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 "AddressPool.h"
16 #include "DwarfCompileUnit.h"
17 #include "DwarfDebug.h"
18 #include "DwarfExpression.h"
19 #include "llvm/ADT/APFloat.h"
20 #include "llvm/ADT/APInt.h"
21 #include "llvm/ADT/iterator_range.h"
22 #include "llvm/ADT/None.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineOperand.h"
25 #include "llvm/IR/Constants.h"
26 #include "llvm/IR/DataLayout.h"
27 #include "llvm/IR/GlobalValue.h"
28 #include "llvm/IR/Metadata.h"
29 #include "llvm/MC/MachineLocation.h"
30 #include "llvm/MC/MCAsmInfo.h"
31 #include "llvm/MC/MCDwarf.h"
32 #include "llvm/MC/MCSection.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/Support/Casting.h"
35 #include "llvm/Support/CommandLine.h"
36 #include "llvm/Target/TargetLoweringObjectFile.h"
37 #include "llvm/Target/TargetRegisterInfo.h"
38 #include "llvm/Target/TargetSubtargetInfo.h"
46 #define DEBUG_TYPE "dwarfdebug"
49 GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
50 cl::desc("Generate DWARF4 type units."),
53 DIEDwarfExpression::DIEDwarfExpression(const AsmPrinter &AP, DwarfUnit &DU,
55 : DwarfExpression(AP.getDwarfVersion()), AP(AP), DU(DU),
58 void DIEDwarfExpression::emitOp(uint8_t Op, const char* Comment) {
59 DU.addUInt(DIE, dwarf::DW_FORM_data1, Op);
62 void DIEDwarfExpression::emitSigned(int64_t Value) {
63 DU.addSInt(DIE, dwarf::DW_FORM_sdata, Value);
66 void DIEDwarfExpression::emitUnsigned(uint64_t Value) {
67 DU.addUInt(DIE, dwarf::DW_FORM_udata, Value);
70 bool DIEDwarfExpression::isFrameRegister(const TargetRegisterInfo &TRI,
71 unsigned MachineReg) {
72 return MachineReg == TRI.getFrameRegister(*AP.MF);
75 DwarfUnit::DwarfUnit(dwarf::Tag UnitTag, const DICompileUnit *Node,
76 AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU)
77 : DIEUnit(A->getDwarfVersion(), A->MAI->getCodePointerSize(), UnitTag),
78 CUNode(Node), Asm(A), DD(DW), DU(DWU), IndexTyDie(nullptr) {
81 DwarfTypeUnit::DwarfTypeUnit(DwarfCompileUnit &CU, AsmPrinter *A,
82 DwarfDebug *DW, DwarfFile *DWU,
83 MCDwarfDwoLineTable *SplitLineTable)
84 : DwarfUnit(dwarf::DW_TAG_type_unit, CU.getCUNode(), A, DW, DWU), CU(CU),
85 SplitLineTable(SplitLineTable) {
87 addSectionOffset(getUnitDie(), dwarf::DW_AT_stmt_list, 0);
90 DwarfUnit::~DwarfUnit() {
91 for (unsigned j = 0, M = DIEBlocks.size(); j < M; ++j)
92 DIEBlocks[j]->~DIEBlock();
93 for (unsigned j = 0, M = DIELocs.size(); j < M; ++j)
94 DIELocs[j]->~DIELoc();
97 int64_t DwarfUnit::getDefaultLowerBound() const {
98 switch (getLanguage()) {
102 // The languages below have valid values in all DWARF versions.
103 case dwarf::DW_LANG_C:
104 case dwarf::DW_LANG_C89:
105 case dwarf::DW_LANG_C_plus_plus:
108 case dwarf::DW_LANG_Fortran77:
109 case dwarf::DW_LANG_Fortran90:
112 // The languages below have valid values only if the DWARF version >= 3.
113 case dwarf::DW_LANG_C99:
114 case dwarf::DW_LANG_ObjC:
115 case dwarf::DW_LANG_ObjC_plus_plus:
116 if (DD->getDwarfVersion() >= 3)
120 case dwarf::DW_LANG_Fortran95:
121 if (DD->getDwarfVersion() >= 3)
125 // Starting with DWARF v4, all defined languages have valid values.
126 case dwarf::DW_LANG_D:
127 case dwarf::DW_LANG_Java:
128 case dwarf::DW_LANG_Python:
129 case dwarf::DW_LANG_UPC:
130 if (DD->getDwarfVersion() >= 4)
134 case dwarf::DW_LANG_Ada83:
135 case dwarf::DW_LANG_Ada95:
136 case dwarf::DW_LANG_Cobol74:
137 case dwarf::DW_LANG_Cobol85:
138 case dwarf::DW_LANG_Modula2:
139 case dwarf::DW_LANG_Pascal83:
140 case dwarf::DW_LANG_PLI:
141 if (DD->getDwarfVersion() >= 4)
145 // The languages below are new in DWARF v5.
