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//===-- llvm/CodeGen/DwarfDebug.h - Dwarf Debug Framework ------*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains support for writing dwarf debug info into asm files.
//
//===----------------------------------------------------------------------===//
#ifndef CODEGEN_ASMPRINTER_DWARFDEBUG_H__
#define CODEGEN_ASMPRINTER_DWARFDEBUG_H__
#include "DIE.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/LexicalScopes.h"
#include "llvm/DebugInfo.h"
#include "llvm/MC/MachineLocation.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/DebugLoc.h"
namespace llvm {
class CompileUnit;
class ConstantInt;
class ConstantFP;
class DbgVariable;
class MachineFrameInfo;
class MachineModuleInfo;
class MachineOperand;
class MCAsmInfo;
class DIEAbbrev;
class DIE;
class DIEBlock;
class DIEEntry;
class DwarfDebug;
//===----------------------------------------------------------------------===//
/// \brief This class is used to record source line correspondence.
class SrcLineInfo {
unsigned Line; // Source line number.
unsigned Column; // Source column.
unsigned SourceID; // Source ID number.
MCSymbol *Label; // Label in code ID number.
public:
SrcLineInfo(unsigned L, unsigned C, unsigned S, MCSymbol *label)
: Line(L), Column(C), SourceID(S), Label(label) {}
// Accessors
unsigned getLine() const { return Line; }
unsigned getColumn() const { return Column; }
unsigned getSourceID() const { return SourceID; }
MCSymbol *getLabel() const { return Label; }
};
/// \brief This struct describes location entries emitted in the .debug_loc
/// section.
typedef struct DotDebugLocEntry {
const MCSymbol *Begin;
const MCSymbol *End;
MachineLocation Loc;
const MDNode *Variable;
bool Merged;
bool Constant;
enum EntryType {
E_Location,
E_Integer,
E_ConstantFP,
E_ConstantInt
};
enum EntryType EntryKind;
union {
int64_t Int;
const ConstantFP *CFP;
const ConstantInt *CIP;
} Constants;
DotDebugLocEntry()
: Begin(0), End(0), Variable(0), Merged(false),
Constant(false) { Constants.Int = 0;}
DotDebugLocEntry(const MCSymbol *B, const MCSymbol *E, MachineLocation &L,
const MDNode *V)
: Begin(B), End(E), Loc(L), Variable(V), Merged(false),
Constant(false) { Constants.Int = 0; EntryKind = E_Location; }
DotDebugLocEntry(const MCSymbol *B, const MCSymbol *E, int64_t i)
: Begin(B), End(E), Variable(0), Merged(false),
Constant(true) { Constants.Int = i; EntryKind = E_Integer; }
DotDebugLocEntry(const MCSymbol *B, const MCSymbol *E, const ConstantFP *FPtr)
: Begin(B), End(E), Variable(0), Merged(false),
Constant(true) { Constants.CFP = FPtr; EntryKind = E_ConstantFP; }
DotDebugLocEntry(const MCSymbol *B, const MCSymbol *E,
const ConstantInt *IPtr)
: Begin(B), End(E), Variable(0), Merged(false),
Constant(true) { Constants.CIP = IPtr; EntryKind = E_ConstantInt; }
/// \brief Empty entries are also used as a trigger to emit temp label. Such
/// labels are referenced is used to find debug_loc offset for a given DIE.
bool isEmpty() { return Begin == 0 && End == 0; }
bool isMerged() { return Merged; }
void Merge(DotDebugLocEntry *Next) {
if (!(Begin && Loc == Next->Loc && End == Next->Begin))
return;
Next->Begin = Begin;
Merged = true;
}
bool isLocation() const { return EntryKind == E_Location; }
bool isInt() const { return EntryKind == E_Integer; }
bool isConstantFP() const { return EntryKind == E_ConstantFP; }
bool isConstantInt() const { return EntryKind == E_ConstantInt; }
int64_t getInt() { return Constants.Int; }
const ConstantFP *getConstantFP() { return Constants.CFP; }
const ConstantInt *getConstantInt() { return Constants.CIP; }
} DotDebugLocEntry;
//===----------------------------------------------------------------------===//
/// \brief This class is used to track local variable information.
class DbgVariable {
DIVariable Var; // Variable Descriptor.
DIE *TheDIE; // Variable DIE.
unsigned DotDebugLocOffset; // Offset in DotDebugLocEntries.
DbgVariable *AbsVar; // Corresponding Abstract variable, if any.
const MachineInstr *MInsn; // DBG_VALUE instruction of the variable.
int FrameIndex;
public:
// AbsVar may be NULL.
