1 //===-- llvm/CodeGen/DwarfUnit.cpp - Dwarf Type and Compile Units ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for constructing a dwarf compile unit.
12 //===----------------------------------------------------------------------===//
14 #include "DwarfUnit.h"
15 #include "DwarfAccelTable.h"
16 #include "DwarfCompileUnit.h"
17 #include "DwarfDebug.h"
18 #include "DwarfExpression.h"
19 #include "llvm/ADT/APFloat.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/DIBuilder.h"
22 #include "llvm/IR/DataLayout.h"
23 #include "llvm/IR/GlobalVariable.h"
24 #include "llvm/IR/Instructions.h"
25 #include "llvm/IR/Mangler.h"
26 #include "llvm/MC/MCAsmInfo.h"
27 #include "llvm/MC/MCContext.h"
28 #include "llvm/MC/MCSection.h"
29 #include "llvm/MC/MCStreamer.h"
30 #include "llvm/Support/CommandLine.h"
31 #include "llvm/Target/TargetFrameLowering.h"
32 #include "llvm/Target/TargetLoweringObjectFile.h"
33 #include "llvm/Target/TargetMachine.h"
34 #include "llvm/Target/TargetRegisterInfo.h"
35 #include "llvm/Target/TargetSubtargetInfo.h"
39 #define DEBUG_TYPE "dwarfdebug"
42 GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
43 cl::desc("Generate DWARF4 type units."),
46 void DIEDwarfExpression::EmitOp(uint8_t Op, const char* Comment) {
47 DU.addUInt(DIE, dwarf::DW_FORM_data1, Op);
49 void DIEDwarfExpression::EmitSigned(int Value) {
50 DU.addSInt(DIE, dwarf::DW_FORM_sdata, Value);
52 void DIEDwarfExpression::EmitUnsigned(unsigned Value) {
53 DU.addUInt(DIE, dwarf::DW_FORM_udata, Value);
55 bool DIEDwarfExpression::isFrameRegister(unsigned MachineReg) {
56 return MachineReg == getTRI()->getFrameRegister(*AP.MF);
60 /// Unit - Unit constructor.
61 DwarfUnit::DwarfUnit(unsigned UID, dwarf::Tag UnitTag, DICompileUnit Node,
62 AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU)
63 : UniqueID(UID), CUNode(Node), UnitDie(UnitTag), DebugInfoOffset(0), Asm(A),
64 DD(DW), DU(DWU), IndexTyDie(nullptr), Section(nullptr) {
65 assert(UnitTag == dwarf::DW_TAG_compile_unit ||
66 UnitTag == dwarf::DW_TAG_type_unit);
67 DIEIntegerOne = new (DIEValueAllocator) DIEInteger(1);
70 DwarfTypeUnit::DwarfTypeUnit(unsigned UID, DwarfCompileUnit &CU, AsmPrinter *A,
71 DwarfDebug *DW, DwarfFile *DWU,
72 MCDwarfDwoLineTable *SplitLineTable)
73 : DwarfUnit(UID, dwarf::DW_TAG_type_unit, CU.getCUNode(), A, DW, DWU),
74 CU(CU), SplitLineTable(SplitLineTable) {
76 addSectionOffset(UnitDie, dwarf::DW_AT_stmt_list, 0);
79 /// ~Unit - Destructor for compile unit.
80 DwarfUnit::~DwarfUnit() {
81 for (unsigned j = 0, M = DIEBlocks.size(); j < M; ++j)
82 DIEBlocks[j]->~DIEBlock();
83 for (unsigned j = 0, M = DIELocs.size(); j < M; ++j)
84 DIELocs[j]->~DIELoc();
87 /// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
88 /// information entry.
89 DIEEntry *DwarfUnit::createDIEEntry(DIE &Entry) {
90 DIEEntry *Value = new (DIEValueAllocator) DIEEntry(Entry);
94 /// getDefaultLowerBound - Return the default lower bound for an array. If the
95 /// DWARF version doesn't handle the language, return -1.
96 int64_t DwarfUnit::getDefaultLowerBound() const {
97 switch (getLanguage()) {
101 case dwarf::DW_LANG_C89:
102 case dwarf::DW_LANG_C99:
103 case dwarf::DW_LANG_C:
104 case dwarf::DW_LANG_C_plus_plus:
105 case dwarf::DW_LANG_ObjC:
106 case dwarf::DW_LANG_ObjC_plus_plus:
109 case dwarf::DW_LANG_Fortran77:
110 case dwarf::DW_LANG_Fortran90:
111 case dwarf::DW_LANG_Fortran95:
114 // The languages below have valid values only if the DWARF version >= 4.
115 case dwarf::DW_LANG_Java:
116 case dwarf::DW_LANG_Python:
117 case dwarf::DW_LANG_UPC:
118 case dwarf::DW_LANG_D:
119 if (dwarf::DWARF_VERSION >= 4)
123 case dwarf::DW_LANG_Ada83:
124 case dwarf::DW_LANG_Ada95:
125 case dwarf::DW_LANG_Cobol74:
126 case dwarf::DW_LANG_Cobol85:
127 case dwarf::DW_LANG_Modula2:
128 case dwarf::DW_LANG_Pascal83:
129 case dwarf::DW_LANG_PLI:
130 if (dwarf::DWARF_VERSION >= 4)
138 /// Check whether the DIE for this MDNode can be shared across CUs.
139 static bool isShareableAcrossCUs(DIDescriptor D) {
140 // When the MDNode can be part of the type system, the DIE can be shared
142 // Combining type units and cross-CU DIE sharing is lower value (since
143 // cross-CU DIE sharing is used in LTO and removes type redundancy at that
144 // level already) but may be implementable for some value in projects
145 // building multiple independent libraries with LTO and then linking those
147 return (D.isType() ||
148 (D.isSubprogram() && !DISubprogram(D).isDefinition())) &&
149 !GenerateDwarfTypeUnits;
152 /// getDIE - Returns the debug information entry map slot for the
153 /// specified debug variable. We delegate the request to DwarfDebug
154 /// when the DIE for this MDNode can be shared across CUs. The mappings
155 /// will be kept in DwarfDebug for shareable DIEs.
156 DIE *DwarfUnit::getDIE(DIDescriptor D) const {
157 if (isShareableAcrossCUs(D))
158 return DU->getDIE(D);
159 return MDNodeToDieMap.lookup(D);
162 /// insertDIE - Insert DIE into the map. We delegate the request to DwarfDebug
163 /// when the DIE for this MDNode can be shared across CUs. The mappings
164 /// will be kept in DwarfDebug for shareable DIEs.
165 void DwarfUnit::insertDIE(DIDescriptor Desc, DIE *D) {
166 if (isShareableAcrossCUs(Desc)) {
167 DU->insertDIE(Desc, D);
170 MDNodeToDieMap.insert(std::make_pair(Desc, D));
173 /// addFlag - Add a flag that is true.
174 void DwarfUnit::addFlag(DIE &Die, dwarf::Attribute Attribute) {
175 if (DD->getDwarfVersion() >= 4)
176 Die.addValue(Attribute, dwarf::DW_FORM_flag_present, DIEIntegerOne);
178 Die.addValue(Attribute, dwarf::DW_FORM_flag, DIEIntegerOne);
181 /// addUInt - Add an unsigned integer attribute data and value.
183 void DwarfUnit::addUInt(DIE &Die, dwarf::Attribute Attribute,
184 Optional<dwarf::Form> Form, uint64_t Integer) {
186 Form = DIEInteger::BestForm(false, Integer);
187 DIEValue *Value = Integer == 1 ? DIEIntegerOne : new (DIEValueAllocator)
189 Die.addValue(Attribute, *Form, Value);
192 void DwarfUnit::addUInt(DIE &Block, dwarf::Form Form, uint64_t Integer) {
193 addUInt(Block, (dwarf::Attribute)0, Form, Integer);
196 /// addSInt - Add an signed integer attribute data and value.
