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Diffstat (limited to 'contrib/llvm/include/llvm/CodeGen/DIE.h')
| -rw-r--r-- | contrib/llvm/include/llvm/CodeGen/DIE.h | 816 |
1 files changed, 816 insertions, 0 deletions
diff --git a/contrib/llvm/include/llvm/CodeGen/DIE.h b/contrib/llvm/include/llvm/CodeGen/DIE.h new file mode 100644 index 0000000..f07712a --- /dev/null +++ b/contrib/llvm/include/llvm/CodeGen/DIE.h @@ -0,0 +1,816 @@ +//===--- lib/CodeGen/DIE.h - DWARF Info Entries -----------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Data structures for DWARF info entries. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DIE_H +#define LLVM_LIB_CODEGEN_ASMPRINTER_DIE_H + +#include "llvm/ADT/FoldingSet.h" +#include "llvm/ADT/PointerIntPair.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/CodeGen/DwarfStringPoolEntry.h" +#include "llvm/Support/Dwarf.h" +#include <vector> + +namespace llvm { +class AsmPrinter; +class MCExpr; +class MCSymbol; +class raw_ostream; +class DwarfTypeUnit; + +//===--------------------------------------------------------------------===// +/// DIEAbbrevData - Dwarf abbreviation data, describes one attribute of a +/// Dwarf abbreviation. +class DIEAbbrevData { + /// Attribute - Dwarf attribute code. + /// + dwarf::Attribute Attribute; + + /// Form - Dwarf form code. + /// + dwarf::Form Form; + +public: + DIEAbbrevData(dwarf::Attribute A, dwarf::Form F) : Attribute(A), Form(F) {} + + // Accessors. + dwarf::Attribute getAttribute() const { return Attribute; } + dwarf::Form getForm() const { return Form; } + + /// Profile - Used to gather unique data for the abbreviation folding set. + /// + void Profile(FoldingSetNodeID &ID) const; +}; + +//===--------------------------------------------------------------------===// +/// DIEAbbrev - Dwarf abbreviation, describes the organization of a debug +/// information object. +class DIEAbbrev : public FoldingSetNode { + /// Unique number for node. + /// + unsigned Number; + + /// Tag - Dwarf tag code. + /// + dwarf::Tag Tag; + + /// Children - Whether or not this node has children. + /// + // This cheats a bit in all of the uses since the values in the standard + // are 0 and 1 for no children and children respectively. + bool Children; + + /// Data - Raw data bytes for abbreviation. + /// + SmallVector<DIEAbbrevData, 12> Data; + +public: + DIEAbbrev(dwarf::Tag T, bool C) : Tag(T), Children(C), Data() {} + + // Accessors. + dwarf::Tag getTag() const { return Tag; } + unsigned getNumber() const { return Number; } + bool hasChildren() const { return Children; } + const SmallVectorImpl<DIEAbbrevData> &getData() const { return Data; } + void setChildrenFlag(bool hasChild) { Children = hasChild; } + void setNumber(unsigned N) { Number = N; } + + /// AddAttribute - Adds another set of attribute information to the + /// abbreviation. + void AddAttribute(dwarf::Attribute Attribute, dwarf::Form Form) { + Data.push_back(DIEAbbrevData(Attribute, Form)); + } + + /// Profile - Used to gather unique data for the abbreviation folding set. + /// + void Profile(FoldingSetNodeID &ID) const; + + /// Emit - Print the abbreviation using the specified asm printer. + /// + void Emit(const AsmPrinter *AP) const; + +#ifndef NDEBUG + void print(raw_ostream &O); + void dump(); +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEInteger - An integer value DIE. +/// +class DIEInteger { + uint64_t Integer; + +public: + explicit DIEInteger(uint64_t I) : Integer(I) {} + + /// BestForm - Choose the best form for integer. + /// + static dwarf::Form BestForm(bool IsSigned, uint64_t Int) { + if (IsSigned) { + const int64_t SignedInt = Int; + if ((char)Int == SignedInt) + return dwarf::DW_FORM_data1; + if ((short)Int == SignedInt) + return dwarf::DW_FORM_data2; + if ((int)Int == SignedInt) + return dwarf::DW_FORM_data4; + } else { + if ((unsigned char)Int == Int) + return dwarf::DW_FORM_data1; + if ((unsigned short)Int == Int) + return dwarf::DW_FORM_data2; + if ((unsigned int)Int == Int) + return dwarf::DW_FORM_data4; + } + return dwarf::DW_FORM_data8; + } + + uint64_t getValue() const { return Integer; } + void setValue(uint64_t Val) { Integer = Val; } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEExpr - An expression DIE. +// +class DIEExpr { + const MCExpr *Expr; + +public: + explicit DIEExpr(const MCExpr *E) : Expr(E) {} + + /// getValue - Get MCExpr. + /// + const MCExpr *getValue() const { return Expr; } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIELabel - A label DIE. +// +class DIELabel { + const MCSymbol *Label; + +public: + explicit DIELabel(const MCSymbol *L) : Label(L) {} + + /// getValue - Get MCSymbol. + /// + const MCSymbol *getValue() const { return Label; } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEDelta - A simple label difference DIE. +/// +class DIEDelta { + const MCSymbol *LabelHi; + const MCSymbol *LabelLo; + +public: + DIEDelta(const MCSymbol *Hi, const MCSymbol *Lo) : LabelHi(Hi), LabelLo(Lo) {} + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEString - A container for string values. +/// +class DIEString { + DwarfStringPoolEntryRef S; + +public: + DIEString(DwarfStringPoolEntryRef S) : S(S) {} + + /// getString - Grab the string out of the object. + StringRef getString() const { return S.getString(); } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEEntry - A pointer to another debug information entry. An instance of +/// this class can also be used as a proxy for a debug information entry not +/// yet defined (ie. types.) +class DIE; +class DIEEntry { + DIE *Entry; + + DIEEntry() = delete; + +public: + explicit DIEEntry(DIE &E) : Entry(&E) {} + + DIE &getEntry() const { return *Entry; } + + /// Returns size of a ref_addr entry. + static unsigned getRefAddrSize(const AsmPrinter *AP); + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const { + return Form == dwarf::DW_FORM_ref_addr ? getRefAddrSize(AP) + : sizeof(int32_t); + } + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// \brief A signature reference to a type unit. +class DIETypeSignature { + const DwarfTypeUnit *Unit; + + DIETypeSignature() = delete; + +public: + explicit DIETypeSignature(const DwarfTypeUnit &Unit) : Unit(&Unit) {} + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const { + assert(Form == dwarf::DW_FORM_ref_sig8); + return 8; + } + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIELocList - Represents a pointer to a location list in the debug_loc +/// section. +// +class DIELocList { + // Index into the .debug_loc vector. + size_t Index; + +public: + DIELocList(size_t I) : Index(I) {} + + /// getValue - Grab the current index out. + size_t getValue() const { return Index; } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEValue - A debug information entry value. Some of these roughly correlate +/// to DWARF attribute classes. +/// +class DIEBlock; +class DIELoc; +class DIEValue { +public: + enum Type { + isNone, +#define HANDLE_DIEVALUE(T) is##T, +#include "llvm/CodeGen/DIEValue.def" + }; + +private: + /// Ty - Type of data stored in the value. + /// + Type Ty = isNone; + dwarf::Attribute Attribute = (dwarf::Attribute)0; + dwarf::Form Form = (dwarf::Form)0; + + /// Storage for the