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-rw-r--r--contrib/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp1478
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diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
new file mode 100644
index 0000000..f4b15ba
--- /dev/null
+++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -0,0 +1,1478 @@
+//===-- llvm/CodeGen/DwarfUnit.cpp - Dwarf Type and Compile Units ---------===//
+//
+// 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 constructing a dwarf compile unit.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DwarfUnit.h"
+#include "DwarfAccelTable.h"
+#include "DwarfCompileUnit.h"
+#include "DwarfDebug.h"
+#include "DwarfExpression.h"
+#include "llvm/ADT/APFloat.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DIBuilder.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetFrameLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "dwarfdebug"
+
+static cl::opt<bool>
+GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
+ cl::desc("Generate DWARF4 type units."),
+ cl::init(false));
+
+DIEDwarfExpression::DIEDwarfExpression(const AsmPrinter &AP, DwarfUnit &DU,
+ DIELoc &DIE)
+ : DwarfExpression(*AP.MF->getSubtarget().getRegisterInfo(),
+ AP.getDwarfDebug()->getDwarfVersion()),
+ AP(AP), DU(DU), DIE(DIE) {}
+
+void DIEDwarfExpression::EmitOp(uint8_t Op, const char* Comment) {
+ DU.addUInt(DIE, dwarf::DW_FORM_data1, Op);
+}
+void DIEDwarfExpression::EmitSigned(int64_t Value) {
+ DU.addSInt(DIE, dwarf::DW_FORM_sdata, Value);
+}
+void DIEDwarfExpression::EmitUnsigned(uint64_t Value) {
+ DU.addUInt(DIE, dwarf::DW_FORM_udata, Value);
+}
+bool DIEDwarfExpression::isFrameRegister(unsigned MachineReg) {
+ return MachineReg == TRI.getFrameRegister(*AP.MF);
+}
+
+DwarfUnit::DwarfUnit(unsigned UID, dwarf::Tag UnitTag,
+ const DICompileUnit *Node, AsmPrinter *A, DwarfDebug *DW,
+ DwarfFile *DWU)
+ : UniqueID(UID), CUNode(Node), UnitDie(UnitTag), DebugInfoOffset(0), Asm(A),
+ DD(DW), DU(DWU), IndexTyDie(nullptr), Section(nullptr) {
+ assert(UnitTag == dwarf::DW_TAG_compile_unit ||
+ UnitTag == dwarf::DW_TAG_type_unit);
+}
+
+DwarfTypeUnit::DwarfTypeUnit(unsigned UID, DwarfCompileUnit &CU, AsmPrinter *A,
+ DwarfDebug *DW, DwarfFile *DWU,
+ MCDwarfDwoLineTable *SplitLineTable)
+ : DwarfUnit(UID, dwarf::DW_TAG_type_unit, CU.getCUNode(), A, DW, DWU),
+ CU(CU), SplitLineTable(SplitLineTable) {
+ if (SplitLineTable)
+ addSectionOffset(UnitDie, dwarf::DW_AT_stmt_list, 0);
+}
+
+DwarfUnit::~DwarfUnit() {
+ for (unsigned j = 0, M = DIEBlocks.size(); j < M; ++j)
+ DIEBlocks[j]->~DIEBlock();
+ for (unsigned j = 0, M = DIELocs.size(); j < M; ++j)
+ DIELocs[j]->~DIELoc();
+}
+
+int64_t DwarfUnit::getDefaultLowerBound() const {
+ switch (getLanguage()) {
+ default:
+ break;
+
+ case dwarf::DW_LANG_C89:
+ case dwarf::DW_LANG_C99:
+ case dwarf::DW_LANG_C:
+ case dwarf::DW_LANG_C_plus_plus:
+ case dwarf::DW_LANG_ObjC:
+ case dwarf::DW_LANG_ObjC_plus_plus:
+ return 0;
+
+ case dwarf::DW_LANG_Fortran77:
+ case dwarf::DW_LANG_Fortran90:
+ case dwarf::DW_LANG_Fortran95:
+ return 1;
+
+ // The languages below have valid values only if the DWARF version >= 4.
+ case dwarf::DW_LANG_Java:
+ case dwarf::DW_LANG_Python:
+ case dwarf::DW_LANG_UPC:
+ case dwarf::DW_LANG_D:
+ if (dwarf::DWARF_VERSION >= 4)
+ return 0;
+ break;
+
+ case dwarf::DW_LANG_Ada83:
+ case dwarf::DW_LANG_Ada95:
+ case dwarf::DW_LANG_Cobol74:
+ case dwarf::DW_LANG_Cobol85:
+ case dwarf::DW_LANG_Modula2:
+ case dwarf::DW_LANG_Pascal83:
+ case dwarf::DW_LANG_PLI:
+ if (dwarf::DWARF_VERSION >= 4)
+ return 1;
+ break;
+
+ // The languages below have valid values only if the DWARF version >= 5.
+ case dwarf::DW_LANG_OpenCL:
+ case dwarf::DW_LANG_Go:
+ case dwarf::DW_LANG_Haskell:
+ case dwarf::DW_LANG_C_plus_plus_03:
+ case dwarf::DW_LANG_C_plus_plus_11:
+ case dwarf::DW_LANG_OCaml:
+ case dwarf::DW_LANG_Rust:
+ case dwarf::DW_LANG_C11:
+ case dwarf::DW_LANG_Swift:
+ case dwarf::DW_LANG_Dylan:
+ case dwarf::DW_LANG_C_plus_plus_14:
+ if (dwarf::DWARF_VERSION >= 5)
+ return 0;
+ break;
+
+ case dwarf::DW_LANG_Modula3:
+ case dwarf::DW_LANG_Julia:
+ case dwarf::DW_LANG_Fortran03:
+ case dwarf::DW_LANG_Fortran08:
+ if (dwarf::DWARF_VERSION >= 5)
+ return 1;
+ break;
+ }
+
+ return -1;
+}
+
+/// Check whether the DIE for this MDNode can be shared across CUs.
+static bool isShareableAcrossCUs(const DINode *D) {
+ // When the MDNode can be part of the type system, the DIE can be shared
+ // across CUs.
+ // Combining type units and cross-CU DIE sharing is lower value (since
+ // cross-CU DIE sharing is used in LTO and removes type redundancy at that
+ // level already) but may be implementable for some value in projects
+ // building multiple independent libraries with LTO and then linking those
+ // together.
