *RefDie = RefCU->getOrigUnit().getDIEForOffset(RefOffset))
|
|
return RefDie;
|
|
|
|
reportWarning("could not find referenced DIE", &Unit, &DIE);
|
|
return nullptr;
|
|
}
|
|
|
|
/// \returns whether the passed \a Attr type might contain a DIE
|
|
/// reference suitable for ODR uniquing.
|
|
static bool isODRAttribute(uint16_t Attr) {
|
|
switch (Attr) {
|
|
default:
|
|
return false;
|
|
case dwarf::DW_AT_type:
|
|
case dwarf::DW_AT_containing_type:
|
|
case dwarf::DW_AT_specification:
|
|
case dwarf::DW_AT_abstract_origin:
|
|
case dwarf::DW_AT_import:
|
|
return true;
|
|
}
|
|
llvm_unreachable("Improper attribute.");
|
|
}
|
|
|
|
/// Set the last DIE/CU a context was seen in and, possibly invalidate
|
|
/// the context if it is ambiguous.
|
|
///
|
|
/// In the current implementation, we don't handle overloaded
|
|
/// functions well, because the argument types are not taken into
|
|
/// account when computing the DeclContext tree.
|
|
///
|
|
/// Some of this is mitigated byt using mangled names that do contain
|
|
/// the arguments types, but sometimes (eg. with function templates)
|
|
/// we don't have that. In that case, just do not unique anything that
|
|
/// refers to the contexts we are not able to distinguish.
|
|
///
|
|
/// If a context that is not a namespace appears twice in the same CU,
|
|
/// we know it is ambiguous. Make it invalid.
|
|
bool DeclContext::setLastSeenDIE(CompileUnit &U,
|
|
const DWARFDebugInfoEntryMinimal *Die) {
|
|
if (LastSeenCompileUnitID == U.getUniqueID()) {
|
|
DWARFUnit &OrigUnit = U.getOrigUnit();
|
|
uint32_t FirstIdx = OrigUnit.getDIEIndex(LastSeenDIE);
|
|
U.getInfo(FirstIdx).Ctxt = nullptr;
|
|
return false;
|
|
}
|
|
|
|
LastSeenCompileUnitID = U.getUniqueID();
|
|
LastSeenDIE = Die;
|
|
return true;
|
|
}
|
|
|
|
/// Get the child context of \a Context corresponding to \a DIE.
|
|
///
|
|
/// \returns the child context or null if we shouldn't track children
|
|
/// contexts. It also returns an additional bit meaning 'invalid'. An
|
|
/// invalid context means it shouldn't be considered for uniquing, but
|
|
/// its not returning null, because some children of that context
|
|
/// might be uniquing candidates.
|
|
/// FIXME: this is for dsymutil-classic compatibility, I don't think
|
|
/// it buys us much.
|
|
PointerIntPair<DeclContext *, 1> DeclContextTree::getChildDeclContext(
|
|
DeclContext &Context, const DWARFDebugInfoEntryMinimal *DIE, CompileUnit &U,
|
|
NonRelocatableStringpool &StringPool) {
|
|
unsigned Tag = DIE->getTag();
|
|
|
|
// FIXME: dsymutil-classic compat: We should bail out here if we
|
|
// have a specification or an abstract_origin. We will get the
|
|
// parent context wrong here.
|
|
|
|
switch (Tag) {
|
|
default:
|
|
// By default stop gathering child contexts.
|
|
return PointerIntPair<DeclContext *, 1>(nullptr);
|
|
case dwarf::DW_TAG_compile_unit:
|
|
// FIXME: Add support for DW_TAG_module.
|
|
return PointerIntPair<DeclContext *, 1>(&Context);
|
|
case dwarf::DW_TAG_subprogram:
|
|
// Do not unique anything inside CU local functions.
|
|
if ((Context.getTag() == dwarf::DW_TAG_namespace ||
|
|
Context.getTag() == dwarf::DW_TAG_compile_unit) &&
|
|
!DIE->getAttributeValueAsUnsignedConstant(&U.getOrigUnit(),
|
|
dwarf::DW_AT_external, 0))
|
|
return PointerIntPair<DeclContext *, 1>(nullptr);
|
|
// Fallthrough
|
|
case dwarf::DW_TAG_member:
|
|
case dwarf::DW_TAG_namespace:
|
|
case dwarf::DW_TAG_structure_type:
|
|
case dwarf::DW_TAG_class_type:
|
|
case dwarf::DW_TAG_union_type:
|
|
case dwarf::DW_TAG_enumeration_type:
|
|
case dwarf::DW_TAG_typedef:
|
|
// Artificial things might be ambiguous, because they might be
|
|
// created on demand. For example implicitely defined constructors
|
|
// are ambiguous because of the way we identify contexts, and they
|
|
// won't be generated everytime everywhere.
|
|
if (DIE->getAttributeValueAsUnsignedConstant(&U.getOrigUnit(),
|
|
dwarf::DW_AT_artificial, 0))
|
|
return PointerIntPair<DeclContext *, 1>(nullptr);
|
|
break;
|
|
}
|
|
|
|
const char *Name = DIE->getName(&U.getOrigUnit(), DINameKind::LinkageName);
|
|
const char *ShortName = DIE->getName(&U.getOrigUnit(), DINameKind::ShortName);
|
|
StringRef NameRef;
|
|
StringRef ShortNameRef;
|
|
StringRef FileRef;
|
|
|
|
if (Name)
|
|
NameRef = StringPool.internString(Name);
|
|
else if (Tag == dwarf::DW_TAG_namespace)
|
|
// FIXME: For dsymutil-classic compatibility. I think uniquing
|
|
// within anonymous namespaces is wrong. There is no ODR guarantee
|
|
// there.
|
|
NameRef = StringPool.internString("(anonymous namespace)");
|
|
|
|
if (ShortName && ShortName != Name)
|
|
ShortNameRef = StringPool.internString(ShortName);
|
|
else
|
|
ShortNameRef = NameRef;
|
|
|
|
if (Tag != dwarf::DW_TAG_class_type && Tag != dwarf::DW_TAG_structure_type &&
|
|
Tag != dwarf::DW_TAG_union_type &&
|
|
Tag != dwarf::DW_TAG_enumeration_type && NameRef.empty())
|
|
return PointerIntPair<DeclContext *, 1>(nullptr);
|
|
|
|
std::string File;
|
|
unsigned Line = 0;
|
|
unsigned ByteSize = 0;
|
|
|
|
// Gather some discriminating data about the DeclContext we will be
|
|
// creating: File, line number and byte size. This shouldn't be
|
|
// necessary, because the ODR is just about names, but given that we
|
|
// do some approximations with overloaded functions and anonymous
|
|
// namespaces, use these additional data points to make the process safer.
|
|
ByteSize = DIE->getAttributeValueAsUnsignedConstant(
|
|
&U.getOrigUnit(), dwarf::DW_AT_byte_size, UINT64_MAX);
|
|
if (Tag != dwarf::DW_TAG_namespace || !Name) {
|
|
if (unsigned FileNum = DIE->getAttributeValueAsUnsignedConstant(
|
|
&U.getOrigUnit(), dwarf::DW_AT_decl_file, 0)) {
|
|
if (const auto *LT = U.getOrigUnit().getContext().getLineTableForUnit(
|
|
&U.getOrigUnit())) {
|
|
// FIXME: dsymutil-classic compatibility. I'd rather not
|
|
// unique anything in anonymous namespaces, but if we do, then
|
|
// verify that the file and line correspond.
|
|
if (!Name && Tag == dwarf::DW_TAG_namespace)
|
|
FileNum = 1;
|
|
|
|
// FIXME: Passing U.getOrigUnit().getCompilationDir()
|
|
// instead of "" would allow more uniquing, but for now, do
|
|
// it this way to match dsymutil-classic.
|
|
if (LT->getFileNameByIndex(
|
|
FileNum, "",
|
|
DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath,
|
|
File)) {
|
|
Line = DIE->getAttributeValueAsUnsignedConstant(
|
|
&U.getOrigUnit(), dwarf::DW_AT_decl_line, 0);
|
|
#ifdef HAVE_REALPATH
|
|
// Cache the resolved paths, because calling realpath is expansive.
|
|
if (const char *ResolvedPath = U.getResolvedPath(FileNum)) {
|
|
File = ResolvedPath;
|
|
} else {
|
|
char RealPath[PATH_MAX + 1];
|
|
RealPath[PATH_MAX] = 0;
|
|
if (::realpath(File.c_str(), RealPath))
|
|
File = RealPath;
|
|
U.setResolvedPath(FileNum, File);
|
|
}
|
|
#endif
|
|
FileRef = StringPool.internString(File);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!Line && NameRef.empty())
|
|
return PointerIntPair<DeclContext *, 1>(nullptr);
|
|
|
|
// FIXME: dsymutil-classic compat won't unique the same type
|
|
// presented once as a struct and once as a class. Use the Tag in
|
|
// the fully qualified name hash to get the same effect.
|
|
// We hash NameRef, which is the mangled name, in order to get most
|
|
// overloaded functions resolvec correctly.
|
|
unsigned Hash = hash_combine(Context.getQualifiedNameHash(), Tag, NameRef);
|
|
|
|
// FIXME: dsymutil-classic compatibility: when we don't have a name,
|
|
// use the filename.
|
|
if (Tag == dwarf::DW_TAG_namespace && NameRef == "(anonymous namespace)")
|
|
Hash = hash_combine(Hash, FileRef);
|
|
|
|
// Now look if this context already exists.
|
|
DeclContext Key(Hash, Line, ByteSize, Tag, NameRef, FileRef, Context);
|
|
auto ContextIter = Contexts.find(&Key);
|
|
|
|
if (ContextIter == Contexts.end()) {
|
|
// The context wasn't found.
|
|
bool Inserted;
|
|
DeclContext *NewContext =
|
|
new (Allocator) DeclContext(Hash, Line, ByteSize, Tag, NameRef, FileRef,
|
|
Context, DIE, U.getUniqueID());
|
|
std::tie(ContextIter, Inserted) = Contexts.insert(NewContext);
|
|
assert(Inserted && "Failed to insert DeclContext");
|
|
(void)Inserted;
|
|
} else if (Tag != dwarf::DW_TAG_namespace &&
|
|
!(*ContextIter)->setLastSeenDIE(U, DIE)) {
|
|
// The context was found, but it is ambiguous with another context
|
|
// in the same file. Mark it invalid.
|
|
return PointerIntPair<DeclContext *, 1>(*ContextIter, /* Invalid= */ 1);
|
|
}
|
|
|
|
assert(ContextIter != Contexts.end());
|
|
// FIXME: dsymutil-classic compatibility. Union types aren't
|
|
// uniques, but their children might be.
