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/CodeGen/MachineFunction.h"
21 #include "llvm/IR/Constants.h"
22 #include "llvm/IR/DIBuilder.h"
23 #include "llvm/IR/DataLayout.h"
24 #include "llvm/IR/GlobalVariable.h"
25 #include "llvm/IR/Instructions.h"
26 #include "llvm/IR/Mangler.h"
27 #include "llvm/MC/MCAsmInfo.h"
28 #include "llvm/MC/MCContext.h"
29 #include "llvm/MC/MCSection.h"
30 #include "llvm/MC/MCStreamer.h"
31 #include "llvm/Support/CommandLine.h"
32 #include "llvm/Target/TargetFrameLowering.h"
33 #include "llvm/Target/TargetLoweringObjectFile.h"
34 #include "llvm/Target/TargetMachine.h"
35 #include "llvm/Target/TargetRegisterInfo.h"
36 #include "llvm/Target/TargetSubtargetInfo.h"
40 #define DEBUG_TYPE "dwarfdebug"
43 GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
44 cl::desc("Generate DWARF4 type units."),
47 DIEDwarfExpression::DIEDwarfExpression(const AsmPrinter &AP, DwarfUnit &DU,
49 : DwarfExpression(*AP.MF->getSubtarget().getRegisterInfo(),
50 AP.getDwarfDebug()->getDwarfVersion()),
51 AP(AP), DU(DU), DIE(DIE) {}
53 void DIEDwarfExpression::EmitOp(uint8_t Op, const char* Comment) {
54 DU.addUInt(DIE, dwarf::DW_FORM_data1, Op);
56 void DIEDwarfExpression::EmitSigned(int64_t Value) {
57 DU.addSInt(DIE, dwarf::DW_FORM_sdata, Value);
59 void DIEDwarfExpression::EmitUnsigned(uint64_t Value) {
60 DU.addUInt(DIE, dwarf::DW_FORM_udata, Value);
62 bool DIEDwarfExpression::isFrameRegister(unsigned MachineReg) {
63 return MachineReg == TRI.getFrameRegister(*AP.MF);
67 /// Unit - Unit constructor.
68 DwarfUnit::DwarfUnit(unsigned UID, dwarf::Tag UnitTag, DICompileUnit Node,
69 AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU)
70 : UniqueID(UID), CUNode(Node), UnitDie(UnitTag), DebugInfoOffset(0), Asm(A),
71 DD(DW), DU(DWU), IndexTyDie(nullptr), Section(nullptr) {
72 assert(UnitTag == dwarf::DW_TAG_compile_unit ||
73 UnitTag == dwarf::DW_TAG_type_unit);
74 DIEIntegerOne = new (DIEValueAllocator) DIEInteger(1);
77 DwarfTypeUnit::DwarfTypeUnit(unsigned UID, DwarfCompileUnit &CU, AsmPrinter *A,
78 DwarfDebug *DW, DwarfFile *DWU,
79 MCDwarfDwoLineTable *SplitLineTable)
80 : DwarfUnit(UID, dwarf::DW_TAG_type_unit, CU.getCUNode(), A, DW, DWU),
81 CU(CU), SplitLineTable(SplitLineTable) {
83 addSectionOffset(UnitDie, dwarf::DW_AT_stmt_list, 0);
86 /// ~Unit - Destructor for compile unit.
87 DwarfUnit::~DwarfUnit() {
88 for (unsigned j = 0, M = DIEBlocks.size(); j < M; ++j)
89 DIEBlocks[j]->~DIEBlock();
90 for (unsigned j = 0, M = DIELocs.size(); j < M; ++j)
91 DIELocs[j]->~DIELoc();
94 /// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
95 /// information entry.
96 DIEEntry *DwarfUnit::createDIEEntry(DIE &Entry) {
97 DIEEntry *Value = new (DIEValueAllocator) DIEEntry(Entry);
101 /// getDefaultLowerBound - Return the default lower bound for an array. If the
102 /// DWARF version doesn't handle the language, return -1.
103 int64_t DwarfUnit::getDefaultLowerBound() const {
104 switch (getLanguage()) {
108 case dwarf::DW_LANG_C89:
109 case dwarf::DW_LANG_C99:
110 case dwarf::DW_LANG_C:
111 case dwarf::DW_LANG_C_plus_plus:
112 case dwarf::DW_LANG_ObjC:
113 case dwarf::DW_LANG_ObjC_plus_plus:
116 case dwarf::DW_LANG_Fortran77:
117 case dwarf::DW_LANG_Fortran90:
118 case dwarf::DW_LANG_Fortran95:
121 // The languages below have valid values only if the DWARF version >= 4.
122 case dwarf::DW_LANG_Java:
123 case dwarf::DW_LANG_Python:
124 case dwarf::DW_LANG_UPC:
125 case dwarf::DW_LANG_D:
126 if (dwarf::DWARF_VERSION >= 4)
130 case dwarf::DW_LANG_Ada83:
131 case dwarf::DW_LANG_Ada95:
132 case dwarf::DW_LANG_Cobol74:
133 case dwarf::DW_LANG_Cobol85:
134 case dwarf::DW_LANG_Modula2:
135 case dwarf::DW_LANG_Pascal83:
136 case dwarf::DW_LANG_PLI:
137 if (dwarf::DWARF_VERSION >= 4)
141 // The languages below have valid values only if the DWARF version >= 5.
142 case dwarf::DW_LANG_OpenCL:
143 case dwarf::DW_LANG_Go:
144 case dwarf::DW_LANG_Haskell:
145 case dwarf::DW_LANG_C_plus_plus_03:
146 case dwarf::DW_LANG_C_plus_plus_11:
147 case dwarf::DW_LANG_OCaml:
148 case dwarf::DW_LANG_Rust:
149 case dwarf::DW_LANG_C11:
150 case dwarf::DW_LANG_Swift:
151 case dwarf::DW_LANG_Dylan:
152 case dwarf::DW_LANG_C_plus_plus_14:
153 if (dwarf::DWARF_VERSION >= 5)
157 case dwarf::DW_LANG_Modula3:
158 case dwarf::DW_LANG_Julia:
159 case dwarf::DW_LANG_Fortran03:
160 case dwarf::DW_LANG_Fortran08:
161 if (dwarf::DWARF_VERSION >= 5)
169 /// Check whether the DIE for this MDNode can be shared across CUs.
170 static bool isShareableAcrossCUs(const DebugNode *D) {
171 // When the MDNode can be part of the type system, the DIE can be shared
173 // Combining type units and cross-CU DIE sharing is lower value (since
174 // cross-CU DIE sharing is used in LTO and removes type redundancy at that
175 // level already) but may be implementable for some value in projects
176 // building multiple independent libraries with LTO and then linking those
178 return (isa<MDType>(D) ||
179 (isa<MDSubprogram>(D) && !cast<MDSubprogram>(D)->isDefinition())) &&
180 !GenerateDwarfTypeUnits;
183 /// getDIE - Returns the debug information entry map slot for the
184 /// specified debug variable. We delegate the request to DwarfDebug
185 /// when the DIE for this MDNode can be shared across CUs. The mappings
186 /// will be kept in DwarfDebug for shareable DIEs.
187 DIE *DwarfUnit::getDIE(const DebugNode *D) const {
188 if (isShareableAcrossCUs(D))
189 return DU->getDIE(D);
190 return MDNodeToDieMap.lookup(D);
193 /// insertDIE - Insert DIE into the map. We delegate the request to DwarfDebug
194 /// when the DIE for this MDNode can be shared across CUs. The mappings
195 /// will be kept in DwarfDebug for shareable DIEs.
196 void DwarfUnit::insertDIE(const DebugNode *Desc, DIE *D) {
197 if (isShareableAcrossCUs(Desc)) {
198 DU->insertDIE(Desc, D);
201 MDNodeToDieMap.insert(std::make_pair(Desc, D));
204 /// addFlag - Add a flag that is true.
