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 "DwarfDebug.h"
17 #include "llvm/ADT/APFloat.h"
18 #include "llvm/IR/Constants.h"
19 #include "llvm/IR/DIBuilder.h"
20 #include "llvm/IR/DataLayout.h"
21 #include "llvm/IR/GlobalVariable.h"
22 #include "llvm/IR/Instructions.h"
23 #include "llvm/IR/Mangler.h"
24 #include "llvm/MC/MCAsmInfo.h"
25 #include "llvm/MC/MCContext.h"
26 #include "llvm/MC/MCSection.h"
27 #include "llvm/MC/MCStreamer.h"
28 #include "llvm/Support/CommandLine.h"
29 #include "llvm/Target/TargetFrameLowering.h"
30 #include "llvm/Target/TargetLoweringObjectFile.h"
31 #include "llvm/Target/TargetMachine.h"
32 #include "llvm/Target/TargetRegisterInfo.h"
36 #define DEBUG_TYPE "dwarfdebug"
39 GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
40 cl::desc("Generate DWARF4 type units."),
43 /// Unit - Unit constructor.
44 DwarfUnit::DwarfUnit(unsigned UID, dwarf::Tag UnitTag, DICompileUnit Node,
45 AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU)
46 : UniqueID(UID), CUNode(Node), UnitDie(UnitTag), DebugInfoOffset(0), Asm(A),
47 DD(DW), DU(DWU), IndexTyDie(nullptr), Section(nullptr),
49 assert(UnitTag == dwarf::DW_TAG_compile_unit ||
50 UnitTag == dwarf::DW_TAG_type_unit);
51 DIEIntegerOne = new (DIEValueAllocator) DIEInteger(1);
54 DwarfCompileUnit::DwarfCompileUnit(unsigned UID, DICompileUnit Node,
55 AsmPrinter *A, DwarfDebug *DW,
57 : DwarfUnit(UID, dwarf::DW_TAG_compile_unit, Node, A, DW, DWU) {
58 insertDIE(Node, &getUnitDie());
61 DwarfTypeUnit::DwarfTypeUnit(unsigned UID, DwarfCompileUnit &CU, AsmPrinter *A,
62 DwarfDebug *DW, DwarfFile *DWU,
63 MCDwarfDwoLineTable *SplitLineTable)
64 : DwarfUnit(UID, dwarf::DW_TAG_type_unit, CU.getCUNode(), A, DW, DWU),
65 CU(CU), SplitLineTable(SplitLineTable) {
67 addSectionOffset(UnitDie, dwarf::DW_AT_stmt_list, 0);
70 /// ~Unit - Destructor for compile unit.
71 DwarfUnit::~DwarfUnit() {
72 for (unsigned j = 0, M = DIEBlocks.size(); j < M; ++j)
73 DIEBlocks[j]->~DIEBlock();
74 for (unsigned j = 0, M = DIELocs.size(); j < M; ++j)
75 DIELocs[j]->~DIELoc();
78 /// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
79 /// information entry.
80 DIEEntry *DwarfUnit::createDIEEntry(DIE &Entry) {
81 DIEEntry *Value = new (DIEValueAllocator) DIEEntry(Entry);
85 /// getDefaultLowerBound - Return the default lower bound for an array. If the
86 /// DWARF version doesn't handle the language, return -1.
87 int64_t DwarfUnit::getDefaultLowerBound() const {
88 switch (getLanguage()) {
92 case dwarf::DW_LANG_C89:
93 case dwarf::DW_LANG_C99:
94 case dwarf::DW_LANG_C:
95 case dwarf::DW_LANG_C_plus_plus:
96 case dwarf::DW_LANG_ObjC:
97 case dwarf::DW_LANG_ObjC_plus_plus:
100 case dwarf::DW_LANG_Fortran77:
101 case dwarf::DW_LANG_Fortran90:
102 case dwarf::DW_LANG_Fortran95:
105 // The languages below have valid values only if the DWARF version >= 4.
106 case dwarf::DW_LANG_Java:
107 case dwarf::DW_LANG_Python:
108 case dwarf::DW_LANG_UPC:
109 case dwarf::DW_LANG_D:
110 if (dwarf::DWARF_VERSION >= 4)
114 case dwarf::DW_LANG_Ada83:
115 case dwarf::DW_LANG_Ada95:
116 case dwarf::DW_LANG_Cobol74:
117 case dwarf::DW_LANG_Cobol85:
118 case dwarf::DW_LANG_Modula2:
119 case dwarf::DW_LANG_Pascal83:
120 case dwarf::DW_LANG_PLI:
121 if (dwarf::DWARF_VERSION >= 4)
129 /// Check whether the DIE for this MDNode can be shared across CUs.
130 static bool isShareableAcrossCUs(DIDescriptor D) {
131 // When the MDNode can be part of the type system, the DIE can be shared
133 // Combining type units and cross-CU DIE sharing is lower value (since
134 // cross-CU DIE sharing is used in LTO and removes type redundancy at that
135 // level already) but may be implementable for some value in projects
136 // building multiple independent libraries with LTO and then linking those
138 return (D.isType() ||
139 (D.isSubprogram() && !DISubprogram(D).isDefinition())) &&
140 !GenerateDwarfTypeUnits;
143 /// getDIE - Returns the debug information entry map slot for the
144 /// specified debug variable. We delegate the request to DwarfDebug
145 /// when the DIE for this MDNode can be shared across CUs. The mappings
146 /// will be kept in DwarfDebug for shareable DIEs.
147 DIE *DwarfUnit::getDIE(DIDescriptor D) const {
148 if (isShareableAcrossCUs(D))
149 return DD->getDIE(D);
150 return MDNodeToDieMap.lookup(D);
153 /// insertDIE - Insert DIE into the map. 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 void DwarfUnit::insertDIE(DIDescriptor Desc, DIE *D) {
157 if (isShareableAcrossCUs(Desc)) {
158 DD->insertDIE(Desc, D);
161 MDNodeToDieMap.insert(std::make_pair(Desc, D));
164 /// addFlag - Add a flag that is true.
165 void DwarfUnit::addFlag(DIE &Die, dwarf::Attribute Attribute) {
166 if (DD->getDwarfVersion() >= 4)
167 Die.addValue(Attribute, dwarf::DW_FORM_flag_present, DIEIntegerOne);
169 Die.addValue(Attribute, dwarf::DW_FORM_flag, DIEIntegerOne);
172 /// addUInt - Add an unsigned integer attribute data and value.
174 void DwarfUnit::addUInt(DIE &Die, dwarf::Attribute Attribute,
175 Optional<dwarf::Form> Form, uint64_t Integer) {
177 Form = DIEInteger::BestForm(false, Integer);
178 DIEValue *Value = Integer == 1 ? DIEIntegerOne : new (DIEValueAllocator)
180 Die.addValue(Attribute, *Form, Value);
183 void DwarfUnit::addUInt(DIE &Block, dwarf::Form Form, uint64_t Integer) {
184 addUInt(Block, (dwarf::Attribute)0, Form, Integer);
187 /// addSInt - Add an signed integer attribute data and value.
189 void DwarfUnit::addSInt(DIE &Die, dwarf::Attribute Attribute,
190 Optional<dwarf::Form> Form, int64_t Integer) {
192 Form = DIEInteger::BestForm(true, Integer);
193 DIEValue *Value = new (DIEValueAllocator) DIEInteger(Integer);
194 Die.addValue(Attribute, *Form, Value);
197 void DwarfUnit::addSInt(DIELoc &Die, Optional<dwarf::Form> Form,
199 addSInt(Die, (dwarf::Attribute)0, Form, Integer);
202 /// addString - Add a string attribute data and value. We always emit a
203 /// reference to the string pool instead of immediate strings so that DIEs have
204 /// more predictable sizes. In the case of split dwarf we emit an index
205 /// into another table which gets us the static offset into the string
207 void DwarfUnit::addString(DIE &Die, dwarf::Attribute Attribute,
210 if (!DD->useSplitDwarf())
211 return addLocalString(Die, Attribute, String);
213 unsigned idx = DU->getStringPool().getIndex(*Asm, String);
214 DIEValue *Value = new (DIEValueAllocator) DIEInteger(idx);
215 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
216 Die.addValue(Attribute, dwarf::DW_FORM_GNU_str_index, Str);
219 /// addLocalString - Add a string attribute data and value. This is guaranteed
220 /// to be in the local string pool instead of indirected.
221 void DwarfUnit::addLocalString(DIE &Die, dwarf::Attribute Attribute,
223 MCSymbol *Symb = DU->getStringPool().getSymbol(*Asm, String);
225 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
226 Value = new (DIEValueAllocator) DIELabel(Symb);
228 MCSymbol *StringPool = DU->getStringPool().getSectionSymbol();
229 Value = new (DIEValueAllocator) DIEDelta(Symb, StringPool);
231 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
232 Die.addValue(Attribute, dwarf::DW_FORM_strp, Str);
235 /// addExpr - Add a Dwarf expression attribute data and value.
237 void DwarfUnit::addExpr(DIELoc &Die, dwarf::Form Form, const MCExpr *Expr) {
238 DIEValue *Value = new (DIEValueAllocator) DIEExpr(Expr);
239 Die.addValue((dwarf::Attribute)0, Form, Value);
242 /// addLocationList - Add a Dwarf loclistptr attribute data and value.
244 void DwarfUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute,
246 DIEValue *Value = new (DIEValueAllocator) DIELocList(Index);
247 dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
248 : dwarf::DW_FORM_data4;
249 Die.addValue(Attribute, Form, Value);
252 /// addLabel - Add a Dwarf label attribute data and value.