146 case dwarf::DW_LANG_BLISS:
147 case dwarf::DW_LANG_C11:
148 case dwarf::DW_LANG_C_plus_plus_03:
149 case dwarf::DW_LANG_C_plus_plus_11:
150 case dwarf::DW_LANG_C_plus_plus_14:
151 case dwarf::DW_LANG_Dylan:
152 case dwarf::DW_LANG_Go:
153 case dwarf::DW_LANG_Haskell:
154 case dwarf::DW_LANG_OCaml:
155 case dwarf::DW_LANG_OpenCL:
156 case dwarf::DW_LANG_RenderScript:
157 case dwarf::DW_LANG_Rust:
158 case dwarf::DW_LANG_Swift:
159 if (DD->getDwarfVersion() >= 5)
163 case dwarf::DW_LANG_Fortran03:
164 case dwarf::DW_LANG_Fortran08:
165 case dwarf::DW_LANG_Julia:
166 case dwarf::DW_LANG_Modula3:
167 if (DD->getDwarfVersion() >= 5)
175 /// Check whether the DIE for this MDNode can be shared across CUs.
176 static bool isShareableAcrossCUs(const DINode *D) {
177 // When the MDNode can be part of the type system, the DIE can be shared
179 // Combining type units and cross-CU DIE sharing is lower value (since
180 // cross-CU DIE sharing is used in LTO and removes type redundancy at that
181 // level already) but may be implementable for some value in projects
182 // building multiple independent libraries with LTO and then linking those
184 return (isa<DIType>(D) ||
185 (isa<DISubprogram>(D) && !cast<DISubprogram>(D)->isDefinition())) &&
186 !GenerateDwarfTypeUnits;
189 DIE *DwarfUnit::getDIE(const DINode *D) const {
190 if (isShareableAcrossCUs(D))
191 return DU->getDIE(D);
192 return MDNodeToDieMap.lookup(D);
195 void DwarfUnit::insertDIE(const DINode *Desc, DIE *D) {
196 if (isShareableAcrossCUs(Desc)) {
197 DU->insertDIE(Desc, D);
200 MDNodeToDieMap.insert(std::make_pair(Desc, D));
203 void DwarfUnit::addFlag(DIE &Die, dwarf::Attribute Attribute) {
204 if (DD->getDwarfVersion() >= 4)
205 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_flag_present,
208 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_flag,
212 void DwarfUnit::addUInt(DIEValueList &Die, dwarf::Attribute Attribute,
213 Optional<dwarf::Form> Form, uint64_t Integer) {
215 Form = DIEInteger::BestForm(false, Integer);
216 assert(Form != dwarf::DW_FORM_implicit_const &&
217 "DW_FORM_implicit_const is used only for signed integers");
218 Die.addValue(DIEValueAllocator, Attribute, *Form, DIEInteger(Integer));
221 void DwarfUnit::addUInt(DIEValueList &Block, dwarf::Form Form,
223 addUInt(Block, (dwarf::Attribute)0, Form, Integer);
226 void DwarfUnit::addSInt(DIEValueList &Die, dwarf::Attribute Attribute,
227 Optional<dwarf::Form> Form, int64_t Integer) {
229 Form = DIEInteger::BestForm(true, Integer);
230 Die.addValue(DIEValueAllocator, Attribute, *Form, DIEInteger(Integer));
233 void DwarfUnit::addSInt(DIELoc &Die, Optional<dwarf::Form> Form,
235 addSInt(Die, (dwarf::Attribute)0, Form, Integer);
238 void DwarfUnit::addString(DIE &Die, dwarf::Attribute Attribute,
240 Die.addValue(DIEValueAllocator, Attribute,
241 isDwoUnit() ? dwarf::DW_FORM_GNU_str_index : dwarf::DW_FORM_strp,
242 DIEString(DU->getStringPool().getEntry(*Asm, String)));
245 DIEValueList::value_iterator DwarfUnit::addLabel(DIEValueList &Die,
246 dwarf::Attribute Attribute,
248 const MCSymbol *Label) {
249 return Die.addValue(DIEValueAllocator, Attribute, Form, DIELabel(Label));
252 void DwarfUnit::addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label) {
253 addLabel(Die, (dwarf::Attribute)0, Form, Label);
256 void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
258 if (DD->getDwarfVersion() >= 4)
259 addUInt(Die, Attribute, dwarf::DW_FORM_sec_offset, Integer);
261 addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
264 unsigned DwarfTypeUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
265 return SplitLineTable ? SplitLineTable->getFile(DirName, FileName)
266 : getCU().getOrCreateSourceID(FileName, DirName);
269 void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) {
270 if (!DD->useSplitDwarf()) {
271 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
272 addLabel(Die, dwarf::DW_FORM_udata, Sym);
274 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_addr_index);
275 addUInt(Die, dwarf::DW_FORM_GNU_addr_index,
276 DD->getAddressPool().getIndex(Sym));
280 void DwarfUnit::addLabelDelta(DIE &Die, dwarf::Attribute Attribute,
281 const MCSymbol *Hi, const MCSymbol *Lo) {
282 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_data4,
283 new (DIEValueAllocator) DIEDelta(Hi, Lo));
286 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry) {
287 addDIEEntry(Die, Attribute, DIEEntry(Entry));
290 void DwarfUnit::addDIETypeSignature(DIE &Die, uint64_t Signature) {
291 // Flag the type unit reference as a declaration so that if it contains
292 // members (implicit special members, static data member definitions, member
293 // declarations for definitions in this CU, etc) consumers don't get confused
294 // and think this is a full definition.