value. + /// + /// All values that aren't standard layout (or are larger than 8 bytes) + /// should be stored by reference instead of by value. + typedef AlignedCharArrayUnion<DIEInteger, DIEString, DIEExpr, DIELabel, + DIEDelta *, DIEEntry, DIETypeSignature, + DIEBlock *, DIELoc *, DIELocList> ValTy; + static_assert(sizeof(ValTy) <= sizeof(uint64_t) || + sizeof(ValTy) <= sizeof(void *), + "Expected all large types to be stored via pointer"); + + /// Underlying stored value. + ValTy Val; + + template <class T> void construct(T V) { + static_assert(std::is_standard_layout<T>::value || + std::is_pointer<T>::value, + "Expected standard layout or pointer"); + new (reinterpret_cast<void *>(Val.buffer)) T(V); + } + + template <class T> T *get() { return reinterpret_cast<T *>(Val.buffer); } + template <class T> const T *get() const { + return reinterpret_cast<const T *>(Val.buffer); + } + template <class T> void destruct() { get<T>()->~T(); } + + /// Destroy the underlying value. + /// + /// This should get optimized down to a no-op. We could skip it if we could + /// add a static assert on \a std::is_trivially_copyable(), but we currently + /// support versions of GCC that don't understand that. + void destroyVal() { + switch (Ty) { + case isNone: + return; +#define HANDLE_DIEVALUE_SMALL(T) \ + case is##T: \ + destruct<DIE##T>(); + return; +#define HANDLE_DIEVALUE_LARGE(T) \ + case is##T: \ + destruct<const DIE##T *>(); + return; +#include "llvm/CodeGen/DIEValue.def" + } + } + + /// Copy the underlying value. + /// + /// This should get optimized down to a simple copy. We need to actually + /// construct the value, rather than calling memcpy, to satisfy strict + /// aliasing rules. + void copyVal(const DIEValue &X) { + switch (Ty) { + case isNone: + return; +#define HANDLE_DIEVALUE_SMALL(T) \ + case is##T: \ + construct<DIE##T>(*X.get<DIE##T>()); \ + return; +#define HANDLE_DIEVALUE_LARGE(T) \ + case is##T: \ + construct<const DIE##T *>(*X.get<const DIE##T *>()); \ + return; +#include "llvm/CodeGen/DIEValue.def" + } + } + +public: + DIEValue() = default; + DIEValue(const DIEValue &X) : Ty(X.Ty), Attribute(X.Attribute), Form(X.Form) { + copyVal(X); + } + DIEValue &operator=(const DIEValue &X) { + destroyVal(); + Ty = X.Ty; + Attribute = X.Attribute; + Form = X.Form; + copyVal(X); + return *this; + } + ~DIEValue() { destroyVal(); } + +#define HANDLE_DIEVALUE_SMALL(T) \ + DIEValue(dwarf::Attribute Attribute, dwarf::Form Form, const DIE##T &V) \ + : Ty(is##T), Attribute(Attribute), Form(Form) { \ + construct<DIE##T>(V); \ + } +#define HANDLE_DIEVALUE_LARGE(T) \ + DIEValue(dwarf::Attribute Attribute, dwarf::Form Form, const DIE##T *V) \ + : Ty(is##T), Attribute(Attribute), Form(Form) { \ + assert(V && "Expected valid value"); \ + construct<const DIE##T *>(V); \ + } +#include "llvm/CodeGen/DIEValue.def" + + // Accessors + Type getType() const { return Ty; } + dwarf::Attribute getAttribute() const { return Attribute; } + dwarf::Form getForm() const { return Form; } + explicit operator bool() const { return Ty; } + +#define HANDLE_DIEVALUE_SMALL(T) \ + const DIE##T &getDIE##T() const { \ + assert(getType() == is##T && "Expected " #T); \ + return *get<DIE##T>(); \ + } +#define HANDLE_DIEVALUE_LARGE(T) \ + const DIE##T &getDIE##T() const { \ + assert(getType() == is##T && "Expected " #T); \ + return **get<const DIE##T *>(); \ + } +#include "llvm/CodeGen/DIEValue.def" + + /// EmitValue - Emit value via the Dwarf writer. + /// + void EmitValue(const AsmPrinter *AP) const; + + /// SizeOf - Return the size of a value in bytes. + /// + unsigned SizeOf(const