+ return (isa<DIType>(D) ||
+ (isa<DISubprogram>(D) && !cast<DISubprogram>(D)->isDefinition())) &&
+ !GenerateDwarfTypeUnits;
+}
+
+DIE *DwarfUnit::getDIE(const DINode *D) const {
+ if (isShareableAcrossCUs(D))
+ return DU->getDIE(D);
+ return MDNodeToDieMap.lookup(D);
+}
+
+void DwarfUnit::insertDIE(const DINode *Desc, DIE *D) {
+ if (isShareableAcrossCUs(Desc)) {
+ DU->insertDIE(Desc, D);
+ return;
+ }
+ MDNodeToDieMap.insert(std::make_pair(Desc, D));
+}
+
+void DwarfUnit::addFlag(DIE &Die, dwarf::Attribute Attribute) {
+ if (DD->getDwarfVersion() >= 4)
+ Die.addValue(Attribute, dwarf::DW_FORM_flag_present, DIEInteger(1));
+ else
+ Die.addValue(Attribute, dwarf::DW_FORM_flag, DIEInteger(1));
+}
+
+void DwarfUnit::addUInt(DIE &Die, dwarf::Attribute Attribute,
+ Optional<dwarf::Form> Form, uint64_t Integer) {
+ if (!Form)
+ Form = DIEInteger::BestForm(false, Integer);
+ Die.addValue(Attribute, *Form, DIEInteger(Integer));
+}
+
+void DwarfUnit::addUInt(DIE &Block, dwarf::Form Form, uint64_t Integer) {
+ addUInt(Block, (dwarf::Attribute)0, Form, Integer);
+}
+
+void DwarfUnit::addSInt(DIE &Die, dwarf::Attribute Attribute,
+ Optional<dwarf::Form> Form, int64_t Integer) {
+ if (!Form)
+ Form = DIEInteger::BestForm(true, Integer);
+ Die.addValue(Attribute, *Form, DIEInteger(Integer));
+}
+
+void DwarfUnit::addSInt(DIELoc &Die, Optional<dwarf::Form> Form,
+ int64_t Integer) {
+ addSInt(Die, (dwarf::Attribute)0, Form, Integer);
+}
+
+void DwarfUnit::addString(DIE &Die, dwarf::Attribute Attribute,
+ StringRef String) {
+ Die.addValue(Attribute,
+ isDwoUnit() ? dwarf::DW_FORM_GNU_str_index : dwarf::DW_FORM_strp,
+ DIEString(DU->getStringPool().getEntry(*Asm, String)));
+}
+
+void DwarfUnit::addLabel(DIE &Die, dwarf::Attribute Attribute, dwarf::Form Form,
+ const MCSymbol *Label) {
+ Die.addValue(Attribute, Form, DIELabel(Label));
+}
+
+void DwarfUnit::addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label) {
+ addLabel(Die, (dwarf::Attribute)0, Form, Label);
+}
+
+void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
+ uint64_t Integer) {
+ if (DD->getDwarfVersion() >= 4)
+ addUInt(Die, Attribute, dwarf::DW_FORM_sec_offset, Integer);
+ else
+ addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
+}
+
+unsigned DwarfTypeUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
+ return SplitLineTable ? SplitLineTable->getFile(DirName, FileName)
+ : getCU().getOrCreateSourceID(FileName, DirName);
+}
+
+void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) {
+ if (!DD->useSplitDwarf()) {
+ addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
+ addLabel(Die, dwarf::DW_FORM_udata, Sym);
+ } else {
+ addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_addr_index);
+ addUInt(Die, dwarf::DW_FORM_GNU_addr_index,
+ DD->getAddressPool().getIndex(Sym));
+ }
+}
+
+void DwarfUnit::addLabelDelta(DIE &Die, dwarf::Attribute Attribute,
+ const MCSymbol *Hi, const MCSymbol *Lo) {
+ Die.addValue(Attribute, dwarf::DW_FORM_data4,
+ new (DIEValueAllocator) DIEDelta(Hi, Lo));
+}
+
+void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry) {
+ addDIEEntry(Die, Attribute, DIEEntry(Entry));
+}
+
+void DwarfUnit::addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type) {
+ // Flag the type unit reference as a declaration so that if it contains
+ // members (implicit special members, static data member definitions, member
+ // declarations for definitions in this CU, etc) consumers don't get confused
+ // and think this is a full definition.
+ addFlag(Die, dwarf::DW_AT_declaration);
+
+ Die.addValue(dwarf::DW_AT_signature, dwarf::DW_FORM_ref_sig8,
+ DIETypeSignature(Type));
+}
+
+void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
+ DIEEntry Entry) {
+ const DIE *DieCU = Die.getUnitOrNull();
+ const DIE *EntryCU = Entry.getEntry().getUnitOrNull();
+ if (!DieCU)
+ // We assume that Die belongs to this CU, if it is not linked to any CU yet.
+ DieCU = &getUnitDie();
+ if (!EntryCU)
+ EntryCU = &getUnitDie();
+ Die.addValue(Attribute,
+ EntryCU == DieCU ? dwarf::DW_FORM_ref4 : dwarf::DW_FORM_ref_addr,
+ Entry);
+}
+
+DIE &DwarfUnit::createAndAddDIE(unsigned Tag, DIE &Parent, const DINode *N) {
+ assert(Tag != dwarf::DW_TAG_auto_variable &&
+ Tag != dwarf::DW_TAG_arg_variable);
+ DIE &Die = Parent.addChild(make_unique<DIE>((dwarf::Tag)Tag));
+ if (N)
+ insertDIE(N, &Die);
+ return Die;
+}
+
+void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Loc) {
+ Loc->ComputeSize(Asm);
+ DIELocs.push_back(Loc); // Memoize so we can call the destructor later on.
+ Die.addValue(Attribute, Loc->BestForm(DD->getDwarfVersion()), Loc);
+}
+
+void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute,
+ DIEBlock *Block) {
+ Block->ComputeSize(Asm);
+ DIEBlocks.push_back(Block); // Memoize so we can call the destructor later on.
+ Die.addValue(Attribute, Block->BestForm(), Block);
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, StringRef File,
+ StringRef Directory) {
+ if (Line == 0)
+ return;
+
+ unsigned FileID = getOrCreateSourceID(File, Directory);
+ assert(FileID && "Invalid file id");
+ addUInt(Die, dwarf::DW_AT_decl_file, None, FileID);
+ addUInt(Die, dwarf::DW_AT_decl_line, None, Line);
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, const DILocalVariable *V) {
+ assert(V);
+
+ addSourceLine(Die, V->getLine(), V->getScope()->getFilename(),
+ V->getScope()->getDirectory());
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, const DIGlobalVariable *G) {
+ assert(G);
+
+ addSourceLine(Die, G->getLine(), G->getFilename(), G->getDirectory());
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, const DISubprogram *SP) {
+ assert(SP);
+
+ addSourceLine(Die, SP->getLine(), SP->getFilename(), SP->getDirectory());
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, const DIType *Ty) {
+ assert(Ty);
+
+ addSourceLine(Die, Ty->getLine(), Ty->getFilename(), Ty->getDirectory());
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, const DIObjCProperty *Ty) {
+ assert(Ty);
+
+ addSourceLine(Die, Ty->getLine(), Ty->getFilename(), Ty->getDirectory());
+}
+
+void DwarfUnit::addSourceLine(DIE &Die, const DINamespace *NS) {
+ addSourceLine(Die, NS->getLine(), NS->getFilename(), NS->getDirectory());
+}
+
+bool DwarfUnit::addRegisterOpPiece(DIELoc &TheDie, unsigned Reg,
+ unsigned SizeInBits, unsigned OffsetInBits) {
+ DIEDwarfExpression Expr(*Asm, *this, TheDie);
+ Expr.AddMachineRegPiece(Reg, SizeInBits, OffsetInBits);
+ return true;
+}
+
+bool DwarfUnit::addRegisterOffset(DIELoc &TheDie, unsigned Reg,
+ int64_t Offset) {
+ DIEDwarfExpression Expr(*Asm, *this, TheDie);
+ return Expr.AddMachineRegIndirect(Reg, Offset);
+}
+
+/* Byref variables, in Blocks, are declared by the programmer as "SomeType
+ VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
+ gives the variable VarName either the struct, or a pointer to the struct, as
+ its type. This is necessary for various behind-the-scenes things the
+ compiler needs to do with by-reference variables in Blocks.
+
+ However, as far as the original *programmer* is concerned, the variable
+ should still have type 'SomeType', as originally declared.