254 void DwarfUnit::addLabel(DIE &Die, dwarf::Attribute Attribute, dwarf::Form Form,
255 const MCSymbol *Label) {
256 DIEValue *Value = new (DIEValueAllocator) DIELabel(Label);
257 Die.addValue(Attribute, Form, Value);
260 void DwarfUnit::addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label) {
261 addLabel(Die, (dwarf::Attribute)0, Form, Label);
264 /// addSectionLabel - Add a Dwarf section label attribute data and value.
266 void DwarfUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute,
267 const MCSymbol *Label) {
268 if (DD->getDwarfVersion() >= 4)
269 addLabel(Die, Attribute, dwarf::DW_FORM_sec_offset, Label);
271 addLabel(Die, Attribute, dwarf::DW_FORM_data4, Label);
274 /// addSectionOffset - Add an offset into a section attribute data and value.
276 void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
278 if (DD->getDwarfVersion() >= 4)
279 addUInt(Die, Attribute, dwarf::DW_FORM_sec_offset, Integer);
281 addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
284 /// addLabelAddress - Add a dwarf label attribute data and value using
285 /// DW_FORM_addr or DW_FORM_GNU_addr_index.
287 void DwarfCompileUnit::addLabelAddress(DIE &Die, dwarf::Attribute Attribute,
288 const MCSymbol *Label) {
290 if (!DD->useSplitDwarf())
291 return addLocalLabelAddress(Die, Attribute, Label);
294 DD->addArangeLabel(SymbolCU(this, Label));
296 unsigned idx = DD->getAddressPool().getIndex(Label);
297 DIEValue *Value = new (DIEValueAllocator) DIEInteger(idx);
298 Die.addValue(Attribute, dwarf::DW_FORM_GNU_addr_index, Value);
301 void DwarfCompileUnit::addLocalLabelAddress(DIE &Die,
302 dwarf::Attribute Attribute,
303 const MCSymbol *Label) {
305 DD->addArangeLabel(SymbolCU(this, Label));
307 Die.addValue(Attribute, dwarf::DW_FORM_addr,
308 Label ? (DIEValue *)new (DIEValueAllocator) DIELabel(Label)
309 : new (DIEValueAllocator) DIEInteger(0));
312 unsigned DwarfCompileUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
313 // If we print assembly, we can't separate .file entries according to
314 // compile units. Thus all files will belong to the default compile unit.
316 // FIXME: add a better feature test than hasRawTextSupport. Even better,
317 // extend .file to support this.
318 return Asm->OutStreamer.EmitDwarfFileDirective(
319 0, DirName, FileName,
320 Asm->OutStreamer.hasRawTextSupport() ? 0 : getUniqueID());
323 unsigned DwarfTypeUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
324 return SplitLineTable ? SplitLineTable->getFile(DirName, FileName)
325 : getCU().getOrCreateSourceID(FileName, DirName);
328 /// addOpAddress - Add a dwarf op address data and value using the
329 /// form given and an op of either DW_FORM_addr or DW_FORM_GNU_addr_index.
331 void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) {
332 if (!DD->useSplitDwarf()) {
333 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
334 addLabel(Die, dwarf::DW_FORM_udata, Sym);
336 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_addr_index);
337 addUInt(Die, dwarf::DW_FORM_GNU_addr_index,
338 DD->getAddressPool().getIndex(Sym));
342 /// addSectionDelta - Add a section label delta attribute data and value.
344 void DwarfUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
345 const MCSymbol *Hi, const MCSymbol *Lo) {
346 DIEValue *Value = new (DIEValueAllocator) DIEDelta(Hi, Lo);
347 Die.addValue(Attribute, DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
348 : dwarf::DW_FORM_data4,
352 void DwarfUnit::addLabelDelta(DIE &Die, dwarf::Attribute Attribute,
353 const MCSymbol *Hi, const MCSymbol *Lo) {
354 DIEValue *Value = new (DIEValueAllocator) DIEDelta(Hi, Lo);
355 Die.addValue(Attribute, dwarf::DW_FORM_data4, Value);
358 /// addDIEEntry - Add a DIE attribute data and value.
360 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry) {
361 addDIEEntry(Die, Attribute, createDIEEntry(Entry));
364 void DwarfUnit::addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type) {
365 // Flag the type unit reference as a declaration so that if it contains
366 // members (implicit special members, static data member definitions, member
367 // declarations for definitions in this CU, etc) consumers don't get confused
368 // and think this is a full definition.
369 addFlag(Die, dwarf::DW_AT_declaration);
371 Die.addValue(dwarf::DW_AT_signature, dwarf::DW_FORM_ref_sig8,
372 new (DIEValueAllocator) DIETypeSignature(Type));
375 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
377 const DIE *DieCU = Die.getUnitOrNull();
378 const DIE *EntryCU = Entry->getEntry().getUnitOrNull();
380 // We assume that Die belongs to this CU, if it is not linked to any CU yet.
381 DieCU = &getUnitDie();
383 EntryCU = &getUnitDie();
384 Die.addValue(Attribute,
385 EntryCU == DieCU ? dwarf::DW_FORM_ref4 : dwarf::DW_FORM_ref_addr,
389 /// Create a DIE with the given Tag, add the DIE to its parent, and
390 /// call insertDIE if MD is not null.
391 DIE &DwarfUnit::createAndAddDIE(unsigned Tag, DIE &Parent, DIDescriptor N) {
392 assert(Tag != dwarf::DW_TAG_auto_variable &&
393 Tag != dwarf::DW_TAG_arg_variable);
394 Parent.addChild(make_unique<DIE>((dwarf::Tag)Tag));
395 DIE &Die = *Parent.getChildren().back();
401 /// addBlock - Add block data.
403 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Loc) {
404 Loc->ComputeSize(Asm);
405 DIELocs.push_back(Loc); // Memoize so we can call the destructor later on.
406 Die.addValue(Attribute, Loc->BestForm(DD->getDwarfVersion()), Loc);
409 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute,
411 Block->ComputeSize(Asm);
412 DIEBlocks.push_back(Block); // Memoize so we can call the destructor later on.
413 Die.addValue(Attribute, Block->BestForm(), Block);
416 /// addSourceLine - Add location information to specified debug information
418 void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, StringRef File,
419 StringRef Directory) {
423 unsigned FileID = getOrCreateSourceID(File, Directory);
424 assert(FileID && "Invalid file id");
425 addUInt(Die, dwarf::DW_AT_decl_file, None, FileID);
426 addUInt(Die, dwarf::DW_AT_decl_line, None, Line);
429 /// addSourceLine - Add location information to specified debug information
431 void DwarfUnit::addSourceLine(DIE &Die, DIVariable V) {
432 assert(V.isVariable());
434 addSourceLine(Die, V.getLineNumber(), V.getContext().getFilename(),
435 V.getContext().getDirectory());
438 /// addSourceLine - Add location information to specified debug information
440 void DwarfUnit::addSourceLine(DIE &Die, DIGlobalVariable G) {
441 assert(G.isGlobalVariable());
443 addSourceLine(Die, G.getLineNumber(), G.getFilename(), G.getDirectory());
446 /// addSourceLine - Add location information to specified debug information
448 void DwarfUnit::addSourceLine(DIE &Die, DISubprogram SP) {
449 assert(SP.isSubprogram());
451 addSourceLine(Die, SP.getLineNumber(), SP.getFilename(), SP.getDirectory());
454 /// addSourceLine - Add location information to specified debug information
456 void DwarfUnit::addSourceLine(DIE &Die, DIType Ty) {
459 addSourceLine(Die, Ty.getLineNumber(), Ty.getFilename(), Ty.getDirectory());
462 /// addSourceLine - Add location information to specified debug information
464 void DwarfUnit::addSourceLine(DIE &Die, DIObjCProperty Ty) {
465 assert(Ty.isObjCProperty());
467 DIFile File = Ty.getFile();
468 addSourceLine(Die, Ty.getLineNumber(), File.getFilename(),
469 File.getDirectory());
472 /// addSourceLine - Add location information to specified debug information
474 void DwarfUnit::addSourceLine(DIE &Die, DINameSpace NS) {
477 addSourceLine(Die, NS.getLineNumber(), NS.getFilename(), NS.getDirectory());
480 /// addVariableAddress - Add DW_AT_location attribute for a
481 /// DbgVariable based on provided MachineLocation.
482 void DwarfUnit::addVariableAddress(const DbgVariable &DV, DIE &Die,
483 MachineLocation Location) {
484 if (DV.variableHasComplexAddress())
485 addComplexAddress(DV, Die, dwarf::DW_AT_location, Location);
486 else if (DV.isBlockByrefVariable())
487 addBlockByrefAddress(DV, Die, dwarf::DW_AT_location, Location);
489 addAddress(Die, dwarf::DW_AT_location, Location,
490 DV.getVariable().isIndirect());
493 /// addRegisterOp - Add register operand.
494 void DwarfUnit::addRegisterOp(DIELoc &TheDie, unsigned Reg) {
495 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
496 int DWReg = RI->getDwarfRegNum(Reg, false);
497 bool isSubRegister = DWReg < 0;
501 // Go up the super-register chain until we hit a valid dwarf register number.
502 for (MCSuperRegIterator SR(Reg, RI); SR.isValid() && DWReg < 0; ++SR) {
503 DWReg = RI->getDwarfRegNum(*SR, false);
505 Idx = RI->getSubRegIndex(*SR, Reg);
509 DEBUG(dbgs() << "Invalid Dwarf register number.\n");
510 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_nop);
516 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_reg0 + DWReg);
518 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_regx);
519 addUInt(TheDie, dwarf::DW_FORM_udata, DWReg);
524 unsigned Size = RI->getSubRegIdxSize(Idx);
525 unsigned Offset = RI->getSubRegIdxOffset(Idx);
527 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_bit_piece);
528 addUInt(TheDie, dwarf::DW_FORM_data1, Size);
529 addUInt(TheDie, dwarf::DW_FORM_data1, Offset);
531 unsigned ByteSize = Size / 8; // Assuming 8 bits per byte.