AsmPrinter *AP) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; + void dump() const; +#endif +}; + +struct IntrusiveBackListNode { + PointerIntPair<IntrusiveBackListNode *, 1> Next; + IntrusiveBackListNode() : Next(this, true) {} + + IntrusiveBackListNode *getNext() const { + return Next.getInt() ? nullptr : Next.getPointer(); + } +}; + +struct IntrusiveBackListBase { + typedef IntrusiveBackListNode Node; + Node *Last = nullptr; + + bool empty() const { return !Last; } + void push_back(Node &N) { + assert(N.Next.getPointer() == &N && "Expected unlinked node"); + assert(N.Next.getInt() == true && "Expected unlinked node"); + + if (Last) { + N.Next = Last->Next; + Last->Next.setPointerAndInt(&N, false); + } + Last = &N; + } +}; + +template <class T> class IntrusiveBackList : IntrusiveBackListBase { +public: + using IntrusiveBackListBase::empty; + void push_back(T &N) { IntrusiveBackListBase::push_back(N); } + T &back() { return *static_cast<T *>(Last); } + const T &back() const { return *static_cast<T *>(Last); } + + class const_iterator; + class iterator + : public iterator_facade_base<iterator, std::forward_iterator_tag, T> { + friend class const_iterator; + Node *N = nullptr; + + public: + iterator() = default; + explicit iterator(T *N) : N(N) {} + + iterator &operator++() { + N = N->getNext(); + return *this; + } + + explicit operator bool() const { return N; } + T &operator*() const { return *static_cast<T *>(N); } + + bool operator==(const iterator &X) const { return N == X.N; } + bool operator!=(const iterator &X) const { return N != X.N; } + }; + + class const_iterator + : public iterator_facade_base<const_iterator, std::forward_iterator_tag, + const T> { + const Node *N = nullptr; + + public: + const_iterator() = default; + // Placate MSVC by explicitly scoping 'iterator'. + const_iterator(typename IntrusiveBackList<T>::iterator X) : N(X.N) {} + explicit const_iterator(const T *N) : N(N) {} + + const_iterator &operator++() { + N = N->getNext(); + return *this; + } + + explicit operator bool() const { return N; } + const T &operator*() const { return *static_cast<const T *>(N); } + + bool operator==(const const_iterator &X) const { return N == X.N; } + bool operator!=(const const_iterator &X) const { return N != X.N; } + }; + + iterator begin() { + return Last ? iterator(static_cast<T *>(Last->Next.getPointer())) : end(); + } + const_iterator begin() const { + return const_cast<IntrusiveBackList *>(this)->begin(); + } + iterator end() { return iterator(); } + const_iterator end() const { return const_iterator(); } + + static iterator toIterator(T &N) { return iterator(&N); } + static const_iterator toIterator(const T &N) { return const_iterator(&N); } +}; + +/// A list of DIE values. +/// +/// This is a singly-linked list, but instead of reversing the order of +/// insertion, we keep a pointer to the back of the list so we can push in +/// order. +/// +/// There are two main reasons to choose a linked list over a customized +/// vector-like data structure. +/// +/// 1. For teardown efficiency, we want DIEs to be BumpPtrAllocated. Using a +/// linked list here makes this way easier to accomplish. +/// 2. Carrying an extra pointer per \a DIEValue isn't expensive. 