205 void DwarfUnit::addFlag(DIE &Die, dwarf::Attribute Attribute) {
206 if (DD->getDwarfVersion() >= 4)
207 Die.addValue(Attribute, dwarf::DW_FORM_flag_present, DIEIntegerOne);
209 Die.addValue(Attribute, dwarf::DW_FORM_flag, DIEIntegerOne);
212 /// addUInt - Add an unsigned integer attribute data and value.
214 void DwarfUnit::addUInt(DIE &Die, dwarf::Attribute Attribute,
215 Optional<dwarf::Form> Form, uint64_t Integer) {
217 Form = DIEInteger::BestForm(false, Integer);
218 DIEValue *Value = Integer == 1 ? DIEIntegerOne : new (DIEValueAllocator)
220 Die.addValue(Attribute, *Form, Value);
223 void DwarfUnit::addUInt(DIE &Block, dwarf::Form Form, uint64_t Integer) {
224 addUInt(Block, (dwarf::Attribute)0, Form, Integer);
227 /// addSInt - Add an signed integer attribute data and value.
229 void DwarfUnit::addSInt(DIE &Die, dwarf::Attribute Attribute,
230 Optional<dwarf::Form> Form, int64_t Integer) {
232 Form = DIEInteger::BestForm(true, Integer);
233 DIEValue *Value = new (DIEValueAllocator) DIEInteger(Integer);
234 Die.addValue(Attribute, *Form, Value);
237 void DwarfUnit::addSInt(DIELoc &Die, Optional<dwarf::Form> Form,
239 addSInt(Die, (dwarf::Attribute)0, Form, Integer);
242 /// addString - Add a string attribute data and value. We always emit a
243 /// reference to the string pool instead of immediate strings so that DIEs have
244 /// more predictable sizes. In the case of split dwarf we emit an index
245 /// into another table which gets us the static offset into the string
247 void DwarfUnit::addString(DIE &Die, dwarf::Attribute Attribute,
250 return addLocalString(Die, Attribute, String);
252 addIndexedString(Die, Attribute, String);
255 void DwarfUnit::addIndexedString(DIE &Die, dwarf::Attribute Attribute,
257 unsigned idx = DU->getStringPool().getIndex(*Asm, String);
258 DIEValue *Value = new (DIEValueAllocator) DIEInteger(idx);
259 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
260 Die.addValue(Attribute, dwarf::DW_FORM_GNU_str_index, Str);
263 /// addLocalString - Add a string attribute data and value. This is guaranteed
264 /// to be in the local string pool instead of indirected.
265 void DwarfUnit::addLocalString(DIE &Die, dwarf::Attribute Attribute,
267 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
268 MCSymbol *Symb = DU->getStringPool().getSymbol(*Asm, String);
270 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
271 Value = new (DIEValueAllocator) DIELabel(Symb);
273 Value = new (DIEValueAllocator)
274 DIEDelta(Symb, TLOF.getDwarfStrSection()->getBeginSymbol());
275 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
276 Die.addValue(Attribute, dwarf::DW_FORM_strp, Str);
279 /// addLabel - Add a Dwarf label attribute data and value.
281 void DwarfUnit::addLabel(DIE &Die, dwarf::Attribute Attribute, dwarf::Form Form,
282 const MCSymbol *Label) {
283 DIEValue *Value = new (DIEValueAllocator) DIELabel(Label);
284 Die.addValue(Attribute, Form, Value);
287 void DwarfUnit::addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label) {
288 addLabel(Die, (dwarf::Attribute)0, Form, Label);
291 /// addSectionOffset - Add an offset into a section attribute data and value.
293 void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
295 if (DD->getDwarfVersion() >= 4)
296 addUInt(Die, Attribute, dwarf::DW_FORM_sec_offset, Integer);
298 addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
301 unsigned DwarfTypeUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
302 return SplitLineTable ? SplitLineTable->getFile(DirName, FileName)
303 : getCU().getOrCreateSourceID(FileName, DirName);
306 /// addOpAddress - Add a dwarf op address data and value using the
307 /// form given and an op of either DW_FORM_addr or DW_FORM_GNU_addr_index.
309 void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) {
310 if (!DD->useSplitDwarf()) {
311 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
312 addLabel(Die, dwarf::DW_FORM_udata, Sym);
314 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_addr_index);
315 addUInt(Die, dwarf::DW_FORM_GNU_addr_index,
316 DD->getAddressPool().getIndex(Sym));
320 void DwarfUnit::addLabelDelta(DIE &Die, dwarf::Attribute Attribute,
321 const MCSymbol *Hi, const MCSymbol *Lo) {
322 DIEValue *Value = new (DIEValueAllocator) DIEDelta(Hi, Lo);
323 Die.addValue(Attribute, dwarf::DW_FORM_data4, Value);
326 /// addDIEEntry - Add a DIE attribute data and value.
328 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry) {
329 addDIEEntry(Die, Attribute, createDIEEntry(Entry));
332 void DwarfUnit::addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type) {
333 // Flag the type unit reference as a declaration so that if it contains
334 // members (implicit special members, static data member definitions, member
335 // declarations for definitions in this CU, etc) consumers don't get confused
336 // and think this is a full definition.
337 addFlag(Die, dwarf::DW_AT_declaration);
339 Die.addValue(dwarf::DW_AT_signature, dwarf::DW_FORM_ref_sig8,
340 new (DIEValueAllocator) DIETypeSignature(Type));
343 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
345 const DIE *DieCU = Die.getUnitOrNull();
346 const DIE *EntryCU = Entry->getEntry().getUnitOrNull();
348 // We assume that Die belongs to this CU, if it is not linked to any CU yet.
349 DieCU = &getUnitDie();
351 EntryCU = &getUnitDie();
352 Die.addValue(Attribute,
353 EntryCU == DieCU ? dwarf::DW_FORM_ref4 : dwarf::DW_FORM_ref_addr,
357 /// Create a DIE with the given Tag, add the DIE to its parent, and
358 /// call insertDIE if MD is not null.
359 DIE &DwarfUnit::createAndAddDIE(unsigned Tag, DIE &Parent, const DebugNode *N) {
360 assert(Tag != dwarf::DW_TAG_auto_variable &&
361 Tag != dwarf::DW_TAG_arg_variable);
362 Parent.addChild(make_unique<DIE>((dwarf::Tag)Tag));
363 DIE &Die = *Parent.getChildren().back();
369 /// addBlock - Add block data.
371 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Loc) {
372 Loc->ComputeSize(Asm);
373 DIELocs.push_back(Loc); // Memoize so we can call the destructor later on.
374 Die.addValue(Attribute, Loc->BestForm(DD->getDwarfVersion()), Loc);
377 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute,
379 Block->ComputeSize(Asm);
380 DIEBlocks.push_back(Block); // Memoize so we can call the destructor later on.
381 Die.addValue(Attribute, Block->BestForm(), Block);
384 /// addSourceLine - Add location information to specified debug information
386 void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, StringRef File,
387 StringRef Directory) {
391 unsigned FileID = getOrCreateSourceID(File, Directory);
392 assert(FileID && "Invalid file id");
393 addUInt(Die, dwarf::DW_AT_decl_file, None, FileID);
394 addUInt(Die, dwarf::DW_AT_decl_line, None, Line);
397 /// addSourceLine - Add location information to specified debug information
399 void DwarfUnit::addSourceLine(DIE &Die, DIVariable V) {
402 addSourceLine(Die, V->getLine(), V->getScope()->getFilename(),
403 V->getScope()->getDirectory());
406 /// addSourceLine - Add location information to specified debug information
408 void DwarfUnit::addSourceLine(DIE &Die, DIGlobalVariable G) {
411 addSourceLine(Die, G->getLine(), G->getFilename(), G->getDirectory());
414 /// addSourceLine - Add location information to specified debug information
416 void DwarfUnit::addSourceLine(DIE &Die, DISubprogram SP) {
419 addSourceLine(Die, SP->getLine(), SP->getFilename(), SP->getDirectory());
422 /// addSourceLine - Add location information to specified debug information
424 void DwarfUnit::addSourceLine(DIE &Die, DIType Ty) {
427 addSourceLine(Die, Ty->getLine(), Ty->getFilename(), Ty->getDirectory());
430 /// addSourceLine - Add location information to specified debug information
432 void DwarfUnit::addSourceLine(DIE &Die, DIObjCProperty Ty) {
435 addSourceLine(Die, Ty->getLine(), Ty->getFilename(), Ty->getDirectory());
438 /// addSourceLine - Add location information to specified debug information
440 void DwarfUnit::addSourceLine(DIE &Die, DINameSpace NS) {
441 addSourceLine(Die, NS->getLine(), NS->getFilename(), NS->getDirectory());
444 /// addRegisterOp - Add register operand.