|
|
if ((Tag == dwarf::DW_TAG_subprogram &&
|
|
Context.getTag() != dwarf::DW_TAG_structure_type &&
|
|
Context.getTag() != dwarf::DW_TAG_class_type) ||
|
|
(Tag == dwarf::DW_TAG_union_type))
|
|
return PointerIntPair<DeclContext *, 1>(*ContextIter, /* Invalid= */ 1);
|
|
|
|
return PointerIntPair<DeclContext *, 1>(*ContextIter);
|
|
}
|
|
|
|
/// \brief Get the potential name and mangled name for the entity
|
|
/// described by \p Die and store them in \Info if they are not
|
|
/// already there.
|
|
/// \returns is a name was found.
|
|
bool DwarfLinker::getDIENames(const DWARFDebugInfoEntryMinimal &Die,
|
|
DWARFUnit &U, AttributesInfo &Info) {
|
|
// FIXME: a bit wastefull as the first getName might return the
|
|
// short name.
|
|
if (!Info.MangledName &&
|
|
(Info.MangledName = Die.getName(&U, DINameKind::LinkageName)))
|
|
Info.MangledNameOffset = StringPool.getStringOffset(Info.MangledName);
|
|
|
|
if (!Info.Name && (Info.Name = Die.getName(&U, DINameKind::ShortName)))
|
|
Info.NameOffset = StringPool.getStringOffset(Info.Name);
|
|
|
|
return Info.Name || Info.MangledName;
|
|
}
|
|
|
|
/// \brief Report a warning to the user, optionaly including
|
|
/// information about a specific \p DIE related to the warning.
|
|
void DwarfLinker::reportWarning(const Twine &Warning, const DWARFUnit *Unit,
|
|
const DWARFDebugInfoEntryMinimal *DIE) const {
|
|
StringRef Context = "<debug map>";
|
|
if (CurrentDebugObject)
|
|
Context = CurrentDebugObject->getObjectFilename();
|
|
warn(Warning, Context);
|
|
|
|
if (!Options.Verbose || !DIE)
|
|
return;
|
|
|
|
errs() << " in DIE:\n";
|
|
DIE->dump(errs(), const_cast<DWARFUnit *>(Unit), 0 /* RecurseDepth */,
|
|
6 /* Indent */);
|
|
}
|
|
|
|
bool DwarfLinker::createStreamer(Triple TheTriple, StringRef OutputFilename) {
|
|
if (Options.NoOutput)
|
|
return true;
|
|
|
|
Streamer = llvm::make_unique<DwarfStreamer>();
|
|
return Streamer->init(TheTriple, OutputFilename);
|
|
}
|
|
|
|
/// \brief Recursive helper to gather the child->parent relationships in the
|
|
/// original compile unit.
|
|
static void gatherDIEParents(const DWARFDebugInfoEntryMinimal *DIE,
|
|
unsigned ParentIdx, CompileUnit &CU,
|
|
DeclContext *CurrentDeclContext,
|
|
NonRelocatableStringpool &StringPool,
|
|
DeclContextTree &Contexts) {
|
|
unsigned MyIdx = CU.getOrigUnit().getDIEIndex(DIE);
|
|
CompileUnit::DIEInfo &Info = CU.getInfo(MyIdx);
|
|
|
|
Info.ParentIdx = ParentIdx;
|
|
if (CU.hasODR()) {
|
|
if (CurrentDeclContext) {
|
|
auto PtrInvalidPair = Contexts.getChildDeclContext(*CurrentDeclContext,
|
|
DIE, CU, StringPool);
|
|
CurrentDeclContext = PtrInvalidPair.getPointer();
|
|
Info.Ctxt =
|
|
PtrInvalidPair.getInt() ? nullptr : PtrInvalidPair.getPointer();
|
|
} else
|
|
Info.Ctxt = CurrentDeclContext = nullptr;
|
|
}
|
|
|
|
if (DIE->hasChildren())
|
|
for (auto *Child = DIE->getFirstChild(); Child && !Child->isNULL();
|
|
Child = Child->getSibling())
|
|
gatherDIEParents(Child, MyIdx, CU, CurrentDeclContext, StringPool,
|
|
Contexts);
|
|
}
|
|
|
|
static bool dieNeedsChildrenToBeMeaningful(uint32_t Tag) {
|
|
switch (Tag) {
|
|
default:
|
|
return false;
|
|
case dwarf::DW_TAG_subprogram:
|
|
case dwarf::DW_TAG_lexical_block:
|
|
case dwarf::DW_TAG_subroutine_type:
|
|
case dwarf::DW_TAG_structure_type:
|
|
case dwarf::DW_TAG_class_type:
|
|
case dwarf::DW_TAG_union_type:
|
|
return true;
|
|
}
|
|
llvm_unreachable("Invalid Tag");
|
|
}
|
|
|
|
static unsigned getRefAddrSize(const DWARFUnit &U) {
|
|
if (U.getVersion() == 2)
|
|
return U.getAddressByteSize();
|
|
return 4;
|
|
}
|
|
|
|
void DwarfLinker::startDebugObject(DWARFContext &Dwarf, DebugMapObject &Obj) {
|
|
Units.reserve(Dwarf.getNumCompileUnits());
|
|
NextValidReloc = 0;
|
|
// Iterate over the debug map entries and put all the ones that are
|
|
// functions (because they have a size) into the Ranges map. This
|
|
// map is very similar to the FunctionRanges that are stored in each
|
|
// unit, with 2 notable differences:
|
|
// - obviously this one is global, while the other ones are per-unit.
|
|
// - this one contains not only the functions described in the DIE
|
|
// tree, but also the ones that are only in the debug map.
|
|
// The latter information is required to reproduce dsymutil's logic
|
|
// while linking line tables. The cases where this information
|
|
// matters look like bugs that need to be investigated, but for now
|
|
// we need to reproduce dsymutil's behavior.
|
|
// FIXME: Once we understood exactly if that information is needed,
|
|
// maybe totally remove this (or try to use it to do a real
|
|
// -gline-tables-only on Darwin.
|
|
for (const auto &Entry : Obj.symbols()) {
|
|
const auto &Mapping = Entry.getValue();
|
|
if (Mapping.Size)
|
|
Ranges[Mapping.ObjectAddress] = std::make_pair(
|
|
Mapping.ObjectAddress + Mapping.Size,
|
|
int64_t(Mapping.BinaryAddress) - Mapping.ObjectAddress);
|
|
}
|
|
}
|
|
|
|
void DwarfLinker::endDebugObject() {
|
|
Units.clear();
|
|
ValidRelocs.clear();
|
|
Ranges.clear();
|
|
|
|
for (auto I = DIEBlocks.begin(), E = DIEBlocks.end(); I != E; ++I)
|
|
(*I)->~DIEBlock();
|
|
for (auto I = DIELocs.begin(), E = DIELocs.end(); I != E; ++I)
|
|
(*I)->~DIELoc();
|
|
|
|
DIEBlocks.clear();
|
|
DIELocs.clear();
|
|
DIEAlloc.Reset();
|
|
}
|
|
|
|
/// \brief Iterate over the relocations of the given \p Section and
|
|
/// store the ones that correspond to debug map entries into the
|
|
/// ValidRelocs array.
|
|
void DwarfLinker::findValidRelocsMachO(const object::SectionRef &Section,
|
|
const object::MachOObjectFile &Obj,
|
|
const DebugMapObject &DMO) {
|
|
StringRef Contents;
|
|
Section.getContents(Contents);
|
|
DataExtractor Data(Contents, Obj.isLittleEndian(), 0);
|
|
|
|
for (const object::RelocationRef &Reloc : Section.relocations()) {
|
|
object::DataRefImpl RelocDataRef = Reloc.getRawDataRefImpl();
|
|
MachO::any_relocation_info MachOReloc = Obj.getRelocation(RelocDataRef);
|
|
unsigned RelocSize = 1 << Obj.getAnyRelocationLength(MachOReloc);
|
|
uint64_t Offset64 = Reloc.getOffset();
|
|
if ((RelocSize != 4 && RelocSize != 8)) {
|
|
reportWarning(" unsupported relocation in debug_info section.");
|
|
continue;
|
|
}
|
|
uint32_t Offset = Offset64;
|
|
// Mach-o uses REL relocations, the addend is at the relocation offset.
|
|
uint64_t Addend = Data.getUnsigned(&Offset, RelocSize);
|
|
|
|
auto Sym = Reloc.getSymbol();
|
|
if (Sym != Obj.symbol_end()) {
|
|
ErrorOr<StringRef> SymbolName = Sym->getName();
|
|
if (!SymbolName) {
|
|
reportWarning("error getting relocation symbol name.");
|
|
continue;
|
|
}
|
|
if (const auto *Mapping = DMO.lookupSymbol(*SymbolName))
|
|
ValidRelocs.emplace_back(Offset64, RelocSize, Addend, Mapping);
|
|
} else if (const auto *Mapping = DMO.lookupObjectAddress(Addend)) {
|
|
// Do not store the addend. The addend was the address of the
|
|
// symbol in the object file, the address in the binary that is
|
|
// stored in the debug map doesn't need to be offseted.
|
|
ValidRelocs.emplace_back(Offset64, RelocSize, 0, Mapping);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// \brief Dispatch the valid relocation finding logic to the
|
|
/// appropriate handler depending on the object file format.
|
|
bool DwarfLinker::findValidRelocs(const object::SectionRef &Section,
|
|
const object::ObjectFile &Obj,
|
|
const DebugMapObject &DMO) {
|
|
// Dispatch to the right handler depending on the file type.
|
|
if (auto *MachOObj = dyn_cast<object::MachOObjectFile>(&Obj))
|
|
findValidRelocsMachO(Section, *MachOObj, DMO);
|
|
else
|
|
reportWarning(Twine("unsupported object file type: ") + Obj.getFileName());
|
|
|
|
if (ValidRelocs.empty())
|
|
return false;
|
|
|
|
// Sort the relocations by offset. We will walk the DIEs linearly in
|
|
// the file, this allows us to just keep an index in the relocation
|
|
// array that we advance during our walk, rather than resorting to
|
|
// some associative container. See DwarfLinker::NextValidReloc.
|
|
std::sort(ValidRelocs.begin(), ValidRelocs.end());
|
|
return true;
|
|
}
|
|
|
|
/// \brief Look for relocations in the debug_info section that match
|
|
/// entries in the debug map. These relocations will drive the Dwarf
|
|
/// link by indicating which DIEs refer to symbols present in the
|
|
/// linked binary.
|
|
/// \returns wether there are any valid relocations in the debug info.
|
|
bool DwarfLinker::findValidRelocsInDebugInfo(const object::ObjectFile &Obj,
|
|
const DebugMapObject &DMO) {
|
|
// Find the debug_info section.