198 void DwarfUnit::addSInt(DIE &Die, dwarf::Attribute Attribute,
199 Optional<dwarf::Form> Form, int64_t Integer) {
201 Form = DIEInteger::BestForm(true, Integer);
202 DIEValue *Value = new (DIEValueAllocator) DIEInteger(Integer);
203 Die.addValue(Attribute, *Form, Value);
206 void DwarfUnit::addSInt(DIELoc &Die, Optional<dwarf::Form> Form,
208 addSInt(Die, (dwarf::Attribute)0, Form, Integer);
211 /// addString - Add a string attribute data and value. We always emit a
212 /// reference to the string pool instead of immediate strings so that DIEs have
213 /// more predictable sizes. In the case of split dwarf we emit an index
214 /// into another table which gets us the static offset into the string
216 void DwarfUnit::addString(DIE &Die, dwarf::Attribute Attribute,
219 return addLocalString(Die, Attribute, String);
221 addIndexedString(Die, Attribute, String);
224 void DwarfUnit::addIndexedString(DIE &Die, dwarf::Attribute Attribute,
226 unsigned idx = DU->getStringPool().getIndex(*Asm, String);
227 DIEValue *Value = new (DIEValueAllocator) DIEInteger(idx);
228 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
229 Die.addValue(Attribute, dwarf::DW_FORM_GNU_str_index, Str);
232 /// addLocalString - Add a string attribute data and value. This is guaranteed
233 /// to be in the local string pool instead of indirected.
234 void DwarfUnit::addLocalString(DIE &Die, dwarf::Attribute Attribute,
236 MCSymbol *Symb = DU->getStringPool().getSymbol(*Asm, String);
238 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
239 Value = new (DIEValueAllocator) DIELabel(Symb);
241 Value = new (DIEValueAllocator) DIEDelta(Symb, DD->getDebugStrSym());
242 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
243 Die.addValue(Attribute, dwarf::DW_FORM_strp, Str);
246 /// addLabel - Add a Dwarf label attribute data and value.
248 void DwarfUnit::addLabel(DIE &Die, dwarf::Attribute Attribute, dwarf::Form Form,
249 const MCSymbol *Label) {
250 DIEValue *Value = new (DIEValueAllocator) DIELabel(Label);
251 Die.addValue(Attribute, Form, Value);
254 void DwarfUnit::addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label) {
255 addLabel(Die, (dwarf::Attribute)0, Form, Label);
258 /// addSectionOffset - Add an offset into a section attribute data and value.
260 void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
262 if (DD->getDwarfVersion() >= 4)
263 addUInt(Die, Attribute, dwarf::DW_FORM_sec_offset, Integer);
265 addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
268 unsigned DwarfTypeUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
269 return SplitLineTable ? SplitLineTable->getFile(DirName, FileName)
270 : getCU().getOrCreateSourceID(FileName, DirName);
273 /// addOpAddress - Add a dwarf op address data and value using the
274 /// form given and an op of either DW_FORM_addr or DW_FORM_GNU_addr_index.
276 void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) {
277 if (!DD->useSplitDwarf()) {
278 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
279 addLabel(Die, dwarf::DW_FORM_udata, Sym);
281 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_addr_index);
282 addUInt(Die, dwarf::DW_FORM_GNU_addr_index,
283 DD->getAddressPool().getIndex(Sym));
287 void DwarfUnit::addLabelDelta(DIE &Die, dwarf::Attribute Attribute,
288 const MCSymbol *Hi, const MCSymbol *Lo) {
289 DIEValue *Value = new (DIEValueAllocator) DIEDelta(Hi, Lo);
290 Die.addValue(Attribute, dwarf::DW_FORM_data4, Value);
293 /// addDIEEntry - Add a DIE attribute data and value.
295 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry) {
296 addDIEEntry(Die, Attribute, createDIEEntry(Entry));
299 void DwarfUnit::addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type) {
300 // Flag the type unit reference as a declaration so that if it contains
301 // members (implicit special members, static data member definitions, member
302 // declarations for definitions in this CU, etc) consumers don't get confused
303 // and think this is a full definition.
304 addFlag(Die, dwarf::DW_AT_declaration);
306 Die.addValue(dwarf::DW_AT_signature, dwarf::DW_FORM_ref_sig8,
307 new (DIEValueAllocator) DIETypeSignature(Type));
310 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
312 const DIE *DieCU = Die.getUnitOrNull();
313 const DIE *EntryCU = Entry->getEntry().getUnitOrNull();
315 // We assume that Die belongs to this CU, if it is not linked to any CU yet.
316 DieCU = &getUnitDie();
318 EntryCU = &getUnitDie();
319 Die.addValue(Attribute,
320 EntryCU == DieCU ? dwarf::DW_FORM_ref4 : dwarf::DW_FORM_ref_addr,
324 /// Create a DIE with the given Tag, add the DIE to its parent, and
325 /// call insertDIE if MD is not null.
326 DIE &DwarfUnit::createAndAddDIE(unsigned Tag, DIE &Parent, DIDescriptor N) {
327 assert(Tag != dwarf::DW_TAG_auto_variable &&
328 Tag != dwarf::DW_TAG_arg_variable);
329 Parent.addChild(make_unique<DIE>((dwarf::Tag)Tag));
330 DIE &Die = *Parent.getChildren().back();
336 /// addBlock - Add block data.
338 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Loc) {
339 Loc->ComputeSize(Asm);
340 DIELocs.push_back(Loc); // Memoize so we can call the destructor later on.
341 Die.addValue(Attribute, Loc->BestForm(DD->getDwarfVersion()), Loc);
344 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute,
346 Block->ComputeSize(Asm);
347 DIEBlocks.push_back(Block); // Memoize so we can call the destructor later on.
348 Die.addValue(Attribute, Block->BestForm(), Block);
351 /// addSourceLine - Add location information to specified debug information
353 void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, StringRef File,
354 StringRef Directory) {
358 unsigned FileID = getOrCreateSourceID(File, Directory);
359 assert(FileID && "Invalid file id");
360 addUInt(Die, dwarf::DW_AT_decl_file, None, FileID);
361 addUInt(Die, dwarf::DW_AT_decl_line, None, Line);
364 /// addSourceLine - Add location information to specified debug information
366 void DwarfUnit::addSourceLine(DIE &Die, DIVariable V) {
367 assert(V.isVariable());
369 addSourceLine(Die, V.getLineNumber(), V.getContext().getFilename(),
370 V.getContext().getDirectory());
373 /// addSourceLine - Add location information to specified debug information
375 void DwarfUnit::addSourceLine(DIE &Die, DIGlobalVariable G) {
376 assert(G.isGlobalVariable());
378 addSourceLine(Die, G.getLineNumber(), G.getFilename(), G.getDirectory());
381 /// addSourceLine - Add location information to specified debug information
383 void DwarfUnit::addSourceLine(DIE &Die, DISubprogram SP) {
384 assert(SP.isSubprogram());
386 addSourceLine(Die, SP.getLineNumber(), SP.getFilename(), SP.getDirectory());
389 /// addSourceLine - Add location information to specified debug information
391 void DwarfUnit::addSourceLine(DIE &Die, DIType Ty) {
394 addSourceLine(Die, Ty.getLineNumber(), Ty.getFilename(), Ty.getDirectory());
397 /// addSourceLine - Add location information to specified debug information
399 void DwarfUnit::addSourceLine(DIE &Die, DIObjCProperty Ty) {
400 assert(Ty.isObjCProperty());
402 DIFile File = Ty.getFile();
403 addSourceLine(Die, Ty.getLineNumber(), File.getFilename(),
404 File.getDirectory());
407 /// addSourceLine - Add location information to specified debug information
409 void DwarfUnit::addSourceLine(DIE &Die, DINameSpace NS) {
412 addSourceLine(Die, NS.getLineNumber(), NS.getFilename(), NS.getDirectory());
415 /// addRegisterOp - Add register operand.