445 bool DwarfUnit::addRegisterOpPiece(DIELoc &TheDie, unsigned Reg,
446 unsigned SizeInBits, unsigned OffsetInBits) {
447 DIEDwarfExpression Expr(*Asm, *this, TheDie);
448 Expr.AddMachineRegPiece(Reg, SizeInBits, OffsetInBits);
452 /// addRegisterOffset - Add register offset.
453 bool DwarfUnit::addRegisterOffset(DIELoc &TheDie, unsigned Reg,
455 DIEDwarfExpression Expr(*Asm, *this, TheDie);
456 return Expr.AddMachineRegIndirect(Reg, Offset);
459 /* Byref variables, in Blocks, are declared by the programmer as "SomeType
460 VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
461 gives the variable VarName either the struct, or a pointer to the struct, as
462 its type. This is necessary for various behind-the-scenes things the
463 compiler needs to do with by-reference variables in Blocks.
465 However, as far as the original *programmer* is concerned, the variable
466 should still have type 'SomeType', as originally declared.
468 The function getBlockByrefType dives into the __Block_byref_x_VarName
469 struct to find the original type of the variable, which is then assigned to
470 the variable's Debug Information Entry as its real type. So far, so good.
471 However now the debugger will expect the variable VarName to have the type
472 SomeType. So we need the location attribute for the variable to be an
473 expression that explains to the debugger how to navigate through the
474 pointers and struct to find the actual variable of type SomeType.
476 The following function does just that. We start by getting
477 the "normal" location for the variable. This will be the location
478 of either the struct __Block_byref_x_VarName or the pointer to the
479 struct __Block_byref_x_VarName.
481 The struct will look something like:
483 struct __Block_byref_x_VarName {
485 struct __Block_byref_x_VarName *forwarding;
486 ... <various other fields>
488 ... <maybe more fields>
491 If we are given the struct directly (as our starting point) we
492 need to tell the debugger to:
494 1). Add the offset of the forwarding field.
496 2). Follow that pointer to get the real __Block_byref_x_VarName
497 struct to use (the real one may have been copied onto the heap).
499 3). Add the offset for the field VarName, to find the actual variable.
501 If we started with a pointer to the struct, then we need to
502 dereference that pointer first, before the other steps.
503 Translating this into DWARF ops, we will need to append the following
504 to the current location description for the variable:
506 DW_OP_deref -- optional, if we start with a pointer
507 DW_OP_plus_uconst <forward_fld_offset>
509 DW_OP_plus_uconst <varName_fld_offset>
511 That is what this function does. */
513 /// addBlockByrefAddress - Start with the address based on the location
514 /// provided, and generate the DWARF information necessary to find the
515 /// actual Block variable (navigating the Block struct) based on the
516 /// starting location. Add the DWARF information to the die. For
517 /// more information, read large comment just above here.
519 void DwarfUnit::addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
520 dwarf::Attribute Attribute,
521 const MachineLocation &Location) {
522 DIType Ty = DV.getType();
524 uint16_t Tag = Ty->getTag();
525 bool isPointer = false;
527 StringRef varName = DV.getName();
529 if (Tag == dwarf::DW_TAG_pointer_type) {
530 DIDerivedType DTy = cast<MDDerivedType>(Ty);
531 TmpTy = resolve(DTy->getBaseType());
535 // Find the __forwarding field and the variable field in the __Block_byref
537 DIArray Fields = cast<MDCompositeTypeBase>(TmpTy)->getElements();
538 DIDerivedType varField;
539 DIDerivedType forwardingField;
541 for (unsigned i = 0, N = Fields.size(); i < N; ++i) {
542 DIDerivedType DT = cast<MDDerivedTypeBase>(Fields[i]);
543 StringRef fieldName = DT->getName();
544 if (fieldName == "__forwarding")
545 forwardingField = DT;
546 else if (fieldName == varName)
550 // Get the offsets for the forwarding field and the variable field.
551 unsigned forwardingFieldOffset = forwardingField->getOffsetInBits() >> 3;
552 unsigned varFieldOffset = varField->getOffsetInBits() >> 2;
554 // Decode the original location, and use that as the start of the byref
555 // variable's location.
556 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
559 if (Location.isReg())
560 validReg = addRegisterOpPiece(*Loc, Location.getReg());
562 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
567 // If we started with a pointer to the __Block_byref... struct, then
568 // the first thing we need to do is dereference the pointer (DW_OP_deref).
570 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
572 // Next add the offset for the '__forwarding' field:
573 // DW_OP_plus_uconst ForwardingFieldOffset. Note there's no point in
574 // adding the offset if it's 0.
575 if (forwardingFieldOffset > 0) {
576 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
577 addUInt(*Loc, dwarf::DW_FORM_udata, forwardingFieldOffset);
580 // Now dereference the __forwarding field to get to the real __Block_byref
581 // struct: DW_OP_deref.
582 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
584 // Now that we've got the real __Block_byref... struct, add the offset
585 // for the variable's field to get to the location of the actual variable:
586 // DW_OP_plus_uconst varFieldOffset. Again, don't add if it's 0.
587 if (varFieldOffset > 0) {
588 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
589 addUInt(*Loc, dwarf::DW_FORM_udata, varFieldOffset);
592 // Now attach the location information to the DIE.
593 addBlock(Die, Attribute, Loc);
596 /// Return true if type encoding is unsigned.
597 static bool isUnsignedDIType(DwarfDebug *DD, DIType Ty) {
598 if (DIDerivedType DTy = dyn_cast<MDDerivedTypeBase>(Ty)) {
599 dwarf::Tag T = (dwarf::Tag)Ty->getTag();
600 // Encode pointer constants as unsigned bytes. This is used at least for
601 // null pointer constant emission.
602 // (Pieces of) aggregate types that get hacked apart by SROA may also be
603 // represented by a constant. Encode them as unsigned bytes.
604 // FIXME: reference and rvalue_reference /probably/ shouldn't be allowed
605 // here, but accept them for now due to a bug in SROA producing bogus
607 if (T == dwarf::DW_TAG_array_type ||
608 T == dwarf::DW_TAG_class_type ||
609 T == dwarf::DW_TAG_pointer_type ||
610 T == dwarf::DW_TAG_ptr_to_member_type ||
611 T == dwarf::DW_TAG_reference_type ||
612 T == dwarf::DW_TAG_rvalue_reference_type ||
613 T == dwarf::DW_TAG_structure_type ||
614 T == dwarf::DW_TAG_union_type)
616 assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
617 T == dwarf::DW_TAG_volatile_type ||
618 T == dwarf::DW_TAG_restrict_type ||
619 T == dwarf::DW_TAG_enumeration_type);
620 if (DITypeRef Deriv = DTy->getBaseType())
621 return isUnsignedDIType(DD, DD->resolve(Deriv));
622 // FIXME: Enums without a fixed underlying type have unknown signedness
623 // here, leading to incorrectly emitted constants.