|
|
for (const object::SectionRef &Section : Obj.sections()) {
|
|
StringRef SectionName;
|
|
Section.getName(SectionName);
|
|
SectionName = SectionName.substr(SectionName.find_first_not_of("._"));
|
|
if (SectionName != "debug_info")
|
|
continue;
|
|
return findValidRelocs(Section, Obj, DMO);
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/// \brief Checks that there is a relocation against an actual debug
|
|
/// map entry between \p StartOffset and \p NextOffset.
|
|
///
|
|
/// This function must be called with offsets in strictly ascending
|
|
/// order because it never looks back at relocations it already 'went past'.
|
|
/// \returns true and sets Info.InDebugMap if it is the case.
|
|
bool DwarfLinker::hasValidRelocation(uint32_t StartOffset, uint32_t EndOffset,
|
|
CompileUnit::DIEInfo &Info) {
|
|
assert(NextValidReloc == 0 ||
|
|
StartOffset > ValidRelocs[NextValidReloc - 1].Offset);
|
|
if (NextValidReloc >= ValidRelocs.size())
|
|
return false;
|
|
|
|
uint64_t RelocOffset = ValidRelocs[NextValidReloc].Offset;
|
|
|
|
// We might need to skip some relocs that we didn't consider. For
|
|
// example the high_pc of a discarded DIE might contain a reloc that
|
|
// is in the list because it actually corresponds to the start of a
|
|
// function that is in the debug map.
|
|
while (RelocOffset < StartOffset && NextValidReloc < ValidRelocs.size() - 1)
|
|
RelocOffset = ValidRelocs[++NextValidReloc].Offset;
|
|
|
|
if (RelocOffset < StartOffset || RelocOffset >= EndOffset)
|
|
return false;
|
|
|
|
const auto &ValidReloc = ValidRelocs[NextValidReloc++];
|
|
const auto &Mapping = ValidReloc.Mapping->getValue();
|
|
if (Options.Verbose)
|
|
outs() << "Found valid debug map entry: " << ValidReloc.Mapping->getKey()
|
|
<< " " << format("\t%016" PRIx64 " => %016" PRIx64,
|
|
uint64_t(Mapping.ObjectAddress),
|
|
uint64_t(Mapping.BinaryAddress));
|
|
|
|
Info.AddrAdjust = int64_t(Mapping.BinaryAddress) + ValidReloc.Addend -
|
|
Mapping.ObjectAddress;
|
|
Info.InDebugMap = true;
|
|
return true;
|
|
}
|
|
|
|
/// \brief Get the starting and ending (exclusive) offset for the
|
|
/// attribute with index \p Idx descibed by \p Abbrev. \p Offset is
|
|
/// supposed to point to the position of the first attribute described
|
|
/// by \p Abbrev.
|
|
/// \return [StartOffset, EndOffset) as a pair.
|
|
static std::pair<uint32_t, uint32_t>
|
|
getAttributeOffsets(const DWARFAbbreviationDeclaration *Abbrev, unsigned Idx,
|
|
unsigned Offset, const DWARFUnit &Unit) {
|
|
DataExtractor Data = Unit.getDebugInfoExtractor();
|
|
|
|
for (unsigned i = 0; i < Idx; ++i)
|
|
DWARFFormValue::skipValue(Abbrev->getFormByIndex(i), Data, &Offset, &Unit);
|
|
|
|
uint32_t End = Offset;
|
|
DWARFFormValue::skipValue(Abbrev->getFormByIndex(Idx), Data, &End, &Unit);
|
|
|
|
return std::make_pair(Offset, End);
|
|
}
|
|
|
|
/// \brief Check if a variable describing DIE should be kept.
|
|
/// \returns updated TraversalFlags.
|
|
unsigned DwarfLinker::shouldKeepVariableDIE(
|
|
const DWARFDebugInfoEntryMinimal &DIE, CompileUnit &Unit,
|
|
CompileUnit::DIEInfo &MyInfo, unsigned Flags) {
|
|
const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
|
|
|
|
// Global variables with constant value can always be kept.
|
|
if (!(Flags & TF_InFunctionScope) &&
|
|
Abbrev->findAttributeIndex(dwarf::DW_AT_const_value) != -1U) {
|
|
MyInfo.InDebugMap = true;
|
|
return Flags | TF_Keep;
|
|
}
|
|
|
|
uint32_t LocationIdx = Abbrev->findAttributeIndex(dwarf::DW_AT_location);
|
|
if (LocationIdx == -1U)
|
|
return Flags;
|
|
|
|
uint32_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
|
|
const DWARFUnit &OrigUnit = Unit.getOrigUnit();
|
|
uint32_t LocationOffset, LocationEndOffset;
|
|
std::tie(LocationOffset, LocationEndOffset) =
|
|
getAttributeOffsets(Abbrev, LocationIdx, Offset, OrigUnit);
|
|
|
|
// See if there is a relocation to a valid debug map entry inside
|
|
// this variable's location. The order is important here. We want to
|
|
// always check in the variable has a valid relocation, so that the
|
|
// DIEInfo is filled. However, we don't want a static variable in a
|
|
// function to force us to keep the enclosing function.
|
|
if (!hasValidRelocation(LocationOffset, LocationEndOffset, MyInfo) ||
|
|
(Flags & TF_InFunctionScope))
|
|
return Flags;
|
|
|
|
if (Options.Verbose)
|
|
DIE.dump(outs(), const_cast<DWARFUnit *>(&OrigUnit), 0, 8 /* Indent */);
|
|
|
|
return Flags | TF_Keep;
|
|
}
|
|
|
|
/// \brief Check if a function describing DIE should be kept.
|
|
/// \returns updated TraversalFlags.
|
|
unsigned DwarfLinker::shouldKeepSubprogramDIE(
|
|
const DWARFDebugInfoEntryMinimal &DIE, CompileUnit &Unit,
|
|
CompileUnit::DIEInfo &MyInfo, unsigned Flags) {
|
|
const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
|
|
|
|
Flags |= TF_InFunctionScope;
|
|
|
|
uint32_t LowPcIdx = Abbrev->findAttributeIndex(dwarf::DW_AT_low_pc);
|
|
if (LowPcIdx == -1U)
|
|
return Flags;
|
|
|
|
uint32_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
|
|
const DWARFUnit &OrigUnit = Unit.getOrigUnit();
|
|
uint32_t LowPcOffset, LowPcEndOffset;
|
|
std::tie(LowPcOffset, LowPcEndOffset) =
|
|
getAttributeOffsets(Abbrev, LowPcIdx, Offset, OrigUnit);
|
|
|
|
uint64_t LowPc =
|
|
DIE.getAttributeValueAsAddress(&OrigUnit, dwarf::DW_AT_low_pc, -1ULL);
|
|
assert(LowPc != -1ULL && "low_pc attribute is not an address.");
|
|
if (LowPc == -1ULL ||
|
|
!hasValidRelocation(LowPcOffset, LowPcEndOffset, MyInfo))
|
|
return Flags;
|
|
|
|
if (Options.Verbose)
|
|
DIE.dump(outs(), const_cast<DWARFUnit *>(&OrigUnit), 0, 8 /* Indent */);
|
|
|
|
Flags |= TF_Keep;
|
|
|
|
DWARFFormValue HighPcValue;
|
|
if (!DIE.getAttributeValue(&OrigUnit, dwarf::DW_AT_high_pc, HighPcValue)) {
|
|
reportWarning("Function without high_pc. Range will be discarded.\n",
|
|
&OrigUnit, &DIE);
|
|
return Flags;
|
|
}
|
|
|
|
uint64_t HighPc;
|
|
if (HighPcValue.isFormClass(DWARFFormValue::FC_Address)) {
|
|
HighPc = *HighPcValue.getAsAddress(&OrigUnit);
|
|
} else {
|
|
assert(HighPcValue.isFormClass(DWARFFormValue::FC_Constant));
|
|
HighPc = LowPc + *HighPcValue.getAsUnsignedConstant();
|
|
}
|
|
|
|
// Replace the debug map range with a more accurate one.
|
|
Ranges[LowPc] = std::make_pair(HighPc, MyInfo.AddrAdjust);
|
|
Unit.addFunctionRange(LowPc, HighPc, MyInfo.AddrAdjust);
|
|
return Flags;
|
|
}
|
|
|
|
/// \brief Check if a DIE should be kept.
|
|
/// \returns updated TraversalFlags.
|
|
unsigned DwarfLinker::shouldKeepDIE(const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit &Unit,
|
|
CompileUnit::DIEInfo &MyInfo,
|
|
unsigned Flags) {
|
|
switch (DIE.getTag()) {
|
|
case dwarf::DW_TAG_constant:
|
|
case dwarf::DW_TAG_variable:
|
|
return shouldKeepVariableDIE(DIE, Unit, MyInfo, Flags);
|
|
case dwarf::DW_TAG_subprogram:
|
|
return shouldKeepSubprogramDIE(DIE, Unit, MyInfo, Flags);
|
|
case dwarf::DW_TAG_module:
|
|
case dwarf::DW_TAG_imported_module:
|
|
case dwarf::DW_TAG_imported_declaration:
|
|
case dwarf::DW_TAG_imported_unit:
|
|
// We always want to keep these.
|
|
return Flags | TF_Keep;
|
|
}
|
|
|
|
return Flags;
|
|
}
|
|
|
|
/// \brief Mark the passed DIE as well as all the ones it depends on
|
|
/// as kept.
|
|
///
|
|
/// This function is called by lookForDIEsToKeep on DIEs that are
|
|
/// newly discovered to be needed in the link. It recursively calls
|
|
/// back to lookForDIEsToKeep while adding TF_DependencyWalk to the
|
|
/// TraversalFlags to inform it that it's not doing the primary DIE
|
|
/// tree walk.
|
|
void DwarfLinker::keepDIEAndDenpendencies(const DWARFDebugInfoEntryMinimal &DIE,
|
|
CompileUnit::DIEInfo &MyInfo,
|
|
const DebugMapObject &DMO,
|
|
CompileUnit &CU, bool UseODR) {
|
|
const DWARFUnit &Unit = CU.getOrigUnit();
|
|
MyInfo.Keep = true;
|
|
|
|
// First mark all the parent chain as kept.
|
|
unsigned AncestorIdx = MyInfo.ParentIdx;
|
|
while (!CU.getInfo(AncestorIdx).Keep) {
|
|
unsigned ODRFlag = UseODR ? TF_ODR : 0;
|
|
lookForDIEsToKeep(*Unit.getDIEAtIndex(AncestorIdx), DMO, CU,
|
|
TF_ParentWalk | TF_Keep | TF_DependencyWalk | ODRFlag);
|
|
AncestorIdx = CU.getInfo(AncestorIdx).ParentIdx;
|
|
}
|
|
|
|
// Then we need to mark all the DIEs referenced by this DIE's
|
|
// attributes as kept.