295 addFlag(Die, dwarf::DW_AT_declaration);
297 Die.addValue(DIEValueAllocator, dwarf::DW_AT_signature,
298 dwarf::DW_FORM_ref_sig8, DIEInteger(Signature));
301 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
303 const DIEUnit *CU = Die.getUnit();
304 const DIEUnit *EntryCU = Entry.getEntry().getUnit();
306 // We assume that Die belongs to this CU, if it is not linked to any CU yet.
307 CU = getUnitDie().getUnit();
309 EntryCU = getUnitDie().getUnit();
310 Die.addValue(DIEValueAllocator, Attribute,
311 EntryCU == CU ? dwarf::DW_FORM_ref4 : dwarf::DW_FORM_ref_addr,
315 DIE &DwarfUnit::createAndAddDIE(unsigned Tag, DIE &Parent, const DINode *N) {
316 DIE &Die = Parent.addChild(DIE::get(DIEValueAllocator, (dwarf::Tag)Tag));
322 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Loc) {
323 Loc->ComputeSize(Asm);
324 DIELocs.push_back(Loc); // Memoize so we can call the destructor later on.
325 Die.addValue(DIEValueAllocator, Attribute,
326 Loc->BestForm(DD->getDwarfVersion()), Loc);
329 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute,
331 Block->ComputeSize(Asm);
332 DIEBlocks.push_back(Block); // Memoize so we can call the destructor later on.
333 Die.addValue(DIEValueAllocator, Attribute, Block->BestForm(), Block);
336 void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, StringRef File,
337 StringRef Directory) {
341 unsigned FileID = getOrCreateSourceID(File, Directory);
342 assert(FileID && "Invalid file id");
343 addUInt(Die, dwarf::DW_AT_decl_file, None, FileID);
344 addUInt(Die, dwarf::DW_AT_decl_line, None, Line);
347 void DwarfUnit::addSourceLine(DIE &Die, const DILocalVariable *V) {
350 addSourceLine(Die, V->getLine(), V->getScope()->getFilename(),
351 V->getScope()->getDirectory());
354 void DwarfUnit::addSourceLine(DIE &Die, const DIGlobalVariable *G) {
357 addSourceLine(Die, G->getLine(), G->getFilename(), G->getDirectory());
360 void DwarfUnit::addSourceLine(DIE &Die, const DISubprogram *SP) {
363 addSourceLine(Die, SP->getLine(), SP->getFilename(), SP->getDirectory());
366 void DwarfUnit::addSourceLine(DIE &Die, const DIType *Ty) {
369 addSourceLine(Die, Ty->getLine(), Ty->getFilename(), Ty->getDirectory());
372 void DwarfUnit::addSourceLine(DIE &Die, const DIObjCProperty *Ty) {
375 addSourceLine(Die, Ty->getLine(), Ty->getFilename(), Ty->getDirectory());
378 void DwarfUnit::addSourceLine(DIE &Die, const DINamespace *NS) {
379 addSourceLine(Die, NS->getLine(), NS->getFilename(), NS->getDirectory());
382 /* Byref variables, in Blocks, are declared by the programmer as "SomeType
383 VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
384 gives the variable VarName either the struct, or a pointer to the struct, as
385 its type. This is necessary for various behind-the-scenes things the
386 compiler needs to do with by-reference variables in Blocks.
388 However, as far as the original *programmer* is concerned, the variable
389 should still have type 'SomeType', as originally declared.
391 The function getBlockByrefType dives into the __Block_byref_x_VarName
392 struct to find the original type of the variable, which is then assigned to
393 the variable's Debug Information Entry as its real type. So far, so good.
394 However now the debugger will expect the variable VarName to have the type
395 SomeType. So we need the location attribute for the variable to be an
396 expression that explains to the debugger how to navigate through the
397 pointers and struct to find the actual variable of type SomeType.