416 bool DwarfUnit::addRegisterOpPiece(DIELoc &TheDie, unsigned Reg,
417 unsigned SizeInBits, unsigned OffsetInBits) {
418 DIEDwarfExpression Expr(*Asm, *this, TheDie);
419 Expr.AddMachineRegPiece(Reg, SizeInBits, OffsetInBits);
423 /// addRegisterOffset - Add register offset.
424 bool DwarfUnit::addRegisterOffset(DIELoc &TheDie, unsigned Reg,
426 DIEDwarfExpression Expr(*Asm, *this, TheDie);
427 return Expr.AddMachineRegIndirect(Reg, Offset);
430 /* Byref variables, in Blocks, are declared by the programmer as "SomeType
431 VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
432 gives the variable VarName either the struct, or a pointer to the struct, as
433 its type. This is necessary for various behind-the-scenes things the
434 compiler needs to do with by-reference variables in Blocks.
436 However, as far as the original *programmer* is concerned, the variable
437 should still have type 'SomeType', as originally declared.
439 The function getBlockByrefType dives into the __Block_byref_x_VarName
440 struct to find the original type of the variable, which is then assigned to
441 the variable's Debug Information Entry as its real type. So far, so good.
442 However now the debugger will expect the variable VarName to have the type
443 SomeType. So we need the location attribute for the variable to be an
444 expression that explains to the debugger how to navigate through the
445 pointers and struct to find the actual variable of type SomeType.
447 The following function does just that. We start by getting
448 the "normal" location for the variable. This will be the location
449 of either the struct __Block_byref_x_VarName or the pointer to the
450 struct __Block_byref_x_VarName.
452 The struct will look something like:
454 struct __Block_byref_x_VarName {
456 struct __Block_byref_x_VarName *forwarding;
457 ... <various other fields>
459 ... <maybe more fields>
462 If we are given the struct directly (as our starting point) we
463 need to tell the debugger to:
465 1). Add the offset of the forwarding field.
467 2). Follow that pointer to get the real __Block_byref_x_VarName
468 struct to use (the real one may have been copied onto the heap).
470 3). Add the offset for the field VarName, to find the actual variable.
472 If we started with a pointer to the struct, then we need to
473 dereference that pointer first, before the other steps.
474 Translating this into DWARF ops, we will need to append the following
475 to the current location description for the variable:
477 DW_OP_deref -- optional, if we start with a pointer
478 DW_OP_plus_uconst <forward_fld_offset>
480 DW_OP_plus_uconst <varName_fld_offset>
482 That is what this function does. */
484 /// addBlockByrefAddress - Start with the address based on the location
485 /// provided, and generate the DWARF information necessary to find the
486 /// actual Block variable (navigating the Block struct) based on the
487 /// starting location. Add the DWARF information to the die. For
488 /// more information, read large comment just above here.
490 void DwarfUnit::addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
491 dwarf::Attribute Attribute,
492 const MachineLocation &Location) {
493 DIType Ty = DV.getType();
495 uint16_t Tag = Ty.getTag();
496 bool isPointer = false;
498 StringRef varName = DV.getName();
500 if (Tag == dwarf::DW_TAG_pointer_type) {
501 DIDerivedType DTy(Ty);
502 TmpTy = resolve(DTy.getTypeDerivedFrom());
506 DICompositeType blockStruct(TmpTy);
508 // Find the __forwarding field and the variable field in the __Block_byref
510 DIArray Fields = blockStruct.getElements();
511 DIDerivedType varField;
512 DIDerivedType forwardingField;
514 for (unsigned i = 0, N = Fields.getNumElements(); i < N; ++i) {
515 DIDerivedType DT(Fields.getElement(i));
516 StringRef fieldName = DT.getName();
517 if (fieldName == "__forwarding")
518 forwardingField = DT;
519 else if (fieldName == varName)
523 // Get the offsets for the forwarding field and the variable field.
524 unsigned forwardingFieldOffset = forwardingField.getOffsetInBits() >> 3;
525 unsigned varFieldOffset = varField.getOffsetInBits() >> 2;
527 // Decode the original location, and use that as the start of the byref
528 // variable's location.
529 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
532 if (Location.isReg())
533 validReg = addRegisterOpPiece(*Loc, Location.getReg());
535 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
540 // If we started with a pointer to the __Block_byref... struct, then
541 // the first thing we need to do is dereference the pointer (DW_OP_deref).
543 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
545 // Next add the offset for the '__forwarding' field:
546 // DW_OP_plus_uconst ForwardingFieldOffset. Note there's no point in
547 // adding the offset if it's 0.
548 if (forwardingFieldOffset > 0) {
549 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
550 addUInt(*Loc, dwarf::DW_FORM_udata, forwardingFieldOffset);
553 // Now dereference the __forwarding field to get to the real __Block_byref
554 // struct: DW_OP_deref.
555 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
557 // Now that we've got the real __Block_byref... struct, add the offset
558 // for the variable's field to get to the location of the actual variable:
559 // DW_OP_plus_uconst varFieldOffset. Again, don't add if it's 0.
560 if (varFieldOffset > 0) {
561 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
562 addUInt(*Loc, dwarf::DW_FORM_udata, varFieldOffset);
565 // Now attach the location information to the DIE.
566 addBlock(Die, Attribute, Loc);
569 /// Return true if type encoding is unsigned.
570 static bool isUnsignedDIType(DwarfDebug *DD, DIType Ty) {
571 DIDerivedType DTy(Ty);
572 if (DTy.isDerivedType()) {
573 dwarf::Tag T = (dwarf::Tag)Ty.getTag();
574 // Encode pointer constants as unsigned bytes. This is used at least for
575 // null pointer constant emission.
576 // (Pieces of) aggregate types that get hacked apart by SROA may also be
577 // represented by a constant. Encode them as unsigned bytes.
578 // FIXME: reference and rvalue_reference /probably/ shouldn't be allowed
579 // here, but accept them for now due to a bug in SROA producing bogus
581 if (T == dwarf::DW_TAG_array_type ||
582 T == dwarf::DW_TAG_class_type ||
583 T == dwarf::DW_TAG_pointer_type ||
584 T == dwarf::DW_TAG_ptr_to_member_type ||
585 T == dwarf::DW_TAG_reference_type ||
586 T == dwarf::DW_TAG_rvalue_reference_type ||
587 T == dwarf::DW_TAG_structure_type)
589 assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
590 T == dwarf::DW_TAG_volatile_type ||
591 T == dwarf::DW_TAG_restrict_type ||
592 T == dwarf::DW_TAG_enumeration_type);
593 if (DITypeRef Deriv = DTy.getTypeDerivedFrom())
594 return isUnsignedDIType(DD, DD->resolve(Deriv));
595 // FIXME: Enums without a fixed underlying type have unknown signedness
596 // here, leading to incorrectly emitted constants.