+
+ The function getBlockByrefType dives into the __Block_byref_x_VarName
+ struct to find the original type of the variable, which is then assigned to
+ the variable's Debug Information Entry as its real type. So far, so good.
+ However now the debugger will expect the variable VarName to have the type
+ SomeType. So we need the location attribute for the variable to be an
+ expression that explains to the debugger how to navigate through the
+ pointers and struct to find the actual variable of type SomeType.
+
+ The following function does just that. We start by getting
+ the "normal" location for the variable. This will be the location
+ of either the struct __Block_byref_x_VarName or the pointer to the
+ struct __Block_byref_x_VarName.
+
+ The struct will look something like:
+
+ struct __Block_byref_x_VarName {
+ ... <various fields>
+ struct __Block_byref_x_VarName *forwarding;
+ ... <various other fields>
+ SomeType VarName;
+ ... <maybe more fields>
+ };
+
+ If we are given the struct directly (as our starting point) we
+ need to tell the debugger to:
+
+ 1). Add the offset of the forwarding field.
+
+ 2). Follow that pointer to get the real __Block_byref_x_VarName
+ struct to use (the real one may have been copied onto the heap).
+
+ 3). Add the offset for the field VarName, to find the actual variable.
+
+ If we started with a pointer to the struct, then we need to
+ dereference that pointer first, before the other steps.
+ Translating this into DWARF ops, we will need to append the following
+ to the current location description for the variable:
+
+ DW_OP_deref -- optional, if we start with a pointer
+ DW_OP_plus_uconst <forward_fld_offset>
+ DW_OP_deref
+ DW_OP_plus_uconst <varName_fld_offset>
+
+ That is what this function does. */
+
+void DwarfUnit::addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
+ dwarf::Attribute Attribute,
+ const MachineLocation &Location) {
+ const DIType *Ty = DV.getType();
+ const DIType *TmpTy = Ty;
+ uint16_t Tag = Ty->getTag();
+ bool isPointer = false;
+
+ StringRef varName = DV.getName();
+
+ if (Tag == dwarf::DW_TAG_pointer_type) {
+ auto *DTy = cast<DIDerivedType>(Ty);
+ TmpTy = resolve(DTy->getBaseType());
+ isPointer = true;
+ }
+
+ // Find the __forwarding field and the variable field in the __Block_byref
+ // struct.
+ DINodeArray Fields = cast<DICompositeTypeBase>(TmpTy)->getElements();
+ const DIDerivedType *varField = nullptr;
+ const DIDerivedType *forwardingField = nullptr;
+
+ for (unsigned i = 0, N = Fields.size(); i < N; ++i) {
+ auto *DT = cast<DIDerivedType>(Fields[i]);
+ StringRef fieldName = DT->getName();
+ if (fieldName == "__forwarding")
+ forwardingField = DT;
+ else if (fieldName == varName)
+ varField = DT;
+ }
+
+ // Get the offsets for the forwarding field and the variable field.
+ unsigned forwardingFieldOffset = forwardingField->getOffsetInBits() >> 3;
+ unsigned varFieldOffset = varField->getOffsetInBits() >> 2;
+
+ // Decode the original location, and use that as the start of the byref
+ // variable's location.
+ DIELoc *Loc = new (DIEValueAllocator) DIELoc;
+
+ bool validReg;
+ if (Location.isReg())
+ validReg = addRegisterOpPiece(*Loc, Location.getReg());
+ else
+ validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
+
+ if (!validReg)
+ return;
+
+ // If we started with a pointer to the __Block_byref... struct, then
+ // the first thing we need to do is dereference the pointer (DW_OP_deref).
+ if (isPointer)
+ addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+
+ // Next add the offset for the '__forwarding' field:
+ // DW_OP_plus_uconst ForwardingFieldOffset. Note there's no point in
+ // adding the offset if it's 0.
+ if (forwardingFieldOffset > 0) {
+ addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+ addUInt(*Loc, dwarf::DW_FORM_udata, forwardingFieldOffset);
+ }
+
+ // Now dereference the __forwarding field to get to the real __Block_byref
+ // struct: DW_OP_deref.
+ addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+
+ // Now that we've got the real __Block_byref... struct, add the offset
+ // for the variable's field to get to the location of the actual variable:
+ // DW_OP_plus_uconst varFieldOffset. Again, don't add if it's 0.
+ if (varFieldOffset > 0) {
+ addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+ addUInt(*Loc, dwarf::DW_FORM_udata, varFieldOffset);
+ }
+
+ // Now attach the location information to the DIE.
+ addBlock(Die, Attribute, Loc);
+}
+
+/// Return true if type encoding is unsigned.
+static bool isUnsignedDIType(DwarfDebug *DD, const DIType *Ty) {
+ if (auto *DTy = dyn_cast<DIDerivedTypeBase>(Ty)) {
+ dwarf::Tag T = (dwarf::Tag)Ty->getTag();
+ // Encode pointer constants as unsigned bytes. This is used at least for
+ // null pointer constant emission.
+ // (Pieces of) aggregate types that get hacked apart by SROA may also be
+ // represented by a constant. Encode them as unsigned bytes.
+ // FIXME: reference and rvalue_reference /probably/ shouldn't be allowed
+ // here, but accept them for now due to a bug in SROA producing bogus
+ // dbg.values.
+ if (T == dwarf::DW_TAG_array_type ||
+ T == dwarf::DW_TAG_class_type ||
+ T == dwarf::DW_TAG_pointer_type ||
+ T == dwarf::DW_TAG_ptr_to_member_type ||
+ T == dwarf::DW_TAG_reference_type ||
+ T == dwarf::DW_TAG_rvalue_reference_type ||
+ T == dwarf::DW_TAG_structure_type ||
+ T == dwarf::DW_TAG_union_type)
+ return true;
+ assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
+ T == dwarf::DW_TAG_volatile_type ||
+ T == dwarf::DW_TAG_restrict_type ||
+ T == dwarf::DW_TAG_enumeration_type);
+ if (DITypeRef Deriv = DTy->getBaseType())
+ return isUnsignedDIType(DD, DD->resolve(Deriv));
+ // FIXME: Enums without a fixed underlying type have unknown signedness
+ // here, leading to incorrectly emitted constants.
+ assert(DTy->getTag() == dwarf::DW_TAG_enumeration_type);
+ return false;
+ }
+
+ auto *BTy = cast<DIBasicType>(Ty);
+ unsigned Encoding = BTy->getEncoding();
+ assert((Encoding == dwarf::DW_ATE_unsigned ||
+ Encoding == dwarf::DW_ATE_unsigned_char ||
+ Encoding == dwarf::DW_ATE_signed ||
+ Encoding == dwarf::DW_ATE_signed_char ||
+ Encoding == dwarf::DW_ATE_float || Encoding == dwarf::DW_ATE_UTF ||
+ Encoding == dwarf::DW_ATE_boolean ||
+ (Ty->getTag() == dwarf::DW_TAG_unspecified_type &&
+ Ty->getName() == "decltype(nullptr)")) &&
+ "Unsupported encoding");
+ return Encoding == dwarf::DW_ATE_unsigned ||
+ Encoding == dwarf::DW_ATE_unsigned_char ||
+ Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean ||
+ Ty->getTag() == dwarf::DW_TAG_unspecified_type;
+}
+
+/// If this type is derived from a base type then return base type size.