399 The following function does just that. We start by getting
400 the "normal" location for the variable. This will be the location
401 of either the struct __Block_byref_x_VarName or the pointer to the
402 struct __Block_byref_x_VarName.
404 The struct will look something like:
406 struct __Block_byref_x_VarName {
408 struct __Block_byref_x_VarName *forwarding;
409 ... <various other fields>
411 ... <maybe more fields>
414 If we are given the struct directly (as our starting point) we
415 need to tell the debugger to:
417 1). Add the offset of the forwarding field.
419 2). Follow that pointer to get the real __Block_byref_x_VarName
420 struct to use (the real one may have been copied onto the heap).
422 3). Add the offset for the field VarName, to find the actual variable.
424 If we started with a pointer to the struct, then we need to
425 dereference that pointer first, before the other steps.
426 Translating this into DWARF ops, we will need to append the following
427 to the current location description for the variable:
429 DW_OP_deref -- optional, if we start with a pointer
430 DW_OP_plus_uconst <forward_fld_offset>
432 DW_OP_plus_uconst <varName_fld_offset>
434 That is what this function does. */
436 void DwarfUnit::addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
437 dwarf::Attribute Attribute,
438 const MachineLocation &Location) {
439 const DIType *Ty = DV.getType();
440 const DIType *TmpTy = Ty;
441 uint16_t Tag = Ty->getTag();
442 bool isPointer = false;
444 StringRef varName = DV.getName();
446 if (Tag == dwarf::DW_TAG_pointer_type) {
447 auto *DTy = cast<DIDerivedType>(Ty);
448 TmpTy = resolve(DTy->getBaseType());
452 // Find the __forwarding field and the variable field in the __Block_byref
454 DINodeArray Fields = cast<DICompositeType>(TmpTy)->getElements();
455 const DIDerivedType *varField = nullptr;
456 const DIDerivedType *forwardingField = nullptr;
458 for (unsigned i = 0, N = Fields.size(); i < N; ++i) {
459 auto *DT = cast<DIDerivedType>(Fields[i]);
460 StringRef fieldName = DT->getName();
461 if (fieldName == "__forwarding")
462 forwardingField = DT;
463 else if (fieldName == varName)
467 // Get the offsets for the forwarding field and the variable field.
468 unsigned forwardingFieldOffset = forwardingField->getOffsetInBits() >> 3;
469 unsigned varFieldOffset = varField->getOffsetInBits() >> 2;
471 // Decode the original location, and use that as the start of the byref
472 // variable's location.
473 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
474 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
475 if (Location.isIndirect())
476 DwarfExpr.setMemoryLocationKind();
478 SmallVector<uint64_t, 9> Ops;
479 if (Location.isIndirect() && Location.getOffset()) {
480 Ops.push_back(dwarf::DW_OP_plus);
481 Ops.push_back(Location.getOffset());
483 // If we started with a pointer to the __Block_byref... struct, then
484 // the first thing we need to do is dereference the pointer (DW_OP_deref).
486 Ops.push_back(dwarf::DW_OP_deref);
488 // Next add the offset for the '__forwarding' field:
489 // DW_OP_plus_uconst ForwardingFieldOffset. Note there's no point in
490 // adding the offset if it's 0.
491 if (forwardingFieldOffset > 0) {
492 Ops.push_back(dwarf::DW_OP_plus);
493 Ops.push_back(forwardingFieldOffset);
496 // Now dereference the __forwarding field to get to the real __Block_byref
497 // struct: DW_OP_deref.
498 Ops.push_back(dwarf::DW_OP_deref);
500 // Now that we've got the real __Block_byref... struct, add the offset
501 // for the variable's field to get to the location of the actual variable:
502 // DW_OP_plus_uconst varFieldOffset. Again, don't add if it's 0.
503 if (varFieldOffset > 0) {
504 Ops.push_back(dwarf::DW_OP_plus);
505 Ops.push_back(varFieldOffset);
508 DIExpressionCursor Cursor(Ops);
509 const TargetRegisterInfo &TRI = *Asm->MF->getSubtarget().getRegisterInfo();
510 if (!DwarfExpr.addMachineRegExpression(TRI, Cursor, Location.getReg()))
512 DwarfExpr.addExpression(std::move(Cursor));
514 // Now attach the location information to the DIE.
515 addBlock(Die, Attribute, DwarfExpr.finalize());
518 /// Return true if type encoding is unsigned.
519 static bool isUnsignedDIType(DwarfDebug *DD, const DIType *Ty) {
520 if (auto *CTy = dyn_cast<DICompositeType>(Ty)) {
521 // FIXME: Enums without a fixed underlying type have unknown signedness
522 // here, leading to incorrectly emitted constants.