597 assert(DTy.getTag() == dwarf::DW_TAG_enumeration_type);
602 assert(BTy.isBasicType());
603 unsigned Encoding = BTy.getEncoding();
604 assert((Encoding == dwarf::DW_ATE_unsigned ||
605 Encoding == dwarf::DW_ATE_unsigned_char ||
606 Encoding == dwarf::DW_ATE_signed ||
607 Encoding == dwarf::DW_ATE_signed_char ||
608 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean ||
609 (Ty.getTag() == dwarf::DW_TAG_unspecified_type &&
610 Ty.getName() == "decltype(nullptr)")) &&
611 "Unsupported encoding");
612 return (Encoding == dwarf::DW_ATE_unsigned ||
613 Encoding == dwarf::DW_ATE_unsigned_char ||
614 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean ||
615 Ty.getTag() == dwarf::DW_TAG_unspecified_type);
618 /// If this type is derived from a base type then return base type size.
619 static uint64_t getBaseTypeSize(DwarfDebug *DD, DIDerivedType Ty) {
620 unsigned Tag = Ty.getTag();
622 if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
623 Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
624 Tag != dwarf::DW_TAG_restrict_type)
625 return Ty.getSizeInBits();
627 DIType BaseType = DD->resolve(Ty.getTypeDerivedFrom());
629 // If this type is not derived from any type or the type is a declaration then
630 // take conservative approach.
631 if (!BaseType.isValid() || BaseType.isForwardDecl())
632 return Ty.getSizeInBits();
634 // If this is a derived type, go ahead and get the base type, unless it's a
635 // reference then it's just the size of the field. Pointer types have no need
636 // of this since they're a different type of qualification on the type.
637 if (BaseType.getTag() == dwarf::DW_TAG_reference_type ||
638 BaseType.getTag() == dwarf::DW_TAG_rvalue_reference_type)
639 return Ty.getSizeInBits();
641 if (BaseType.isDerivedType())
642 return getBaseTypeSize(DD, DIDerivedType(BaseType));
644 return BaseType.getSizeInBits();
647 /// addConstantFPValue - Add constant value entry in variable DIE.
648 void DwarfUnit::addConstantFPValue(DIE &Die, const MachineOperand &MO) {
649 assert(MO.isFPImm() && "Invalid machine operand!");
650 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
651 APFloat FPImm = MO.getFPImm()->getValueAPF();
653 // Get the raw data form of the floating point.
654 const APInt FltVal = FPImm.bitcastToAPInt();
655 const char *FltPtr = (const char *)FltVal.getRawData();
657 int NumBytes = FltVal.getBitWidth() / 8; // 8 bits per byte.
658 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
659 int Incr = (LittleEndian ? 1 : -1);
660 int Start = (LittleEndian ? 0 : NumBytes - 1);
661 int Stop = (LittleEndian ? NumBytes : -1);
663 // Output the constant to DWARF one byte at a time.
664 for (; Start != Stop; Start += Incr)
665 addUInt(*Block, dwarf::DW_FORM_data1, (unsigned char)0xFF & FltPtr[Start]);
667 addBlock(Die, dwarf::DW_AT_const_value, Block);
670 /// addConstantFPValue - Add constant value entry in variable DIE.
671 void DwarfUnit::addConstantFPValue(DIE &Die, const ConstantFP *CFP) {
672 // Pass this down to addConstantValue as an unsigned bag of bits.
673 addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
676 /// addConstantValue - Add constant value entry in variable DIE.
677 void DwarfUnit::addConstantValue(DIE &Die, const ConstantInt *CI, DIType Ty) {
678 addConstantValue(Die, CI->getValue(), Ty);
681 /// addConstantValue - Add constant value entry in variable DIE.
682 void DwarfUnit::addConstantValue(DIE &Die, const MachineOperand &MO,
684 assert(MO.isImm() && "Invalid machine operand!");
686 addConstantValue(Die, isUnsignedDIType(DD, Ty), MO.getImm());
689 void DwarfUnit::addConstantValue(DIE &Die, bool Unsigned, uint64_t Val) {
690 // FIXME: This is a bit conservative/simple - it emits negative values always
691 // sign extended to 64 bits rather than minimizing the number of bytes.
692 addUInt(Die, dwarf::DW_AT_const_value,
693 Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata, Val);
696 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, DIType Ty) {
697 addConstantValue(Die, Val, isUnsignedDIType(DD, Ty));
700 // addConstantValue - Add constant value entry in variable DIE.
701 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
702 unsigned CIBitWidth = Val.getBitWidth();
703 if (CIBitWidth <= 64) {
704 addConstantValue(Die, Unsigned,
705 Unsigned ? Val.getZExtValue() : Val.getSExtValue());
709 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
711 // Get the raw data form of the large APInt.
712 const uint64_t *Ptr64 = Val.getRawData();
714 int NumBytes = Val.getBitWidth() / 8; // 8 bits per byte.
715 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
717 // Output the constant to DWARF one byte at a time.
718 for (int i = 0; i < NumBytes; i++) {
721 c = Ptr64[i / 8] >> (8 * (i & 7));
723 c = Ptr64[(NumBytes - 1 - i) / 8] >> (8 * ((NumBytes - 1 - i) & 7));
724 addUInt(*Block, dwarf::DW_FORM_data1, c);
727 addBlock(Die, dwarf::DW_AT_const_value, Block);
730 /// addTemplateParams - Add template parameters into buffer.
731 void DwarfUnit::addTemplateParams(DIE &Buffer, DIArray TParams) {
732 // Add template parameters.
733 for (unsigned i = 0, e = TParams.getNumElements(); i != e; ++i) {
734 DIDescriptor Element = TParams.getElement(i);
735 if (Element.isTemplateTypeParameter())
736 constructTemplateTypeParameterDIE(Buffer,
737 DITemplateTypeParameter(Element));
738 else if (Element.isTemplateValueParameter())
739 constructTemplateValueParameterDIE(Buffer,
740 DITemplateValueParameter(Element));
744 /// getOrCreateContextDIE - Get context owner's DIE.
745 DIE *DwarfUnit::getOrCreateContextDIE(DIScope Context) {
746 if (!Context || Context.isFile())
747 return &getUnitDie();
748 if (Context.isType())
749 return getOrCreateTypeDIE(DIType(Context));
750 if (Context.isNameSpace())
751 return getOrCreateNameSpace(DINameSpace(Context));
752 if (Context.isSubprogram())
753 return getOrCreateSubprogramDIE(DISubprogram(Context));
754 return getDIE(Context);
757 DIE *DwarfUnit::createTypeDIE(DICompositeType Ty) {
758 DIScope Context = resolve(Ty.getContext());
759 DIE *ContextDIE = getOrCreateContextDIE(Context);
761 if (DIE *TyDIE = getDIE(Ty))
765 DIE &TyDIE = createAndAddDIE(Ty.getTag(), *ContextDIE, Ty);
767 constructTypeDIE(TyDIE, Ty);
769 updateAcceleratorTables(Context, Ty, TyDIE);
773 /// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
775 DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
781 assert(Ty == resolve(Ty.getRef()) &&
782 "type was not uniqued, possible ODR violation.");
784 // DW_TAG_restrict_type is not supported in DWARF2
785 if (Ty.getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
786 return getOrCreateTypeDIE(resolve(DIDerivedType(Ty).getTypeDerivedFrom()));
788 // Construct the context before querying for the existence of the DIE in case
789 // such construction creates the DIE.
790 DIScope Context = resolve(Ty.getContext());
791 DIE *ContextDIE = getOrCreateContextDIE(Context);
794 if (DIE *TyDIE = getDIE(Ty))
798 DIE &TyDIE = createAndAddDIE(Ty.getTag(), *ContextDIE, Ty);
800 updateAcceleratorTables(Context, Ty, TyDIE);
802 if (Ty.isBasicType())
803 constructTypeDIE(TyDIE, DIBasicType(Ty));
804 else if (Ty.isCompositeType()) {
805 DICompositeType CTy(Ty);
806 if (GenerateDwarfTypeUnits && !Ty.isForwardDecl())
807 if (MDString *TypeId = CTy.getIdentifier()) {
808 DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);
809 // Skip updating the accelerator tables since this is not the full type.