45% of DIEs +/// have 2 or fewer values, and 90% have 5 or fewer. A vector would be +/// over-allocated by 50% on average anyway, the same cost as the +/// linked-list node. +class DIEValueList { + struct Node : IntrusiveBackListNode { + DIEValue V; + explicit Node(DIEValue V) : V(V) {} + }; + + typedef IntrusiveBackList<Node> ListTy; + ListTy List; + +public: + bool empty() const { return List.empty(); } + + class const_iterator; + class iterator + : public iterator_adaptor_base<iterator, ListTy::iterator, + std::forward_iterator_tag, DIEValue> { + friend class const_iterator; + typedef iterator_adaptor_base<iterator, ListTy::iterator, + std::forward_iterator_tag, + DIEValue> iterator_adaptor; + + public: + iterator() = default; + explicit iterator(ListTy::iterator X) : iterator_adaptor(X) {} + + explicit operator bool() const { return bool(wrapped()); } + DIEValue &operator*() const { return wrapped()->V; } + }; + + class const_iterator + : public iterator_adaptor_base<const_iterator, ListTy::const_iterator, + std::forward_iterator_tag, + const DIEValue> { + typedef iterator_adaptor_base<const_iterator, ListTy::const_iterator, + std::forward_iterator_tag, + const DIEValue> iterator_adaptor; + + public: + const_iterator() = default; + const_iterator(DIEValueList::iterator X) : iterator_adaptor(X.wrapped()) {} + explicit const_iterator(ListTy::const_iterator X) : iterator_adaptor(X) {} + + explicit operator bool() const { return bool(wrapped()); } + const DIEValue &operator*() const { return wrapped()->V; } + }; + + iterator insert(BumpPtrAllocator &Alloc, DIEValue V) { + List.push_back(*new (Alloc) Node(V)); + return iterator(ListTy::toIterator(List.back())); + } + template <class... Ts> + iterator emplace(BumpPtrAllocator &Alloc, Ts &&... Args) { + return insert(Alloc, DIEValue(std::forward<Ts>(Args)...)); + } + + iterator begin() { return iterator(List.begin()); } + iterator end() { return iterator(List.end()); } + const_iterator begin() const { return const_iterator(List.begin()); } + const_iterator end() const { return const_iterator(List.end()); } +}; + +//===--------------------------------------------------------------------===// +/// DIE - A structured debug information entry. Has an abbreviation which +/// describes its organization. +class DIE : IntrusiveBackListNode { + friend class IntrusiveBackList<DIE>; + +protected: + /// Offset - Offset in debug info section. + /// + unsigned Offset; + + /// Size - Size of instance + children. + /// + unsigned Size; + + unsigned AbbrevNumber = ~0u; + + /// Tag - Dwarf tag code. + /// + dwarf::Tag Tag = (dwarf::Tag)0; + + /// Children DIEs. + IntrusiveBackList<DIE> Children; + + DIE *Parent = nullptr; + + /// Attribute values. + /// + DIEValueList Values; + +protected: + DIE() : Offset(0), Size(0) {} + +private: + explicit DIE(dwarf::Tag Tag) : Offset(0), Size(0), Tag(Tag) {} + +public: + static DIE *get(BumpPtrAllocator &Alloc, dwarf::Tag Tag) { + return new (Alloc) DIE(Tag); + } + + // Accessors. + unsigned getAbbrevNumber() const { return AbbrevNumber; } + dwarf::Tag getTag() const { return Tag; } + unsigned getOffset() const { return Offset; } + unsigned getSize() const { return Size; } + bool hasChildren() const { return !Children.empty(); } + + typedef IntrusiveBackList<DIE>::iterator child_iterator; + typedef IntrusiveBackList<DIE>::const_iterator const_child_iterator; + typedef iterator_range<child_iterator> child_range; + typedef iterator_range<const_child_iterator> const_child_range; + + child_range children() { + return llvm::make_range(Children.begin(), Children.end()); + } + const_child_range children() const { + return llvm::make_range(Children.begin(), Children.end()); + } + + typedef DIEValueList::iterator value_iterator; + typedef iterator_range<value_iterator> value_range; + + value_range values() { + return llvm::make_range(Values.begin(), Values.end()); + } + + typedef DIEValueList::const_iterator const_value_iterator; + typedef