523 if (CTy->getTag() == dwarf::DW_TAG_enumeration_type)
526 // (Pieces of) aggregate types that get hacked apart by SROA may be
527 // represented by a constant. Encode them as unsigned bytes.
531 if (auto *DTy = dyn_cast<DIDerivedType>(Ty)) {
532 dwarf::Tag T = (dwarf::Tag)Ty->getTag();
533 // Encode pointer constants as unsigned bytes. This is used at least for
534 // null pointer constant emission.
535 // FIXME: reference and rvalue_reference /probably/ shouldn't be allowed
536 // here, but accept them for now due to a bug in SROA producing bogus
538 if (T == dwarf::DW_TAG_pointer_type ||
539 T == dwarf::DW_TAG_ptr_to_member_type ||
540 T == dwarf::DW_TAG_reference_type ||
541 T == dwarf::DW_TAG_rvalue_reference_type)
543 assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
544 T == dwarf::DW_TAG_volatile_type ||
545 T == dwarf::DW_TAG_restrict_type || T == dwarf::DW_TAG_atomic_type);
546 DITypeRef Deriv = DTy->getBaseType();
547 assert(Deriv && "Expected valid base type");
548 return isUnsignedDIType(DD, DD->resolve(Deriv));
551 auto *BTy = cast<DIBasicType>(Ty);
552 unsigned Encoding = BTy->getEncoding();
553 assert((Encoding == dwarf::DW_ATE_unsigned ||
554 Encoding == dwarf::DW_ATE_unsigned_char ||
555 Encoding == dwarf::DW_ATE_signed ||
556 Encoding == dwarf::DW_ATE_signed_char ||
557 Encoding == dwarf::DW_ATE_float || Encoding == dwarf::DW_ATE_UTF ||
558 Encoding == dwarf::DW_ATE_boolean ||
559 (Ty->getTag() == dwarf::DW_TAG_unspecified_type &&
560 Ty->getName() == "decltype(nullptr)")) &&
561 "Unsupported encoding");
562 return Encoding == dwarf::DW_ATE_unsigned ||
563 Encoding == dwarf::DW_ATE_unsigned_char ||
564 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean ||
565 Ty->getTag() == dwarf::DW_TAG_unspecified_type;
568 void DwarfUnit::addConstantFPValue(DIE &Die, const MachineOperand &MO) {
569 assert(MO.isFPImm() && "Invalid machine operand!");
570 DIEBlock *Block = new (DIEValueAllocator) DIEBlock;
571 APFloat FPImm = MO.getFPImm()->getValueAPF();
573 // Get the raw data form of the floating point.
574 const APInt FltVal = FPImm.bitcastToAPInt();
575 const char *FltPtr = (const char *)FltVal.getRawData();
577 int NumBytes = FltVal.getBitWidth() / 8; // 8 bits per byte.
578 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
579 int Incr = (LittleEndian ? 1 : -1);
580 int Start = (LittleEndian ? 0 : NumBytes - 1);
581 int Stop = (LittleEndian ? NumBytes : -1);
583 // Output the constant to DWARF one byte at a time.
584 for (; Start != Stop; Start += Incr)
585 addUInt(*Block, dwarf::DW_FORM_data1, (unsigned char)0xFF & FltPtr[Start]);
587 addBlock(Die, dwarf::DW_AT_const_value, Block);
590 void DwarfUnit::addConstantFPValue(DIE &Die, const ConstantFP *CFP) {
591 // Pass this down to addConstantValue as an unsigned bag of bits.
592 addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
595 void DwarfUnit::addConstantValue(DIE &Die, const ConstantInt *CI,
597 addConstantValue(Die, CI->getValue(), Ty);
600 void DwarfUnit::addConstantValue(DIE &Die, const MachineOperand &MO,
602 assert(MO.isImm() && "Invalid machine operand!");
604 addConstantValue(Die, isUnsignedDIType(DD, Ty), MO.getImm());
607 void DwarfUnit::addConstantValue(DIE &Die, bool Unsigned, uint64_t Val) {
608 // FIXME: This is a bit conservative/simple - it emits negative values always
609 // sign extended to 64 bits rather than minimizing the number of bytes.
610 addUInt(Die, dwarf::DW_AT_const_value,
611 Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata, Val);
614 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, const DIType *Ty) {
615 addConstantValue(Die, Val, isUnsignedDIType(DD, Ty));
618 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
619 unsigned CIBitWidth = Val.getBitWidth();
620 if (CIBitWidth <= 64) {
621 addConstantValue(Die, Unsigned,
622 Unsigned ? Val.getZExtValue() : Val.getSExtValue());
626 DIEBlock *Block = new (DIEValueAllocator) DIEBlock;
628 // Get the raw data form of the large APInt.