DbgVariable(DIVariable V, DbgVariable *AV)
: Var(V), TheDIE(0), DotDebugLocOffset(~0U), AbsVar(AV), MInsn(0),
FrameIndex(~0) {}
// Accessors.
DIVariable getVariable() const { return Var; }
void setDIE(DIE *D) { TheDIE = D; }
DIE *getDIE() const { return TheDIE; }
void setDotDebugLocOffset(unsigned O) { DotDebugLocOffset = O; }
unsigned getDotDebugLocOffset() const { return DotDebugLocOffset; }
StringRef getName() const { return Var.getName(); }
DbgVariable *getAbstractVariable() const { return AbsVar; }
const MachineInstr *getMInsn() const { return MInsn; }
void setMInsn(const MachineInstr *M) { MInsn = M; }
int getFrameIndex() const { return FrameIndex; }
void setFrameIndex(int FI) { FrameIndex = FI; }
// Translate tag to proper Dwarf tag.
unsigned getTag() const {
if (Var.getTag() == dwarf::DW_TAG_arg_variable)
return dwarf::DW_TAG_formal_parameter;
return dwarf::DW_TAG_variable;
}
/// \brief Return true if DbgVariable is artificial.
bool isArtificial() const {
if (Var.isArtificial())
return true;
if (getType().isArtificial())
return true;
return false;
}
bool isObjectPointer() const {
if (Var.isObjectPointer())
return true;
if (getType().isObjectPointer())
return true;
return false;
}
bool variableHasComplexAddress() const {
assert(Var.Verify() && "Invalid complex DbgVariable!");
return Var.hasComplexAddress();
}
bool isBlockByrefVariable() const {
assert(Var.Verify() && "Invalid complex DbgVariable!");
return Var.isBlockByrefVariable();
}
unsigned getNumAddrElements() const {
assert(Var.Verify() && "Invalid complex DbgVariable!");
return Var.getNumAddrElements();
}
uint64_t getAddrElement(unsigned i) const {
return Var.getAddrElement(i);
}
DIType getType() const;
};
// A String->Symbol mapping of strings used by indirect
// references.
typedef StringMap<std::pair<MCSymbol*, unsigned>,
BumpPtrAllocator&> StrPool;
// A Symbol->pair<Symbol, unsigned> mapping of addresses used by indirect
// references.
typedef DenseMap<MCSymbol *, std::pair<MCSymbol *, unsigned> > AddrPool;
/// \brief Collects and handles information specific to a particular
/// collection of units.
class DwarfUnits {
// Target of Dwarf emission, used for sizing of abbreviations.
AsmPrinter *Asm;
// Used to uniquely define abbreviations.
FoldingSet<DIEAbbrev> *AbbreviationsSet;
// A list of all the unique abbreviations in use.
std::vector<DIEAbbrev *> *Abbreviations;
// A pointer to all units in the section.
SmallVector<CompileUnit *, 1> CUs;
// Collection of strings for this unit and assorted symbols.
StrPool StringPool;
unsigned NextStringPoolNumber;
std::string StringPref;
// Collection of addresses for this unit and assorted labels.
AddrPool AddressPool;
unsigned NextAddrPoolNumber;
public:
DwarfUnits(AsmPrinter *AP, FoldingSet<DIEAbbrev> *AS,
std::vector<DIEAbbrev *> *A, const char *Pref,
BumpPtrAllocator &DA) :
Asm(AP), AbbreviationsSet(AS), Abbreviations(A),
StringPool(DA), NextStringPoolNumber(0), StringPref(Pref),
AddressPool(), NextAddrPoolNumber(0) {}
/// \brief Compute the size and offset of a DIE given an incoming Offset.
unsigned computeSizeAndOffset(DIE *Die, unsigned Offset);
/// \brief Compute the size and offset of all the DIEs.
void computeSizeAndOffsets();
/// \brief Define a unique number for the abbreviation.
void assignAbbrevNumber(DIEAbbrev &Abbrev);
/// \brief Add a unit to the list of CUs.
void addUnit(CompileUnit *CU) { CUs.push_back(CU); }
/// \brief Emit all of the units to the section listed with the given
/// abbreviation section.
void emitUnits(DwarfDebug *, const MCSection *, const MCSection *,
const MCSymbol *);
/// \brief Emit all of the strings to the section given.
void emitStrings(const MCSection *, const MCSection *, const MCSymbol *);
/// \brief Emit all of the addresses to the section given.
void emitAddresses(const MCSection *);
/// \brief Returns the entry into the start of the pool.