532 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_piece);
533 addUInt(TheDie, dwarf::DW_FORM_data1, ByteSize);
538 /// addRegisterOffset - Add register offset.
539 void DwarfUnit::addRegisterOffset(DIELoc &TheDie, unsigned Reg,
541 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
542 unsigned DWReg = RI->getDwarfRegNum(Reg, false);
543 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo();
544 if (Reg == TRI->getFrameRegister(*Asm->MF))
545 // If variable offset is based in frame register then use fbreg.
546 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_fbreg);
548 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + DWReg);
550 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_bregx);
551 addUInt(TheDie, dwarf::DW_FORM_udata, DWReg);
553 addSInt(TheDie, dwarf::DW_FORM_sdata, Offset);
556 /// addAddress - Add an address attribute to a die based on the location
558 void DwarfUnit::addAddress(DIE &Die, dwarf::Attribute Attribute,
559 const MachineLocation &Location, bool Indirect) {
560 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
562 if (Location.isReg() && !Indirect)
563 addRegisterOp(*Loc, Location.getReg());
565 addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
566 if (Indirect && !Location.isReg()) {
567 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
571 // Now attach the location information to the DIE.
572 addBlock(Die, Attribute, Loc);
575 /// addComplexAddress - Start with the address based on the location provided,
576 /// and generate the DWARF information necessary to find the actual variable
577 /// given the extra address information encoded in the DbgVariable, starting
578 /// from the starting location. Add the DWARF information to the die.
580 void DwarfUnit::addComplexAddress(const DbgVariable &DV, DIE &Die,
581 dwarf::Attribute Attribute,
582 const MachineLocation &Location) {
583 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
584 unsigned N = DV.getNumAddrElements();
586 if (Location.isReg()) {
587 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
588 // If first address element is OpPlus then emit
589 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
590 addRegisterOffset(*Loc, Location.getReg(), DV.getAddrElement(1));
593 addRegisterOp(*Loc, Location.getReg());
595 addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
598 uint64_t Element = DV.getAddrElement(i);
599 if (Element == DIBuilder::OpPlus) {
600 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
601 addUInt(*Loc, dwarf::DW_FORM_udata, DV.getAddrElement(++i));
602 } else if (Element == DIBuilder::OpDeref) {
603 if (!Location.isReg())
604 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
606 llvm_unreachable("unknown DIBuilder Opcode");
609 // Now attach the location information to the DIE.
610 addBlock(Die, Attribute, Loc);
613 /* Byref variables, in Blocks, are declared by the programmer as "SomeType
614 VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
615 gives the variable VarName either the struct, or a pointer to the struct, as
616 its type. This is necessary for various behind-the-scenes things the
617 compiler needs to do with by-reference variables in Blocks.
619 However, as far as the original *programmer* is concerned, the variable
620 should still have type 'SomeType', as originally declared.
622 The function getBlockByrefType dives into the __Block_byref_x_VarName
623 struct to find the original type of the variable, which is then assigned to
624 the variable's Debug Information Entry as its real type. So far, so good.
625 However now the debugger will expect the variable VarName to have the type
626 SomeType. So we need the location attribute for the variable to be an
627 expression that explains to the debugger how to navigate through the
628 pointers and struct to find the actual variable of type SomeType.
630 The following function does just that. We start by getting
631 the "normal" location for the variable. This will be the location
632 of either the struct __Block_byref_x_VarName or the pointer to the
633 struct __Block_byref_x_VarName.
635 The struct will look something like:
637 struct __Block_byref_x_VarName {
639 struct __Block_byref_x_VarName *forwarding;
640 ... <various other fields>
642 ... <maybe more fields>
645 If we are given the struct directly (as our starting point) we
646 need to tell the debugger to:
648 1). Add the offset of the forwarding field.
650 2). Follow that pointer to get the real __Block_byref_x_VarName
651 struct to use (the real one may have been copied onto the heap).
653 3). Add the offset for the field VarName, to find the actual variable.
655 If we started with a pointer to the struct, then we need to
656 dereference that pointer first, before the other steps.
657 Translating this into DWARF ops, we will need to append the following
658 to the current location description for the variable:
660 DW_OP_deref -- optional, if we start with a pointer
661 DW_OP_plus_uconst <forward_fld_offset>
663 DW_OP_plus_uconst <varName_fld_offset>
665 That is what this function does. */
667 /// addBlockByrefAddress - Start with the address based on the location
668 /// provided, and generate the DWARF information necessary to find the
669 /// actual Block variable (navigating the Block struct) based on the
670 /// starting location. Add the DWARF information to the die. For
671 /// more information, read large comment just above here.
673 void DwarfUnit::addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
674 dwarf::Attribute Attribute,
675 const MachineLocation &Location) {
676 DIType Ty = DV.getType();
678 uint16_t Tag = Ty.getTag();
679 bool isPointer = false;
681 StringRef varName = DV.getName();
683 if (Tag == dwarf::DW_TAG_pointer_type) {
684 DIDerivedType DTy(Ty);
685 TmpTy = resolve(DTy.getTypeDerivedFrom());
689 DICompositeType blockStruct(TmpTy);
691 // Find the __forwarding field and the variable field in the __Block_byref
693 DIArray Fields = blockStruct.getTypeArray();
694 DIDerivedType varField;
695 DIDerivedType forwardingField;
697 for (unsigned i = 0, N = Fields.getNumElements(); i < N; ++i) {
698 DIDerivedType DT(Fields.getElement(i));
699 StringRef fieldName = DT.getName();
700 if (fieldName == "__forwarding")
701 forwardingField = DT;
702 else if (fieldName == varName)
706 // Get the offsets for the forwarding field and the variable field.
707 unsigned forwardingFieldOffset = forwardingField.getOffsetInBits() >> 3;
708 unsigned varFieldOffset = varField.getOffsetInBits() >> 2;
710 // Decode the original location, and use that as the start of the byref
711 // variable's location.
712 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
714 if (Location.isReg())
715 addRegisterOp(*Loc, Location.getReg());
717 addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
719 // If we started with a pointer to the __Block_byref... struct, then
720 // the first thing we need to do is dereference the pointer (DW_OP_deref).
722 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
724 // Next add the offset for the '__forwarding' field:
725 // DW_OP_plus_uconst ForwardingFieldOffset. Note there's no point in
726 // adding the offset if it's 0.
727 if (forwardingFieldOffset > 0) {
728 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
729 addUInt(*Loc, dwarf::DW_FORM_udata, forwardingFieldOffset);
732 // Now dereference the __forwarding field to get to the real __Block_byref
733 // struct: DW_OP_deref.
734 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
736 // Now that we've got the real __Block_byref... struct, add the offset
737 // for the variable's field to get to the location of the actual variable:
738 // DW_OP_plus_uconst varFieldOffset. Again, don't add if it's 0.
739 if (varFieldOffset > 0) {
740 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
741 addUInt(*Loc, dwarf::DW_FORM_udata, varFieldOffset);
744 // Now attach the location information to the DIE.
745 addBlock(Die, Attribute, Loc);
748 /// Return true if type encoding is unsigned.
749 static bool isUnsignedDIType(DwarfDebug *DD, DIType Ty) {
750 DIDerivedType DTy(Ty);
751 if (DTy.isDerivedType()) {
752 dwarf::Tag T = (dwarf::Tag)Ty.getTag();
753 // Encode pointer constants as unsigned bytes. This is used at least for
754 // null pointer constant emission.
755 // FIXME: reference and rvalue_reference /probably/ shouldn't be allowed
756 // here, but accept them for now due to a bug in SROA producing bogus
758 if (T == dwarf::DW_TAG_pointer_type ||
759 T == dwarf::DW_TAG_ptr_to_member_type ||
760 T == dwarf::DW_TAG_reference_type ||
761 T == dwarf::DW_TAG_rvalue_reference_type)
763 assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
764 T == dwarf::DW_TAG_volatile_type ||
765 T == dwarf::DW_TAG_restrict_type ||
766 T == dwarf::DW_TAG_enumeration_type);
767 if (DITypeRef Deriv = DTy.getTypeDerivedFrom())
768 return isUnsignedDIType(DD, DD->resolve(Deriv));
769 // FIXME: Enums without a fixed underlying type have unknown signedness
770 // here, leading to incorrectly emitted constants.
771 assert(DTy.getTag() == dwarf::DW_TAG_enumeration_type);
776 assert(BTy.isBasicType());
777 unsigned Encoding = BTy.getEncoding();
778 assert((Encoding == dwarf::DW_ATE_unsigned ||
779 Encoding == dwarf::DW_ATE_unsigned_char ||
780 Encoding == dwarf::DW_ATE_signed ||
781 Encoding == dwarf::DW_ATE_signed_char ||
782 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean) &&
783 "Unsupported encoding");
784 return (Encoding == dwarf::DW_ATE_unsigned ||
785 Encoding == dwarf::DW_ATE_unsigned_char ||
786 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean);
789 /// If this type is derived from a base type then return base type size.
790 static uint64_t getBaseTypeSize(DwarfDebug *DD, DIDerivedType Ty) {
791 unsigned Tag = Ty.getTag();
793 if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
794 Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
795 Tag != dwarf::DW_TAG_restrict_type)
796 return Ty.getSizeInBits();
798 DIType BaseType = DD->resolve(Ty.getTypeDerivedFrom());
800 // If this type is not derived from any type or the type is a declaration then
801 // take conservative approach.
802 if (!BaseType.isValid() || BaseType.isForwardDecl())
803 return Ty.getSizeInBits();
805 // If this is a derived type, go ahead and get the base type, unless it's a
806 // reference then it's just the size of the field. Pointer types have no need
807 // of this since they're a different type of qualification on the type.