|
|
DataExtractor Data = Unit.getDebugInfoExtractor();
|
|
const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
|
|
uint32_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
|
|
|
|
// Mark all DIEs referenced through atttributes as kept.
|
|
for (const auto &AttrSpec : Abbrev->attributes()) {
|
|
DWARFFormValue Val(AttrSpec.Form);
|
|
|
|
if (!Val.isFormClass(DWARFFormValue::FC_Reference)) {
|
|
DWARFFormValue::skipValue(AttrSpec.Form, Data, &Offset, &Unit);
|
|
continue;
|
|
}
|
|
|
|
Val.extractValue(Data, &Offset, &Unit);
|
|
CompileUnit *ReferencedCU;
|
|
if (const auto *RefDIE =
|
|
resolveDIEReference(Val, Unit, DIE, ReferencedCU)) {
|
|
uint32_t RefIdx = ReferencedCU->getOrigUnit().getDIEIndex(RefDIE);
|
|
CompileUnit::DIEInfo &Info = ReferencedCU->getInfo(RefIdx);
|
|
// If the referenced DIE has a DeclContext that has already been
|
|
// emitted, then do not keep the one in this CU. We'll link to
|
|
// the canonical DIE in cloneDieReferenceAttribute.
|
|
// FIXME: compatibility with dsymutil-classic. UseODR shouldn't
|
|
// be necessary and could be advantageously replaced by
|
|
// ReferencedCU->hasODR() && CU.hasODR().
|
|
// FIXME: compatibility with dsymutil-classic. There is no
|
|
// reason not to unique ref_addr references.
|
|
if (AttrSpec.Form != dwarf::DW_FORM_ref_addr && UseODR && Info.Ctxt &&
|
|
Info.Ctxt != ReferencedCU->getInfo(Info.ParentIdx).Ctxt &&
|
|
Info.Ctxt->getCanonicalDIEOffset() && isODRAttribute(AttrSpec.Attr))
|
|
continue;
|
|
|
|
unsigned ODRFlag = UseODR ? TF_ODR : 0;
|
|
lookForDIEsToKeep(*RefDIE, DMO, *ReferencedCU,
|
|
TF_Keep | TF_DependencyWalk | ODRFlag);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// \brief Recursively walk the \p DIE tree and look for DIEs to
|
|
/// keep. Store that information in \p CU's DIEInfo.
|
|
///
|
|
/// This function is the entry point of the DIE selection
|
|
/// algorithm. It is expected to walk the DIE tree in file order and
|
|
/// (though the mediation of its helper) call hasValidRelocation() on
|
|
/// each DIE that might be a 'root DIE' (See DwarfLinker class
|
|
/// comment).
|
|
/// While walking the dependencies of root DIEs, this function is
|
|
/// also called, but during these dependency walks the file order is
|
|
/// not respected. The TF_DependencyWalk flag tells us which kind of
|
|
/// traversal we are currently doing.
|
|
void DwarfLinker::lookForDIEsToKeep(const DWARFDebugInfoEntryMinimal &DIE,
|
|
const DebugMapObject &DMO, CompileUnit &CU,
|
|
unsigned Flags) {
|
|
unsigned Idx = CU.getOrigUnit().getDIEIndex(&DIE);
|
|
CompileUnit::DIEInfo &MyInfo = CU.getInfo(Idx);
|
|
bool AlreadyKept = MyInfo.Keep;
|
|
|
|
// If the Keep flag is set, we are marking a required DIE's
|
|
// dependencies. If our target is already marked as kept, we're all
|
|
// set.
|
|
if ((Flags & TF_DependencyWalk) && AlreadyKept)
|
|
return;
|
|
|
|
// We must not call shouldKeepDIE while called from keepDIEAndDenpendencies,
|
|
// because it would screw up the relocation finding logic.
|
|
if (!(Flags & TF_DependencyWalk))
|
|
Flags = shouldKeepDIE(DIE, CU, MyInfo, Flags);
|
|
|
|
// If it is a newly kept DIE mark it as well as all its dependencies as kept.
|
|
if (!AlreadyKept && (Flags & TF_Keep)) {
|
|
bool UseOdr = (Flags & TF_DependencyWalk) ? (Flags & TF_ODR) : CU.hasODR();
|
|
keepDIEAndDenpendencies(DIE, MyInfo, DMO, CU, UseOdr);
|
|
}
|
|
// The TF_ParentWalk flag tells us that we are currently walking up
|
|
// the parent chain of a required DIE, and we don't want to mark all
|
|
// the children of the parents as kept (consider for example a
|
|
// DW_TAG_namespace node in the parent chain). There are however a
|
|
// set of DIE types for which we want to ignore that directive and still
|
|
// walk their children.
|
|
if (dieNeedsChildrenToBeMeaningful(DIE.getTag()))
|
|
Flags &= ~TF_ParentWalk;
|
|
|
|
if (!DIE.hasChildren() || (Flags & TF_ParentWalk))
|
|
return;
|
|
|
|
for (auto *Child = DIE.getFirstChild(); Child && !Child->isNULL();
|
|
Child = Child->getSibling())
|
|
lookForDIEsToKeep(*Child, DMO, CU, Flags);
|
|
}
|
|
|
|
/// \brief Assign an abbreviation numer to \p Abbrev.
|
|
///
|
|
/// Our DIEs get freed after every DebugMapObject has been processed,
|
|
/// thus the FoldingSet we use to unique DIEAbbrevs cannot refer to
|
|
/// the instances hold by the DIEs. When we encounter an abbreviation
|
|
/// that we don't know, we create a permanent copy of it.
|
|
void DwarfLinker::AssignAbbrev(DIEAbbrev &Abbrev) {
|
|
// Check the set for priors.
|
|
FoldingSetNodeID ID;
|
|
Abbrev.Profile(ID);
|
|
void *InsertToken;
|
|
DIEAbbrev *InSet = AbbreviationsSet.FindNodeOrInsertPos(ID, InsertToken);
|
|
|
|
// If it's newly added.
|
|
if (InSet) {
|
|
// Assign existing abbreviation number.
|
|
Abbrev.setNumber(InSet->getNumber());
|
|
} else {
|
|
// Add to abbreviation list.
|
|
Abbreviations.push_back(
|
|
new DIEAbbrev(Abbrev.getTag(), Abbrev.hasChildren()));
|
|
for (const auto &Attr : Abbrev.getData())
|
|
Abbreviations.back()->AddAttribute(Attr.getAttribute(), Attr.getForm());
|
|
AbbreviationsSet.InsertNode(Abbreviations.back(), InsertToken);
|
|
// Assign the unique abbreviation number.
|
|
Abbrev.setNumber(Abbreviations.size());
|
|
Abbreviations.back()->setNumber(Abbreviations.size());
|
|
}
|
|
}
|
|
|
|
/// \brief Clone a string attribute described by \p AttrSpec and add
|
|
/// it to \p Die.
|
|
/// \returns the size of the new attribute.
|
|
unsigned DwarfLinker::cloneStringAttribute(DIE &Die, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val,
|
|
const DWARFUnit &U) {
|
|
// Switch everything to out of line strings.
|
|
const char *String = *Val.getAsCString(&U);
|
|
unsigned Offset = StringPool.getStringOffset(String);
|
|
Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr), dwarf::DW_FORM_strp,
|
|
DIEInteger(Offset));
|
|
return 4;
|
|
}
|
|
|
|
/// \brief Clone an attribute referencing another DIE and add
|
|
/// it to \p Die.
|
|
/// \returns the size of the new attribute.
|
|
unsigned DwarfLinker::cloneDieReferenceAttribute(
|
|
DIE &Die, const DWARFDebugInfoEntryMinimal &InputDIE,
|
|
AttributeSpec AttrSpec, unsigned AttrSize, const DWARFFormValue &Val,
|
|
CompileUnit &Unit) {
|
|
const DWARFUnit &U = Unit.getOrigUnit();
|
|
uint32_t Ref = *Val.getAsReference(&U);
|
|
DIE *NewRefDie = nullptr;
|
|
CompileUnit *RefUnit = nullptr;
|
|
DeclContext *Ctxt = nullptr;
|
|
|
|
const DWARFDebugInfoEntryMinimal *RefDie =
|
|
resolveDIEReference(Val, U, InputDIE, RefUnit);
|
|
|
|
// If the referenced DIE is not found, drop the attribute.
|
|
if (!RefDie)
|
|
return 0;
|
|
|
|
unsigned Idx = RefUnit->getOrigUnit().getDIEIndex(RefDie);
|
|
CompileUnit::DIEInfo &RefInfo = RefUnit->getInfo(Idx);
|
|
|
|
// If we already have emitted an equivalent DeclContext, just point
|
|
// at it.
|
|
if (isODRAttribute(AttrSpec.Attr)) {
|
|
Ctxt = RefInfo.Ctxt;
|
|
if (Ctxt && Ctxt->getCanonicalDIEOffset()) {
|
|
DIEInteger Attr(Ctxt->getCanonicalDIEOffset());
|
|
Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::DW_FORM_ref_addr, Attr);
|
|
return getRefAddrSize(U);
|
|
}
|
|
}
|
|
|
|
if (!RefInfo.Clone) {
|
|
assert(Ref > InputDIE.getOffset());
|
|
// We haven't cloned this DIE yet. Just create an empty one and
|
|
// store it. It'll get really cloned when we process it.
|
|
RefInfo.Clone = DIE::get(DIEAlloc, dwarf::Tag(RefDie->getTag()));
|
|
}
|
|
NewRefDie = RefInfo.Clone;
|
|
|
|
if (AttrSpec.Form == dwarf::DW_FORM_ref_addr ||
|
|
(Unit.hasODR() && isODRAttribute(AttrSpec.Attr))) {
|
|
// We cannot currently rely on a DIEEntry to emit ref_addr
|
|
// references, because the implementation calls back to DwarfDebug
|
|
// to find the unit offset. (We don't have a DwarfDebug)
|
|
// FIXME: we should be able to design DIEEntry reliance on
|
|
// DwarfDebug away.
|
|
uint64_t Attr;
|
|
if (Ref < InputDIE.getOffset()) {
|
|
// We must have already cloned that DIE.
|
|
uint32_t NewRefOffset =
|
|
RefUnit->getStartOffset() + NewRefDie->getOffset();
|
|
Attr = NewRefOffset;
|
|
Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::DW_FORM_ref_addr, DIEInteger(Attr));
|
|
} else {
|
|
// A forward reference. Note and fixup later.
|
|
Attr = 0xBADDEF;
|
|
Unit.noteForwardReference(
|
|
NewRefDie, RefUnit, Ctxt,
|
|
Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::DW_FORM_ref_addr, DIEInteger(Attr)));
|
|
}
|
|
return getRefAddrSize(U);
|
|
}
|
|
|
|
Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::Form(AttrSpec.Form), DIEEntry(*NewRefDie));
|
|
return AttrSize;
|
|
}
|
|
|
|
/// \brief Clone an attribute of block form (locations, constants) and add
|
|
/// it to \p Die.