MCSymbol *getStringPoolSym();
/// \brief Returns an entry into the string pool with the given
/// string text.
MCSymbol *getStringPoolEntry(StringRef Str);
/// \brief Returns the index into the string pool with the given
/// string text.
unsigned getStringPoolIndex(StringRef Str);
/// \brief Returns the string pool.
StrPool *getStringPool() { return &StringPool; }
/// \brief Returns the index into the address pool with the given
/// label/symbol.
unsigned getAddrPoolIndex(MCSymbol *);
/// \brief Returns the address pool.
AddrPool *getAddrPool() { return &AddressPool; }
/// \brief for a given compile unit DIE, returns offset from beginning of
/// debug info.
unsigned getCUOffset(DIE *Die);
};
/// \brief Collects and handles dwarf debug information.
class DwarfDebug {
// Target of Dwarf emission.
AsmPrinter *Asm;
// Collected machine module information.
MachineModuleInfo *MMI;
// All DIEValues are allocated through this allocator.
BumpPtrAllocator DIEValueAllocator;
//===--------------------------------------------------------------------===//
// Attribute used to construct specific Dwarf sections.
//
CompileUnit *FirstCU;
// Maps MDNode with its corresponding CompileUnit.
DenseMap <const MDNode *, CompileUnit *> CUMap;
// Maps subprogram MDNode with its corresponding CompileUnit.
DenseMap <const MDNode *, CompileUnit *> SPMap;
// Used to uniquely define abbreviations.
FoldingSet<DIEAbbrev> AbbreviationsSet;
// A list of all the unique abbreviations in use.
std::vector<DIEAbbrev *> Abbreviations;
// Stores the current file ID for a given compile unit.
DenseMap <unsigned, unsigned> FileIDCUMap;
// Source id map, i.e. CUID, source filename and directory,
// separated by a zero byte, mapped to a unique id.
StringMap<unsigned, BumpPtrAllocator&> SourceIdMap;
// Provides a unique id per text section.
SetVector<const MCSection*> SectionMap;
// List of Arguments (DbgValues) for current function.
SmallVector<DbgVariable *, 8> CurrentFnArguments;
LexicalScopes LScopes;
// Collection of abstract subprogram DIEs.
DenseMap<const MDNode *, DIE *> AbstractSPDies;
// Collection of dbg variables of a scope.
DenseMap<LexicalScope *, SmallVector<DbgVariable *, 8> > ScopeVariables;
// Collection of abstract variables.
DenseMap<const MDNode *, DbgVariable *> AbstractVariables;
// Collection of DotDebugLocEntry.
SmallVector<DotDebugLocEntry, 4> DotDebugLocEntries;
// Collection of subprogram DIEs that are marked (at the end of the module)
// as DW_AT_inline.
SmallPtrSet<DIE *, 4> InlinedSubprogramDIEs;
// Keep track of inlined functions and their location. This
// information is used to populate the debug_inlined section.
typedef std::pair<const MCSymbol *, DIE *> InlineInfoLabels;
DenseMap<const MDNode *, SmallVector<InlineInfoLabels, 4> > InlineInfo;
SmallVector<const MDNode *, 4> InlinedSPNodes;
// This is a collection of subprogram MDNodes that are processed to
// create DIEs.
SmallPtrSet<const MDNode *, 16> ProcessedSPNodes;
// Maps instruction with label emitted before instruction.
DenseMap<const MachineInstr *, MCSymbol *> LabelsBeforeInsn;
// Maps instruction with label emitted after instruction.
DenseMap<const MachineInstr *, MCSymbol *> LabelsAfterInsn;
// Every user variable mentioned by a DBG_VALUE instruction in order of
// appearance.
SmallVector<const MDNode*, 8> UserVariables;
// For each user variable, keep a list of DBG_VALUE instructions in order.
// The list can also contain normal instructions that clobber the previous
// DBG_VALUE.
typedef DenseMap<const MDNode*, SmallVector<const MachineInstr*, 4> >
DbgValueHistoryMap;
DbgValueHistoryMap DbgValues;
SmallVector<const MCSymbol *, 8> DebugRangeSymbols;
// Previous instruction's location information. This is used to determine
// label location to indicate scope boundries in dwarf debug info.
DebugLoc PrevInstLoc;
MCSymbol *PrevLabel;
// This location indicates end of function prologue and beginning of function
// body.
DebugLoc PrologEndLoc;
struct FunctionDebugFrameInfo {
unsigned Number;
std::vector<MachineMove> Moves;
FunctionDebugFrameInfo(unsigned Num, const std::vector<MachineMove> &M)
: Number(Num), Moves(M) {}
};
std::vector<FunctionDebugFrameInfo> DebugFrames;
// Section Symbols: these are assembler temporary labels that are emitted at
// the beginning of each supported dwarf section. These are used to form
// section offsets and are created by EmitSectionLabels.