629 const uint64_t *Ptr64 = Val.getRawData();
631 int NumBytes = Val.getBitWidth() / 8; // 8 bits per byte.
632 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
634 // Output the constant to DWARF one byte at a time.
635 for (int i = 0; i < NumBytes; i++) {
638 c = Ptr64[i / 8] >> (8 * (i & 7));
640 c = Ptr64[(NumBytes - 1 - i) / 8] >> (8 * ((NumBytes - 1 - i) & 7));
641 addUInt(*Block, dwarf::DW_FORM_data1, c);
644 addBlock(Die, dwarf::DW_AT_const_value, Block);
647 void DwarfUnit::addLinkageName(DIE &Die, StringRef LinkageName) {
648 if (!LinkageName.empty())
650 DD->getDwarfVersion() >= 4 ? dwarf::DW_AT_linkage_name
651 : dwarf::DW_AT_MIPS_linkage_name,
652 GlobalValue::getRealLinkageName(LinkageName));
655 void DwarfUnit::addTemplateParams(DIE &Buffer, DINodeArray TParams) {
656 // Add template parameters.
657 for (const auto *Element : TParams) {
658 if (auto *TTP = dyn_cast<DITemplateTypeParameter>(Element))
659 constructTemplateTypeParameterDIE(Buffer, TTP);
660 else if (auto *TVP = dyn_cast<DITemplateValueParameter>(Element))
661 constructTemplateValueParameterDIE(Buffer, TVP);
665 DIE *DwarfUnit::getOrCreateContextDIE(const DIScope *Context) {
666 if (!Context || isa<DIFile>(Context))
667 return &getUnitDie();
668 if (auto *T = dyn_cast<DIType>(Context))
669 return getOrCreateTypeDIE(T);
670 if (auto *NS = dyn_cast<DINamespace>(Context))
671 return getOrCreateNameSpace(NS);
672 if (auto *SP = dyn_cast<DISubprogram>(Context))
673 return getOrCreateSubprogramDIE(SP);
674 if (auto *M = dyn_cast<DIModule>(Context))
675 return getOrCreateModule(M);
676 return getDIE(Context);
679 DIE *DwarfTypeUnit::createTypeDIE(const DICompositeType *Ty) {
680 auto *Context = resolve(Ty->getScope());
681 DIE *ContextDIE = getOrCreateContextDIE(Context);
683 if (DIE *TyDIE = getDIE(Ty))
687 DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
689 constructTypeDIE(TyDIE, cast<DICompositeType>(Ty));
691 updateAcceleratorTables(Context, Ty, TyDIE);
695 DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
699 auto *Ty = cast<DIType>(TyNode);
701 // DW_TAG_restrict_type is not supported in DWARF2
702 if (Ty->getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
703 return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()));
705 // DW_TAG_atomic_type is not supported in DWARF < 5
706 if (Ty->getTag() == dwarf::DW_TAG_atomic_type && DD->getDwarfVersion() < 5)
707 return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()));
709 // Construct the context before querying for the existence of the DIE in case
710 // such construction creates the DIE.
711 auto *Context = resolve(Ty->getScope());
712 DIE *ContextDIE = getOrCreateContextDIE(Context);
715 if (DIE *TyDIE = getDIE(Ty))
719 DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
721 updateAcceleratorTables(Context, Ty, TyDIE);
723 if (auto *BT = dyn_cast<DIBasicType>(Ty))
724 constructTypeDIE(TyDIE, BT);
725 else if (auto *STy = dyn_cast<DISubroutineType>(Ty))
726 constructTypeDIE(TyDIE, STy);
727 else if (auto *CTy = dyn_cast<DICompositeType>(Ty)) {
728 if (GenerateDwarfTypeUnits && !Ty->isForwardDecl())
729 if (MDString *TypeId = CTy->getRawIdentifier()) {
730 DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);
731 // Skip updating the accelerator tables since this is not the full type.
734 constructTypeDIE(TyDIE, CTy);
736 constructTypeDIE(TyDIE, cast<DIDerivedType>(Ty));
742 void DwarfUnit::updateAcceleratorTables(const DIScope *Context,
743 const DIType *Ty, const DIE &TyDIE) {
744 if (!Ty->getName().empty() && !Ty->isForwardDecl()) {
745 bool IsImplementation = false;
746 if (auto *CT = dyn_cast<DICompositeType>(Ty)) {
747 // A runtime language of 0 actually means C/C++ and that any
748 // non-negative value is some version of Objective-C/C++.