812 constructTypeDIE(TyDIE, CTy);
814 assert(Ty.isDerivedType() && "Unknown kind of DIType");
815 constructTypeDIE(TyDIE, DIDerivedType(Ty));
821 void DwarfUnit::updateAcceleratorTables(DIScope Context, DIType Ty,
823 if (!Ty.getName().empty() && !Ty.isForwardDecl()) {
824 bool IsImplementation = 0;
825 if (Ty.isCompositeType()) {
826 DICompositeType CT(Ty);
827 // A runtime language of 0 actually means C/C++ and that any
828 // non-negative value is some version of Objective-C/C++.
829 IsImplementation = (CT.getRunTimeLang() == 0) || CT.isObjcClassComplete();
831 unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
832 DD->addAccelType(Ty.getName(), TyDIE, Flags);
834 if (!Context || Context.isCompileUnit() || Context.isFile() ||
835 Context.isNameSpace())
836 addGlobalType(Ty, TyDIE, Context);
840 /// addType - Add a new type attribute to the specified entity.
841 void DwarfUnit::addType(DIE &Entity, DIType Ty, dwarf::Attribute Attribute) {
842 assert(Ty && "Trying to add a type that doesn't exist?");
844 // Check for pre-existence.
845 DIEEntry *Entry = getDIEEntry(Ty);
846 // If it exists then use the existing value.
848 addDIEEntry(Entity, Attribute, Entry);
853 DIE *Buffer = getOrCreateTypeDIE(Ty);
856 Entry = createDIEEntry(*Buffer);
857 insertDIEEntry(Ty, Entry);
858 addDIEEntry(Entity, Attribute, Entry);
861 /// getParentContextString - Walks the metadata parent chain in a language
862 /// specific manner (using the compile unit language) and returns
863 /// it as a string. This is done at the metadata level because DIEs may
864 /// not currently have been added to the parent context and walking the
865 /// DIEs looking for names is more expensive than walking the metadata.
866 std::string DwarfUnit::getParentContextString(DIScope Context) const {
870 // FIXME: Decide whether to implement this for non-C++ languages.
871 if (getLanguage() != dwarf::DW_LANG_C_plus_plus)
875 SmallVector<DIScope, 1> Parents;
876 while (!Context.isCompileUnit()) {
877 Parents.push_back(Context);
878 if (Context.getContext())
879 Context = resolve(Context.getContext());
881 // Structure, etc types will have a NULL context if they're at the top
886 // Reverse iterate over our list to go from the outermost construct to the
888 for (SmallVectorImpl<DIScope>::reverse_iterator I = Parents.rbegin(),
892 StringRef Name = Ctx.getName();
893 if (Name.empty() && Ctx.isNameSpace())
894 Name = "(anonymous namespace)";
903 /// constructTypeDIE - Construct basic type die from DIBasicType.
904 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIBasicType BTy) {
905 // Get core information.
906 StringRef Name = BTy.getName();
907 // Add name if not anonymous or intermediate type.
909 addString(Buffer, dwarf::DW_AT_name, Name);
911 // An unspecified type only has a name attribute.
912 if (BTy.getTag() == dwarf::DW_TAG_unspecified_type)
915 addUInt(Buffer, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
918 uint64_t Size = BTy.getSizeInBits() >> 3;
919 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
922 /// constructTypeDIE - Construct derived type die from DIDerivedType.
923 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIDerivedType DTy) {
924 // Get core information.
925 StringRef Name = DTy.getName();
926 uint64_t Size = DTy.getSizeInBits() >> 3;
927 uint16_t Tag = Buffer.getTag();
929 // Map to main type, void will not have a type.
930 DIType FromTy = resolve(DTy.getTypeDerivedFrom());
932 addType(Buffer, FromTy);
934 // Add name if not anonymous or intermediate type.
936 addString(Buffer, dwarf::DW_AT_name, Name);
938 // Add size if non-zero (derived types might be zero-sized.)
939 if (Size && Tag != dwarf::DW_TAG_pointer_type
940 && Tag != dwarf::DW_TAG_ptr_to_member_type)
941 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
943 if (Tag == dwarf::DW_TAG_ptr_to_member_type)
944 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
945 *getOrCreateTypeDIE(resolve(DTy.getClassType())));
946 // Add source line info if available and TyDesc is not a forward declaration.
947 if (!DTy.isForwardDecl())
948 addSourceLine(Buffer, DTy);
951 /// constructSubprogramArguments - Construct function argument DIEs.
952 void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DITypeArray Args) {
953 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) {
954 DIType Ty = resolve(Args.getElement(i));
956 assert(i == N-1 && "Unspecified parameter must be the last argument");
957 createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
959 DIE &Arg = createAndAddDIE(dwarf::DW_TAG_formal_parameter, Buffer);
961 if (Ty.isArtificial())
962 addFlag(Arg, dwarf::DW_AT_artificial);
967 /// constructTypeDIE - Construct type DIE from DICompositeType.
968 void DwarfUnit::constructTypeDIE(DIE &Buffer, DICompositeType CTy) {
969 // Add name if not anonymous or intermediate type.
970 StringRef Name = CTy.getName();
972 uint64_t Size = CTy.getSizeInBits() >> 3;
973 uint16_t Tag = Buffer.getTag();
976 case dwarf::DW_TAG_array_type:
977 constructArrayTypeDIE(Buffer, CTy);
979 case dwarf::DW_TAG_enumeration_type:
980 constructEnumTypeDIE(Buffer, CTy);
982 case dwarf::DW_TAG_subroutine_type: {
983 // Add return type. A void return won't have a type.
984 DITypeArray Elements = DISubroutineType(CTy).getTypeArray();
985 DIType RTy(resolve(Elements.getElement(0)));
987 addType(Buffer, RTy);
989 bool isPrototyped = true;
990 if (Elements.getNumElements() == 2 &&
991 !Elements.getElement(1))
992 isPrototyped = false;
994 constructSubprogramArguments(Buffer, Elements);
996 // Add prototype flag if we're dealing with a C language and the
997 // function has been prototyped.
998 uint16_t Language = getLanguage();
1000 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1001 Language == dwarf::DW_LANG_ObjC))
1002 addFlag(Buffer, dwarf::DW_AT_prototyped);
1004 if (CTy.isLValueReference())
1005 addFlag(Buffer, dwarf::DW_AT_reference);
1007 if (CTy.isRValueReference())
1008 addFlag(Buffer, dwarf::DW_AT_rvalue_reference);
1010 case dwarf::DW_TAG_structure_type:
1011 case dwarf::DW_TAG_union_type:
1012 case dwarf::DW_TAG_class_type: {
1013 // Add elements to structure type.