MCSymbol *DwarfInfoSectionSym, *DwarfAbbrevSectionSym;
MCSymbol *DwarfStrSectionSym, *TextSectionSym, *DwarfDebugRangeSectionSym;
MCSymbol *DwarfDebugLocSectionSym, *DwarfLineSectionSym;
MCSymbol *FunctionBeginSym, *FunctionEndSym;
MCSymbol *DwarfAbbrevDWOSectionSym, *DwarfStrDWOSectionSym;
// As an optimization, there is no need to emit an entry in the directory
// table for the same directory as DW_at_comp_dir.
StringRef CompilationDir;
// Counter for assigning globally unique IDs for CUs.
unsigned GlobalCUIndexCount;
// Holder for the file specific debug information.
DwarfUnits InfoHolder;
// Holders for the various debug information flags that we might need to
// have exposed. See accessor functions below for description.
// Whether or not we're emitting info for older versions of gdb on darwin.
bool IsDarwinGDBCompat;
// DWARF5 Experimental Options
bool HasDwarfAccelTables;
bool HasSplitDwarf;
// Separated Dwarf Variables
// In general these will all be for bits that are left in the
// original object file, rather than things that are meant
// to be in the .dwo sections.
// The CUs left in the original object file for separated debug info.
SmallVector<CompileUnit *, 1> SkeletonCUs;
// Used to uniquely define abbreviations for the skeleton emission.
FoldingSet<DIEAbbrev> SkeletonAbbrevSet;
// A list of all the unique abbreviations in use.
std::vector<DIEAbbrev *> SkeletonAbbrevs;
// Holder for the skeleton information.
DwarfUnits SkeletonHolder;
private:
void addScopeVariable(LexicalScope *LS, DbgVariable *Var);
/// \brief Find abstract variable associated with Var.
DbgVariable *findAbstractVariable(DIVariable &Var, DebugLoc Loc);
/// \brief Find DIE for the given subprogram and attach appropriate
/// DW_AT_low_pc and DW_AT_high_pc attributes. If there are global
/// variables in this scope then create and insert DIEs for these
/// variables.
DIE *updateSubprogramScopeDIE(CompileUnit *SPCU, const MDNode *SPNode);
/// \brief Construct new DW_TAG_lexical_block for this scope and
/// attach DW_AT_low_pc/DW_AT_high_pc labels.
DIE *constructLexicalScopeDIE(CompileUnit *TheCU, LexicalScope *Scope);
/// \brief This scope represents inlined body of a function. Construct
/// DIE to represent this concrete inlined copy of the function.
DIE *constructInlinedScopeDIE(CompileUnit *TheCU, LexicalScope *Scope);
/// \brief Construct a DIE for this scope.
DIE *constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope);
/// \brief Emit initial Dwarf sections with a label at the start of each one.
void emitSectionLabels();
/// \brief Compute the size and offset of a DIE given an incoming Offset.
unsigned computeSizeAndOffset(DIE *Die, unsigned Offset);
/// \brief Compute the size and offset of all the DIEs.
void computeSizeAndOffsets();
/// \brief Attach DW_AT_inline attribute with inlined subprogram DIEs.
void computeInlinedDIEs();
/// \brief Collect info for variables that were optimized out.
void collectDeadVariables();
/// \brief Finish off debug information after all functions have been
/// processed.
void finalizeModuleInfo();
/// \brief Emit labels to close any remaining sections that have been left
/// open.
void endSections();
/// \brief Emit a set of abbreviations to the specific section.
void emitAbbrevs(const MCSection *, std::vector<DIEAbbrev*> *);
/// \brief Emit the debug info section.
void emitDebugInfo();
/// \brief Emit the abbreviation section.
void emitAbbreviations();
/// \brief Emit the last address of the section and the end of
/// the line matrix.
void emitEndOfLineMatrix(unsigned SectionEnd);
/// \brief Emit visible names into a hashed accelerator table section.
void emitAccelNames();
/// \brief Emit objective C classes and categories into a hashed
/// accelerator table section.
void emitAccelObjC();
/// \brief Emit namespace dies into a hashed accelerator table.
void emitAccelNamespaces();
/// \brief Emit type dies into a hashed accelerator table.
void emitAccelTypes();
/// \brief Emit visible names into a debug pubnames section.
void emitDebugPubnames();
/// \brief Emit visible types into a debug pubtypes section.
void emitDebugPubTypes();
/// \brief Emit visible names into a debug str section.
void emitDebugStr();
/// \brief Emit visible names into a debug loc section.
void emitDebugLoc();
/// \brief Emit visible names into a debug aranges section.
void emitDebugARanges();
/// \brief Emit visible names into a debug ranges section.
void emitDebugRanges();
/// \brief Emit visible names into a debug macinfo section.
void emitDebugMacInfo();
/// \brief Emit inline info using custom format.
void emitDebugInlineInfo();
/// DWARF 5 Experimental Split Dwarf Emitters
/// \brief Construct the split debug info compile unit for the debug info
/// section.