624 assert(DTy->getTag() == dwarf::DW_TAG_enumeration_type);
628 DIBasicType BTy = cast<MDBasicType>(Ty);
629 unsigned Encoding = BTy->getEncoding();
630 assert((Encoding == dwarf::DW_ATE_unsigned ||
631 Encoding == dwarf::DW_ATE_unsigned_char ||
632 Encoding == dwarf::DW_ATE_signed ||
633 Encoding == dwarf::DW_ATE_signed_char ||
634 Encoding == dwarf::DW_ATE_float || Encoding == dwarf::DW_ATE_UTF ||
635 Encoding == dwarf::DW_ATE_boolean ||
636 (Ty->getTag() == dwarf::DW_TAG_unspecified_type &&
637 Ty->getName() == "decltype(nullptr)")) &&
638 "Unsupported encoding");
639 return Encoding == dwarf::DW_ATE_unsigned ||
640 Encoding == dwarf::DW_ATE_unsigned_char ||
641 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean ||
642 Ty->getTag() == dwarf::DW_TAG_unspecified_type;
645 /// If this type is derived from a base type then return base type size.
646 static uint64_t getBaseTypeSize(DwarfDebug *DD, DIDerivedType Ty) {
647 unsigned Tag = Ty->getTag();
649 if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
650 Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
651 Tag != dwarf::DW_TAG_restrict_type)
652 return Ty->getSizeInBits();
654 auto *BaseType = DD->resolve(Ty->getBaseType());
656 assert(BaseType && "Unexpected invalid base type");
658 // If this is a derived type, go ahead and get the base type, unless it's a
659 // reference then it's just the size of the field. Pointer types have no need
660 // of this since they're a different type of qualification on the type.
661 if (BaseType->getTag() == dwarf::DW_TAG_reference_type ||
662 BaseType->getTag() == dwarf::DW_TAG_rvalue_reference_type)
663 return Ty->getSizeInBits();
665 if (auto *DT = dyn_cast<MDDerivedTypeBase>(BaseType))
666 return getBaseTypeSize(DD, DT);
668 return BaseType->getSizeInBits();
671 /// addConstantFPValue - Add constant value entry in variable DIE.
672 void DwarfUnit::addConstantFPValue(DIE &Die, const MachineOperand &MO) {
673 assert(MO.isFPImm() && "Invalid machine operand!");
674 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
675 APFloat FPImm = MO.getFPImm()->getValueAPF();
677 // Get the raw data form of the floating point.
678 const APInt FltVal = FPImm.bitcastToAPInt();
679 const char *FltPtr = (const char *)FltVal.getRawData();
681 int NumBytes = FltVal.getBitWidth() / 8; // 8 bits per byte.
682 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
683 int Incr = (LittleEndian ? 1 : -1);
684 int Start = (LittleEndian ? 0 : NumBytes - 1);
685 int Stop = (LittleEndian ? NumBytes : -1);
687 // Output the constant to DWARF one byte at a time.
688 for (; Start != Stop; Start += Incr)
689 addUInt(*Block, dwarf::DW_FORM_data1, (unsigned char)0xFF & FltPtr[Start]);
691 addBlock(Die, dwarf::DW_AT_const_value, Block);
694 /// addConstantFPValue - Add constant value entry in variable DIE.
695 void DwarfUnit::addConstantFPValue(DIE &Die, const ConstantFP *CFP) {
696 // Pass this down to addConstantValue as an unsigned bag of bits.
697 addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
700 /// addConstantValue - Add constant value entry in variable DIE.
701 void DwarfUnit::addConstantValue(DIE &Die, const ConstantInt *CI, DIType Ty) {
702 addConstantValue(Die, CI->getValue(), Ty);
705 /// addConstantValue - Add constant value entry in variable DIE.
706 void DwarfUnit::addConstantValue(DIE &Die, const MachineOperand &MO,
708 assert(MO.isImm() && "Invalid machine operand!");
710 addConstantValue(Die, isUnsignedDIType(DD, Ty), MO.getImm());
713 void DwarfUnit::addConstantValue(DIE &Die, bool Unsigned, uint64_t Val) {
714 // FIXME: This is a bit conservative/simple - it emits negative values always
715 // sign extended to 64 bits rather than minimizing the number of bytes.
716 addUInt(Die, dwarf::DW_AT_const_value,
717 Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata, Val);
720 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, DIType Ty) {
721 addConstantValue(Die, Val, isUnsignedDIType(DD, Ty));
724 // addConstantValue - Add constant value entry in variable DIE.
725 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
726 unsigned CIBitWidth = Val.getBitWidth();
727 if (CIBitWidth <= 64) {
728 addConstantValue(Die, Unsigned,
729 Unsigned ? Val.getZExtValue() : Val.getSExtValue());
733 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
735 // Get the raw data form of the large APInt.
736 const uint64_t *Ptr64 = Val.getRawData();
738 int NumBytes = Val.getBitWidth() / 8; // 8 bits per byte.
739 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
741 // Output the constant to DWARF one byte at a time.
742 for (int i = 0; i < NumBytes; i++) {
745 c = Ptr64[i / 8] >> (8 * (i & 7));
747 c = Ptr64[(NumBytes - 1 - i) / 8] >> (8 * ((NumBytes - 1 - i) & 7));
748 addUInt(*Block, dwarf::DW_FORM_data1, c);
751 addBlock(Die, dwarf::DW_AT_const_value, Block);
754 // Add a linkage name to the DIE.
755 void DwarfUnit::addLinkageName(DIE &Die, StringRef LinkageName) {
756 if (!LinkageName.empty())
758 DD->getDwarfVersion() >= 4 ? dwarf::DW_AT_linkage_name
759 : dwarf::DW_AT_MIPS_linkage_name,
760 GlobalValue::getRealLinkageName(LinkageName));
763 /// addTemplateParams - Add template parameters into buffer.
764 void DwarfUnit::addTemplateParams(DIE &Buffer, DIArray TParams) {
765 // Add template parameters.
766 for (const auto *Element : TParams) {
767 if (auto *TTP = dyn_cast<MDTemplateTypeParameter>(Element))
768 constructTemplateTypeParameterDIE(Buffer, TTP);
769 else if (auto *TVP = dyn_cast<MDTemplateValueParameter>(Element))
770 constructTemplateValueParameterDIE(Buffer, TVP);
774 /// getOrCreateContextDIE - Get context owner's DIE.
775 DIE *DwarfUnit::getOrCreateContextDIE(DIScope Context) {
776 if (!Context || isa<MDFile>(Context))
777 return &getUnitDie();
778 if (auto *T = dyn_cast<MDType>(Context))
779 return getOrCreateTypeDIE(T);
780 if (auto *NS = dyn_cast<MDNamespace>(Context))
781 return getOrCreateNameSpace(NS);
782 if (auto *SP = dyn_cast<MDSubprogram>(Context))
783 return getOrCreateSubprogramDIE(SP);
784 return getDIE(Context);
787 DIE *DwarfUnit::createTypeDIE(DICompositeType Ty) {
788 DIScope Context = resolve(Ty->getScope());
789 DIE *ContextDIE = getOrCreateContextDIE(Context);
791 if (DIE *TyDIE = getDIE(Ty))
795 DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
797 constructTypeDIE(TyDIE, Ty);
799 updateAcceleratorTables(Context, Ty, TyDIE);
803 /// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
805 DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
809 auto *Ty = cast<MDType>(TyNode);
810 assert(Ty == resolve(Ty->getRef()) &&
811 "type was not uniqued, possible ODR violation.");
813 // DW_TAG_restrict_type is not supported in DWARF2
814 if (Ty->getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
815 return getOrCreateTypeDIE(
816 resolve(DITypeRef(cast<MDDerivedType>(Ty)->getBaseType())));
818 // Construct the context before querying for the existence of the DIE in case
819 // such construction creates the DIE.