+static uint64_t getBaseTypeSize(DwarfDebug *DD, const DIDerivedType *Ty) {
+ unsigned Tag = Ty->getTag();
+
+ if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
+ Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
+ Tag != dwarf::DW_TAG_restrict_type)
+ return Ty->getSizeInBits();
+
+ auto *BaseType = DD->resolve(Ty->getBaseType());
+
+ assert(BaseType && "Unexpected invalid base type");
+
+ // If this is a derived type, go ahead and get the base type, unless it's a
+ // reference then it's just the size of the field. Pointer types have no need
+ // of this since they're a different type of qualification on the type.
+ if (BaseType->getTag() == dwarf::DW_TAG_reference_type ||
+ BaseType->getTag() == dwarf::DW_TAG_rvalue_reference_type)
+ return Ty->getSizeInBits();
+
+ if (auto *DT = dyn_cast<DIDerivedType>(BaseType))
+ return getBaseTypeSize(DD, DT);
+
+ return BaseType->getSizeInBits();
+}
+
+void DwarfUnit::addConstantFPValue(DIE &Die, const MachineOperand &MO) {
+ assert(MO.isFPImm() && "Invalid machine operand!");
+ DIEBlock *Block = new (DIEValueAllocator) DIEBlock;
+ APFloat FPImm = MO.getFPImm()->getValueAPF();
+
+ // Get the raw data form of the floating point.
+ const APInt FltVal = FPImm.bitcastToAPInt();
+ const char *FltPtr = (const char *)FltVal.getRawData();
+
+ int NumBytes = FltVal.getBitWidth() / 8; // 8 bits per byte.
+ bool LittleEndian = Asm->getDataLayout().isLittleEndian();
+ int Incr = (LittleEndian ? 1 : -1);
+ int Start = (LittleEndian ? 0 : NumBytes - 1);
+ int Stop = (LittleEndian ? NumBytes : -1);
+
+ // Output the constant to DWARF one byte at a time.
+ for (; Start != Stop; Start += Incr)
+ addUInt(*Block, dwarf::DW_FORM_data1, (unsigned char)0xFF & FltPtr[Start]);
+
+ addBlock(Die, dwarf::DW_AT_const_value, Block);
+}
+
+void DwarfUnit::addConstantFPValue(DIE &Die, const ConstantFP *CFP) {
+ // Pass this down to addConstantValue as an unsigned bag of bits.
+ addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
+}
+
+void DwarfUnit::addConstantValue(DIE &Die, const ConstantInt *CI,
+ const DIType *Ty) {
+ addConstantValue(Die, CI->getValue(), Ty);
+}
+
+void DwarfUnit::addConstantValue(DIE &Die, const MachineOperand &MO,
+ const DIType *Ty) {
+ assert(MO.isImm() && "Invalid machine operand!");
+
+ addConstantValue(Die, isUnsignedDIType(DD, Ty), MO.getImm());
+}
+
+void DwarfUnit::addConstantValue(DIE &Die, bool Unsigned, uint64_t Val) {
+ // FIXME: This is a bit conservative/simple - it emits negative values always
+ // sign extended to 64 bits rather than minimizing the number of bytes.
+ addUInt(Die, dwarf::DW_AT_const_value,
+ Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata, Val);
+}
+
+void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, const DIType *Ty) {
+ addConstantValue(Die, Val, isUnsignedDIType(DD, Ty));
+}
+
+void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
+ unsigned CIBitWidth = Val.getBitWidth();
+ if (CIBitWidth <= 64) {
+ addConstantValue(Die, Unsigned,
+ Unsigned ? Val.getZExtValue() : Val.getSExtValue());
+ return;
+ }
+
+ DIEBlock *Block = new (DIEValueAllocator) DIEBlock;
+
+ // Get the raw data form of the large APInt.
+ const uint64_t *Ptr64 = Val.getRawData();
+
+ int NumBytes = Val.getBitWidth() / 8; // 8 bits per byte.
+ bool LittleEndian = Asm->getDataLayout().isLittleEndian();
+
+ // Output the constant to DWARF one byte at a time.
+ for (int i = 0; i < NumBytes; i++) {
+ uint8_t c;
+ if (LittleEndian)
+ c = Ptr64[i / 8] >> (8 * (i & 7));
+ else
+ c = Ptr64[(NumBytes - 1 - i) / 8] >> (8 * ((NumBytes - 1 - i) & 7));
+ addUInt(*Block, dwarf::DW_FORM_data1, c);
+ }
+
+ addBlock(Die, dwarf::DW_AT_const_value, Block);
+}
+
+void DwarfUnit::addLinkageName(DIE &Die, StringRef LinkageName) {
+ if (!LinkageName.empty())
+ addString(Die,
+ DD->getDwarfVersion() >= 4 ? dwarf::DW_AT_linkage_name
+ : dwarf::DW_AT_MIPS_linkage_name,
+ GlobalValue::getRealLinkageName(LinkageName));
+}
+
+void DwarfUnit::addTemplateParams(DIE &Buffer, DINodeArray TParams) {
+ // Add template parameters.
+ for (const auto *Element : TParams) {
+ if (auto *TTP = dyn_cast<DITemplateTypeParameter>(Element))
+ constructTemplateTypeParameterDIE(Buffer, TTP);
+ else if (auto *TVP = dyn_cast<DITemplateValueParameter>(Element))
+ constructTemplateValueParameterDIE(Buffer, TVP);
+ }
+}
+
+DIE *DwarfUnit::getOrCreateContextDIE(const DIScope *Context) {
+ if (!Context || isa<DIFile>(Context))
+ return &getUnitDie();
+ if (auto *T = dyn_cast<DIType>(Context))
+ return getOrCreateTypeDIE(T);
+ if (auto *NS = dyn_cast<DINamespace>(Context))
+ return getOrCreateNameSpace(NS);
+ if (auto *SP = dyn_cast<DISubprogram>(Context))
+ return getOrCreateSubprogramDIE(SP);
+ return getDIE(Context);
+}
+
+DIE *DwarfUnit::createTypeDIE(const DICompositeType *Ty) {
+ auto *Context = resolve(Ty->getScope());
+ DIE *ContextDIE = getOrCreateContextDIE(Context);
+
+ if (DIE *TyDIE = getDIE(Ty))
+ return TyDIE;
+
+ // Create new type.
+ DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
+
+ constructTypeDIE(TyDIE, cast<DICompositeType>(Ty));
+
+ updateAcceleratorTables(Context, Ty, TyDIE);
+ return &TyDIE;
+}
+
+DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
+ if (!TyNode)
+ return nullptr;
+
+ auto *Ty = cast<DIType>(TyNode);
+ assert(Ty == resolve(Ty->getRef()) &&
+ "type was not uniqued, possible ODR violation.");
+
+ // DW_TAG_restrict_type is not supported in DWARF2
+ if (Ty->getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
+ return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()));
+
+ // Construct the context before querying for the existence of the DIE in case
+ // such construction creates the DIE.
+ auto *Context = resolve(Ty->getScope());
+ DIE *ContextDIE = getOrCreateContextDIE(Context);
+ assert(ContextDIE);
+
+ if (DIE *TyDIE = getDIE(Ty))
+ return TyDIE;
+
+ // Create new type.
+ DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
+
+ updateAcceleratorTables(Context, Ty, TyDIE);
+
+ if (auto *BT = dyn_cast<DIBasicType>(Ty))
+ constructTypeDIE(TyDIE, BT);
+ else if (auto *STy = dyn_cast<DISubroutineType>(Ty))
+ constructTypeDIE(TyDIE, STy);
+ else if (auto *CTy = dyn_cast<DICompositeType>(Ty)) {
+ if (GenerateDwarfTypeUnits && !Ty->isForwardDecl())
+ if (MDString *TypeId = CTy->getRawIdentifier()) {
+ DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);
+ // Skip updating the accelerator tables since this is not the full type.