CompileUnit *constructSkeletonCU(const MDNode *);
/// \brief Emit the local split abbreviations.
void emitSkeletonAbbrevs(const MCSection *);
/// \brief Emit the debug info dwo section.
void emitDebugInfoDWO();
/// \brief Emit the debug abbrev dwo section.
void emitDebugAbbrevDWO();
/// \brief Emit the debug str dwo section.
void emitDebugStrDWO();
/// \brief Create new CompileUnit for the given metadata node with tag
/// DW_TAG_compile_unit.
CompileUnit *constructCompileUnit(const MDNode *N);
/// \brief Construct subprogram DIE.
void constructSubprogramDIE(CompileUnit *TheCU, const MDNode *N);
/// \brief Register a source line with debug info. Returns the unique
/// label that was emitted and which provides correspondence to the
/// source line list.
void recordSourceLine(unsigned Line, unsigned Col, const MDNode *Scope,
unsigned Flags);
/// \brief Indentify instructions that are marking the beginning of or
/// ending of a scope.
void identifyScopeMarkers();
/// \brief If Var is an current function argument that add it in
/// CurrentFnArguments list.
bool addCurrentFnArgument(const MachineFunction *MF,
DbgVariable *Var, LexicalScope *Scope);
/// \brief Populate LexicalScope entries with variables' info.
void collectVariableInfo(const MachineFunction *,
SmallPtrSet<const MDNode *, 16> &ProcessedVars);
/// \brief Collect variable information from the side table maintained
/// by MMI.
void collectVariableInfoFromMMITable(const MachineFunction * MF,
SmallPtrSet<const MDNode *, 16> &P);
/// \brief Ensure that a label will be emitted before MI.
void requestLabelBeforeInsn(const MachineInstr *MI) {
LabelsBeforeInsn.insert(std::make_pair(MI, (MCSymbol*)0));
}
/// \brief Return Label preceding the instruction.
MCSymbol *getLabelBeforeInsn(const MachineInstr *MI);
/// \brief Ensure that a label will be emitted after MI.
void requestLabelAfterInsn(const MachineInstr *MI) {
LabelsAfterInsn.insert(std::make_pair(MI, (MCSymbol*)0));
}
/// \brief Return Label immediately following the instruction.
MCSymbol *getLabelAfterInsn(const MachineInstr *MI);
public:
//===--------------------------------------------------------------------===//
// Main entry points.
//
DwarfDebug(AsmPrinter *A, Module *M);
~DwarfDebug();
/// \brief Emit all Dwarf sections that should come prior to the
/// content.
void beginModule();
/// \brief Emit all Dwarf sections that should come after the content.
void endModule();
/// \brief Gather pre-function debug information.
void beginFunction(const MachineFunction *MF);
/// \brief Gather and emit post-function debug information.
void endFunction(const MachineFunction *MF);
/// \brief Process beginning of an instruction.
void beginInstruction(const MachineInstr *MI);
/// \brief Process end of an instruction.
void endInstruction(const MachineInstr *MI);
/// \brief Look up the source id with the given directory and source file
/// names. If none currently exists, create a new id and insert it in the
/// SourceIds map.
unsigned getOrCreateSourceID(StringRef DirName, StringRef FullName,
unsigned CUID);
/// \brief Recursively Emits a debug information entry.
void emitDIE(DIE *Die, std::vector<DIEAbbrev *> *Abbrevs);
/// \brief Returns whether or not to limit some of our debug
/// output to the limitations of darwin gdb.
bool useDarwinGDBCompat() { return IsDarwinGDBCompat; }
// Experimental DWARF5 features.
/// \brief Returns whether or not to emit tables that dwarf consumers can
/// use to accelerate lookup.
bool useDwarfAccelTables() { return HasDwarfAccelTables; }
/// \brief Returns whether or not to change the current debug info for the
/// split dwarf proposal support.
bool useSplitDwarf() { return HasSplitDwarf; }
};
} // End of namespace llvm
#endif