|
|
/// \returns the size of the new attribute.
|
|
unsigned DwarfLinker::cloneBlockAttribute(DIE &Die, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val,
|
|
unsigned AttrSize) {
|
|
DIEValueList *Attr;
|
|
DIEValue Value;
|
|
DIELoc *Loc = nullptr;
|
|
DIEBlock *Block = nullptr;
|
|
// Just copy the block data over.
|
|
if (AttrSpec.Form == dwarf::DW_FORM_exprloc) {
|
|
Loc = new (DIEAlloc) DIELoc;
|
|
DIELocs.push_back(Loc);
|
|
} else {
|
|
Block = new (DIEAlloc) DIEBlock;
|
|
DIEBlocks.push_back(Block);
|
|
}
|
|
Attr = Loc ? static_cast<DIEValueList *>(Loc)
|
|
: static_cast<DIEValueList *>(Block);
|
|
|
|
if (Loc)
|
|
Value = DIEValue(dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::Form(AttrSpec.Form), Loc);
|
|
else
|
|
Value = DIEValue(dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::Form(AttrSpec.Form), Block);
|
|
ArrayRef<uint8_t> Bytes = *Val.getAsBlock();
|
|
for (auto Byte : Bytes)
|
|
Attr->addValue(DIEAlloc, static_cast<dwarf::Attribute>(0),
|
|
dwarf::DW_FORM_data1, DIEInteger(Byte));
|
|
// FIXME: If DIEBlock and DIELoc just reuses the Size field of
|
|
// the DIE class, this if could be replaced by
|
|
// Attr->setSize(Bytes.size()).
|
|
if (Streamer) {
|
|
if (Loc)
|
|
Loc->ComputeSize(&Streamer->getAsmPrinter());
|
|
else
|
|
Block->ComputeSize(&Streamer->getAsmPrinter());
|
|
}
|
|
Die.addValue(DIEAlloc, Value);
|
|
return AttrSize;
|
|
}
|
|
|
|
/// \brief Clone an address attribute and add it to \p Die.
|
|
/// \returns the size of the new attribute.
|
|
unsigned DwarfLinker::cloneAddressAttribute(DIE &Die, AttributeSpec AttrSpec,
|
|
const DWARFFormValue &Val,
|
|
const CompileUnit &Unit,
|
|
AttributesInfo &Info) {
|
|
uint64_t Addr = *Val.getAsAddress(&Unit.getOrigUnit());
|
|
if (AttrSpec.Attr == dwarf::DW_AT_low_pc) {
|
|
if (Die.getTag() == dwarf::DW_TAG_inlined_subroutine ||
|
|
Die.getTag() == dwarf::DW_TAG_lexical_block)
|
|
Addr += Info.PCOffset;
|
|
else if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
|
|
Addr = Unit.getLowPc();
|
|
if (Addr == UINT64_MAX)
|
|
return 0;
|
|
}
|
|
Info.HasLowPc = true;
|
|
} else if (AttrSpec.Attr == dwarf::DW_AT_high_pc) {
|
|
if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
|
|
if (uint64_t HighPc = Unit.getHighPc())
|
|
Addr = HighPc;
|
|
else
|
|
return 0;
|
|
} else
|
|
// If we have a high_pc recorded for the input DIE, use
|
|
// it. Otherwise (when no relocations where applied) just use the
|
|
// one we just decoded.
|
|
Addr = (Info.OrigHighPc ? Info.OrigHighPc : Addr) + Info.PCOffset;
|
|
}
|
|
|
|
Die.addValue(DIEAlloc, static_cast<dwarf::Attribute>(AttrSpec.Attr),
|
|
static_cast<dwarf::Form>(AttrSpec.Form), DIEInteger(Addr));
|
|
return Unit.getOrigUnit().getAddressByteSize();
|
|
}
|
|
|
|
/// \brief Clone a scalar attribute and add it to \p Die.
|
|
/// \returns the size of the new attribute.
|
|
unsigned DwarfLinker::cloneScalarAttribute(
|
|
DIE &Die, const DWARFDebugInfoEntryMinimal &InputDIE, CompileUnit &Unit,
|
|
AttributeSpec AttrSpec, const DWARFFormValue &Val, unsigned AttrSize,
|
|
AttributesInfo &Info) {
|
|
uint64_t Value;
|
|
if (AttrSpec.Attr == dwarf::DW_AT_high_pc &&
|
|
Die.getTag() == dwarf::DW_TAG_compile_unit) {
|
|
if (Unit.getLowPc() == -1ULL)
|
|
return 0;
|
|
// Dwarf >= 4 high_pc is an size, not an address.
|
|
Value = Unit.getHighPc() - Unit.getLowPc();
|
|
} else if (AttrSpec.Form == dwarf::DW_FORM_sec_offset)
|
|
Value = *Val.getAsSectionOffset();
|
|
else if (AttrSpec.Form == dwarf::DW_FORM_sdata)
|
|
Value = *Val.getAsSignedConstant();
|
|
else if (auto OptionalValue = Val.getAsUnsignedConstant())
|
|
Value = *OptionalValue;
|
|
else {
|
|
reportWarning("Unsupported scalar attribute form. Dropping attribute.",
|
|
&Unit.getOrigUnit(), &InputDIE);
|
|
return 0;
|
|
}
|
|
PatchLocation Patch =
|
|
Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
|
|
dwarf::Form(AttrSpec.Form), DIEInteger(Value));
|
|
if (AttrSpec.Attr == dwarf::DW_AT_ranges)
|
|
Unit.noteRangeAttribute(Die, Patch);
|
|
// A more generic way to check for location attributes would be
|
|
// nice, but it's very unlikely that any other attribute needs a
|
|
// location list.
|
|
else if (AttrSpec.Attr == dwarf::DW_AT_location ||
|
|
AttrSpec.Attr == dwarf::DW_AT_frame_base)
|
|
Unit.noteLocationAttribute(Patch, Info.PCOffset);
|
|
else if (AttrSpec.Attr == dwarf::DW_AT_declaration && Value)
|
|
Info.IsDeclaration = true;
|
|
|
|
return AttrSize;
|
|
}
|
|
|
|
/// \brief Clone \p InputDIE's attribute described by \p AttrSpec with
|
|
/// value \p Val, and add it to \p Die.
|
|
/// \returns the size of the cloned attribute.
|
|
unsigned DwarfLinker::cloneAttribute(DIE &Die,
|
|
const DWARFDebugInfoEntryMinimal &InputDIE,
|
|
CompileUnit &Unit,
|
|
const DWARFFormValue &Val,
|
|
const AttributeSpec AttrSpec,
|
|
unsigned AttrSize, AttributesInfo &Info) {
|
|
const DWARFUnit &U = Unit.getOrigUnit();
|
|
|
|
switch (AttrSpec.Form) {
|
|
case dwarf::DW_FORM_strp:
|
|
case dwarf::DW_FORM_string:
|
|
return cloneStringAttribute(Die, AttrSpec, Val, U);
|
|
case dwarf::DW_FORM_ref_addr:
|
|
case dwarf::DW_FORM_ref1:
|
|
case dwarf::DW_FORM_ref2:
|
|
case dwarf::DW_FORM_ref4:
|
|
case dwarf::DW_FORM_ref8:
|
|
return cloneDieReferenceAttribute(Die, InputDIE, AttrSpec, AttrSize, Val,
|
|
Unit);
|
|
case dwarf::DW_FORM_block:
|
|
case dwarf::DW_FORM_block1:
|
|
case dwarf::DW_FORM_block2:
|
|
case dwarf::DW_FORM_block4:
|
|
case dwarf::DW_FORM_exprloc:
|
|
return cloneBlockAttribute(Die, AttrSpec, Val, AttrSize);
|
|
case dwarf::DW_FORM_addr:
|
|
return cloneAddressAttribute(Die, AttrSpec, Val, Unit, Info);
|
|
case dwarf::DW_FORM_data1:
|
|
case dwarf::DW_FORM_data2:
|
|
case dwarf::DW_FORM_data4:
|
|
case dwarf::DW_FORM_data8:
|
|
case dwarf::DW_FORM_udata:
|
|
case dwarf::DW_FORM_sdata:
|
|
case dwarf::DW_FORM_sec_offset:
|
|
case dwarf::DW_FORM_flag:
|
|
case dwarf::DW_FORM_flag_present:
|
|
return cloneScalarAttribute(Die, InputDIE, Unit, AttrSpec, Val, AttrSize,
|
|
Info);
|
|
default:
|
|
reportWarning("Unsupported attribute form in cloneAttribute. Dropping.", &U,
|
|
&InputDIE);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/// \brief Apply the valid relocations found by findValidRelocs() to
|
|
/// the buffer \p Data, taking into account that Data is at \p BaseOffset
|
|
/// in the debug_info section.
|
|
///
|
|
/// Like for findValidRelocs(), this function must be called with
|
|
/// monotonic \p BaseOffset values.
|
|
///
|
|
/// \returns wether any reloc has been applied.
|
|
bool DwarfLinker::applyValidRelocs(MutableArrayRef<char> Data,
|
|
uint32_t BaseOffset, bool isLittleEndian) {
|
|
assert((NextValidReloc == 0 ||
|
|
BaseOffset > ValidRelocs[NextValidReloc - 1].Offset) &&
|
|
"BaseOffset should only be increasing.");
|
|
if (NextValidReloc >= ValidRelocs.size())
|
|
return false;
|
|
|
|
// Skip relocs that haven't been applied.