+ return &TyDIE;
+ }
+ constructTypeDIE(TyDIE, CTy);
+ } else {
+ constructTypeDIE(TyDIE, cast<DIDerivedType>(Ty));
+ }
+
+ return &TyDIE;
+}
+
+void DwarfUnit::updateAcceleratorTables(const DIScope *Context,
+ const DIType *Ty, const DIE &TyDIE) {
+ if (!Ty->getName().empty() && !Ty->isForwardDecl()) {
+ bool IsImplementation = 0;
+ if (auto *CT = dyn_cast<DICompositeTypeBase>(Ty)) {
+ // A runtime language of 0 actually means C/C++ and that any
+ // non-negative value is some version of Objective-C/C++.
+ IsImplementation = CT->getRuntimeLang() == 0 || CT->isObjcClassComplete();
+ }
+ unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
+ DD->addAccelType(Ty->getName(), TyDIE, Flags);
+
+ if (!Context || isa<DICompileUnit>(Context) || isa<DIFile>(Context) ||
+ isa<DINamespace>(Context))
+ addGlobalType(Ty, TyDIE, Context);
+ }
+}
+
+void DwarfUnit::addType(DIE &Entity, const DIType *Ty,
+ dwarf::Attribute Attribute) {
+ assert(Ty && "Trying to add a type that doesn't exist?");
+ addDIEEntry(Entity, Attribute, DIEEntry(*getOrCreateTypeDIE(Ty)));
+}
+
+std::string DwarfUnit::getParentContextString(const DIScope *Context) const {
+ if (!Context)
+ return "";
+
+ // FIXME: Decide whether to implement this for non-C++ languages.
+ if (getLanguage() != dwarf::DW_LANG_C_plus_plus)
+ return "";
+
+ std::string CS;
+ SmallVector<const DIScope *, 1> Parents;
+ while (!isa<DICompileUnit>(Context)) {
+ Parents.push_back(Context);
+ if (Context->getScope())
+ Context = resolve(Context->getScope());
+ else
+ // Structure, etc types will have a NULL context if they're at the top
+ // level.
+ break;
+ }
+
+ // Reverse iterate over our list to go from the outermost construct to the
+ // innermost.
+ for (auto I = Parents.rbegin(), E = Parents.rend(); I != E; ++I) {
+ const DIScope *Ctx = *I;
+ StringRef Name = Ctx->getName();
+ if (Name.empty() && isa<DINamespace>(Ctx))
+ Name = "(anonymous namespace)";
+ if (!Name.empty()) {
+ CS += Name;
+ CS += "::";
+ }
+ }
+ return CS;
+}
+
+void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIBasicType *BTy) {
+ // Get core information.
+ StringRef Name = BTy->getName();
+ // Add name if not anonymous or intermediate type.
+ if (!Name.empty())
+ addString(Buffer, dwarf::DW_AT_name, Name);
+
+ // An unspecified type only has a name attribute.
+ if (BTy->getTag() == dwarf::DW_TAG_unspecified_type)
+ return;
+
+ addUInt(Buffer, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
+ BTy->getEncoding());
+
+ uint64_t Size = BTy->getSizeInBits() >> 3;
+ addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
+}
+
+void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy) {
+ // Get core information.
+ StringRef Name = DTy->getName();
+ uint64_t Size = DTy->getSizeInBits() >> 3;
+ uint16_t Tag = Buffer.getTag();
+
+ // Map to main type, void will not have a type.
+ const DIType *FromTy = resolve(DTy->getBaseType());
+ if (FromTy)
+ addType(Buffer, FromTy);
+
+ // Add name if not anonymous or intermediate type.
+ if (!Name.empty())
+ addString(Buffer, dwarf::DW_AT_name, Name);
+
+ // Add size if non-zero (derived types might be zero-sized.)
+ if (Size && Tag != dwarf::DW_TAG_pointer_type
+ && Tag != dwarf::DW_TAG_ptr_to_member_type)
+ addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
+
+ if (Tag == dwarf::DW_TAG_ptr_to_member_type)
+ addDIEEntry(
+ Buffer, dwarf::DW_AT_containing_type,
+ *getOrCreateTypeDIE(resolve(cast<DIDerivedType>(DTy)->getClassType())));
+ // Add source line info if available and TyDesc is not a forward declaration.
+ if (!DTy->isForwardDecl())
+ addSourceLine(Buffer, DTy);
+}
+
+void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DITypeRefArray Args) {
+ for (unsigned i = 1, N = Args.size(); i < N; ++i) {
+ const DIType *Ty = resolve(Args[i]);
+ if (!Ty) {
+ assert(i == N-1 && "Unspecified parameter must be the last argument");
+ createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
+ } else {
+ DIE &Arg = createAndAddDIE(dwarf::DW_TAG_formal_parameter, Buffer);
+ addType(Arg, Ty);
+ if (Ty->isArtificial())
+ addFlag(Arg, dwarf::DW_AT_artificial);
+ }
+ }
+}
+
+void DwarfUnit::constructTypeDIE(DIE &Buffer, const DISubroutineType *CTy) {
+ // Add return type. A void return won't have a type.
+ auto Elements = cast<DISubroutineType>(CTy)->getTypeArray();
+ if (Elements.size())
+ if (auto RTy = resolve(Elements[0]))
+ addType(Buffer, RTy);
+
+ bool isPrototyped = true;
+ if (Elements.size() == 2 && !Elements[1])
+ isPrototyped = false;
+
+ constructSubprogramArguments(Buffer, Elements);
+
+ // Add prototype flag if we're dealing with a C language and the function has
+ // been prototyped.
+ uint16_t Language = getLanguage();
+ if (isPrototyped &&
+ (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
+ Language == dwarf::DW_LANG_ObjC))
+ addFlag(Buffer, dwarf::DW_AT_prototyped);
+
+ if (CTy->isLValueReference())
+ addFlag(Buffer, dwarf::DW_AT_reference);
+
+ if (CTy->isRValueReference())
+ addFlag(Buffer, dwarf::DW_AT_rvalue_reference);
+}
+
+void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
+ // Add name if not anonymous or intermediate type.
+ StringRef Name = CTy->getName();
+
+ uint64_t Size = CTy->getSizeInBits() >> 3;
+ uint16_t Tag = Buffer.getTag();
+
+ switch (Tag) {
+ case dwarf::DW_TAG_array_type:
+ constructArrayTypeDIE(Buffer, CTy);
+ break;
+ case dwarf::DW_TAG_enumeration_type:
+ constructEnumTypeDIE(Buffer, CTy);
+ break;
+ case dwarf::DW_TAG_structure_type:
+ case dwarf::DW_TAG_union_type:
+ case dwarf::DW_TAG_class_type: {
+ // Add elements to structure type.