808 if (BaseType.getTag() == dwarf::DW_TAG_reference_type ||
809 BaseType.getTag() == dwarf::DW_TAG_rvalue_reference_type)
810 return Ty.getSizeInBits();
812 if (BaseType.isDerivedType())
813 return getBaseTypeSize(DD, DIDerivedType(BaseType));
815 return BaseType.getSizeInBits();
818 /// addConstantFPValue - Add constant value entry in variable DIE.
819 void DwarfUnit::addConstantFPValue(DIE &Die, const MachineOperand &MO) {
820 assert(MO.isFPImm() && "Invalid machine operand!");
821 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
822 APFloat FPImm = MO.getFPImm()->getValueAPF();
824 // Get the raw data form of the floating point.
825 const APInt FltVal = FPImm.bitcastToAPInt();
826 const char *FltPtr = (const char *)FltVal.getRawData();
828 int NumBytes = FltVal.getBitWidth() / 8; // 8 bits per byte.
829 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
830 int Incr = (LittleEndian ? 1 : -1);
831 int Start = (LittleEndian ? 0 : NumBytes - 1);
832 int Stop = (LittleEndian ? NumBytes : -1);
834 // Output the constant to DWARF one byte at a time.
835 for (; Start != Stop; Start += Incr)
836 addUInt(*Block, dwarf::DW_FORM_data1, (unsigned char)0xFF & FltPtr[Start]);
838 addBlock(Die, dwarf::DW_AT_const_value, Block);
841 /// addConstantFPValue - Add constant value entry in variable DIE.
842 void DwarfUnit::addConstantFPValue(DIE &Die, const ConstantFP *CFP) {
843 // Pass this down to addConstantValue as an unsigned bag of bits.
844 addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
847 /// addConstantValue - Add constant value entry in variable DIE.
848 void DwarfUnit::addConstantValue(DIE &Die, const ConstantInt *CI, DIType Ty) {
849 addConstantValue(Die, CI->getValue(), Ty);
852 /// addConstantValue - Add constant value entry in variable DIE.
853 void DwarfUnit::addConstantValue(DIE &Die, const MachineOperand &MO,
855 assert(MO.isImm() && "Invalid machine operand!");
857 addConstantValue(Die, isUnsignedDIType(DD, Ty), MO.getImm());
860 void DwarfUnit::addConstantValue(DIE &Die, bool Unsigned, uint64_t Val) {
861 // FIXME: This is a bit conservative/simple - it emits negative values always
862 // sign extended to 64 bits rather than minimizing the number of bytes.
863 addUInt(Die, dwarf::DW_AT_const_value,
864 Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata, Val);
867 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, DIType Ty) {
868 addConstantValue(Die, Val, isUnsignedDIType(DD, Ty));
871 // addConstantValue - Add constant value entry in variable DIE.
872 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
873 unsigned CIBitWidth = Val.getBitWidth();
874 if (CIBitWidth <= 64) {
875 addConstantValue(Die, Unsigned,
876 Unsigned ? Val.getZExtValue() : Val.getSExtValue());
880 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
882 // Get the raw data form of the large APInt.
883 const uint64_t *Ptr64 = Val.getRawData();
885 int NumBytes = Val.getBitWidth() / 8; // 8 bits per byte.
886 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
888 // Output the constant to DWARF one byte at a time.
889 for (int i = 0; i < NumBytes; i++) {
892 c = Ptr64[i / 8] >> (8 * (i & 7));
894 c = Ptr64[(NumBytes - 1 - i) / 8] >> (8 * ((NumBytes - 1 - i) & 7));
895 addUInt(*Block, dwarf::DW_FORM_data1, c);
898 addBlock(Die, dwarf::DW_AT_const_value, Block);
901 /// addTemplateParams - Add template parameters into buffer.
902 void DwarfUnit::addTemplateParams(DIE &Buffer, DIArray TParams) {
903 // Add template parameters.
904 for (unsigned i = 0, e = TParams.getNumElements(); i != e; ++i) {
905 DIDescriptor Element = TParams.getElement(i);
906 if (Element.isTemplateTypeParameter())
907 constructTemplateTypeParameterDIE(Buffer,
908 DITemplateTypeParameter(Element));
909 else if (Element.isTemplateValueParameter())
910 constructTemplateValueParameterDIE(Buffer,
911 DITemplateValueParameter(Element));
915 /// getOrCreateContextDIE - Get context owner's DIE.
916 DIE *DwarfUnit::getOrCreateContextDIE(DIScope Context) {
917 if (!Context || Context.isFile())
918 return &getUnitDie();
919 if (Context.isType())
920 return getOrCreateTypeDIE(DIType(Context));
921 if (Context.isNameSpace())
922 return getOrCreateNameSpace(DINameSpace(Context));
923 if (Context.isSubprogram())
924 return getOrCreateSubprogramDIE(DISubprogram(Context));
925 return getDIE(Context);
928 DIE *DwarfUnit::createTypeDIE(DICompositeType Ty) {
929 DIScope Context = resolve(Ty.getContext());
930 DIE *ContextDIE = getOrCreateContextDIE(Context);
932 if (DIE *TyDIE = getDIE(Ty))
936 DIE &TyDIE = createAndAddDIE(Ty.getTag(), *ContextDIE, Ty);
938 constructTypeDIE(TyDIE, Ty);
940 updateAcceleratorTables(Context, Ty, TyDIE);
944 /// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
946 DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
952 assert(Ty == resolve(Ty.getRef()) &&
953 "type was not uniqued, possible ODR violation.");
955 // DW_TAG_restrict_type is not supported in DWARF2
956 if (Ty.getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
957 return getOrCreateTypeDIE(resolve(DIDerivedType(Ty).getTypeDerivedFrom()));
959 // Construct the context before querying for the existence of the DIE in case
960 // such construction creates the DIE.
961 DIScope Context = resolve(Ty.getContext());
962 DIE *ContextDIE = getOrCreateContextDIE(Context);
965 if (DIE *TyDIE = getDIE(Ty))
969 DIE &TyDIE = createAndAddDIE(Ty.getTag(), *ContextDIE, Ty);
971 updateAcceleratorTables(Context, Ty, TyDIE);
973 if (Ty.isBasicType())
974 constructTypeDIE(TyDIE, DIBasicType(Ty));
975 else if (Ty.isCompositeType()) {
976 DICompositeType CTy(Ty);
977 if (GenerateDwarfTypeUnits && !Ty.isForwardDecl())
978 if (MDString *TypeId = CTy.getIdentifier()) {
979 DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);
980 // Skip updating the accelerator tables since this is not the full type.
983 constructTypeDIE(TyDIE, CTy);
985 assert(Ty.isDerivedType() && "Unknown kind of DIType");
986 constructTypeDIE(TyDIE, DIDerivedType(Ty));
992 void DwarfUnit::updateAcceleratorTables(DIScope Context, DIType Ty,
994 if (!Ty.getName().empty() && !Ty.isForwardDecl()) {
995 bool IsImplementation = 0;
996 if (Ty.isCompositeType()) {
997 DICompositeType CT(Ty);
998 // A runtime language of 0 actually means C/C++ and that any
999 // non-negative value is some version of Objective-C/C++.
1000 IsImplementation = (CT.getRunTimeLang() == 0) || CT.isObjcClassComplete();
1002 unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
1003 DD->addAccelType(Ty.getName(), TyDIE, Flags);
1005 if ((!Context || Context.isCompileUnit() || Context.isFile() ||
1006 Context.isNameSpace()) &&
1007 getCUNode().getEmissionKind() != DIBuilder::LineTablesOnly)
1008 GlobalTypes[getParentContextString(Context) + Ty.getName().str()] =
1013 /// addType - Add a new type attribute to the specified entity.
1014 void DwarfUnit::addType(DIE &Entity, DIType Ty, dwarf::Attribute Attribute) {
1015 assert(Ty && "Trying to add a type that doesn't exist?");
1017 // Check for pre-existence.
1018 DIEEntry *Entry = getDIEEntry(Ty);
1019 // If it exists then use the existing value.
1021 addDIEEntry(Entity, Attribute, Entry);
1026 DIE *Buffer = getOrCreateTypeDIE(Ty);
1029 Entry = createDIEEntry(*Buffer);
1030 insertDIEEntry(Ty, Entry);
1031 addDIEEntry(Entity, Attribute, Entry);
1034 /// addGlobalName - Add a new global name to the compile unit.
1035 void DwarfUnit::addGlobalName(StringRef Name, DIE &Die, DIScope Context) {
1036 if (getCUNode().getEmissionKind() == DIBuilder::LineTablesOnly)
1038 std::string FullName = getParentContextString(Context) + Name.str();
1039 GlobalNames[FullName] = &Die;
1042 /// getParentContextString - Walks the metadata parent chain in a language
1043 /// specific manner (using the compile unit language) and returns
1044 /// it as a string. This is done at the metadata level because DIEs may
1045 /// not currently have been added to the parent context and walking the
1046 /// DIEs looking for names is more expensive than walking the metadata.
1047 std::string DwarfUnit::getParentContextString(DIScope Context) const {
1051 // FIXME: Decide whether to implement this for non-C++ languages.
1052 if (getLanguage() != dwarf::DW_LANG_C_plus_plus)
1056 SmallVector<DIScope, 1> Parents;
1057 while (!Context.isCompileUnit()) {
1058 Parents.push_back(Context);
1059 if (Context.getContext())
1060 Context = resolve(Context.getContext());
1062 // Structure, etc types will have a NULL context if they're at the top
1067 // Reverse iterate over our list to go from the outermost construct to the
1069 for (SmallVectorImpl<DIScope>::reverse_iterator I = Parents.rbegin(),
1073 StringRef Name = Ctx.getName();
1074 if (!Name.empty()) {
1082 /// constructTypeDIE - Construct basic type die from DIBasicType.