820 DIScope Context = resolve(Ty->getScope());
821 DIE *ContextDIE = getOrCreateContextDIE(Context);
824 if (DIE *TyDIE = getDIE(Ty))
828 DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
830 updateAcceleratorTables(Context, Ty, TyDIE);
832 if (auto *BT = dyn_cast<MDBasicType>(Ty))
833 constructTypeDIE(TyDIE, BT);
834 else if (DICompositeType CTy = dyn_cast<MDCompositeTypeBase>(Ty)) {
835 if (GenerateDwarfTypeUnits && !Ty->isForwardDecl())
836 if (MDString *TypeId = CTy->getRawIdentifier()) {
837 DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);
838 // Skip updating the accelerator tables since this is not the full type.
841 constructTypeDIE(TyDIE, CTy);
843 constructTypeDIE(TyDIE, cast<MDDerivedType>(Ty));
849 void DwarfUnit::updateAcceleratorTables(DIScope Context, DIType Ty,
851 if (!Ty->getName().empty() && !Ty->isForwardDecl()) {
852 bool IsImplementation = 0;
853 if (auto *CT = dyn_cast<MDCompositeTypeBase>(Ty)) {
854 // A runtime language of 0 actually means C/C++ and that any
855 // non-negative value is some version of Objective-C/C++.
856 IsImplementation = CT->getRuntimeLang() == 0 || CT->isObjcClassComplete();
858 unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
859 DD->addAccelType(Ty->getName(), TyDIE, Flags);
861 if (!Context || isa<MDCompileUnit>(Context) || isa<MDFile>(Context) ||
862 isa<MDNamespace>(Context))
863 addGlobalType(Ty, TyDIE, Context);
867 /// addType - Add a new type attribute to the specified entity.
868 void DwarfUnit::addType(DIE &Entity, DIType Ty, dwarf::Attribute Attribute) {
869 assert(Ty && "Trying to add a type that doesn't exist?");
871 // Check for pre-existence.
872 DIEEntry *Entry = getDIEEntry(Ty);
873 // If it exists then use the existing value.
875 addDIEEntry(Entity, Attribute, Entry);
880 DIE *Buffer = getOrCreateTypeDIE(Ty);
883 Entry = createDIEEntry(*Buffer);
884 insertDIEEntry(Ty, Entry);
885 addDIEEntry(Entity, Attribute, Entry);
888 /// getParentContextString - Walks the metadata parent chain in a language
889 /// specific manner (using the compile unit language) and returns
890 /// it as a string. This is done at the metadata level because DIEs may
891 /// not currently have been added to the parent context and walking the
892 /// DIEs looking for names is more expensive than walking the metadata.
893 std::string DwarfUnit::getParentContextString(DIScope Context) const {
897 // FIXME: Decide whether to implement this for non-C++ languages.
898 if (getLanguage() != dwarf::DW_LANG_C_plus_plus)
902 SmallVector<DIScope, 1> Parents;
903 while (!isa<MDCompileUnit>(Context)) {
904 Parents.push_back(Context);
905 if (Context->getScope())
906 Context = resolve(Context->getScope());
908 // Structure, etc types will have a NULL context if they're at the top
913 // Reverse iterate over our list to go from the outermost construct to the
915 for (SmallVectorImpl<DIScope>::reverse_iterator I = Parents.rbegin(),
918 const MDScope *Ctx = *I;
919 StringRef Name = Ctx->getName();
920 if (Name.empty() && isa<MDNamespace>(Ctx))
921 Name = "(anonymous namespace)";
930 /// constructTypeDIE - Construct basic type die from DIBasicType.
931 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIBasicType BTy) {
932 // Get core information.
933 StringRef Name = BTy->getName();
934 // Add name if not anonymous or intermediate type.
936 addString(Buffer, dwarf::DW_AT_name, Name);
938 // An unspecified type only has a name attribute.
939 if (BTy->getTag() == dwarf::DW_TAG_unspecified_type)
942 addUInt(Buffer, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
945 uint64_t Size = BTy->getSizeInBits() >> 3;
946 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
949 /// constructTypeDIE - Construct derived type die from DIDerivedType.
950 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIDerivedType DTy) {
951 // Get core information.
952 StringRef Name = DTy->getName();
953 uint64_t Size = DTy->getSizeInBits() >> 3;
954 uint16_t Tag = Buffer.getTag();
956 // Map to main type, void will not have a type.
957 DIType FromTy = resolve(DTy->getBaseType());
959 addType(Buffer, FromTy);
961 // Add name if not anonymous or intermediate type.
963 addString(Buffer, dwarf::DW_AT_name, Name);
965 // Add size if non-zero (derived types might be zero-sized.)
966 if (Size && Tag != dwarf::DW_TAG_pointer_type
967 && Tag != dwarf::DW_TAG_ptr_to_member_type)
968 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
970 if (Tag == dwarf::DW_TAG_ptr_to_member_type)
972 Buffer, dwarf::DW_AT_containing_type,
973 *getOrCreateTypeDIE(resolve(cast<MDDerivedType>(DTy)->getClassType())));
974 // Add source line info if available and TyDesc is not a forward declaration.
975 if (!DTy->isForwardDecl())
976 addSourceLine(Buffer, DTy);
979 /// constructSubprogramArguments - Construct function argument DIEs.
980 void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DITypeArray Args) {
981 for (unsigned i = 1, N = Args.size(); i < N; ++i) {
982 DIType Ty = resolve(Args[i]);
984 assert(i == N-1 && "Unspecified parameter must be the last argument");
985 createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
987 DIE &Arg = createAndAddDIE(dwarf::DW_TAG_formal_parameter, Buffer);
989 if (Ty->isArtificial())
990 addFlag(Arg, dwarf::DW_AT_artificial);
995 /// constructTypeDIE - Construct type DIE from DICompositeType.
996 void DwarfUnit::constructTypeDIE(DIE &Buffer, DICompositeType CTy) {
997 // Add name if not anonymous or intermediate type.
998 StringRef Name = CTy->getName();
1000 uint64_t Size = CTy->getSizeInBits() >> 3;
1001 uint16_t Tag = Buffer.getTag();
1004 case dwarf::DW_TAG_array_type:
1005 constructArrayTypeDIE(Buffer, CTy);
1007 case dwarf::DW_TAG_enumeration_type:
1008 constructEnumTypeDIE(Buffer, CTy);
1010 case dwarf::DW_TAG_subroutine_type: {
1011 // Add return type. A void return won't have a type.
1012 auto Elements = cast<MDSubroutineType>(CTy)->getTypeArray();
1013 if (Elements.size())
1014 if (auto RTy = resolve(Elements[0]))
1015 addType(Buffer, RTy);
1017 bool isPrototyped = true;
1018 if (Elements.size() == 2 && !Elements[1])
1019 isPrototyped = false;
1021 constructSubprogramArguments(Buffer, Elements);
1023 // Add prototype flag if we're dealing with a C language and the
1024 // function has been prototyped.
1025 uint16_t Language = getLanguage();
1027 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1028 Language == dwarf::DW_LANG_ObjC))
1029 addFlag(Buffer, dwarf::DW_AT_prototyped);
1031 if (CTy->isLValueReference())
1032 addFlag(Buffer, dwarf::DW_AT_reference);
1034 if (CTy->isRValueReference())
1035 addFlag(Buffer, dwarf::DW_AT_rvalue_reference);
1037 case dwarf::DW_TAG_structure_type:
1038 case dwarf::DW_TAG_union_type:
1039 case dwarf::DW_TAG_class_type: {
1040 // Add elements to structure type.