+ DINodeArray Elements = CTy->getElements();
+ for (const auto *Element : Elements) {
+ if (!Element)
+ continue;
+ if (auto *SP = dyn_cast<DISubprogram>(Element))
+ getOrCreateSubprogramDIE(SP);
+ else if (auto *DDTy = dyn_cast<DIDerivedType>(Element)) {
+ if (DDTy->getTag() == dwarf::DW_TAG_friend) {
+ DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
+ addType(ElemDie, resolve(DDTy->getBaseType()), dwarf::DW_AT_friend);
+ } else if (DDTy->isStaticMember()) {
+ getOrCreateStaticMemberDIE(DDTy);
+ } else {
+ constructMemberDIE(Buffer, DDTy);
+ }
+ } else if (auto *Property = dyn_cast<DIObjCProperty>(Element)) {
+ DIE &ElemDie = createAndAddDIE(Property->getTag(), Buffer);
+ StringRef PropertyName = Property->getName();
+ addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
+ if (Property->getType())
+ addType(ElemDie, resolve(Property->getType()));
+ addSourceLine(ElemDie, Property);
+ StringRef GetterName = Property->getGetterName();
+ if (!GetterName.empty())
+ addString(ElemDie, dwarf::DW_AT_APPLE_property_getter, GetterName);
+ StringRef SetterName = Property->getSetterName();
+ if (!SetterName.empty())
+ addString(ElemDie, dwarf::DW_AT_APPLE_property_setter, SetterName);
+ if (unsigned PropertyAttributes = Property->getAttributes())
+ addUInt(ElemDie, dwarf::DW_AT_APPLE_property_attribute, None,
+ PropertyAttributes);
+ }
+ }
+
+ if (CTy->isAppleBlockExtension())
+ addFlag(Buffer, dwarf::DW_AT_APPLE_block);
+
+ // This is outside the DWARF spec, but GDB expects a DW_AT_containing_type
+ // inside C++ composite types to point to the base class with the vtable.
+ if (auto *ContainingType =
+ dyn_cast_or_null<DICompositeType>(resolve(CTy->getVTableHolder())))
+ addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
+ *getOrCreateTypeDIE(ContainingType));
+
+ if (CTy->isObjcClassComplete())
+ addFlag(Buffer, dwarf::DW_AT_APPLE_objc_complete_type);
+
+ // Add template parameters to a class, structure or union types.
+ // FIXME: The support isn't in the metadata for this yet.
+ if (Tag == dwarf::DW_TAG_class_type ||
+ Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
+ addTemplateParams(Buffer, CTy->getTemplateParams());
+
+ break;
+ }
+ default:
+ break;
+ }
+
+ // Add name if not anonymous or intermediate type.
+ if (!Name.empty())
+ addString(Buffer, dwarf::DW_AT_name, Name);
+
+ if (Tag == dwarf::DW_TAG_enumeration_type ||
+ Tag == dwarf::DW_TAG_class_type || Tag == dwarf::DW_TAG_structure_type ||
+ Tag == dwarf::DW_TAG_union_type) {
+ // Add size if non-zero (derived types might be zero-sized.)
+ // TODO: Do we care about size for enum forward declarations?
+ if (Size)
+ addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
+ else if (!CTy->isForwardDecl())
+ // Add zero size if it is not a forward declaration.
+ addUInt(Buffer, dwarf::DW_AT_byte_size, None, 0);
+
+ // If we're a forward decl, say so.
+ if (CTy->isForwardDecl())
+ addFlag(Buffer, dwarf::DW_AT_declaration);
+
+ // Add source line info if available.
+ if (!CTy->isForwardDecl())
+ addSourceLine(Buffer, CTy);
+
+ // No harm in adding the runtime language to the declaration.
+ unsigned RLang = CTy->getRuntimeLang();
+ if (RLang)
+ addUInt(Buffer, dwarf::DW_AT_APPLE_runtime_class, dwarf::DW_FORM_data1,
+ RLang);
+ }
+}
+
+void DwarfUnit::constructTemplateTypeParameterDIE(
+ DIE &Buffer, const DITemplateTypeParameter *TP) {
+ DIE &ParamDIE =
+ createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
+ // Add the type if it exists, it could be void and therefore no type.
+ if (TP->getType())
+ addType(ParamDIE, resolve(TP->getType()));
+ if (!TP->getName().empty())
+ addString(ParamDIE, dwarf::DW_AT_name, TP->getName());
+}
+
+void DwarfUnit::constructTemplateValueParameterDIE(
+ DIE &Buffer, const DITemplateValueParameter *VP) {
+ DIE &ParamDIE = createAndAddDIE(VP->getTag(), Buffer);
+
+ // Add the type if there is one, template template and template parameter
+ // packs will not have a type.
+ if (VP->getTag() == dwarf::DW_TAG_template_value_parameter)
+ addType(ParamDIE, resolve(VP->getType()));
+ if (!VP->getName().empty())
+ addString(ParamDIE, dwarf::DW_AT_name, VP->getName());
+ if (Metadata *Val = VP->getValue()) {
+ if (ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(Val))
+ addConstantValue(ParamDIE, CI, resolve(VP->getType()));
+ else if (GlobalValue *GV = mdconst::dyn_extract<GlobalValue>(Val)) {
+ // For declaration non-type template parameters (such as global values and
+ // functions)
+ DIELoc *Loc = new (DIEValueAllocator) DIELoc;
+ addOpAddress(*Loc, Asm->getSymbol(GV));
+ // Emit DW_OP_stack_value to use the address as the immediate value of the
+ // parameter, rather than a pointer to it.
+ addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_stack_value);
+ addBlock(ParamDIE, dwarf::DW_AT_location, Loc);
+ } else if (VP->getTag() == dwarf::DW_TAG_GNU_template_template_param) {
+ assert(isa<MDString>(Val));
+ addString(ParamDIE, dwarf::DW_AT_GNU_template_name,
+ cast<MDString>(Val)->getString());
+ } else if (VP->getTag() == dwarf::DW_TAG_GNU_template_parameter_pack) {
+ addTemplateParams(ParamDIE, cast<MDTuple>(Val));
+ }
+ }
+}
+
+DIE *DwarfUnit::getOrCreateNameSpace(const DINamespace *NS) {
+ // Construct the context before querying for the existence of the DIE in case
+ // such construction creates the DIE.
+ DIE *ContextDIE = getOrCreateContextDIE(NS->getScope());
+
+ if (DIE *NDie = getDIE(NS))
+ return NDie;
+ DIE &NDie = createAndAddDIE(dwarf::DW_TAG_namespace, *ContextDIE, NS);
+
+ StringRef Name = NS->getName();
+ if (!Name.empty())
+ addString(NDie, dwarf::DW_AT_name, NS->getName());
+ else
+ Name = "(anonymous namespace)";
+ DD->addAccelNamespace(Name, NDie);
+ addGlobalName(Name, NDie, NS->getScope());
+ addSourceLine(NDie, NS);
+ return &NDie;
+}
+
+DIE *DwarfUnit::getOrCreateSubprogramDIE(const DISubprogram *SP, bool Minimal) {
+ // Construct the context before querying for the existence of the DIE in case
+ // such construction creates the DIE (as is the case for member function
+ // declarations).
+ DIE *ContextDIE =
+ Minimal ? &getUnitDie() : getOrCreateContextDIE(resolve(SP->getScope()));
+
+ if (DIE *SPDie = getDIE(SP))
+ return SPDie;
+
+ if (auto *SPDecl = SP->getDeclaration()) {
+ if (!Minimal) {
+ // Add subprogram definitions to the CU die directly.
+ ContextDIE = &getUnitDie();
+ // Build the decl now to ensure it precedes the definition.
+ getOrCreateSubprogramDIE(SPDecl);
+ }
+ }
+
+ // DW_TAG_inlined_subroutine may refer to this DIE.
+ DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
+
+ // Stop here and fill this in later, depending on whether or not this
+ // subprogram turns out to have inlined instances or not.