1083 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIBasicType BTy) {
1084 // Get core information.
1085 StringRef Name = BTy.getName();
1086 // Add name if not anonymous or intermediate type.
1088 addString(Buffer, dwarf::DW_AT_name, Name);
1090 // An unspecified type only has a name attribute.
1091 if (BTy.getTag() == dwarf::DW_TAG_unspecified_type)
1094 addUInt(Buffer, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
1097 uint64_t Size = BTy.getSizeInBits() >> 3;
1098 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
1101 /// constructTypeDIE - Construct derived type die from DIDerivedType.
1102 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIDerivedType DTy) {
1103 // Get core information.
1104 StringRef Name = DTy.getName();
1105 uint64_t Size = DTy.getSizeInBits() >> 3;
1106 uint16_t Tag = Buffer.getTag();
1108 // Map to main type, void will not have a type.
1109 DIType FromTy = resolve(DTy.getTypeDerivedFrom());
1111 addType(Buffer, FromTy);
1113 // Add name if not anonymous or intermediate type.
1115 addString(Buffer, dwarf::DW_AT_name, Name);
1117 // Add size if non-zero (derived types might be zero-sized.)
1118 if (Size && Tag != dwarf::DW_TAG_pointer_type)
1119 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
1121 if (Tag == dwarf::DW_TAG_ptr_to_member_type)
1122 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
1123 *getOrCreateTypeDIE(resolve(DTy.getClassType())));
1124 // Add source line info if available and TyDesc is not a forward declaration.
1125 if (!DTy.isForwardDecl())
1126 addSourceLine(Buffer, DTy);
1129 /// constructSubprogramArguments - Construct function argument DIEs.
1130 void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DIArray Args) {
1131 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) {
1132 DIDescriptor Ty = Args.getElement(i);
1133 if (Ty.isUnspecifiedParameter()) {
1134 assert(i == N-1 && "Unspecified parameter must be the last argument");
1135 createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
1137 DIE &Arg = createAndAddDIE(dwarf::DW_TAG_formal_parameter, Buffer);
1138 addType(Arg, DIType(Ty));
1139 if (DIType(Ty).isArtificial())
1140 addFlag(Arg, dwarf::DW_AT_artificial);
1145 /// constructTypeDIE - Construct type DIE from DICompositeType.
1146 void DwarfUnit::constructTypeDIE(DIE &Buffer, DICompositeType CTy) {
1147 // Add name if not anonymous or intermediate type.
1148 StringRef Name = CTy.getName();
1150 uint64_t Size = CTy.getSizeInBits() >> 3;
1151 uint16_t Tag = Buffer.getTag();
1154 case dwarf::DW_TAG_array_type:
1155 constructArrayTypeDIE(Buffer, CTy);
1157 case dwarf::DW_TAG_enumeration_type:
1158 constructEnumTypeDIE(Buffer, CTy);
1160 case dwarf::DW_TAG_subroutine_type: {
1161 // Add return type. A void return won't have a type.
1162 DIArray Elements = CTy.getTypeArray();
1163 DIType RTy(Elements.getElement(0));
1165 addType(Buffer, RTy);
1167 bool isPrototyped = true;
1168 if (Elements.getNumElements() == 2 &&
1169 Elements.getElement(1).isUnspecifiedParameter())
1170 isPrototyped = false;
1172 constructSubprogramArguments(Buffer, Elements);
1174 // Add prototype flag if we're dealing with a C language and the
1175 // function has been prototyped.
1176 uint16_t Language = getLanguage();
1178 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1179 Language == dwarf::DW_LANG_ObjC))
1180 addFlag(Buffer, dwarf::DW_AT_prototyped);
1182 if (CTy.isLValueReference())
1183 addFlag(Buffer, dwarf::DW_AT_reference);
1185 if (CTy.isRValueReference())
1186 addFlag(Buffer, dwarf::DW_AT_rvalue_reference);
1188 case dwarf::DW_TAG_structure_type:
1189 case dwarf::DW_TAG_union_type:
1190 case dwarf::DW_TAG_class_type: {
1191 // Add elements to structure type.
1192 DIArray Elements = CTy.getTypeArray();
1193 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1194 DIDescriptor Element = Elements.getElement(i);
1195 if (Element.isSubprogram())
1196 getOrCreateSubprogramDIE(DISubprogram(Element));
1197 else if (Element.isDerivedType()) {
1198 DIDerivedType DDTy(Element);
1199 if (DDTy.getTag() == dwarf::DW_TAG_friend) {
1200 DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
1201 addType(ElemDie, resolve(DDTy.getTypeDerivedFrom()),
1202 dwarf::DW_AT_friend);
1203 } else if (DDTy.isStaticMember()) {
1204 getOrCreateStaticMemberDIE(DDTy);
1206 constructMemberDIE(Buffer, DDTy);
1208 } else if (Element.isObjCProperty()) {
1209 DIObjCProperty Property(Element);
1210 DIE &ElemDie = createAndAddDIE(Property.getTag(), Buffer);
1211 StringRef PropertyName = Property.getObjCPropertyName();
1212 addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
1213 if (Property.getType())
1214 addType(ElemDie, Property.getType());
1215 addSourceLine(ElemDie, Property);
1216 StringRef GetterName = Property.getObjCPropertyGetterName();
1217 if (!GetterName.empty())
1218 addString(ElemDie, dwarf::DW_AT_APPLE_property_getter, GetterName);
1219 StringRef SetterName = Property.getObjCPropertySetterName();
1220 if (!SetterName.empty())
1221 addString(ElemDie, dwarf::DW_AT_APPLE_property_setter, SetterName);
1222 unsigned PropertyAttributes = 0;
1223 if (Property.isReadOnlyObjCProperty())
1224 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_readonly;
1225 if (Property.isReadWriteObjCProperty())
1226 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_readwrite;
1227 if (Property.isAssignObjCProperty())
1228 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_assign;
1229 if (Property.isRetainObjCProperty())
1230 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_retain;
1231 if (Property.isCopyObjCProperty())
1232 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_copy;
1233 if (Property.isNonAtomicObjCProperty())
1234 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_nonatomic;
1235 if (PropertyAttributes)
1236 addUInt(ElemDie, dwarf::DW_AT_APPLE_property_attribute, None,
1237 PropertyAttributes);
1239 DIEEntry *Entry = getDIEEntry(Element);
1241 Entry = createDIEEntry(ElemDie);
1242 insertDIEEntry(Element, Entry);
1248 if (CTy.isAppleBlockExtension())
1249 addFlag(Buffer, dwarf::DW_AT_APPLE_block);
1251 DICompositeType ContainingType(resolve(CTy.getContainingType()));
1253 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
1254 *getOrCreateTypeDIE(ContainingType));
1256 if (CTy.isObjcClassComplete())
1257 addFlag(Buffer, dwarf::DW_AT_APPLE_objc_complete_type);
1259 // Add template parameters to a class, structure or union types.
1260 // FIXME: The support isn't in the metadata for this yet.
1261 if (Tag == dwarf::DW_TAG_class_type ||
1262 Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
1263 addTemplateParams(Buffer, CTy.getTemplateParams());
1271 // Add name if not anonymous or intermediate type.
1273 addString(Buffer, dwarf::DW_AT_name, Name);
1275 if (Tag == dwarf::DW_TAG_enumeration_type ||
1276 Tag == dwarf::DW_TAG_class_type || Tag == dwarf::DW_TAG_structure_type ||
1277 Tag == dwarf::DW_TAG_union_type) {
1278 // Add size if non-zero (derived types might be zero-sized.)
1279 // TODO: Do we care about size for enum forward declarations?
1281 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
1282 else if (!CTy.isForwardDecl())
1283 // Add zero size if it is not a forward declaration.
1284 addUInt(Buffer, dwarf::DW_AT_byte_size, None, 0);
1286 // If we're a forward decl, say so.
1287 if (CTy.isForwardDecl())
1288 addFlag(Buffer, dwarf::DW_AT_declaration);
1290 // Add source line info if available.
1291 if (!CTy.isForwardDecl())
1292 addSourceLine(Buffer, CTy);
1294 // No harm in adding the runtime language to the declaration.
1295 unsigned RLang = CTy.getRunTimeLang();
1297 addUInt(Buffer, dwarf::DW_AT_APPLE_runtime_class, dwarf::DW_FORM_data1,
1302 /// constructTemplateTypeParameterDIE - Construct new DIE for the given
1303 /// DITemplateTypeParameter.
1304 void DwarfUnit::constructTemplateTypeParameterDIE(DIE &Buffer,
1305 DITemplateTypeParameter TP) {
1307 createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
1308 // Add the type if it exists, it could be void and therefore no type.
1310 addType(ParamDIE, resolve(TP.getType()));
1311 if (!TP.getName().empty())
1312 addString(ParamDIE, dwarf::DW_AT_name, TP.getName());
1315 /// constructTemplateValueParameterDIE - Construct new DIE for the given
1316 /// DITemplateValueParameter.
1318 DwarfUnit::constructTemplateValueParameterDIE(DIE &Buffer,
1319 DITemplateValueParameter VP) {
1320 DIE &ParamDIE = createAndAddDIE(VP.getTag(), Buffer);
1322 // Add the type if there is one, template template and template parameter
1323 // packs will not have a type.
1324 if (VP.getTag() == dwarf::DW_TAG_template_value_parameter)
1325 addType(ParamDIE, resolve(VP.getType()));
1326 if (!VP.getName().empty())
1327 addString(ParamDIE, dwarf::DW_AT_name, VP.getName());
1328 if (Value *Val = VP.getValue()) {
1329 if (ConstantInt *CI = dyn_cast<ConstantInt>(Val))
1330 addConstantValue(ParamDIE, CI, resolve(VP.getType()));
1331 else if (GlobalValue *GV = dyn_cast<GlobalValue>(Val)) {
1332 // For declaration non-type template parameters (such as global values and
1334 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
1335 addOpAddress(*Loc, Asm->getSymbol(GV));
1336 // Emit DW_OP_stack_value to use the address as the immediate value of the
1337 // parameter, rather than a pointer to it.