|
|
while (NextValidReloc < ValidRelocs.size() &&
|
|
ValidRelocs[NextValidReloc].Offset < BaseOffset)
|
|
++NextValidReloc;
|
|
|
|
bool Applied = false;
|
|
uint64_t EndOffset = BaseOffset + Data.size();
|
|
while (NextValidReloc < ValidRelocs.size() &&
|
|
ValidRelocs[NextValidReloc].Offset >= BaseOffset &&
|
|
ValidRelocs[NextValidReloc].Offset < EndOffset) {
|
|
const auto &ValidReloc = ValidRelocs[NextValidReloc++];
|
|
assert(ValidReloc.Offset - BaseOffset < Data.size());
|
|
assert(ValidReloc.Offset - BaseOffset + ValidReloc.Size <= Data.size());
|
|
char Buf[8];
|
|
uint64_t Value = ValidReloc.Mapping->getValue().BinaryAddress;
|
|
Value += ValidReloc.Addend;
|
|
for (unsigned i = 0; i != ValidReloc.Size; ++i) {
|
|
unsigned Index = isLittleEndian ? i : (ValidReloc.Size - i - 1);
|
|
Buf[i] = uint8_t(Value >> (Index * 8));
|
|
}
|
|
assert(ValidReloc.Size <= sizeof(Buf));
|
|
memcpy(&Data[ValidReloc.Offset - BaseOffset], Buf, ValidReloc.Size);
|
|
Applied = true;
|
|
}
|
|
|
|
return Applied;
|
|
}
|
|
|
|
static bool isTypeTag(uint16_t Tag) {
|
|
switch (Tag) {
|
|
case dwarf::DW_TAG_array_type:
|
|
case dwarf::DW_TAG_class_type:
|
|
case dwarf::DW_TAG_enumeration_type:
|
|
case dwarf::DW_TAG_pointer_type:
|
|
case dwarf::DW_TAG_reference_type:
|
|
case dwarf::DW_TAG_string_type:
|
|
case dwarf::DW_TAG_structure_type:
|
|
case dwarf::DW_TAG_subroutine_type:
|
|
case dwarf::DW_TAG_typedef:
|
|
case dwarf::DW_TAG_union_type:
|
|
case dwarf::DW_TAG_ptr_to_member_type:
|
|
case dwarf::DW_TAG_set_type:
|
|
case dwarf::DW_TAG_subrange_type:
|
|
case dwarf::DW_TAG_base_type:
|
|
case dwarf::DW_TAG_const_type:
|
|
case dwarf::DW_TAG_constant:
|
|
case dwarf::DW_TAG_file_type:
|
|
case dwarf::DW_TAG_namelist:
|
|
case dwarf::DW_TAG_packed_type:
|
|
case dwarf::DW_TAG_volatile_type:
|
|
case dwarf::DW_TAG_restrict_type:
|
|
case dwarf::DW_TAG_interface_type:
|
|
case dwarf::DW_TAG_unspecified_type:
|
|
case dwarf::DW_TAG_shared_type:
|
|
return true;
|
|
default:
|
|
break;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/// \brief Recursively clone \p InputDIE's subtrees that have been
|
|
/// selected to appear in the linked output.
|
|
///
|
|
/// \param OutOffset is the Offset where the newly created DIE will
|
|
/// lie in the linked compile unit.
|
|
///
|
|
/// \returns the cloned DIE object or null if nothing was selected.
|
|
DIE *DwarfLinker::cloneDIE(const DWARFDebugInfoEntryMinimal &InputDIE,
|
|
CompileUnit &Unit, int64_t PCOffset,
|
|
uint32_t OutOffset) {
|
|
DWARFUnit &U = Unit.getOrigUnit();
|
|
unsigned Idx = U.getDIEIndex(&InputDIE);
|
|
CompileUnit::DIEInfo &Info = Unit.getInfo(Idx);
|
|
|
|
// Should the DIE appear in the output?
|
|
if (!Unit.getInfo(Idx).Keep)
|
|
return nullptr;
|
|
|
|
uint32_t Offset = InputDIE.getOffset();
|
|
// The DIE might have been already created by a forward reference
|
|
// (see cloneDieReferenceAttribute()).
|
|
DIE *Die = Info.Clone;
|
|
if (!Die)
|
|
Die = Info.Clone = DIE::get(DIEAlloc, dwarf::Tag(InputDIE.getTag()));
|
|
assert(Die->getTag() == InputDIE.getTag());
|
|
Die->setOffset(OutOffset);
|
|
if (Unit.hasODR() && Die->getTag() != dwarf::DW_TAG_namespace && Info.Ctxt &&
|
|
Info.Ctxt != Unit.getInfo(Info.ParentIdx).Ctxt &&
|
|
!Info.Ctxt->getCanonicalDIEOffset()) {
|
|
// We are about to emit a DIE that is the root of its own valid
|
|
// DeclContext tree. Make the current offset the canonical offset
|
|
// for this context.
|
|
Info.Ctxt->setCanonicalDIEOffset(OutOffset + Unit.getStartOffset());
|
|
}
|
|
|
|
// Extract and clone every attribute.
|
|
DataExtractor Data = U.getDebugInfoExtractor();
|
|
uint32_t NextOffset = U.getDIEAtIndex(Idx + 1)->getOffset();
|
|
AttributesInfo AttrInfo;
|
|
|
|
// We could copy the data only if we need to aply a relocation to
|
|
// it. After testing, it seems there is no performance downside to
|
|
// doing the copy unconditionally, and it makes the code simpler.
|
|
SmallString<40> DIECopy(Data.getData().substr(Offset, NextOffset - Offset));
|
|
Data = DataExtractor(DIECopy, Data.isLittleEndian(), Data.getAddressSize());
|
|
// Modify the copy with relocated addresses.
|
|
if (applyValidRelocs(DIECopy, Offset, Data.isLittleEndian())) {
|
|
// If we applied relocations, we store the value of high_pc that was
|
|
// potentially stored in the input DIE. If high_pc is an address
|
|
// (Dwarf version == 2), then it might have been relocated to a
|
|
// totally unrelated value (because the end address in the object
|
|
// file might be start address of another function which got moved
|
|
// independantly by the linker). The computation of the actual
|
|
// high_pc value is done in cloneAddressAttribute().
|
|
AttrInfo.OrigHighPc =
|
|
InputDIE.getAttributeValueAsAddress(&U, dwarf::DW_AT_high_pc, 0);
|
|
}
|
|
|
|
// Reset the Offset to 0 as we will be working on the local copy of
|
|
// the data.
|
|
Offset = 0;
|
|
|
|
const auto *Abbrev = InputDIE.getAbbreviationDeclarationPtr();
|
|
Offset += getULEB128Size(Abbrev->getCode());
|
|
|
|
// We are entering a subprogram. Get and propagate the PCOffset.
|
|
if (Die->getTag() == dwarf::DW_TAG_subprogram)
|
|
PCOffset = Info.AddrAdjust;
|
|
AttrInfo.PCOffset = PCOffset;
|
|
|
|
for (const auto &AttrSpec : Abbrev->attributes()) {
|
|
DWARFFormValue Val(AttrSpec.Form);
|
|
uint32_t AttrSize = Offset;
|
|
Val.extractValue(Data, &Offset, &U);
|
|
AttrSize = Offset - AttrSize;
|
|
|
|
OutOffset +=
|
|
cloneAttribute(*Die, InputDIE, Unit, Val, AttrSpec, AttrSize, AttrInfo);
|
|
}
|
|
|
|
// Look for accelerator entries.
|
|
uint16_t Tag = InputDIE.getTag();
|
|
// FIXME: This is slightly wrong. An inline_subroutine without a
|
|
// low_pc, but with AT_ranges might be interesting to get into the
|
|
// accelerator tables too. For now stick with dsymutil's behavior.
|
|
if ((Info.InDebugMap || AttrInfo.HasLowPc) &&
|
|
Tag != dwarf::DW_TAG_compile_unit &&
|
|
getDIENames(InputDIE, Unit.getOrigUnit(), AttrInfo)) {
|
|
if (AttrInfo.MangledName && AttrInfo.MangledName != AttrInfo.Name)
|
|
Unit.addNameAccelerator(Die, AttrInfo.MangledName,
|
|
AttrInfo.MangledNameOffset,
|
|
Tag == dwarf::DW_TAG_inlined_subroutine);
|
|
if (AttrInfo.Name)
|
|
Unit.addNameAccelerator(Die, AttrInfo.Name, AttrInfo.NameOffset,
|
|
Tag == dwarf::DW_TAG_inlined_subroutine);
|
|
} else if (isTypeTag(Tag) && !AttrInfo.IsDeclaration &&
|
|
getDIENames(InputDIE, Unit.getOrigUnit(), AttrInfo)) {
|
|
Unit.addTypeAccelerator(Die, AttrInfo.Name, AttrInfo.NameOffset);
|
|
}
|
|
|
|
DIEAbbrev NewAbbrev = Die->generateAbbrev();
|
|
// If a scope DIE is kept, we must have kept at least one child. If
|
|
// it's not the case, we'll just be emitting one wasteful end of
|
|
// children marker, but things won't break.
|
|
if (InputDIE.hasChildren())
|
|
NewAbbrev.setChildrenFlag(dwarf::DW_CHILDREN_yes);
|
|
// Assign a permanent abbrev number
|
|
AssignAbbrev(NewAbbrev);
|
|
Die->setAbbrevNumber(NewAbbrev.getNumber());
|
|
|
|
// Add the size of the abbreviation number to the output offset.
|
|
OutOffset += getULEB128Size(Die->getAbbrevNumber());
|
|
|
|
if (!Abbrev->hasChildren()) {
|
|
// Update our size.
|
|
Die->setSize(OutOffset - Die->getOffset());
|
|
return Die;
|
|
}
|
|
|
|
// Recursively clone children.
|
|
for (auto *Child = InputDIE.getFirstChild(); Child && !Child->isNULL();
|
|
Child = Child->getSibling()) {
|
|
if (DIE *Clone = cloneDIE(*Child, Unit, PCOffset, OutOffset)) {
|
|
Die->addChild(Clone);
|
|
OutOffset = Clone->getOffset() + Clone->getSize();
|
|
}
|
|
}
|
|
|
|
// Account for the end of children marker.
|
|
OutOffset += sizeof(int8_t);
|
|
// Update our size.
|
|
Die->setSize(OutOffset - Die->getOffset());
|
|
return Die;
|
|
}
|
|
|
|
/// \brief Patch the input object file relevant debug_ranges entries
|
|
/// and emit them in the output file. Update the relevant attributes
|
|
/// to point at the new entries.
|
|
void DwarfLinker::patchRangesForUnit(const CompileUnit &Unit,
|
|
DWARFContext &OrigDwarf) const {
|
|
DWARFDebugRangeList RangeList;
|
|
const auto &FunctionRanges = Unit.getFunctionRanges();
|
|
unsigned AddressSize = Unit.getOrigUnit().getAddressByteSize();
|
|
DataExtractor RangeExtractor(OrigDwarf.getRangeSection(),
|
|
OrigDwarf.isLittleEndian(), AddressSize);
|
|
auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
|
|
DWARFUnit &OrigUnit = Unit.getOrigUnit();
|
|
const auto *OrigUnitDie = OrigUnit.getUnitDIE(false);
|
|
uint64_t OrigLowPc = OrigUnitDie->getAttributeValueAsAddress(
|
|
&OrigUnit, dwarf::DW_AT_low_pc, -1ULL);
|
|
// Ranges addresses are based on the unit's low_pc. Compute the
|
|
// offset we need to apply to adapt to the the new unit's low_pc.