+ if (SP->isDefinition())
+ return &SPDie;
+
+ applySubprogramAttributes(SP, SPDie);
+ return &SPDie;
+}
+
+bool DwarfUnit::applySubprogramDefinitionAttributes(const DISubprogram *SP,
+ DIE &SPDie) {
+ DIE *DeclDie = nullptr;
+ StringRef DeclLinkageName;
+ if (auto *SPDecl = SP->getDeclaration()) {
+ DeclDie = getDIE(SPDecl);
+ assert(DeclDie && "This DIE should've already been constructed when the "
+ "definition DIE was created in "
+ "getOrCreateSubprogramDIE");
+ DeclLinkageName = SPDecl->getLinkageName();
+ }
+
+ // Add function template parameters.
+ addTemplateParams(SPDie, SP->getTemplateParams());
+
+ // Add the linkage name if we have one and it isn't in the Decl.
+ StringRef LinkageName = SP->getLinkageName();
+ assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
+ LinkageName == DeclLinkageName) &&
+ "decl has a linkage name and it is different");
+ if (DeclLinkageName.empty())
+ addLinkageName(SPDie, LinkageName);
+
+ if (!DeclDie)
+ return false;
+
+ // Refer to the function declaration where all the other attributes will be
+ // found.
+ addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
+ return true;
+}
+
+void DwarfUnit::applySubprogramAttributes(const DISubprogram *SP, DIE &SPDie,
+ bool Minimal) {
+ if (!Minimal)
+ if (applySubprogramDefinitionAttributes(SP, SPDie))
+ return;
+
+ // Constructors and operators for anonymous aggregates do not have names.
+ if (!SP->getName().empty())
+ addString(SPDie, dwarf::DW_AT_name, SP->getName());
+
+ // Skip the rest of the attributes under -gmlt to save space.
+ if (Minimal)
+ return;
+
+ addSourceLine(SPDie, SP);
+
+ // Add the prototype if we have a prototype and we have a C like
+ // language.
+ uint16_t Language = getLanguage();
+ if (SP->isPrototyped() &&
+ (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
+ Language == dwarf::DW_LANG_ObjC))
+ addFlag(SPDie, dwarf::DW_AT_prototyped);
+
+ const DISubroutineType *SPTy = SP->getType();
+ assert(SPTy->getTag() == dwarf::DW_TAG_subroutine_type &&
+ "the type of a subprogram should be a subroutine");
+
+ auto Args = SPTy->getTypeArray();
+ // Add a return type. If this is a type like a C/C++ void type we don't add a
+ // return type.
+ if (Args.size())
+ if (auto Ty = resolve(Args[0]))
+ addType(SPDie, Ty);
+
+ unsigned VK = SP->getVirtuality();
+ if (VK) {
+ addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1, VK);
+ DIELoc *Block = getDIELoc();
+ addUInt(*Block, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
+ addUInt(*Block, dwarf::DW_FORM_udata, SP->getVirtualIndex());
+ addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
+ ContainingTypeMap.insert(
+ std::make_pair(&SPDie, resolve(SP->getContainingType())));
+ }
+
+ if (!SP->isDefinition()) {
+ addFlag(SPDie, dwarf::DW_AT_declaration);
+
+ // Add arguments. Do not add arguments for subprogram definition. They will
+ // be handled while processing variables.
+ constructSubprogramArguments(SPDie, Args);
+ }
+
+ if (SP->isArtificial())
+ addFlag(SPDie, dwarf::DW_AT_artificial);
+
+ if (!SP->isLocalToUnit())
+ addFlag(SPDie, dwarf::DW_AT_external);
+
+ if (SP->isOptimized())
+ addFlag(SPDie, dwarf::DW_AT_APPLE_optimized);
+
+ if (unsigned isa = Asm->getISAEncoding())
+ addUInt(SPDie, dwarf::DW_AT_APPLE_isa, dwarf::DW_FORM_flag, isa);
+
+ if (SP->isLValueReference())
+ addFlag(SPDie, dwarf::DW_AT_reference);
+
+ if (SP->isRValueReference())
+ addFlag(SPDie, dwarf::DW_AT_rvalue_reference);
+
+ if (SP->isProtected())
+ addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_protected);
+ else if (SP->isPrivate())
+ addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_private);
+ else if (SP->isPublic())
+ addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_public);
+
+ if (SP->isExplicit())
+ addFlag(SPDie, dwarf::DW_AT_explicit);
+}
+
+void DwarfUnit::constructSubrangeDIE(DIE &Buffer, const DISubrange *SR,
+ DIE *IndexTy) {
+ DIE &DW_Subrange = createAndAddDIE(dwarf::DW_TAG_subrange_type, Buffer);
+ addDIEEntry(DW_Subrange, dwarf::DW_AT_type, *IndexTy);
+
+ // The LowerBound value defines the lower bounds which is typically zero for
+ // C/C++. The Count value is the number of elements. Values are 64 bit. If
+ // Count == -1 then the array is unbounded and we do not emit
+ // DW_AT_lower_bound and DW_AT_count attributes.
+ int64_t LowerBound = SR->getLowerBound();
+ int64_t DefaultLowerBound = getDefaultLowerBound();
+ int64_t Count = SR->getCount();
+
+ if (DefaultLowerBound == -1 || LowerBound != DefaultLowerBound)
+ addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, None, LowerBound);
+
+ if (Count != -1)
+ // FIXME: An unbounded array should reference the expression that defines
+ // the array.
+ addUInt(DW_Subrange, dwarf::DW_AT_count, None, Count);
+}
+
+DIE *DwarfUnit::getIndexTyDie() {
+ if (IndexTyDie)
+ return IndexTyDie;
+ // Construct an integer type to use for indexes.
+ IndexTyDie = &createAndAddDIE(dwarf::DW_TAG_base_type, UnitDie);
+ addString(*IndexTyDie, dwarf::DW_AT_name, "sizetype");
+ addUInt(*IndexTyDie, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
+ addUInt(*IndexTyDie, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
+ dwarf::DW_ATE_unsigned);
+ return IndexTyDie;
+}
+
+void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
+ if (CTy->isVector())
+ addFlag(Buffer, dwarf::DW_AT_GNU_vector);
+
+ // Emit the element type.
+ addType(Buffer, resolve(CTy->getBaseType()));
+
+ // Get an anonymous type for index type.
+ // FIXME: This type should be passed down from the front end
+ // as different languages may have different sizes for indexes.
+ DIE *IdxTy = getIndexTyDie();
+
+ // Add subranges to array type.
+ DINodeArray Elements = CTy->getElements();
+ for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
+ // FIXME: Should this really be such a loose cast?
+ if (auto *Element = dyn_cast_or_null<DINode>(Elements[i]))
+ if (Element->getTag() == dwarf::DW_TAG_subrange_type)
+ constructSubrangeDIE(Buffer, cast<DISubrange>(Element), IdxTy);
+ }
+}
+
+void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
+ DINodeArray Elements = CTy->getElements();
+
+ // Add enumerators to enumeration type.