749 IsImplementation = CT->getRuntimeLang() == 0 || CT->isObjcClassComplete();
751 unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
752 DD->addAccelType(Ty->getName(), TyDIE, Flags);
754 if (!Context || isa<DICompileUnit>(Context) || isa<DIFile>(Context) ||
755 isa<DINamespace>(Context))
756 addGlobalType(Ty, TyDIE, Context);
760 void DwarfUnit::addType(DIE &Entity, const DIType *Ty,
761 dwarf::Attribute Attribute) {
762 assert(Ty && "Trying to add a type that doesn't exist?");
763 addDIEEntry(Entity, Attribute, DIEEntry(*getOrCreateTypeDIE(Ty)));
766 std::string DwarfUnit::getParentContextString(const DIScope *Context) const {
770 // FIXME: Decide whether to implement this for non-C++ languages.
771 if (getLanguage() != dwarf::DW_LANG_C_plus_plus)
775 SmallVector<const DIScope *, 1> Parents;
776 while (!isa<DICompileUnit>(Context)) {
777 Parents.push_back(Context);
778 if (Context->getScope())
779 Context = resolve(Context->getScope());
781 // Structure, etc types will have a NULL context if they're at the top
786 // Reverse iterate over our list to go from the outermost construct to the
788 for (const DIScope *Ctx : make_range(Parents.rbegin(), Parents.rend())) {
789 StringRef Name = Ctx->getName();
790 if (Name.empty() && isa<DINamespace>(Ctx))
791 Name = "(anonymous namespace)";
800 void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIBasicType *BTy) {
801 // Get core information.
802 StringRef Name = BTy->getName();
803 // Add name if not anonymous or intermediate type.
805 addString(Buffer, dwarf::DW_AT_name, Name);
807 // An unspecified type only has a name attribute.
808 if (BTy->getTag() == dwarf::DW_TAG_unspecified_type)
811 addUInt(Buffer, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
814 uint64_t Size = BTy->getSizeInBits() >> 3;
815 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
818 void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy) {
819 // Get core information.
820 StringRef Name = DTy->getName();
821 uint64_t Size = DTy->getSizeInBits() >> 3;
822 uint16_t Tag = Buffer.getTag();
824 // Map to main type, void will not have a type.
825 const DIType *FromTy = resolve(DTy->getBaseType());
827 addType(Buffer, FromTy);
829 // Add name if not anonymous or intermediate type.
831 addString(Buffer, dwarf::DW_AT_name, Name);
833 // Add size if non-zero (derived types might be zero-sized.)
834 if (Size && Tag != dwarf::DW_TAG_pointer_type
835 && Tag != dwarf::DW_TAG_ptr_to_member_type
836 && Tag != dwarf::DW_TAG_reference_type
837 && Tag != dwarf::DW_TAG_rvalue_reference_type)
838 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
840 if (Tag == dwarf::DW_TAG_ptr_to_member_type)
842 Buffer, dwarf::DW_AT_containing_type,
843 *getOrCreateTypeDIE(resolve(cast<DIDerivedType>(DTy)->getClassType())));
844 // Add source line info if available and TyDesc is not a forward declaration.
845 if (!DTy->isForwardDecl())
846 addSourceLine(Buffer, DTy);
848 // If DWARF address space value is other than None, add it for pointer and
849 // reference types as DW_AT_address_class.
850 if (DTy->getDWARFAddressSpace() && (Tag == dwarf::DW_TAG_pointer_type ||
851 Tag == dwarf::DW_TAG_reference_type))
852 addUInt(Buffer, dwarf::DW_AT_address_class, dwarf::DW_FORM_data4,
853 DTy->getDWARFAddressSpace().getValue());
856 void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DITypeRefArray Args) {
857 for (unsigned i = 1, N = Args.size(); i < N; ++i) {
858 const DIType *Ty = resolve(Args[i]);
860 assert(i == N-1 && "Unspecified parameter must be the last argument");
861 createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
863 DIE &Arg = createAndAddDIE(dwarf::DW_TAG_formal_parameter, Buffer);
865 if (Ty->isArtificial())
866 addFlag(Arg, dwarf::DW_AT_artificial);
871 void DwarfUnit::constructTypeDIE(DIE &Buffer, const DISubroutineType *CTy) {
872 // Add return type. A void return won't have a type.
873 auto Elements = cast<DISubroutineType>(CTy)->getTypeArray();
875 if (auto RTy = resolve(Elements[0]))
876 addType(Buffer, RTy);
878 bool isPrototyped = true;
879 if (Elements.size() == 2 && !Elements[1])
880 isPrototyped = false;
882 constructSubprogramArguments(Buffer, Elements);
884 // Add prototype flag if we're dealing with a C language and the function has
886 uint16_t Language = getLanguage();
888 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
889 Language == dwarf::DW_LANG_ObjC))
890 addFlag(Buffer, dwarf::DW_AT_prototyped);
892 // Add a DW_AT_calling_convention if this has an explicit convention.