1014 DIArray Elements = CTy.getElements();
1015 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1016 DIDescriptor Element = Elements.getElement(i);
1017 if (Element.isSubprogram())
1018 getOrCreateSubprogramDIE(DISubprogram(Element));
1019 else if (Element.isDerivedType()) {
1020 DIDerivedType DDTy(Element);
1021 if (DDTy.getTag() == dwarf::DW_TAG_friend) {
1022 DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
1023 addType(ElemDie, resolve(DDTy.getTypeDerivedFrom()),
1024 dwarf::DW_AT_friend);
1025 } else if (DDTy.isStaticMember()) {
1026 getOrCreateStaticMemberDIE(DDTy);
1028 constructMemberDIE(Buffer, DDTy);
1030 } else if (Element.isObjCProperty()) {
1031 DIObjCProperty Property(Element);
1032 DIE &ElemDie = createAndAddDIE(Property.getTag(), Buffer);
1033 StringRef PropertyName = Property.getObjCPropertyName();
1034 addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
1035 if (Property.getType())
1036 addType(ElemDie, Property.getType());
1037 addSourceLine(ElemDie, Property);
1038 StringRef GetterName = Property.getObjCPropertyGetterName();
1039 if (!GetterName.empty())
1040 addString(ElemDie, dwarf::DW_AT_APPLE_property_getter, GetterName);
1041 StringRef SetterName = Property.getObjCPropertySetterName();
1042 if (!SetterName.empty())
1043 addString(ElemDie, dwarf::DW_AT_APPLE_property_setter, SetterName);
1044 unsigned PropertyAttributes = 0;
1045 if (Property.isReadOnlyObjCProperty())
1046 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_readonly;
1047 if (Property.isReadWriteObjCProperty())
1048 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_readwrite;
1049 if (Property.isAssignObjCProperty())
1050 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_assign;
1051 if (Property.isRetainObjCProperty())
1052 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_retain;
1053 if (Property.isCopyObjCProperty())
1054 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_copy;
1055 if (Property.isNonAtomicObjCProperty())
1056 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_nonatomic;
1057 if (PropertyAttributes)
1058 addUInt(ElemDie, dwarf::DW_AT_APPLE_property_attribute, None,
1059 PropertyAttributes);
1061 DIEEntry *Entry = getDIEEntry(Element);
1063 Entry = createDIEEntry(ElemDie);
1064 insertDIEEntry(Element, Entry);
1070 if (CTy.isAppleBlockExtension())
1071 addFlag(Buffer, dwarf::DW_AT_APPLE_block);
1073 // This is outside the DWARF spec, but GDB expects a DW_AT_containing_type
1074 // inside C++ composite types to point to the base class with the vtable.
1075 DICompositeType ContainingType(resolve(CTy.getContainingType()));
1077 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
1078 *getOrCreateTypeDIE(ContainingType));
1080 if (CTy.isObjcClassComplete())
1081 addFlag(Buffer, dwarf::DW_AT_APPLE_objc_complete_type);
1083 // Add template parameters to a class, structure or union types.
1084 // FIXME: The support isn't in the metadata for this yet.
1085 if (Tag == dwarf::DW_TAG_class_type ||
1086 Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
1087 addTemplateParams(Buffer, CTy.getTemplateParams());
1095 // Add name if not anonymous or intermediate type.
1097 addString(Buffer, dwarf::DW_AT_name, Name);
1099 if (Tag == dwarf::DW_TAG_enumeration_type ||
1100 Tag == dwarf::DW_TAG_class_type || Tag == dwarf::DW_TAG_structure_type ||
1101 Tag == dwarf::DW_TAG_union_type) {
1102 // Add size if non-zero (derived types might be zero-sized.)
1103 // TODO: Do we care about size for enum forward declarations?
1105 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
1106 else if (!CTy.isForwardDecl())
1107 // Add zero size if it is not a forward declaration.
1108 addUInt(Buffer, dwarf::DW_AT_byte_size, None, 0);
1110 // If we're a forward decl, say so.
1111 if (CTy.isForwardDecl())
1112 addFlag(Buffer, dwarf::DW_AT_declaration);
1114 // Add source line info if available.
1115 if (!CTy.isForwardDecl())
1116 addSourceLine(Buffer, CTy);
1118 // No harm in adding the runtime language to the declaration.
1119 unsigned RLang = CTy.getRunTimeLang();
1121 addUInt(Buffer, dwarf::DW_AT_APPLE_runtime_class, dwarf::DW_FORM_data1,
1126 /// constructTemplateTypeParameterDIE - Construct new DIE for the given
1127 /// DITemplateTypeParameter.
1128 void DwarfUnit::constructTemplateTypeParameterDIE(DIE &Buffer,
1129 DITemplateTypeParameter TP) {
1131 createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
1132 // Add the type if it exists, it could be void and therefore no type.
1134 addType(ParamDIE, resolve(TP.getType()));
1135 if (!TP.getName().empty())
1136 addString(ParamDIE, dwarf::DW_AT_name, TP.getName());
1139 /// constructTemplateValueParameterDIE - Construct new DIE for the given
1140 /// DITemplateValueParameter.
1142 DwarfUnit::constructTemplateValueParameterDIE(DIE &Buffer,
1143 DITemplateValueParameter VP) {
1144 DIE &ParamDIE = createAndAddDIE(VP.getTag(), Buffer);
1146 // Add the type if there is one, template template and template parameter
1147 // packs will not have a type.
1148 if (VP.getTag() == dwarf::DW_TAG_template_value_parameter)
1149 addType(ParamDIE, resolve(VP.getType()));
1150 if (!VP.getName().empty())
1151 addString(ParamDIE, dwarf::DW_AT_name, VP.getName());
1152 if (Metadata *Val = VP.getValue()) {
1153 if (ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(Val))
1154 addConstantValue(ParamDIE, CI, resolve(VP.getType()));
1155 else if (GlobalValue *GV = mdconst::dyn_extract<GlobalValue>(Val)) {
1156 // For declaration non-type template parameters (such as global values and
1158 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
1159 addOpAddress(*Loc, Asm->getSymbol(GV));
1160 // Emit DW_OP_stack_value to use the address as the immediate value of the
1161 // parameter, rather than a pointer to it.
1162 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_stack_value);
1163 addBlock(ParamDIE, dwarf::DW_AT_location, Loc);
1164 } else if (VP.getTag() == dwarf::DW_TAG_GNU_template_template_param) {
1165 assert(isa<MDString>(Val));
1166 addString(ParamDIE, dwarf::DW_AT_GNU_template_name,
1167 cast<MDString>(Val)->getString());
1168 } else if (VP.getTag() == dwarf::DW_TAG_GNU_template_parameter_pack) {
1169 assert(isa<MDNode>(Val));
1170 DIArray A(cast<MDNode>(Val));
1171 addTemplateParams(ParamDIE, A);
1176 /// getOrCreateNameSpace - Create a DIE for DINameSpace.
1177 DIE *DwarfUnit::getOrCreateNameSpace(DINameSpace NS) {
1178 // Construct the context before querying for the existence of the DIE in case
1179 // such construction creates the DIE.
1180 DIE *ContextDIE = getOrCreateContextDIE(NS.getContext());
1182 if (DIE *NDie = getDIE(NS))
1184 DIE &NDie = createAndAddDIE(dwarf::DW_TAG_namespace, *ContextDIE, NS);
1186 StringRef Name = NS.getName();
1188 addString(NDie, dwarf::DW_AT_name, NS.getName());
1190 Name = "(anonymous namespace)";
1191 DD->addAccelNamespace(Name, NDie);
1192 addGlobalName(Name, NDie, NS.getContext());
1193 addSourceLine(NDie, NS);
1197 /// getOrCreateSubprogramDIE - Create new DIE using SP.
1198 DIE *DwarfUnit::getOrCreateSubprogramDIE(DISubprogram SP, bool Minimal) {
1199 // Construct the context before querying for the existence of the DIE in case
1200 // such construction creates the DIE (as is the case for member function
1203 Minimal ? &getUnitDie() : getOrCreateContextDIE(resolve(SP.getContext()));
1205 if (DIE *SPDie = getDIE(SP))
1208 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
1210 // Add subprogram definitions to the CU die directly.
1211 ContextDIE = &getUnitDie();
1212 // Build the decl now to ensure it precedes the definition.
1213 getOrCreateSubprogramDIE(SPDecl);
1217 // DW_TAG_inlined_subroutine may refer to this DIE.