1338 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_stack_value);
1339 addBlock(ParamDIE, dwarf::DW_AT_location, Loc);
1340 } else if (VP.getTag() == dwarf::DW_TAG_GNU_template_template_param) {
1341 assert(isa<MDString>(Val));
1342 addString(ParamDIE, dwarf::DW_AT_GNU_template_name,
1343 cast<MDString>(Val)->getString());
1344 } else if (VP.getTag() == dwarf::DW_TAG_GNU_template_parameter_pack) {
1345 assert(isa<MDNode>(Val));
1346 DIArray A(cast<MDNode>(Val));
1347 addTemplateParams(ParamDIE, A);
1352 /// getOrCreateNameSpace - Create a DIE for DINameSpace.
1353 DIE *DwarfUnit::getOrCreateNameSpace(DINameSpace NS) {
1354 // Construct the context before querying for the existence of the DIE in case
1355 // such construction creates the DIE.
1356 DIE *ContextDIE = getOrCreateContextDIE(NS.getContext());
1358 if (DIE *NDie = getDIE(NS))
1360 DIE &NDie = createAndAddDIE(dwarf::DW_TAG_namespace, *ContextDIE, NS);
1362 if (!NS.getName().empty()) {
1363 addString(NDie, dwarf::DW_AT_name, NS.getName());
1364 DD->addAccelNamespace(NS.getName(), NDie);
1365 addGlobalName(NS.getName(), NDie, NS.getContext());
1367 DD->addAccelNamespace("(anonymous namespace)", NDie);
1368 addSourceLine(NDie, NS);
1372 /// getOrCreateSubprogramDIE - Create new DIE using SP.
1373 DIE *DwarfUnit::getOrCreateSubprogramDIE(DISubprogram SP) {
1374 // Construct the context before querying for the existence of the DIE in case
1375 // such construction creates the DIE (as is the case for member function
1377 DIScope Context = resolve(SP.getContext());
1378 DIE *ContextDIE = getOrCreateContextDIE(Context);
1380 if (DIE *SPDie = getDIE(SP))
1383 DIE *DeclDie = nullptr;
1384 StringRef DeclLinkageName;
1385 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
1386 // Add subprogram definitions to the CU die directly.
1387 ContextDIE = &getUnitDie();
1388 DeclDie = getOrCreateSubprogramDIE(SPDecl);
1389 DeclLinkageName = SPDecl.getLinkageName();
1392 // DW_TAG_inlined_subroutine may refer to this DIE.
1393 DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
1396 // Add function template parameters.
1397 addTemplateParams(SPDie, SP.getTemplateParams());
1399 // Add the linkage name if we have one and it isn't in the Decl.
1400 StringRef LinkageName = SP.getLinkageName();
1401 assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
1402 LinkageName == DeclLinkageName) &&
1403 "decl has a linkage name and it is different");
1404 if (!LinkageName.empty() && DeclLinkageName.empty())
1405 addString(SPDie, dwarf::DW_AT_MIPS_linkage_name,
1406 GlobalValue::getRealLinkageName(LinkageName));
1409 // Refer to the function declaration where all the other attributes will be
1411 addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
1415 // Constructors and operators for anonymous aggregates do not have names.
1416 if (!SP.getName().empty())
1417 addString(SPDie, dwarf::DW_AT_name, SP.getName());
1419 addSourceLine(SPDie, SP);
1421 // Add the prototype if we have a prototype and we have a C like
1423 uint16_t Language = getLanguage();
1424 if (SP.isPrototyped() &&
1425 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1426 Language == dwarf::DW_LANG_ObjC))
1427 addFlag(SPDie, dwarf::DW_AT_prototyped);
1429 DICompositeType SPTy = SP.getType();
1430 assert(SPTy.getTag() == dwarf::DW_TAG_subroutine_type &&
1431 "the type of a subprogram should be a subroutine");
1433 DIArray Args = SPTy.getTypeArray();
1434 // Add a return type. If this is a type like a C/C++ void type we don't add a
1436 if (Args.getElement(0))
1437 addType(SPDie, DIType(Args.getElement(0)));
1439 unsigned VK = SP.getVirtuality();
1441 addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1, VK);
1442 DIELoc *Block = getDIELoc();
1443 addUInt(*Block, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1444 addUInt(*Block, dwarf::DW_FORM_udata, SP.getVirtualIndex());
1445 addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
1446 ContainingTypeMap.insert(
1447 std::make_pair(&SPDie, resolve(SP.getContainingType())));
1450 if (!SP.isDefinition()) {
1451 addFlag(SPDie, dwarf::DW_AT_declaration);
1453 // Add arguments. Do not add arguments for subprogram definition. They will
1454 // be handled while processing variables.
1455 constructSubprogramArguments(SPDie, Args);
1458 if (SP.isArtificial())
1459 addFlag(SPDie, dwarf::DW_AT_artificial);
1461 if (!SP.isLocalToUnit())
1462 addFlag(SPDie, dwarf::DW_AT_external);
1464 if (SP.isOptimized())
1465 addFlag(SPDie, dwarf::DW_AT_APPLE_optimized);
1467 if (unsigned isa = Asm->getISAEncoding()) {
1468 addUInt(SPDie, dwarf::DW_AT_APPLE_isa, dwarf::DW_FORM_flag, isa);
1471 if (SP.isLValueReference())
1472 addFlag(SPDie, dwarf::DW_AT_reference);
1474 if (SP.isRValueReference())
1475 addFlag(SPDie, dwarf::DW_AT_rvalue_reference);
1477 if (SP.isProtected())
1478 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1479 dwarf::DW_ACCESS_protected);
1480 else if (SP.isPrivate())
1481 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1482 dwarf::DW_ACCESS_private);
1484 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1485 dwarf::DW_ACCESS_public);
1487 if (SP.isExplicit())
1488 addFlag(SPDie, dwarf::DW_AT_explicit);
1493 // Return const expression if value is a GEP to access merged global
1495 // i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
1496 static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
1497 const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
1498 if (!CE || CE->getNumOperands() != 3 ||
1499 CE->getOpcode() != Instruction::GetElementPtr)
1502 // First operand points to a global struct.
1503 Value *Ptr = CE->getOperand(0);
1504 if (!isa<GlobalValue>(Ptr) ||
1505 !isa<StructType>(cast<PointerType>(Ptr->getType())->getElementType()))
1508 // Second operand is zero.
1509 const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
1510 if (!CI || !CI->isZero())
1513 // Third operand is offset.
1514 if (!isa<ConstantInt>(CE->getOperand(2)))
1520 /// createGlobalVariableDIE - create global variable DIE.
1521 void DwarfCompileUnit::createGlobalVariableDIE(DIGlobalVariable GV) {
1522 // Check for pre-existence.
1526 assert(GV.isGlobalVariable());
1528 DIScope GVContext = GV.getContext();
1529 DIType GTy = DD->resolve(GV.getType());
1531 // If this is a static data member definition, some attributes belong
1532 // to the declaration DIE.
1533 DIE *VariableDIE = nullptr;
1534 bool IsStaticMember = false;
1535 DIDerivedType SDMDecl = GV.getStaticDataMemberDeclaration();
1536 if (SDMDecl.Verify()) {
1537 assert(SDMDecl.isStaticMember() && "Expected static member decl");
1538 // We need the declaration DIE that is in the static member's class.
1539 VariableDIE = getOrCreateStaticMemberDIE(SDMDecl);
1540 IsStaticMember = true;
1543 // If this is not a static data member definition, create the variable
1544 // DIE and add the initial set of attributes to it.
1546 // Construct the context before querying for the existence of the DIE in
1547 // case such construction creates the DIE.
1548 DIE *ContextDIE = getOrCreateContextDIE(GVContext);
1551 VariableDIE = &createAndAddDIE(GV.getTag(), *ContextDIE, GV);
1553 // Add name and type.
1554 addString(*VariableDIE, dwarf::DW_AT_name, GV.getDisplayName());
1555 addType(*VariableDIE, GTy);
1557 // Add scoping info.
1558 if (!GV.isLocalToUnit())
1559 addFlag(*VariableDIE, dwarf::DW_AT_external);
1561 // Add line number info.
1562 addSourceLine(*VariableDIE, GV);
1566 bool addToAccelTable = false;
1567 DIE *VariableSpecDIE = nullptr;
1568 bool isGlobalVariable = GV.getGlobal() != nullptr;
1569 if (isGlobalVariable) {
1570 addToAccelTable = true;
1571 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
1572 const MCSymbol *Sym = Asm->getSymbol(GV.getGlobal());
1573 if (GV.getGlobal()->isThreadLocal()) {
1574 // FIXME: Make this work with -gsplit-dwarf.
1575 unsigned PointerSize = Asm->getDataLayout().getPointerSize();
1576 assert((PointerSize == 4 || PointerSize == 8) &&
1577 "Add support for other sizes if necessary");
1578 // Based on GCC's support for TLS:
1579 if (!DD->useSplitDwarf()) {
1580 // 1) Start with a constNu of the appropriate pointer size
1581 addUInt(*Loc, dwarf::DW_FORM_data1,
1582 PointerSize == 4 ? dwarf::DW_OP_const4u : dwarf::DW_OP_const8u);
1583 // 2) containing the (relocated) offset of the TLS variable
1584 // within the module's TLS block.