+ for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
+ auto *Enum = dyn_cast_or_null<DIEnumerator>(Elements[i]);
+ if (Enum) {
+ DIE &Enumerator = createAndAddDIE(dwarf::DW_TAG_enumerator, Buffer);
+ StringRef Name = Enum->getName();
+ addString(Enumerator, dwarf::DW_AT_name, Name);
+ int64_t Value = Enum->getValue();
+ addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
+ Value);
+ }
+ }
+ const DIType *DTy = resolve(CTy->getBaseType());
+ if (DTy) {
+ addType(Buffer, DTy);
+ addFlag(Buffer, dwarf::DW_AT_enum_class);
+ }
+}
+
+void DwarfUnit::constructContainingTypeDIEs() {
+ for (auto CI = ContainingTypeMap.begin(), CE = ContainingTypeMap.end();
+ CI != CE; ++CI) {
+ DIE &SPDie = *CI->first;
+ const DINode *D = CI->second;
+ if (!D)
+ continue;
+ DIE *NDie = getDIE(D);
+ if (!NDie)
+ continue;
+ addDIEEntry(SPDie, dwarf::DW_AT_containing_type, *NDie);
+ }
+}
+
+void DwarfUnit::constructMemberDIE(DIE &Buffer, const DIDerivedType *DT) {
+ DIE &MemberDie = createAndAddDIE(DT->getTag(), Buffer);
+ StringRef Name = DT->getName();
+ if (!Name.empty())
+ addString(MemberDie, dwarf::DW_AT_name, Name);
+
+ addType(MemberDie, resolve(DT->getBaseType()));
+
+ addSourceLine(MemberDie, DT);
+
+ if (DT->getTag() == dwarf::DW_TAG_inheritance && DT->isVirtual()) {
+
+ // For C++, virtual base classes are not at fixed offset. Use following
+ // expression to extract appropriate offset from vtable.
+ // BaseAddr = ObAddr + *((*ObAddr) - Offset)
+
+ DIELoc *VBaseLocationDie = new (DIEValueAllocator) DIELoc;
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_udata, DT->getOffsetInBits());
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+ addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
+
+ addBlock(MemberDie, dwarf::DW_AT_data_member_location, VBaseLocationDie);
+ } else {
+ uint64_t Size = DT->getSizeInBits();
+ uint64_t FieldSize = getBaseTypeSize(DD, DT);
+ uint64_t OffsetInBytes;
+
+ if (FieldSize && Size != FieldSize) {
+ // Handle bitfield, assume bytes are 8 bits.
+ addUInt(MemberDie, dwarf::DW_AT_byte_size, None, FieldSize/8);
+ addUInt(MemberDie, dwarf::DW_AT_bit_size, None, Size);
+
+ uint64_t Offset = DT->getOffsetInBits();
+ uint64_t AlignMask = ~(DT->getAlignInBits() - 1);
+ uint64_t HiMark = (Offset + FieldSize) & AlignMask;
+ uint64_t FieldOffset = (HiMark - FieldSize);
+ Offset -= FieldOffset;
+
+ // Maybe we need to work from the other end.
+ if (Asm->getDataLayout().isLittleEndian())
+ Offset = FieldSize - (Offset + Size);
+ addUInt(MemberDie, dwarf::DW_AT_bit_offset, None, Offset);
+
+ // Here DW_AT_data_member_location points to the anonymous
+ // field that includes this bit field.
+ OffsetInBytes = FieldOffset >> 3;
+ } else
+ // This is not a bitfield.
+ OffsetInBytes = DT->getOffsetInBits() >> 3;
+
+ if (DD->getDwarfVersion() <= 2) {
+ DIELoc *MemLocationDie = new (DIEValueAllocator) DIELoc;
+ addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+ addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes);
+ addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie);
+ } else
+ addUInt(MemberDie, dwarf::DW_AT_data_member_location, None,
+ OffsetInBytes);
+ }
+
+ if (DT->isProtected())
+ addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_protected);
+ else if (DT->isPrivate())
+ addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_private);
+ // Otherwise C++ member and base classes are considered public.
+ else if (DT->isPublic())
+ addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_public);
+ if (DT->isVirtual())
+ addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1,
+ dwarf::DW_VIRTUALITY_virtual);
+
+ // Objective-C properties.
+ if (DINode *PNode = DT->getObjCProperty())
+ if (DIE *PDie = getDIE(PNode))
+ MemberDie.addValue(dwarf::DW_AT_APPLE_property, dwarf::DW_FORM_ref4,
+ DIEEntry(*PDie));
+
+ if (DT->isArtificial())
+ addFlag(MemberDie, dwarf::DW_AT_artificial);
+}
+
+DIE *DwarfUnit::getOrCreateStaticMemberDIE(const DIDerivedType *DT) {
+ if (!DT)
+ return nullptr;
+
+ // Construct the context before querying for the existence of the DIE in case
+ // such construction creates the DIE.
+ DIE *ContextDIE = getOrCreateContextDIE(resolve(DT->getScope()));
+ assert(dwarf::isType(ContextDIE->getTag()) &&
+ "Static member should belong to a type.");
+
+ if (DIE *StaticMemberDIE = getDIE(DT))
+ return StaticMemberDIE;
+
+ DIE &StaticMemberDIE = createAndAddDIE(DT->getTag(), *ContextDIE, DT);
+
+ const DIType *Ty = resolve(DT->getBaseType());
+
+ addString(StaticMemberDIE, dwarf::DW_AT_name, DT->getName());
+ addType(StaticMemberDIE, Ty);
+ addSourceLine(StaticMemberDIE, DT);
+ addFlag(StaticMemberDIE, dwarf::DW_AT_external);
+ addFlag(StaticMemberDIE, dwarf::DW_AT_declaration);
+
+ // FIXME: We could omit private if the parent is a class_type, and
+ // public if the parent is something else.
+ if (DT->isProtected())
+ addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_protected);
+ else if (DT->isPrivate())
+ addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_private);
+ else if (DT->isPublic())
+ addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
+ dwarf::DW_ACCESS_public);
+
+ if (const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(DT->getConstant()))
+ addConstantValue(StaticMemberDIE, CI, Ty);
+ if (const ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(DT->getConstant()))
+ addConstantFPValue(StaticMemberDIE, CFP);
+
+ return &StaticMemberDIE;
+}
+
+void DwarfUnit::emitHeader(bool UseOffsets) {
+ // Emit size of content not including length itself
+ Asm->OutStreamer->AddComment("Length of Unit");
+ Asm->EmitInt32(getHeaderSize() + UnitDie.getSize());
+
+ Asm->OutStreamer->AddComment("DWARF version number");
+ Asm->EmitInt16(DD->getDwarfVersion());
+ Asm->OutStreamer->AddComment("Offset Into Abbrev. Section");
+
+ // We share one abbreviations table across all units so it's always at the
+ // start of the section. Use a relocatable offset where needed to ensure
+ // linking doesn't invalidate that offset.
+ const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
+ Asm->emitDwarfSymbolReference(TLOF.getDwarfAbbrevSection()->getBeginSymbol(),
+ UseOffsets);
+
+ Asm->OutStreamer->AddComment("Address Size (in bytes)");
+ Asm->EmitInt8(Asm->getDataLayout().getPointerSize());
+}
+
+void DwarfUnit::initSection(MCSection *Section) {
+ assert(!this->Section);
+ this->Section = Section;
+}
+
+void DwarfTypeUnit::emitHeader(bool UseOffsets) {
+ DwarfUnit::emitHeader(UseOffsets);
+ Asm->OutStreamer->AddComment("Type Signature");
+ Asm->OutStreamer->EmitIntValue(TypeSignature, sizeof(TypeSignature));
+ Asm->OutStreamer->AddComment("Type DIE Offset");
+ // In a skeleton type unit there is no type DIE so emit a zero offset.
+ Asm->OutStreamer->EmitIntValue(Ty ? Ty->getOffset() : 0,
+ sizeof(Ty->getOffset()));
+}
+
+bool DwarfTypeUnit::isDwoUnit() const {
+ // Since there are no skeleton type units, all type units are dwo type units
+ // when split DWARF is being used.
+ return DD->useSplitDwarf();
+}
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