1218 DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
1220 // Stop here and fill this in later, depending on whether or not this
1221 // subprogram turns out to have inlined instances or not.
1222 if (SP.isDefinition())
1225 applySubprogramAttributes(SP, SPDie);
1229 bool DwarfUnit::applySubprogramDefinitionAttributes(DISubprogram SP,
1231 DIE *DeclDie = nullptr;
1232 StringRef DeclLinkageName;
1233 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
1234 DeclDie = getDIE(SPDecl);
1235 assert(DeclDie && "This DIE should've already been constructed when the "
1236 "definition DIE was created in "
1237 "getOrCreateSubprogramDIE");
1238 DeclLinkageName = SPDecl.getLinkageName();
1241 // Add function template parameters.
1242 addTemplateParams(SPDie, SP.getTemplateParams());
1244 // Add the linkage name if we have one and it isn't in the Decl.
1245 StringRef LinkageName = SP.getLinkageName();
1246 assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
1247 LinkageName == DeclLinkageName) &&
1248 "decl has a linkage name and it is different");
1249 if (!LinkageName.empty() && DeclLinkageName.empty())
1250 addString(SPDie, dwarf::DW_AT_MIPS_linkage_name,
1251 GlobalValue::getRealLinkageName(LinkageName));
1256 // Refer to the function declaration where all the other attributes will be
1258 addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
1262 void DwarfUnit::applySubprogramAttributes(DISubprogram SP, DIE &SPDie,
1265 if (applySubprogramDefinitionAttributes(SP, SPDie))
1268 // Constructors and operators for anonymous aggregates do not have names.
1269 if (!SP.getName().empty())
1270 addString(SPDie, dwarf::DW_AT_name, SP.getName());
1272 // Skip the rest of the attributes under -gmlt to save space.
1276 addSourceLine(SPDie, SP);
1278 // Add the prototype if we have a prototype and we have a C like
1280 uint16_t Language = getLanguage();
1281 if (SP.isPrototyped() &&
1282 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1283 Language == dwarf::DW_LANG_ObjC))
1284 addFlag(SPDie, dwarf::DW_AT_prototyped);
1286 DISubroutineType SPTy = SP.getType();
1287 assert(SPTy.getTag() == dwarf::DW_TAG_subroutine_type &&
1288 "the type of a subprogram should be a subroutine");
1290 DITypeArray Args = SPTy.getTypeArray();
1291 // Add a return type. If this is a type like a C/C++ void type we don't add a
1293 if (resolve(Args.getElement(0)))
1294 addType(SPDie, DIType(resolve(Args.getElement(0))));
1296 unsigned VK = SP.getVirtuality();
1298 addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1, VK);
1299 DIELoc *Block = getDIELoc();
1300 addUInt(*Block, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1301 addUInt(*Block, dwarf::DW_FORM_udata, SP.getVirtualIndex());
1302 addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
1303 ContainingTypeMap.insert(
1304 std::make_pair(&SPDie, resolve(SP.getContainingType())));
1307 if (!SP.isDefinition()) {
1308 addFlag(SPDie, dwarf::DW_AT_declaration);
1310 // Add arguments. Do not add arguments for subprogram definition. They will
1311 // be handled while processing variables.
1312 constructSubprogramArguments(SPDie, Args);
1315 if (SP.isArtificial())
1316 addFlag(SPDie, dwarf::DW_AT_artificial);
1318 if (!SP.isLocalToUnit())
1319 addFlag(SPDie, dwarf::DW_AT_external);
1321 if (SP.isOptimized())
1322 addFlag(SPDie, dwarf::DW_AT_APPLE_optimized);
1324 if (unsigned isa = Asm->getISAEncoding()) {
1325 addUInt(SPDie, dwarf::DW_AT_APPLE_isa, dwarf::DW_FORM_flag, isa);
1328 if (SP.isLValueReference())
1329 addFlag(SPDie, dwarf::DW_AT_reference);
1331 if (SP.isRValueReference())
1332 addFlag(SPDie, dwarf::DW_AT_rvalue_reference);
1334 if (SP.isProtected())
1335 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1336 dwarf::DW_ACCESS_protected);
1337 else if (SP.isPrivate())
1338 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1339 dwarf::DW_ACCESS_private);
1340 else if (SP.isPublic())
1341 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1342 dwarf::DW_ACCESS_public);
1344 if (SP.isExplicit())
1345 addFlag(SPDie, dwarf::DW_AT_explicit);
1348 /// constructSubrangeDIE - Construct subrange DIE from DISubrange.
1349 void DwarfUnit::constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy) {
1350 DIE &DW_Subrange = createAndAddDIE(dwarf::DW_TAG_subrange_type, Buffer);
1351 addDIEEntry(DW_Subrange, dwarf::DW_AT_type, *IndexTy);
1353 // The LowerBound value defines the lower bounds which is typically zero for
1354 // C/C++. The Count value is the number of elements. Values are 64 bit. If
1355 // Count == -1 then the array is unbounded and we do not emit
1356 // DW_AT_lower_bound and DW_AT_count attributes.
1357 int64_t LowerBound = SR.getLo();
1358 int64_t DefaultLowerBound = getDefaultLowerBound();
1359 int64_t Count = SR.getCount();
1361 if (DefaultLowerBound == -1 || LowerBound != DefaultLowerBound)
1362 addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, None, LowerBound);
1365 // FIXME: An unbounded array should reference the expression that defines
1367 addUInt(DW_Subrange, dwarf::DW_AT_count, None, Count);
1370 DIE *DwarfUnit::getIndexTyDie() {
1373 // Construct an integer type to use for indexes.
1374 IndexTyDie = &createAndAddDIE(dwarf::DW_TAG_base_type, UnitDie);
1375 addString(*IndexTyDie, dwarf::DW_AT_name, "sizetype");
1376 addUInt(*IndexTyDie, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
1377 addUInt(*IndexTyDie, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
1378 dwarf::DW_ATE_unsigned);
1382 /// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
1383 void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, DICompositeType CTy) {
1385 addFlag(Buffer, dwarf::DW_AT_GNU_vector);
1387 // Emit the element type.
1388 addType(Buffer, resolve(CTy.getTypeDerivedFrom()));
1390 // Get an anonymous type for index type.
1391 // FIXME: This type should be passed down from the front end
1392 // as different languages may have different sizes for indexes.
1393 DIE *IdxTy = getIndexTyDie();
1395 // Add subranges to array type.
1396 DIArray Elements = CTy.getElements();
1397 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1398 DIDescriptor Element = Elements.getElement(i);
1399 if (Element.getTag() == dwarf::DW_TAG_subrange_type)
1400 constructSubrangeDIE(Buffer, DISubrange(Element), IdxTy);
1404 /// constructEnumTypeDIE - Construct an enum type DIE from DICompositeType.
1405 void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, DICompositeType CTy) {
1406 DIArray Elements = CTy.getElements();
1408 // Add enumerators to enumeration type.
1409 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1410 DIEnumerator Enum(Elements.getElement(i));
1411 if (Enum.isEnumerator()) {
1412 DIE &Enumerator = createAndAddDIE(dwarf::DW_TAG_enumerator, Buffer);
1413 StringRef Name = Enum.getName();
1414 addString(Enumerator, dwarf::DW_AT_name, Name);
1415 int64_t Value = Enum.getEnumValue();
1416 addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
1420 DIType DTy = resolve(CTy.getTypeDerivedFrom());
1422 addType(Buffer, DTy);
1423 addFlag(Buffer, dwarf::DW_AT_enum_class);
1427 /// constructContainingTypeDIEs - Construct DIEs for types that contain
1429 void DwarfUnit::constructContainingTypeDIEs() {
1430 for (DenseMap<DIE *, const MDNode *>::iterator CI = ContainingTypeMap.begin(),
1431 CE = ContainingTypeMap.end();
1433 DIE &SPDie = *CI->first;
1434 DIDescriptor D(CI->second);
1437 DIE *NDie = getDIE(D);
1440 addDIEEntry(SPDie, dwarf::DW_AT_containing_type, *NDie);
1444 /// constructMemberDIE - Construct member DIE from DIDerivedType.