1041 DIArray Elements = CTy->getElements();
1042 for (const auto *Element : Elements) {
1045 if (auto *SP = dyn_cast<MDSubprogram>(Element))
1046 getOrCreateSubprogramDIE(SP);
1047 else if (DIDerivedType DDTy = dyn_cast<MDDerivedTypeBase>(Element)) {
1048 if (DDTy->getTag() == dwarf::DW_TAG_friend) {
1049 DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
1050 addType(ElemDie, resolve(DDTy->getBaseType()), dwarf::DW_AT_friend);
1051 } else if (DDTy->isStaticMember()) {
1052 getOrCreateStaticMemberDIE(DDTy);
1054 constructMemberDIE(Buffer, DDTy);
1056 } else if (DIObjCProperty Property = dyn_cast<MDObjCProperty>(Element)) {
1057 DIE &ElemDie = createAndAddDIE(Property->getTag(), Buffer);
1058 StringRef PropertyName = Property->getName();
1059 addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
1060 if (Property->getType())
1061 addType(ElemDie, Property->getType());
1062 addSourceLine(ElemDie, Property);
1063 StringRef GetterName = Property->getGetterName();
1064 if (!GetterName.empty())
1065 addString(ElemDie, dwarf::DW_AT_APPLE_property_getter, GetterName);
1066 StringRef SetterName = Property->getSetterName();
1067 if (!SetterName.empty())
1068 addString(ElemDie, dwarf::DW_AT_APPLE_property_setter, SetterName);
1069 if (unsigned PropertyAttributes = Property->getAttributes())
1070 addUInt(ElemDie, dwarf::DW_AT_APPLE_property_attribute, None,
1071 PropertyAttributes);
1073 DIEEntry *Entry = getDIEEntry(Element);
1075 Entry = createDIEEntry(ElemDie);
1076 insertDIEEntry(Element, Entry);
1081 if (CTy->isAppleBlockExtension())
1082 addFlag(Buffer, dwarf::DW_AT_APPLE_block);
1084 // This is outside the DWARF spec, but GDB expects a DW_AT_containing_type
1085 // inside C++ composite types to point to the base class with the vtable.
1086 if (DICompositeType ContainingType =
1087 dyn_cast_or_null<MDCompositeType>(resolve(CTy->getVTableHolder())))
1088 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
1089 *getOrCreateTypeDIE(ContainingType));
1091 if (CTy->isObjcClassComplete())
1092 addFlag(Buffer, dwarf::DW_AT_APPLE_objc_complete_type);
1094 // Add template parameters to a class, structure or union types.
1095 // FIXME: The support isn't in the metadata for this yet.
1096 if (Tag == dwarf::DW_TAG_class_type ||
1097 Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
1098 addTemplateParams(Buffer, CTy->getTemplateParams());
1106 // Add name if not anonymous or intermediate type.
1108 addString(Buffer, dwarf::DW_AT_name, Name);
1110 if (Tag == dwarf::DW_TAG_enumeration_type ||
1111 Tag == dwarf::DW_TAG_class_type || Tag == dwarf::DW_TAG_structure_type ||
1112 Tag == dwarf::DW_TAG_union_type) {
1113 // Add size if non-zero (derived types might be zero-sized.)
1114 // TODO: Do we care about size for enum forward declarations?
1116 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
1117 else if (!CTy->isForwardDecl())
1118 // Add zero size if it is not a forward declaration.
1119 addUInt(Buffer, dwarf::DW_AT_byte_size, None, 0);
1121 // If we're a forward decl, say so.
1122 if (CTy->isForwardDecl())
1123 addFlag(Buffer, dwarf::DW_AT_declaration);
1125 // Add source line info if available.
1126 if (!CTy->isForwardDecl())
1127 addSourceLine(Buffer, CTy);
1129 // No harm in adding the runtime language to the declaration.
1130 unsigned RLang = CTy->getRuntimeLang();
1132 addUInt(Buffer, dwarf::DW_AT_APPLE_runtime_class, dwarf::DW_FORM_data1,
1137 /// constructTemplateTypeParameterDIE - Construct new DIE for the given
1138 /// DITemplateTypeParameter.
1139 void DwarfUnit::constructTemplateTypeParameterDIE(DIE &Buffer,
1140 DITemplateTypeParameter TP) {
1142 createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
1143 // Add the type if it exists, it could be void and therefore no type.
1145 addType(ParamDIE, resolve(TP->getType()));
1146 if (!TP->getName().empty())
1147 addString(ParamDIE, dwarf::DW_AT_name, TP->getName());
1150 /// constructTemplateValueParameterDIE - Construct new DIE for the given
1151 /// DITemplateValueParameter.
1153 DwarfUnit::constructTemplateValueParameterDIE(DIE &Buffer,
1154 DITemplateValueParameter VP) {
1155 DIE &ParamDIE = createAndAddDIE(VP->getTag(), Buffer);
1157 // Add the type if there is one, template template and template parameter
1158 // packs will not have a type.
1159 if (VP->getTag() == dwarf::DW_TAG_template_value_parameter)
1160 addType(ParamDIE, resolve(VP->getType()));
1161 if (!VP->getName().empty())
1162 addString(ParamDIE, dwarf::DW_AT_name, VP->getName());
1163 if (Metadata *Val = VP->getValue()) {
1164 if (ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(Val))
1165 addConstantValue(ParamDIE, CI, resolve(VP->getType()));
1166 else if (GlobalValue *GV = mdconst::dyn_extract<GlobalValue>(Val)) {
1167 // For declaration non-type template parameters (such as global values and
1169 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
1170 addOpAddress(*Loc, Asm->getSymbol(GV));
1171 // Emit DW_OP_stack_value to use the address as the immediate value of the
1172 // parameter, rather than a pointer to it.
1173 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_stack_value);
1174 addBlock(ParamDIE, dwarf::DW_AT_location, Loc);
1175 } else if (VP->getTag() == dwarf::DW_TAG_GNU_template_template_param) {
1176 assert(isa<MDString>(Val));
1177 addString(ParamDIE, dwarf::DW_AT_GNU_template_name,
1178 cast<MDString>(Val)->getString());
1179 } else if (VP->getTag() == dwarf::DW_TAG_GNU_template_parameter_pack) {
1180 addTemplateParams(ParamDIE, cast<MDTuple>(Val));
1185 /// getOrCreateNameSpace - Create a DIE for DINameSpace.
1186 DIE *DwarfUnit::getOrCreateNameSpace(DINameSpace NS) {
1187 // Construct the context before querying for the existence of the DIE in case
1188 // such construction creates the DIE.
1189 DIE *ContextDIE = getOrCreateContextDIE(NS->getScope());
1191 if (DIE *NDie = getDIE(NS))
1193 DIE &NDie = createAndAddDIE(dwarf::DW_TAG_namespace, *ContextDIE, NS);
1195 StringRef Name = NS->getName();
1197 addString(NDie, dwarf::DW_AT_name, NS->getName());
1199 Name = "(anonymous namespace)";
1200 DD->addAccelNamespace(Name, NDie);
1201 addGlobalName(Name, NDie, NS->getScope());
1202 addSourceLine(NDie, NS);
1206 /// getOrCreateSubprogramDIE - Create new DIE using SP.
1207 DIE *DwarfUnit::getOrCreateSubprogramDIE(DISubprogram SP, bool Minimal) {
1208 // Construct the context before querying for the existence of the DIE in case
1209 // such construction creates the DIE (as is the case for member function
1212 Minimal ? &getUnitDie() : getOrCreateContextDIE(resolve(SP->getScope()));
1214 if (DIE *SPDie = getDIE(SP))
1217 if (auto *SPDecl = SP->getDeclaration()) {
1219 // Add subprogram definitions to the CU die directly.
1220 ContextDIE = &getUnitDie();
1221 // Build the decl now to ensure it precedes the definition.