1585 addExpr(*Loc, dwarf::DW_FORM_udata,
1586 Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
1588 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
1589 addUInt(*Loc, dwarf::DW_FORM_udata,
1590 DD->getAddressPool().getIndex(Sym, /* TLS */ true));
1592 // 3) followed by a custom OP to make the debugger do a TLS lookup.
1593 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_push_tls_address);
1595 DD->addArangeLabel(SymbolCU(this, Sym));
1596 addOpAddress(*Loc, Sym);
1598 // Do not create specification DIE if context is either compile unit
1600 if (GVContext && GV.isDefinition() && !GVContext.isCompileUnit() &&
1601 !GVContext.isFile() && !DD->isSubprogramContext(GVContext)) {
1602 // Create specification DIE.
1603 VariableSpecDIE = &createAndAddDIE(dwarf::DW_TAG_variable, UnitDie);
1604 addDIEEntry(*VariableSpecDIE, dwarf::DW_AT_specification, *VariableDIE);
1605 addBlock(*VariableSpecDIE, dwarf::DW_AT_location, Loc);
1606 // A static member's declaration is already flagged as such.
1607 if (!SDMDecl.Verify())
1608 addFlag(*VariableDIE, dwarf::DW_AT_declaration);
1610 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
1612 // Add the linkage name.
1613 StringRef LinkageName = GV.getLinkageName();
1614 if (!LinkageName.empty())
1615 // From DWARF4: DIEs to which DW_AT_linkage_name may apply include:
1616 // TAG_common_block, TAG_constant, TAG_entry_point, TAG_subprogram and
1618 addString(IsStaticMember && VariableSpecDIE ? *VariableSpecDIE
1620 DD->getDwarfVersion() >= 4 ? dwarf::DW_AT_linkage_name
1621 : dwarf::DW_AT_MIPS_linkage_name,
1622 GlobalValue::getRealLinkageName(LinkageName));
1623 } else if (const ConstantInt *CI =
1624 dyn_cast_or_null<ConstantInt>(GV.getConstant())) {
1625 // AT_const_value was added when the static member was created. To avoid
1626 // emitting AT_const_value multiple times, we only add AT_const_value when
1627 // it is not a static member.
1628 if (!IsStaticMember)
1629 addConstantValue(*VariableDIE, CI, GTy);
1630 } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV->getOperand(11))) {
1631 addToAccelTable = true;
1632 // GV is a merged global.
1633 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
1634 Value *Ptr = CE->getOperand(0);
1635 MCSymbol *Sym = Asm->getSymbol(cast<GlobalValue>(Ptr));
1636 DD->addArangeLabel(SymbolCU(this, Sym));
1637 addOpAddress(*Loc, Sym);
1638 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1639 SmallVector<Value *, 3> Idx(CE->op_begin() + 1, CE->op_end());
1640 addUInt(*Loc, dwarf::DW_FORM_udata,
1641 Asm->getDataLayout().getIndexedOffset(Ptr->getType(), Idx));
1642 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
1643 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
1646 if (addToAccelTable) {
1647 DIE &AddrDIE = VariableSpecDIE ? *VariableSpecDIE : *VariableDIE;
1648 DD->addAccelName(GV.getName(), AddrDIE);
1650 // If the linkage name is different than the name, go ahead and output
1651 // that as well into the name table.
1652 if (GV.getLinkageName() != "" && GV.getName() != GV.getLinkageName())
1653 DD->addAccelName(GV.getLinkageName(), AddrDIE);
1656 if (!GV.isLocalToUnit())
1657 addGlobalName(GV.getName(),
1658 VariableSpecDIE ? *VariableSpecDIE : *VariableDIE,
1662 /// constructSubrangeDIE - Construct subrange DIE from DISubrange.
1663 void DwarfUnit::constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy) {
1664 DIE &DW_Subrange = createAndAddDIE(dwarf::DW_TAG_subrange_type, Buffer);
1665 addDIEEntry(DW_Subrange, dwarf::DW_AT_type, *IndexTy);
1667 // The LowerBound value defines the lower bounds which is typically zero for
1668 // C/C++. The Count value is the number of elements. Values are 64 bit. If
1669 // Count == -1 then the array is unbounded and we do not emit
1670 // DW_AT_lower_bound and DW_AT_upper_bound attributes. If LowerBound == 0 and
1671 // Count == 0, then the array has zero elements in which case we do not emit
1673 int64_t LowerBound = SR.getLo();
1674 int64_t DefaultLowerBound = getDefaultLowerBound();
1675 int64_t Count = SR.getCount();
1677 if (DefaultLowerBound == -1 || LowerBound != DefaultLowerBound)
1678 addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, None, LowerBound);
1680 if (Count != -1 && Count != 0)
1681 // FIXME: An unbounded array should reference the expression that defines
1683 addUInt(DW_Subrange, dwarf::DW_AT_upper_bound, None,
1684 LowerBound + Count - 1);
1687 /// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
1688 void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, DICompositeType CTy) {
1690 addFlag(Buffer, dwarf::DW_AT_GNU_vector);
1692 // Emit the element type.
1693 addType(Buffer, resolve(CTy.getTypeDerivedFrom()));
1695 // Get an anonymous type for index type.
1696 // FIXME: This type should be passed down from the front end
1697 // as different languages may have different sizes for indexes.
1698 DIE *IdxTy = getIndexTyDie();
1700 // Construct an integer type to use for indexes.
1701 IdxTy = &createAndAddDIE(dwarf::DW_TAG_base_type, UnitDie);
1702 addString(*IdxTy, dwarf::DW_AT_name, "sizetype");
1703 addUInt(*IdxTy, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
1704 addUInt(*IdxTy, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
1705 dwarf::DW_ATE_unsigned);
1706 setIndexTyDie(IdxTy);
1709 // Add subranges to array type.
1710 DIArray Elements = CTy.getTypeArray();
1711 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1712 DIDescriptor Element = Elements.getElement(i);
1713 if (Element.getTag() == dwarf::DW_TAG_subrange_type)
1714 constructSubrangeDIE(Buffer, DISubrange(Element), IdxTy);
1718 /// constructEnumTypeDIE - Construct an enum type DIE from DICompositeType.
1719 void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, DICompositeType CTy) {
1720 DIArray Elements = CTy.getTypeArray();
1722 // Add enumerators to enumeration type.
1723 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1724 DIEnumerator Enum(Elements.getElement(i));
1725 if (Enum.isEnumerator()) {
1726 DIE &Enumerator = createAndAddDIE(dwarf::DW_TAG_enumerator, Buffer);
1727 StringRef Name = Enum.getName();
1728 addString(Enumerator, dwarf::DW_AT_name, Name);
1729 int64_t Value = Enum.getEnumValue();
1730 addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
1734 DIType DTy = resolve(CTy.getTypeDerivedFrom());
1736 addType(Buffer, DTy);
1737 addFlag(Buffer, dwarf::DW_AT_enum_class);
1741 /// constructContainingTypeDIEs - Construct DIEs for types that contain
1743 void DwarfUnit::constructContainingTypeDIEs() {
1744 for (DenseMap<DIE *, const MDNode *>::iterator CI = ContainingTypeMap.begin(),
1745 CE = ContainingTypeMap.end();
1747 DIE &SPDie = *CI->first;
1748 DIDescriptor D(CI->second);
1751 DIE *NDie = getDIE(D);
1754 addDIEEntry(SPDie, dwarf::DW_AT_containing_type, *NDie);
1758 /// constructVariableDIE - Construct a DIE for the given DbgVariable.
1759 std::unique_ptr<DIE> DwarfUnit::constructVariableDIE(DbgVariable &DV,
1760 AbstractOrInlined AbsIn) {
1761 auto D = constructVariableDIEImpl(DV, AbsIn);
1766 std::unique_ptr<DIE>
1767 DwarfUnit::constructVariableDIEImpl(const DbgVariable &DV,
1768 AbstractOrInlined AbsIn) {
1769 StringRef Name = DV.getName();
1771 // Define variable debug information entry.
1772 auto VariableDie = make_unique<DIE>(DV.getTag());
1773 DbgVariable *AbsVar = DV.getAbstractVariable();
1774 DIE *AbsDIE = AbsVar ? AbsVar->getDIE() : nullptr;
1776 addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin, *AbsDIE);
1779 addString(*VariableDie, dwarf::DW_AT_name, Name);
1780 addSourceLine(*VariableDie, DV.getVariable());
1781 addType(*VariableDie, DV.getType());
1784 if (AbsIn != AOI_Inlined && DV.isArtificial())
1785 addFlag(*VariableDie, dwarf::DW_AT_artificial);
1787 if (AbsIn == AOI_Abstract)
1790 // Add variable address.
1792 unsigned Offset = DV.getDotDebugLocOffset();
1793 if (Offset != ~0U) {
1794 addLocationList(*VariableDie, dwarf::DW_AT_location, Offset);
1798 // Check if variable is described by a DBG_VALUE instruction.
1799 if (const MachineInstr *DVInsn = DV.getMInsn()) {
1800 assert(DVInsn->getNumOperands() == 3);
1801 if (DVInsn->getOperand(0).isReg()) {
1802 const MachineOperand RegOp = DVInsn->getOperand(0);
1803 // If the second operand is an immediate, this is an indirect value.
1804 if (DVInsn->getOperand(1).isImm()) {
1805 MachineLocation Location(RegOp.getReg(),
1806 DVInsn->getOperand(1).getImm());
1807 addVariableAddress(DV, *VariableDie, Location);
1808 } else if (RegOp.getReg())
1809 addVariableAddress(DV, *VariableDie, MachineLocation(RegOp.getReg()));
1810 } else if (DVInsn->getOperand(0).isImm())
1811 addConstantValue(*VariableDie, DVInsn->getOperand(0), DV.getType());
1812 else if (DVInsn->getOperand(0).isFPImm())
1813 addConstantFPValue(*VariableDie, DVInsn->getOperand(0));
1814 else if (DVInsn->getOperand(0).isCImm())
1815 addConstantValue(*VariableDie, DVInsn->getOperand(0).getCImm(),
1821 // .. else use frame index.