|
|
int64_t UnitPcOffset = 0;
|
|
if (OrigLowPc != -1ULL)
|
|
UnitPcOffset = int64_t(OrigLowPc) - Unit.getLowPc();
|
|
|
|
for (const auto &RangeAttribute : Unit.getRangesAttributes()) {
|
|
uint32_t Offset = RangeAttribute.get();
|
|
RangeAttribute.set(Streamer->getRangesSectionSize());
|
|
RangeList.extract(RangeExtractor, &Offset);
|
|
const auto &Entries = RangeList.getEntries();
|
|
const DWARFDebugRangeList::RangeListEntry &First = Entries.front();
|
|
|
|
if (CurrRange == InvalidRange || First.StartAddress < CurrRange.start() ||
|
|
First.StartAddress >= CurrRange.stop()) {
|
|
CurrRange = FunctionRanges.find(First.StartAddress + OrigLowPc);
|
|
if (CurrRange == InvalidRange ||
|
|
CurrRange.start() > First.StartAddress + OrigLowPc) {
|
|
reportWarning("no mapping for range.");
|
|
continue;
|
|
}
|
|
}
|
|
|
|
Streamer->emitRangesEntries(UnitPcOffset, OrigLowPc, CurrRange, Entries,
|
|
AddressSize);
|
|
}
|
|
}
|
|
|
|
/// \brief Generate the debug_aranges entries for \p Unit and if the
|
|
/// unit has a DW_AT_ranges attribute, also emit the debug_ranges
|
|
/// contribution for this attribute.
|
|
/// FIXME: this could actually be done right in patchRangesForUnit,
|
|
/// but for the sake of initial bit-for-bit compatibility with legacy
|
|
/// dsymutil, we have to do it in a delayed pass.
|
|
void DwarfLinker::generateUnitRanges(CompileUnit &Unit) const {
|
|
auto Attr = Unit.getUnitRangesAttribute();
|
|
if (Attr)
|
|
Attr->set(Streamer->getRangesSectionSize());
|
|
Streamer->emitUnitRangesEntries(Unit, static_cast<bool>(Attr));
|
|
}
|
|
|
|
/// \brief Insert the new line info sequence \p Seq into the current
|
|
/// set of already linked line info \p Rows.
|
|
static void insertLineSequence(std::vector<DWARFDebugLine::Row> &Seq,
|
|
std::vector<DWARFDebugLine::Row> &Rows) {
|
|
if (Seq.empty())
|
|
return;
|
|
|
|
if (!Rows.empty() && Rows.back().Address < Seq.front().Address) {
|
|
Rows.insert(Rows.end(), Seq.begin(), Seq.end());
|
|
Seq.clear();
|
|
return;
|
|
}
|
|
|
|
auto InsertPoint = std::lower_bound(
|
|
Rows.begin(), Rows.end(), Seq.front(),
|
|
[](const DWARFDebugLine::Row &LHS, const DWARFDebugLine::Row &RHS) {
|
|
return LHS.Address < RHS.Address;
|
|
});
|
|
|
|
// FIXME: this only removes the unneeded end_sequence if the
|
|
// sequences have been inserted in order. using a global sort like
|
|
// described in patchLineTableForUnit() and delaying the end_sequene
|
|
// elimination to emitLineTableForUnit() we can get rid of all of them.
|
|
if (InsertPoint != Rows.end() &&
|
|
InsertPoint->Address == Seq.front().Address && InsertPoint->EndSequence) {
|
|
*InsertPoint = Seq.front();
|
|
Rows.insert(InsertPoint + 1, Seq.begin() + 1, Seq.end());
|
|
} else {
|
|
Rows.insert(InsertPoint, Seq.begin(), Seq.end());
|
|
}
|
|
|
|
Seq.clear();
|
|
}
|
|
|
|
static void patchStmtList(DIE &Die, DIEInteger Offset) {
|
|
for (auto &V : Die.values())
|
|
if (V.getAttribute() == dwarf::DW_AT_stmt_list) {
|
|
V = DIEValue(V.getAttribute(), V.getForm(), Offset);
|
|
return;
|
|
}
|
|
|
|
llvm_unreachable("Didn't find DW_AT_stmt_list in cloned DIE!");
|
|
}
|
|
|
|
/// \brief Extract the line table for \p Unit from \p OrigDwarf, and
|
|
/// recreate a relocated version of these for the address ranges that
|
|
/// are present in the binary.
|
|
void DwarfLinker::patchLineTableForUnit(CompileUnit &Unit,
|
|
DWARFContext &OrigDwarf) {
|
|
const DWARFDebugInfoEntryMinimal *CUDie = Unit.getOrigUnit().getUnitDIE();
|
|
uint64_t StmtList = CUDie->getAttributeValueAsSectionOffset(
|
|
&Unit.getOrigUnit(), dwarf::DW_AT_stmt_list, -1ULL);
|
|
if (StmtList == -1ULL)
|
|
return;
|
|
|
|
// Update the cloned DW_AT_stmt_list with the correct debug_line offset.
|
|
if (auto *OutputDIE = Unit.getOutputUnitDIE())
|
|
patchStmtList(*OutputDIE, DIEInteger(Streamer->getLineSectionSize()));
|
|
|
|
// Parse the original line info for the unit.
|
|
DWARFDebugLine::LineTable LineTable;
|
|
uint32_t StmtOffset = StmtList;
|
|
StringRef LineData = OrigDwarf.getLineSection().Data;
|
|
DataExtractor LineExtractor(LineData, OrigDwarf.isLittleEndian(),
|
|
Unit.getOrigUnit().getAddressByteSize());
|
|
LineTable.parse(LineExtractor, &OrigDwarf.getLineSection().Relocs,
|
|
&StmtOffset);
|
|
|
|
// This vector is the output line table.
|
|
std::vector<DWARFDebugLine::Row> NewRows;
|
|
NewRows.reserve(LineTable.Rows.size());
|
|
|
|
// Current sequence of rows being extracted, before being inserted
|
|
// in NewRows.
|
|
std::vector<DWARFDebugLine::Row> Seq;
|
|
const auto &FunctionRanges = Unit.getFunctionRanges();
|
|
auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
|
|
|
|
// FIXME: This logic is meant to generate exactly the same output as
|
|
// Darwin's classic dsynutil. There is a nicer way to implement this
|
|
// by simply putting all the relocated line info in NewRows and simply
|
|
// sorting NewRows before passing it to emitLineTableForUnit. This
|
|
// should be correct as sequences for a function should stay
|
|
// together in the sorted output. There are a few corner cases that
|
|
// look suspicious though, and that required to implement the logic
|
|
// this way. Revisit that once initial validation is finished.
|
|
|
|
// Iterate over the object file line info and extract the sequences
|
|
// that correspond to linked functions.
|
|
for (auto &Row : LineTable.Rows) {
|
|
// Check wether we stepped out of the range. The range is
|
|
// half-open, but consider accept the end address of the range if
|
|
// it is marked as end_sequence in the input (because in that
|
|
// case, the relocation offset is accurate and that entry won't
|
|
// serve as the start of another function).
|
|
if (CurrRange == InvalidRange || Row.Address < CurrRange.start() ||
|
|
Row.Address > CurrRange.stop() ||
|
|
(Row.Address == CurrRange.stop() && !Row.EndSequence)) {
|
|
// We just stepped out of a known range. Insert a end_sequence
|
|
// corresponding to the end of the range.
|
|
uint64_t StopAddress = CurrRange != InvalidRange
|
|
? CurrRange.stop() + CurrRange.value()
|
|
: -1ULL;
|
|
CurrRange = FunctionRanges.find(Row.Address);
|
|
bool CurrRangeValid =
|
|
CurrRange != InvalidRange && CurrRange.start() <= Row.Address;
|
|
if (!CurrRangeValid) {
|
|
CurrRange = InvalidRange;
|
|
if (StopAddress != -1ULL) {
|
|
// Try harder by looking in the DebugMapObject function
|
|
// ranges map. There are corner cases where this finds a
|
|
// valid entry. It's unclear if this is right or wrong, but
|
|
// for now do as dsymutil.
|
|
// FIXME: Understand exactly what cases this addresses and
|
|
// potentially remove it along with the Ranges map.
|
|
auto Range = Ranges.lower_bound(Row.Address);
|
|
if (Range != Ranges.begin() && Range != Ranges.end())
|
|
--Range;
|
|
|
|
if (Range != Ranges.end() && Range->first <= Row.Address &&
|
|
Range->second.first >= Row.Address) {
|
|
StopAddress = Row.Address + Range->second.second;
|
|
}
|
|
}
|
|
}
|
|
if (StopAddress != -1ULL && !Seq.empty()) {
|
|
// Insert end sequence row with the computed end address, but
|
|
// the same line as the previous one.
|
|
Seq.emplace_back(Seq.back());
|
|
Seq.back().Address = StopAddress;
|
|
Seq.back().EndSequence = 1;
|
|
Seq.back().PrologueEnd = 0;
|
|
Seq.back().BasicBlock = 0;
|
|
Seq.back().EpilogueBegin = 0;
|
|
insertLineSequence(Seq, NewRows);
|
|
}
|
|
|
|
if (!CurrRangeValid)
|
|
continue;
|
|
}
|
|
|
|
// Ignore empty sequences.
|
|
if (Row.EndSequence && Seq.empty())
|
|
continue;
|
|
|
|
// Relocate row address and add it to the current sequence.
|
|
Row.Address += CurrRange.value();
|
|
Seq.emplace_back(Row);
|
|
|
|
if (Row.EndSequence)
|
|
insertLineSequence(Seq, NewRows);
|
|
}
|
|
|
|
// Finished extracting, now emit the line tables.
|
|
uint32_t PrologueEnd = StmtList + 10 + LineTable.Prologue.PrologueLength;
|
|
// FIXME: LLVM hardcodes it's prologue values. We just copy the
|
|
// prologue over and that works because we act as both producer and
|
|
// consumer. It would be nicer to have a real configurable line
|
|
// table emitter.
|
|
if (LineTable.Prologue.Version != 2 ||
|
|
LineTable.Prologue.DefaultIsStmt != DWARF2_LINE_DEFAULT_IS_STMT ||
|
|
LineTable.Prologue.LineBase != -5 || LineTable.Prologue.LineRange != 14 ||
|
|
LineTable.Prologue.OpcodeBase != 13)
|
|
reportWarning("line table paramters mismatch. Cannot emit.");
|
|
else
|
|
Streamer->emitLineTableForUnit(LineData.slice(StmtList + 4, PrologueEnd),
|
|
LineTable.Prologue.MinInstLength, NewRows,
|
|
Unit.getOrigUnit().getAddressByteSize());
|
|
}
|
|
|
|
void DwarfLinker::emitAcceleratorEntriesForUnit(CompileUnit &Unit) {
|
|
Streamer->emitPubNamesForUnit(Unit);
|
|
Streamer->emitPubTypesForUnit(Unit);
|
|
}
|
|
|
|
/// \brief Read the frame info stored in the object, and emit the
|
|
/// patched frame descriptions for the linked binary.