1222 getOrCreateSubprogramDIE(SPDecl);
1226 // DW_TAG_inlined_subroutine may refer to this DIE.
1227 DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
1229 // Stop here and fill this in later, depending on whether or not this
1230 // subprogram turns out to have inlined instances or not.
1231 if (SP->isDefinition())
1234 applySubprogramAttributes(SP, SPDie);
1238 bool DwarfUnit::applySubprogramDefinitionAttributes(DISubprogram SP,
1240 DIE *DeclDie = nullptr;
1241 StringRef DeclLinkageName;
1242 if (auto *SPDecl = SP->getDeclaration()) {
1243 DeclDie = getDIE(SPDecl);
1244 assert(DeclDie && "This DIE should've already been constructed when the "
1245 "definition DIE was created in "
1246 "getOrCreateSubprogramDIE");
1247 DeclLinkageName = SPDecl->getLinkageName();
1250 // Add function template parameters.
1251 addTemplateParams(SPDie, SP->getTemplateParams());
1253 // Add the linkage name if we have one and it isn't in the Decl.
1254 StringRef LinkageName = SP->getLinkageName();
1255 assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
1256 LinkageName == DeclLinkageName) &&
1257 "decl has a linkage name and it is different");
1258 if (DeclLinkageName.empty())
1259 addLinkageName(SPDie, LinkageName);
1264 // Refer to the function declaration where all the other attributes will be
1266 addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
1270 void DwarfUnit::applySubprogramAttributes(DISubprogram SP, DIE &SPDie,
1273 if (applySubprogramDefinitionAttributes(SP, SPDie))
1276 // Constructors and operators for anonymous aggregates do not have names.
1277 if (!SP->getName().empty())
1278 addString(SPDie, dwarf::DW_AT_name, SP->getName());
1280 // Skip the rest of the attributes under -gmlt to save space.
1284 addSourceLine(SPDie, SP);
1286 // Add the prototype if we have a prototype and we have a C like
1288 uint16_t Language = getLanguage();
1289 if (SP->isPrototyped() &&
1290 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1291 Language == dwarf::DW_LANG_ObjC))
1292 addFlag(SPDie, dwarf::DW_AT_prototyped);
1294 DISubroutineType SPTy = SP->getType();
1295 assert(SPTy->getTag() == dwarf::DW_TAG_subroutine_type &&
1296 "the type of a subprogram should be a subroutine");
1298 auto Args = SPTy->getTypeArray();
1299 // Add a return type. If this is a type like a C/C++ void type we don't add a
1302 if (auto Ty = resolve(Args[0]))
1305 unsigned VK = SP->getVirtuality();
1307 addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1, VK);
1308 DIELoc *Block = getDIELoc();
1309 addUInt(*Block, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1310 addUInt(*Block, dwarf::DW_FORM_udata, SP->getVirtualIndex());
1311 addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
1312 ContainingTypeMap.insert(
1313 std::make_pair(&SPDie, resolve(SP->getContainingType())));
1316 if (!SP->isDefinition()) {
1317 addFlag(SPDie, dwarf::DW_AT_declaration);
1319 // Add arguments. Do not add arguments for subprogram definition. They will
1320 // be handled while processing variables.
1321 constructSubprogramArguments(SPDie, Args);
1324 if (SP->isArtificial())
1325 addFlag(SPDie, dwarf::DW_AT_artificial);
1327 if (!SP->isLocalToUnit())
1328 addFlag(SPDie, dwarf::DW_AT_external);
1330 if (SP->isOptimized())
1331 addFlag(SPDie, dwarf::DW_AT_APPLE_optimized);
1333 if (unsigned isa = Asm->getISAEncoding())
1334 addUInt(SPDie, dwarf::DW_AT_APPLE_isa, dwarf::DW_FORM_flag, isa);
1336 if (SP->isLValueReference())
1337 addFlag(SPDie, dwarf::DW_AT_reference);
1339 if (SP->isRValueReference())
1340 addFlag(SPDie, dwarf::DW_AT_rvalue_reference);
1342 if (SP->isProtected())
1343 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1344 dwarf::DW_ACCESS_protected);
1345 else if (SP->isPrivate())
1346 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1347 dwarf::DW_ACCESS_private);
1348 else if (SP->isPublic())
1349 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1350 dwarf::DW_ACCESS_public);
1352 if (SP->isExplicit())
1353 addFlag(SPDie, dwarf::DW_AT_explicit);
1356 /// constructSubrangeDIE - Construct subrange DIE from DISubrange.
1357 void DwarfUnit::constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy) {
1358 DIE &DW_Subrange = createAndAddDIE(dwarf::DW_TAG_subrange_type, Buffer);
1359 addDIEEntry(DW_Subrange, dwarf::DW_AT_type, *IndexTy);
1361 // The LowerBound value defines the lower bounds which is typically zero for
1362 // C/C++. The Count value is the number of elements. Values are 64 bit. If
1363 // Count == -1 then the array is unbounded and we do not emit
1364 // DW_AT_lower_bound and DW_AT_count attributes.
1365 int64_t LowerBound = SR->getLowerBound();
1366 int64_t DefaultLowerBound = getDefaultLowerBound();
1367 int64_t Count = SR->getCount();
1369 if (DefaultLowerBound == -1 || LowerBound != DefaultLowerBound)
1370 addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, None, LowerBound);
1373 // FIXME: An unbounded array should reference the expression that defines
1375 addUInt(DW_Subrange, dwarf::DW_AT_count, None, Count);
1378 DIE *DwarfUnit::getIndexTyDie() {
1381 // Construct an integer type to use for indexes.
1382 IndexTyDie = &createAndAddDIE(dwarf::DW_TAG_base_type, UnitDie);
1383 addString(*IndexTyDie, dwarf::DW_AT_name, "sizetype");
1384 addUInt(*IndexTyDie, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
1385 addUInt(*IndexTyDie, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
1386 dwarf::DW_ATE_unsigned);
1390 /// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
1391 void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, DICompositeType CTy) {
1392 if (CTy->isVector())
1393 addFlag(Buffer, dwarf::DW_AT_GNU_vector);
1395 // Emit the element type.
1396 addType(Buffer, resolve(CTy->getBaseType()));
1398 // Get an anonymous type for index type.
1399 // FIXME: This type should be passed down from the front end
1400 // as different languages may have different sizes for indexes.
1401 DIE *IdxTy = getIndexTyDie();
1403 // Add subranges to array type.
1404 DIArray Elements = CTy->getElements();
1405 for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
1406 // FIXME: Should this really be such a loose cast?
1407 if (auto *Element = dyn_cast_or_null<DebugNode>(Elements[i]))
1408 if (Element->getTag() == dwarf::DW_TAG_subrange_type)
1409 constructSubrangeDIE(Buffer, cast<MDSubrange>(Element), IdxTy);
1413 /// constructEnumTypeDIE - Construct an enum type DIE from DICompositeType.
1414 void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, DICompositeType CTy) {
1415 DIArray Elements = CTy->getElements();
1417 // Add enumerators to enumeration type.
1418 for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
1419 auto *Enum = dyn_cast_or_null<MDEnumerator>(Elements[i]);
1421 DIE &Enumerator = createAndAddDIE(dwarf::DW_TAG_enumerator, Buffer);
1422 StringRef Name = Enum->getName();
1423 addString(Enumerator, dwarf::DW_AT_name, Name);
1424 int64_t Value = Enum->getValue();
1425 addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
1429 DIType DTy = resolve(CTy->getBaseType());
1431 addType(Buffer, DTy);
1432 addFlag(Buffer, dwarf::DW_AT_enum_class);
1436 /// constructContainingTypeDIEs - Construct DIEs for types that contain
1438 void DwarfUnit::constructContainingTypeDIEs() {
1439 for (auto CI = ContainingTypeMap.begin(), CE = ContainingTypeMap.end();
1441 DIE &SPDie = *CI->first;
1442 const DebugNode *D = CI->second;
1445 DIE *NDie = getDIE(D);
1448 addDIEEntry(SPDie, dwarf::DW_AT_containing_type, *NDie);
1452 /// constructMemberDIE - Construct member DIE from DIDerivedType.