iterator_range<const_value_iterator> const_value_range; + + const_value_range values() const { + return llvm::make_range(Values.begin(), Values.end()); + } + + DIE *getParent() const { return Parent; } + + /// Generate the abbreviation for this DIE. + /// + /// Calculate the abbreviation for this, which should be uniqued and + /// eventually used to call \a setAbbrevNumber(). + DIEAbbrev generateAbbrev() const; + + /// Set the abbreviation number for this DIE. + void setAbbrevNumber(unsigned I) { AbbrevNumber = I; } + + /// Climb up the parent chain to get the compile or type unit DIE this DIE + /// belongs to. + const DIE *getUnit() const; + /// Similar to getUnit, returns null when DIE is not added to an + /// owner yet. + const DIE *getUnitOrNull() const; + void setOffset(unsigned O) { Offset = O; } + void setSize(unsigned S) { Size = S; } + + /// addValue - Add a value and attributes to a DIE. + /// + value_iterator addValue(BumpPtrAllocator &Alloc, DIEValue Value) { + return Values.insert(Alloc, Value); + } + template <class T> + value_iterator addValue(BumpPtrAllocator &Alloc, dwarf::Attribute Attribute, + dwarf::Form Form, T &&Value) { + return Values.emplace(Alloc, Attribute, Form, std::forward<T>(Value)); + } + + /// Add a child to the DIE. + DIE &addChild(DIE *Child) { + assert(!Child->getParent() && "Child should be orphaned"); + Child->Parent = this; + Children.push_back(*Child); + return Children.back(); + } + + /// Find a value in the DIE with the attribute given. + /// + /// Returns a default-constructed DIEValue (where \a DIEValue::getType() + /// gives \a DIEValue::isNone) if no such attribute exists. + DIEValue findAttribute(dwarf::Attribute Attribute) const; + +#ifndef NDEBUG + void print(raw_ostream &O, unsigned IndentCount = 0) const; + void dump(); +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIELoc - Represents an expression location. +// +class DIELoc : public DIE { + mutable unsigned Size; // Size in bytes excluding size header. + +public: + DIELoc() : Size(0) {} + + /// ComputeSize - Calculate the size of the location expression. + /// + unsigned ComputeSize(const AsmPrinter *AP) const; + + /// BestForm - Choose the best form for data. + /// + dwarf::Form BestForm(unsigned DwarfVersion) const { + if (DwarfVersion > 3) + return dwarf::DW_FORM_exprloc; + // Pre-DWARF4 location expressions were blocks and not exprloc. + if ((unsigned char)Size == Size) + return dwarf::DW_FORM_block1; + if ((unsigned short)Size == Size) + return dwarf::DW_FORM_block2; + if ((unsigned int)Size == Size) + return dwarf::DW_FORM_block4; + return dwarf::DW_FORM_block; + } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +//===--------------------------------------------------------------------===// +/// DIEBlock - Represents a block of values. +// +class DIEBlock : public DIE { + mutable unsigned Size; // Size in bytes excluding size header. + +public: + DIEBlock() : Size(0) {} + + /// ComputeSize - Calculate the size of the location expression. + /// + unsigned ComputeSize(const AsmPrinter *AP) const; + + /// BestForm - Choose the best form for data. + /// + dwarf::Form BestForm() const { + if ((unsigned char)Size == Size) + return dwarf::DW_FORM_block1; + if ((unsigned short)Size == Size) + return dwarf::DW_FORM_block2; + if ((unsigned int)Size == Size) + return dwarf::DW_FORM_block4; + return dwarf::DW_FORM_block; + } + + void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const; + unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const; + +#ifndef NDEBUG + void print(raw_ostream &O) const; +#endif +}; + +} // end llvm namespace + +#endif |