|
|
///
|
|
/// This is actually pretty easy as the data of the CIEs and FDEs can
|
|
/// be considered as black boxes and moved as is. The only thing to do
|
|
/// is to patch the addresses in the headers.
|
|
void DwarfLinker::patchFrameInfoForObject(const DebugMapObject &DMO,
|
|
DWARFContext &OrigDwarf,
|
|
unsigned AddrSize) {
|
|
StringRef FrameData = OrigDwarf.getDebugFrameSection();
|
|
if (FrameData.empty())
|
|
return;
|
|
|
|
DataExtractor Data(FrameData, OrigDwarf.isLittleEndian(), 0);
|
|
uint32_t InputOffset = 0;
|
|
|
|
// Store the data of the CIEs defined in this object, keyed by their
|
|
// offsets.
|
|
DenseMap<uint32_t, StringRef> LocalCIES;
|
|
|
|
while (Data.isValidOffset(InputOffset)) {
|
|
uint32_t EntryOffset = InputOffset;
|
|
uint32_t InitialLength = Data.getU32(&InputOffset);
|
|
if (InitialLength == 0xFFFFFFFF)
|
|
return reportWarning("Dwarf64 bits no supported");
|
|
|
|
uint32_t CIEId = Data.getU32(&InputOffset);
|
|
if (CIEId == 0xFFFFFFFF) {
|
|
// This is a CIE, store it.
|
|
StringRef CIEData = FrameData.substr(EntryOffset, InitialLength + 4);
|
|
LocalCIES[EntryOffset] = CIEData;
|
|
// The -4 is to account for the CIEId we just read.
|
|
InputOffset += InitialLength - 4;
|
|
continue;
|
|
}
|
|
|
|
uint32_t Loc = Data.getUnsigned(&InputOffset, AddrSize);
|
|
|
|
// Some compilers seem to emit frame info that doesn't start at
|
|
// the function entry point, thus we can't just lookup the address
|
|
// in the debug map. Use the linker's range map to see if the FDE
|
|
// describes something that we can relocate.
|
|
auto Range = Ranges.upper_bound(Loc);
|
|
if (Range != Ranges.begin())
|
|
--Range;
|
|
if (Range == Ranges.end() || Range->first > Loc ||
|
|
Range->second.first <= Loc) {
|
|
// The +4 is to account for the size of the InitialLength field itself.
|
|
InputOffset = EntryOffset + InitialLength + 4;
|
|
continue;
|
|
}
|
|
|
|
// This is an FDE, and we have a mapping.
|
|
// Have we already emitted a corresponding CIE?
|
|
StringRef CIEData = LocalCIES[CIEId];
|
|
if (CIEData.empty())
|
|
return reportWarning("Inconsistent debug_frame content. Dropping.");
|
|
|
|
// Look if we already emitted a CIE that corresponds to the
|
|
// referenced one (the CIE data is the key of that lookup).
|
|
auto IteratorInserted = EmittedCIEs.insert(
|
|
std::make_pair(CIEData, Streamer->getFrameSectionSize()));
|
|
// If there is no CIE yet for this ID, emit it.
|
|
if (IteratorInserted.second ||
|
|
// FIXME: dsymutil-classic only caches the last used CIE for
|
|
// reuse. Mimic that behavior for now. Just removing that
|
|
// second half of the condition and the LastCIEOffset variable
|
|
// makes the code DTRT.
|
|
LastCIEOffset != IteratorInserted.first->getValue()) {
|
|
LastCIEOffset = Streamer->getFrameSectionSize();
|
|
IteratorInserted.first->getValue() = LastCIEOffset;
|
|
Streamer->emitCIE(CIEData);
|
|
}
|
|
|
|
// Emit the FDE with updated address and CIE pointer.
|
|
// (4 + AddrSize) is the size of the CIEId + initial_location
|
|
// fields that will get reconstructed by emitFDE().
|
|
unsigned FDERemainingBytes = InitialLength - (4 + AddrSize);
|
|
Streamer->emitFDE(IteratorInserted.first->getValue(), AddrSize,
|
|
Loc + Range->second.second,
|
|
FrameData.substr(InputOffset, FDERemainingBytes));
|
|
InputOffset += FDERemainingBytes;
|
|
}
|
|
}
|
|
|
|
ErrorOr<const object::ObjectFile &>
|
|
DwarfLinker::loadObject(BinaryHolder &BinaryHolder, DebugMapObject &Obj,
|
|
const DebugMap &Map) {
|
|
auto ErrOrObjs =
|
|
BinaryHolder.GetObjectFiles(Obj.getObjectFilename(), Obj.getTimestamp());
|
|
if (std::error_code EC = ErrOrObjs.getError())
|
|
reportWarning(Twine(Obj.getObjectFilename()) + ": " + EC.message());
|
|
auto ErrOrObj = BinaryHolder.Get(Map.getTriple());
|
|
if (std::error_code EC = ErrOrObj.getError())
|
|
reportWarning(Twine(Obj.getObjectFilename()) + ": " + EC.message());
|
|
return ErrOrObj;
|
|
}
|
|
|
|
bool DwarfLinker::link(const DebugMap &Map) {
|
|
|
|
if (Map.begin() == Map.end()) {
|
|
errs() << "Empty debug map.\n";
|
|
return false;
|
|
}
|
|
|
|
if (!createStreamer(Map.getTriple(), OutputFilename))
|
|
return false;
|
|
|
|
// Size of the DIEs (and headers) generated for the linked output.
|
|
uint64_t OutputDebugInfoSize = 0;
|
|
// A unique ID that identifies each compile unit.
|
|
unsigned UnitID = 0;
|
|
for (const auto &Obj : Map.objects()) {
|
|
CurrentDebugObject = Obj.get();
|
|
|
|
if (Options.Verbose)
|
|
outs() << "DEBUG MAP OBJECT: " << Obj->getObjectFilename() << "\n";
|
|
auto ErrOrObj = loadObject(BinHolder, *Obj, Map);
|
|
if (!ErrOrObj)
|
|
continue;
|
|
|
|
// Look for relocations that correspond to debug map entries.
|
|
if (!findValidRelocsInDebugInfo(*ErrOrObj, *Obj)) {
|
|
if (Options.Verbose)
|
|
outs() << "No valid relocations found. Skipping.\n";
|
|
continue;
|
|
}
|
|
|
|
// Setup access to the debug info.
|
|
DWARFContextInMemory DwarfContext(*ErrOrObj);
|
|
startDebugObject(DwarfContext, *Obj);
|
|
|
|
// In a first phase, just read in the debug info and store the DIE
|
|
// parent links that we will use during the next phase.
|
|
for (const auto &CU : DwarfContext.compile_units()) {
|
|
auto *CUDie = CU->getUnitDIE(false);
|
|
if (Options.Verbose) {
|
|
outs() << "Input compilation unit:";
|
|
CUDie->dump(outs(), CU.get(), 0);
|
|
}
|
|
Units.emplace_back(*CU, UnitID++, !Options.NoODR);
|
|
gatherDIEParents(CUDie, 0, Units.back(), &ODRContexts.getRoot(),
|
|
StringPool, ODRContexts);
|
|
}
|
|
|
|
// Then mark all the DIEs that need to be present in the linked
|
|
// output and collect some information about them. Note that this
|
|
// loop can not be merged with the previous one becaue cross-cu
|
|
// references require the ParentIdx to be setup for every CU in
|
|
// the object file before calling this.
|
|
for (auto &CurrentUnit : Units)
|
|
lookForDIEsToKeep(*CurrentUnit.getOrigUnit().getUnitDIE(), *Obj,
|
|
CurrentUnit, 0);
|
|
|
|
// The calls to applyValidRelocs inside cloneDIE will walk the
|
|
// reloc array again (in the same way findValidRelocsInDebugInfo()
|
|
// did). We need to reset the NextValidReloc index to the beginning.
|
|
NextValidReloc = 0;
|
|
|
|
// Construct the output DIE tree by cloning the DIEs we chose to
|
|
// keep above. If there are no valid relocs, then there's nothing
|
|
// to clone/emit.
|
|
if (!ValidRelocs.empty())
|
|
for (auto &CurrentUnit : Units) {
|
|
const auto *InputDIE = CurrentUnit.getOrigUnit().getUnitDIE();
|
|
CurrentUnit.setStartOffset(OutputDebugInfoSize);
|
|
DIE *OutputDIE = cloneDIE(*InputDIE, CurrentUnit, 0 /* PCOffset */,
|
|
11 /* Unit Header size */);
|
|
CurrentUnit.setOutputUnitDIE(OutputDIE);
|
|
OutputDebugInfoSize = CurrentUnit.computeNextUnitOffset();
|
|
if (Options.NoOutput)
|
|
continue;
|
|
// FIXME: for compatibility with the classic dsymutil, we emit
|
|
// an empty line table for the unit, even if the unit doesn't
|
|
// actually exist in the DIE tree.
|
|
patchLineTableForUnit(CurrentUnit, DwarfContext);
|
|
if (!OutputDIE)
|
|
continue;
|
|
patchRangesForUnit(CurrentUnit, DwarfContext);
|
|
Streamer->emitLocationsForUnit(CurrentUnit, DwarfContext);
|
|
emitAcceleratorEntriesForUnit(CurrentUnit);
|
|
}
|
|
|
|
// Emit all the compile unit's debug information.
|
|
if (!ValidRelocs.empty() && !Options.NoOutput)
|
|
for (auto &CurrentUnit : Units) {
|
|
generateUnitRanges(CurrentUnit);
|
|
CurrentUnit.fixupForwardReferences();
|
|
Streamer->emitCompileUnitHeader(CurrentUnit);
|
|
if (!CurrentUnit.getOutputUnitDIE())
|
|
continue;
|
|
Streamer->emitDIE(*CurrentUnit.getOutputUnitDIE());
|
|
}
|
|
|
|
if (!ValidRelocs.empty() && !Options.NoOutput && !Units.empty())
|
|
patchFrameInfoForObject(*Obj, DwarfContext,
|
|
Units[0].getOrigUnit().getAddressByteSize());
|
|
|
|
// Clean-up before starting working on the next object.
|
|
endDebugObject();
|
|
}
|
|
|
|
// Emit everything that's global.
|
|
if (!Options.NoOutput) {
|
|
Streamer->emitAbbrevs(Abbreviations);
|
|
Streamer->emitStrings(StringPool);
|
|
}
|
|
|
|
return Options.NoOutput ? true : Streamer->finish();
|
|
}
|
|
}
|
|
|
|
bool linkDwarf(StringRef OutputFilename, const DebugMap &DM,
|
|
const LinkOptions &Options) {
|
|
DwarfLinker Linker(OutputFilename, Options);
|
|
return Linker.link(DM);
|
|
}
|
|
}
|
|
}
|