1453 void DwarfUnit::constructMemberDIE(DIE &Buffer, DIDerivedType DT_) {
1454 // Downcast to MDDerivedType.
1455 const MDDerivedType *DT = cast<MDDerivedType>(DT_);
1457 DIE &MemberDie = createAndAddDIE(DT->getTag(), Buffer);
1458 StringRef Name = DT->getName();
1460 addString(MemberDie, dwarf::DW_AT_name, Name);
1462 addType(MemberDie, resolve(DT->getBaseType()));
1464 addSourceLine(MemberDie, DT);
1466 if (DT->getTag() == dwarf::DW_TAG_inheritance && DT->isVirtual()) {
1468 // For C++, virtual base classes are not at fixed offset. Use following
1469 // expression to extract appropriate offset from vtable.
1470 // BaseAddr = ObAddr + *((*ObAddr) - Offset)
1472 DIELoc *VBaseLocationDie = new (DIEValueAllocator) DIELoc();
1473 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
1474 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1475 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1476 addUInt(*VBaseLocationDie, dwarf::DW_FORM_udata, DT->getOffsetInBits());
1477 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
1478 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1479 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
1481 addBlock(MemberDie, dwarf::DW_AT_data_member_location, VBaseLocationDie);
1483 uint64_t Size = DT->getSizeInBits();
1484 uint64_t FieldSize = getBaseTypeSize(DD, DT);
1485 uint64_t OffsetInBytes;
1487 if (FieldSize && Size != FieldSize) {
1488 // Handle bitfield, assume bytes are 8 bits.
1489 addUInt(MemberDie, dwarf::DW_AT_byte_size, None, FieldSize/8);
1490 addUInt(MemberDie, dwarf::DW_AT_bit_size, None, Size);
1492 uint64_t Offset = DT->getOffsetInBits();
1493 uint64_t AlignMask = ~(DT->getAlignInBits() - 1);
1494 uint64_t HiMark = (Offset + FieldSize) & AlignMask;
1495 uint64_t FieldOffset = (HiMark - FieldSize);
1496 Offset -= FieldOffset;
1498 // Maybe we need to work from the other end.
1499 if (Asm->getDataLayout().isLittleEndian())
1500 Offset = FieldSize - (Offset + Size);
1501 addUInt(MemberDie, dwarf::DW_AT_bit_offset, None, Offset);
1503 // Here DW_AT_data_member_location points to the anonymous
1504 // field that includes this bit field.
1505 OffsetInBytes = FieldOffset >> 3;
1507 // This is not a bitfield.
1508 OffsetInBytes = DT->getOffsetInBits() >> 3;
1510 if (DD->getDwarfVersion() <= 2) {
1511 DIELoc *MemLocationDie = new (DIEValueAllocator) DIELoc();
1512 addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
1513 addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes);
1514 addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie);
1516 addUInt(MemberDie, dwarf::DW_AT_data_member_location, None,
1520 if (DT->isProtected())
1521 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1522 dwarf::DW_ACCESS_protected);
1523 else if (DT->isPrivate())
1524 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1525 dwarf::DW_ACCESS_private);
1526 // Otherwise C++ member and base classes are considered public.
1527 else if (DT->isPublic())
1528 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1529 dwarf::DW_ACCESS_public);
1530 if (DT->isVirtual())
1531 addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1,
1532 dwarf::DW_VIRTUALITY_virtual);
1534 // Objective-C properties.
1535 if (MDNode *PNode = DT->getObjCProperty())
1536 if (DIEEntry *PropertyDie = getDIEEntry(PNode))
1537 MemberDie.addValue(dwarf::DW_AT_APPLE_property, dwarf::DW_FORM_ref4,
1540 if (DT->isArtificial())
1541 addFlag(MemberDie, dwarf::DW_AT_artificial);
1544 /// getOrCreateStaticMemberDIE - Create new DIE for C++ static member.
1545 DIE *DwarfUnit::getOrCreateStaticMemberDIE(DIDerivedType DT_) {
1546 const MDDerivedType *DT = cast_or_null<MDDerivedType>(DT_);
1550 // Construct the context before querying for the existence of the DIE in case
1551 // such construction creates the DIE.
1552 DIE *ContextDIE = getOrCreateContextDIE(resolve(DT->getScope()));
1553 assert(dwarf::isType(ContextDIE->getTag()) &&
1554 "Static member should belong to a type.");
1556 if (DIE *StaticMemberDIE = getDIE(DT))
1557 return StaticMemberDIE;
1559 DIE &StaticMemberDIE = createAndAddDIE(DT->getTag(), *ContextDIE, DT);
1561 DIType Ty = resolve(DT->getBaseType());
1563 addString(StaticMemberDIE, dwarf::DW_AT_name, DT->getName());
1564 addType(StaticMemberDIE, Ty);
1565 addSourceLine(StaticMemberDIE, DT);
1566 addFlag(StaticMemberDIE, dwarf::DW_AT_external);
1567 addFlag(StaticMemberDIE, dwarf::DW_AT_declaration);
1569 // FIXME: We could omit private if the parent is a class_type, and
1570 // public if the parent is something else.
1571 if (DT->isProtected())
1572 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1573 dwarf::DW_ACCESS_protected);
1574 else if (DT->isPrivate())
1575 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1576 dwarf::DW_ACCESS_private);
1577 else if (DT->isPublic())
1578 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1579 dwarf::DW_ACCESS_public);
1581 if (const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(DT->getConstant()))
1582 addConstantValue(StaticMemberDIE, CI, Ty);
1583 if (const ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(DT->getConstant()))
1584 addConstantFPValue(StaticMemberDIE, CFP);
1586 return &StaticMemberDIE;
1589 void DwarfUnit::emitHeader(bool UseOffsets) {
1590 // Emit size of content not including length itself
1591 Asm->OutStreamer.AddComment("Length of Unit");
1592 Asm->EmitInt32(getHeaderSize() + UnitDie.getSize());
1594 Asm->OutStreamer.AddComment("DWARF version number");
1595 Asm->EmitInt16(DD->getDwarfVersion());
1596 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section");
1598 // We share one abbreviations table across all units so it's always at the
1599 // start of the section. Use a relocatable offset where needed to ensure
1600 // linking doesn't invalidate that offset.
1601 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1603 Asm->emitSectionOffset(TLOF.getDwarfAbbrevSection()->getBeginSymbol());
1607 Asm->OutStreamer.AddComment("Address Size (in bytes)");
1608 Asm->EmitInt8(Asm->getDataLayout().getPointerSize());
1611 void DwarfUnit::initSection(const MCSection *Section) {
1612 assert(!this->Section);
1613 this->Section = Section;
1616 void DwarfTypeUnit::emitHeader(bool UseOffsets) {
1617 DwarfUnit::emitHeader(UseOffsets);
1618 Asm->OutStreamer.AddComment("Type Signature");
1619 Asm->OutStreamer.EmitIntValue(TypeSignature, sizeof(TypeSignature));
1620 Asm->OutStreamer.AddComment("Type DIE Offset");
1621 // In a skeleton type unit there is no type DIE so emit a zero offset.
1622 Asm->OutStreamer.EmitIntValue(Ty ? Ty->getOffset() : 0,
1623 sizeof(Ty->getOffset()));
1626 bool DwarfTypeUnit::isDwoUnit() const {
1627 // Since there are no skeleton type units, all type units are dwo type units
1628 // when split DWARF is being used.
1629 return DD->useSplitDwarf();