1445 void DwarfUnit::constructMemberDIE(DIE &Buffer, DIDerivedType DT) {
1446 DIE &MemberDie = createAndAddDIE(DT.getTag(), Buffer);
1447 StringRef Name = DT.getName();
1449 addString(MemberDie, dwarf::DW_AT_name, Name);
1451 addType(MemberDie, resolve(DT.getTypeDerivedFrom()));
1453 addSourceLine(MemberDie, DT);
1455 if (DT.getTag() == dwarf::DW_TAG_inheritance && DT.isVirtual()) {
1457 // For C++, virtual base classes are not at fixed offset. Use following
1458 // expression to extract appropriate offset from vtable.
1459 // BaseAddr = ObAddr + *((*ObAddr) - Offset)
1461 DIELoc *VBaseLocationDie = new (DIEValueAllocator) DIELoc();
1462 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
1463 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1464 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1465 addUInt(*VBaseLocationDie, dwarf::DW_FORM_udata, DT.getOffsetInBits());
1466 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
1467 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1468 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
1470 addBlock(MemberDie, dwarf::DW_AT_data_member_location, VBaseLocationDie);
1472 uint64_t Size = DT.getSizeInBits();
1473 uint64_t FieldSize = getBaseTypeSize(DD, DT);
1474 uint64_t OffsetInBytes;
1476 if (Size != FieldSize) {
1477 // Handle bitfield, assume bytes are 8 bits.
1478 addUInt(MemberDie, dwarf::DW_AT_byte_size, None, FieldSize/8);
1479 addUInt(MemberDie, dwarf::DW_AT_bit_size, None, Size);
1481 uint64_t Offset = DT.getOffsetInBits();
1482 uint64_t AlignMask = ~(DT.getAlignInBits() - 1);
1483 uint64_t HiMark = (Offset + FieldSize) & AlignMask;
1484 uint64_t FieldOffset = (HiMark - FieldSize);
1485 Offset -= FieldOffset;
1487 // Maybe we need to work from the other end.
1488 if (Asm->getDataLayout().isLittleEndian())
1489 Offset = FieldSize - (Offset + Size);
1490 addUInt(MemberDie, dwarf::DW_AT_bit_offset, None, Offset);
1492 // Here DW_AT_data_member_location points to the anonymous
1493 // field that includes this bit field.
1494 OffsetInBytes = FieldOffset >> 3;
1496 // This is not a bitfield.
1497 OffsetInBytes = DT.getOffsetInBits() >> 3;
1499 if (DD->getDwarfVersion() <= 2) {
1500 DIELoc *MemLocationDie = new (DIEValueAllocator) DIELoc();
1501 addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
1502 addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes);
1503 addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie);
1505 addUInt(MemberDie, dwarf::DW_AT_data_member_location, None,
1509 if (DT.isProtected())
1510 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1511 dwarf::DW_ACCESS_protected);
1512 else if (DT.isPrivate())
1513 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1514 dwarf::DW_ACCESS_private);
1515 // Otherwise C++ member and base classes are considered public.
1516 else if (DT.isPublic())
1517 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1518 dwarf::DW_ACCESS_public);
1520 addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1,
1521 dwarf::DW_VIRTUALITY_virtual);
1523 // Objective-C properties.
1524 if (MDNode *PNode = DT.getObjCProperty())
1525 if (DIEEntry *PropertyDie = getDIEEntry(PNode))
1526 MemberDie.addValue(dwarf::DW_AT_APPLE_property, dwarf::DW_FORM_ref4,
1529 if (DT.isArtificial())
1530 addFlag(MemberDie, dwarf::DW_AT_artificial);
1533 /// getOrCreateStaticMemberDIE - Create new DIE for C++ static member.
1534 DIE *DwarfUnit::getOrCreateStaticMemberDIE(DIDerivedType DT) {
1538 // Construct the context before querying for the existence of the DIE in case
1539 // such construction creates the DIE.
1540 DIE *ContextDIE = getOrCreateContextDIE(resolve(DT.getContext()));
1541 assert(dwarf::isType(ContextDIE->getTag()) &&
1542 "Static member should belong to a type.");
1544 if (DIE *StaticMemberDIE = getDIE(DT))
1545 return StaticMemberDIE;
1547 DIE &StaticMemberDIE = createAndAddDIE(DT.getTag(), *ContextDIE, DT);
1549 DIType Ty = resolve(DT.getTypeDerivedFrom());
1551 addString(StaticMemberDIE, dwarf::DW_AT_name, DT.getName());
1552 addType(StaticMemberDIE, Ty);
1553 addSourceLine(StaticMemberDIE, DT);
1554 addFlag(StaticMemberDIE, dwarf::DW_AT_external);
1555 addFlag(StaticMemberDIE, dwarf::DW_AT_declaration);
1557 // FIXME: We could omit private if the parent is a class_type, and
1558 // public if the parent is something else.
1559 if (DT.isProtected())
1560 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1561 dwarf::DW_ACCESS_protected);
1562 else if (DT.isPrivate())
1563 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1564 dwarf::DW_ACCESS_private);
1565 else if (DT.isPublic())
1566 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1567 dwarf::DW_ACCESS_public);
1569 if (const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(DT.getConstant()))
1570 addConstantValue(StaticMemberDIE, CI, Ty);
1571 if (const ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(DT.getConstant()))
1572 addConstantFPValue(StaticMemberDIE, CFP);
1574 return &StaticMemberDIE;
1577 void DwarfUnit::emitHeader(const MCSymbol *ASectionSym) const {
1578 // Emit size of content not including length itself
1579 Asm->OutStreamer.AddComment("Length of Unit");
1580 Asm->EmitInt32(getHeaderSize() + UnitDie.getSize());
1582 Asm->OutStreamer.AddComment("DWARF version number");
1583 Asm->EmitInt16(DD->getDwarfVersion());
1584 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section");
1585 // We share one abbreviations table across all units so it's always at the
1586 // start of the section. Use a relocatable offset where needed to ensure
1587 // linking doesn't invalidate that offset.
1589 Asm->EmitSectionOffset(ASectionSym, ASectionSym);
1591 // Use a constant value when no symbol is provided.
1593 Asm->OutStreamer.AddComment("Address Size (in bytes)");
1594 Asm->EmitInt8(Asm->getDataLayout().getPointerSize());
1597 void DwarfUnit::initSection(const MCSection *Section) {
1598 assert(!this->Section);
1599 this->Section = Section;
1602 void DwarfTypeUnit::emitHeader(const MCSymbol *ASectionSym) const {
1603 DwarfUnit::emitHeader(ASectionSym);
1604 Asm->OutStreamer.AddComment("Type Signature");
1605 Asm->OutStreamer.EmitIntValue(TypeSignature, sizeof(TypeSignature));
1606 Asm->OutStreamer.AddComment("Type DIE Offset");
1607 // In a skeleton type unit there is no type DIE so emit a zero offset.
1608 Asm->OutStreamer.EmitIntValue(Ty ? Ty->getOffset() : 0,
1609 sizeof(Ty->getOffset()));
1612 bool DwarfTypeUnit::isDwoUnit() const {
1613 // Since there are no skeleton type units, all type units are dwo type units
1614 // when split DWARF is being used.
1615 return DD->useSplitDwarf();