1822 int FI = DV.getFrameIndex();
1824 unsigned FrameReg = 0;
1825 const TargetFrameLowering *TFI = Asm->TM.getFrameLowering();
1826 int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg);
1827 MachineLocation Location(FrameReg, Offset);
1828 addVariableAddress(DV, *VariableDie, Location);
1834 /// constructMemberDIE - Construct member DIE from DIDerivedType.
1835 void DwarfUnit::constructMemberDIE(DIE &Buffer, DIDerivedType DT) {
1836 DIE &MemberDie = createAndAddDIE(DT.getTag(), Buffer);
1837 StringRef Name = DT.getName();
1839 addString(MemberDie, dwarf::DW_AT_name, Name);
1841 addType(MemberDie, resolve(DT.getTypeDerivedFrom()));
1843 addSourceLine(MemberDie, DT);
1845 if (DT.getTag() == dwarf::DW_TAG_inheritance && DT.isVirtual()) {
1847 // For C++, virtual base classes are not at fixed offset. Use following
1848 // expression to extract appropriate offset from vtable.
1849 // BaseAddr = ObAddr + *((*ObAddr) - Offset)
1851 DIELoc *VBaseLocationDie = new (DIEValueAllocator) DIELoc();
1852 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
1853 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1854 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1855 addUInt(*VBaseLocationDie, dwarf::DW_FORM_udata, DT.getOffsetInBits());
1856 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
1857 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1858 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
1860 addBlock(MemberDie, dwarf::DW_AT_data_member_location, VBaseLocationDie);
1862 uint64_t Size = DT.getSizeInBits();
1863 uint64_t FieldSize = getBaseTypeSize(DD, DT);
1864 uint64_t OffsetInBytes;
1866 if (Size != FieldSize) {
1867 // Handle bitfield, assume bytes are 8 bits.
1868 addUInt(MemberDie, dwarf::DW_AT_byte_size, None, FieldSize/8);
1869 addUInt(MemberDie, dwarf::DW_AT_bit_size, None, Size);
1871 uint64_t Offset = DT.getOffsetInBits();
1872 uint64_t AlignMask = ~(DT.getAlignInBits() - 1);
1873 uint64_t HiMark = (Offset + FieldSize) & AlignMask;
1874 uint64_t FieldOffset = (HiMark - FieldSize);
1875 Offset -= FieldOffset;
1877 // Maybe we need to work from the other end.
1878 if (Asm->getDataLayout().isLittleEndian())
1879 Offset = FieldSize - (Offset + Size);
1880 addUInt(MemberDie, dwarf::DW_AT_bit_offset, None, Offset);
1882 // Here DW_AT_data_member_location points to the anonymous
1883 // field that includes this bit field.
1884 OffsetInBytes = FieldOffset >> 3;
1886 // This is not a bitfield.
1887 OffsetInBytes = DT.getOffsetInBits() >> 3;
1889 if (DD->getDwarfVersion() <= 2) {
1890 DIELoc *MemLocationDie = new (DIEValueAllocator) DIELoc();
1891 addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
1892 addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes);
1893 addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie);
1895 addUInt(MemberDie, dwarf::DW_AT_data_member_location, None,
1899 if (DT.isProtected())
1900 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1901 dwarf::DW_ACCESS_protected);
1902 else if (DT.isPrivate())
1903 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1904 dwarf::DW_ACCESS_private);
1905 // Otherwise C++ member and base classes are considered public.
1907 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1908 dwarf::DW_ACCESS_public);
1910 addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1,
1911 dwarf::DW_VIRTUALITY_virtual);
1913 // Objective-C properties.
1914 if (MDNode *PNode = DT.getObjCProperty())
1915 if (DIEEntry *PropertyDie = getDIEEntry(PNode))
1916 MemberDie.addValue(dwarf::DW_AT_APPLE_property, dwarf::DW_FORM_ref4,
1919 if (DT.isArtificial())
1920 addFlag(MemberDie, dwarf::DW_AT_artificial);
1923 /// getOrCreateStaticMemberDIE - Create new DIE for C++ static member.
1924 DIE *DwarfUnit::getOrCreateStaticMemberDIE(DIDerivedType DT) {
1928 // Construct the context before querying for the existence of the DIE in case
1929 // such construction creates the DIE.
1930 DIE *ContextDIE = getOrCreateContextDIE(resolve(DT.getContext()));
1931 assert(dwarf::isType(ContextDIE->getTag()) &&
1932 "Static member should belong to a type.");
1934 if (DIE *StaticMemberDIE = getDIE(DT))
1935 return StaticMemberDIE;
1937 DIE &StaticMemberDIE = createAndAddDIE(DT.getTag(), *ContextDIE, DT);
1939 DIType Ty = resolve(DT.getTypeDerivedFrom());
1941 addString(StaticMemberDIE, dwarf::DW_AT_name, DT.getName());
1942 addType(StaticMemberDIE, Ty);
1943 addSourceLine(StaticMemberDIE, DT);
1944 addFlag(StaticMemberDIE, dwarf::DW_AT_external);
1945 addFlag(StaticMemberDIE, dwarf::DW_AT_declaration);
1947 // FIXME: We could omit private if the parent is a class_type, and
1948 // public if the parent is something else.
1949 if (DT.isProtected())
1950 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1951 dwarf::DW_ACCESS_protected);
1952 else if (DT.isPrivate())
1953 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1954 dwarf::DW_ACCESS_private);
1956 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1957 dwarf::DW_ACCESS_public);
1959 if (const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(DT.getConstant()))
1960 addConstantValue(StaticMemberDIE, CI, Ty);
1961 if (const ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(DT.getConstant()))
1962 addConstantFPValue(StaticMemberDIE, CFP);
1964 return &StaticMemberDIE;
1967 void DwarfUnit::emitHeader(const MCSymbol *ASectionSym) const {
1968 Asm->OutStreamer.AddComment("DWARF version number");
1969 Asm->EmitInt16(DD->getDwarfVersion());
1970 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section");
1971 // We share one abbreviations table across all units so it's always at the
1972 // start of the section. Use a relocatable offset where needed to ensure
1973 // linking doesn't invalidate that offset.
1975 Asm->EmitSectionOffset(ASectionSym, ASectionSym);
1977 // Use a constant value when no symbol is provided.
1979 Asm->OutStreamer.AddComment("Address Size (in bytes)");
1980 Asm->EmitInt8(Asm->getDataLayout().getPointerSize());
1983 void DwarfUnit::addRange(RangeSpan Range) {
1984 // Only add a range for this unit if we're emitting full debug.
1985 if (getCUNode().getEmissionKind() == DIBuilder::FullDebug) {
1986 // If we have no current ranges just add the range and return, otherwise,
1987 // check the current section and CU against the previous section and CU we
1988 // emitted into and the subprogram was contained within. If these are the
1989 // same then extend our current range, otherwise add this as a new range.
1990 if (CURanges.size() == 0 ||
1991 this != DD->getPrevCU() ||
1992 Asm->getCurrentSection() != DD->getPrevSection()) {
1993 CURanges.push_back(Range);
1997 assert(&(CURanges.back().getEnd()->getSection()) ==
1998 &(Range.getEnd()->getSection()) &&
1999 "We can only append to a range in the same section!");
2000 CURanges.back().setEnd(Range.getEnd());
2004 void DwarfCompileUnit::initStmtList(MCSymbol *DwarfLineSectionSym) {
2005 // Define start line table label for each Compile Unit.
2006 MCSymbol *LineTableStartSym =
2007 Asm->OutStreamer.getDwarfLineTableSymbol(getUniqueID());
2009 stmtListIndex = UnitDie.getValues().size();
2011 // DW_AT_stmt_list is a offset of line number information for this
2012 // compile unit in debug_line section. For split dwarf this is
2013 // left in the skeleton CU and so not included.
2014 // The line table entries are not always emitted in assembly, so it
2015 // is not okay to use line_table_start here.
2016 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
2017 addSectionLabel(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym);
2019 addSectionDelta(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym,
2020 DwarfLineSectionSym);
2023 void DwarfCompileUnit::applyStmtList(DIE &D) {
2024 D.addValue(dwarf::DW_AT_stmt_list,
2025 UnitDie.getAbbrev().getData()[stmtListIndex].getForm(),
2026 UnitDie.getValues()[stmtListIndex]);
2029 void DwarfTypeUnit::emitHeader(const MCSymbol *ASectionSym) const {
2030 DwarfUnit::emitHeader(ASectionSym);
2031 Asm->OutStreamer.AddComment("Type Signature");
2032 Asm->OutStreamer.EmitIntValue(TypeSignature, sizeof(TypeSignature));
2033 Asm->OutStreamer.AddComment("Type DIE Offset");
2034 // In a skeleton type unit there is no type DIE so emit a zero offset.
2035 Asm->OutStreamer.EmitIntValue(Ty ? Ty->getOffset() : 0,
2036 sizeof(Ty->getOffset()));
2039 void DwarfTypeUnit::initSection(const MCSection *Section) {
2040 assert(!this->Section);
2041 this->Section = Section;
2042 // Since each type unit is contained in its own COMDAT section, the begin
2043 // label and the section label are the same. Using the begin label emission in
2044 // DwarfDebug to emit the section label as well is slightly subtle/sneaky, but
2045 // the only other alternative of lazily constructing start-of-section labels
2046 // and storing a mapping in DwarfDebug (or AsmPrinter).
2047 this->SectionSym = this->LabelBegin =
2048 Asm->GetTempSymbol(Section->getLabelBeginName(), getUniqueID());
2050 Asm->GetTempSymbol(Section->getLabelEndName(), getUniqueID());