893 if (CTy->getCC() && CTy->getCC() != dwarf::DW_CC_normal)
894 addUInt(Buffer, dwarf::DW_AT_calling_convention, dwarf::DW_FORM_data1,
897 if (CTy->isLValueReference())
898 addFlag(Buffer, dwarf::DW_AT_reference);
900 if (CTy->isRValueReference())
901 addFlag(Buffer, dwarf::DW_AT_rvalue_reference);
904 void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
905 // Add name if not anonymous or intermediate type.
906 StringRef Name = CTy->getName();
908 uint64_t Size = CTy->getSizeInBits() >> 3;
909 uint16_t Tag = Buffer.getTag();
912 case dwarf::DW_TAG_array_type:
913 constructArrayTypeDIE(Buffer, CTy);
915 case dwarf::DW_TAG_enumeration_type:
916 constructEnumTypeDIE(Buffer, CTy);
918 case dwarf::DW_TAG_structure_type:
919 case dwarf::DW_TAG_union_type:
920 case dwarf::DW_TAG_class_type: {
921 // Add elements to structure type.
922 DINodeArray Elements = CTy->getElements();
923 for (const auto *Element : Elements) {
926 if (auto *SP = dyn_cast<DISubprogram>(Element))
927 getOrCreateSubprogramDIE(SP);
928 else if (auto *DDTy = dyn_cast<DIDerivedType>(Element)) {
929 if (DDTy->getTag() == dwarf::DW_TAG_friend) {
930 DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
931 addType(ElemDie, resolve(DDTy->getBaseType()), dwarf::DW_AT_friend);
932 } else if (DDTy->isStaticMember()) {
933 getOrCreateStaticMemberDIE(DDTy);
935 constructMemberDIE(Buffer, DDTy);
937 } else if (auto *Property = dyn_cast<DIObjCProperty>(Element)) {
938 DIE &ElemDie = createAndAddDIE(Property->getTag(), Buffer);
939 StringRef PropertyName = Property->getName();
940 addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
941 if (Property->getType())
942 addType(ElemDie, resolve(Property->getType()));
943 addSourceLine(ElemDie, Property);
944 StringRef GetterName = Property->getGetterName();
945 if (!GetterName.empty())
946 addString(ElemDie, dwarf::DW_AT_APPLE_property_getter, GetterName);
947 StringRef SetterName = Property->getSetterName();
948 if (!SetterName.empty())
949 addString(ElemDie, dwarf::DW_AT_APPLE_property_setter, SetterName);
950 if (unsigned PropertyAttributes = Property->getAttributes())
951 addUInt(ElemDie, dwarf::DW_AT_APPLE_property_attribute, None,
956 if (CTy->isAppleBlockExtension())
957 addFlag(Buffer, dwarf::DW_AT_APPLE_block);
959 // This is outside the DWARF spec, but GDB expects a DW_AT_containing_type
960 // inside C++ composite types to point to the base class with the vtable.
961 if (auto *ContainingType =
962 dyn_cast_or_null<DICompositeType>(resolve(CTy->getVTableHolder())))
963 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
964 *getOrCreateTypeDIE(ContainingType));
966 if (CTy->isObjcClassComplete())
967 addFlag(Buffer, dwarf::DW_AT_APPLE_objc_complete_type);
969 // Add template parameters to a class, structure or union types.
970 // FIXME: The support isn't in the metadata for this yet.
971 if (Tag == dwarf::DW_TAG_class_type ||
972 Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
973 addTemplateParams(Buffer, CTy->getTemplateParams());
981 // Add name if not anonymous or intermediate type.
983 addString(Buffer, dwarf::DW_AT_name, Name);
985 if (Tag == dwarf::DW_TAG_enumeration_type ||
986 Tag == dwarf::DW_TAG_class_type || Tag == dwarf::DW_TAG_structure_type ||
987 Tag == dwarf::DW_TAG_union_type) {
988 // Add size if non-zero (derived types might be zero-sized.)
989 // TODO: Do we care about size for enum forward declarations?
991 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
992 else if (!CTy->isForwardDecl())
993 // Add zero size if it is not a forward declaration.
994 addUInt(Buffer, dwarf::DW_AT_byte_size, None, 0);
996 // If we're a forward decl, say so.
997 if (CTy->isForwardDecl())
998 addFlag(Buffer, dwarf::DW_AT_declaration);
1000 // Add source line info if available.
1001 if (!CTy->isForwardDecl())
1002 addSourceLine(Buffer, CTy);
1004 // No harm in adding the runtime language to the declaration.
1005 unsigned RLang = CTy->getRuntimeLang();
1007 addUInt(Buffer, dwarf::DW_AT_APPLE_runtime_class, dwarf::DW_FORM_data1,
1010 // Add align info if available.
1011 if (uint32_t AlignInBytes = CTy->getAlignInBytes())
1012 addUInt(Buffer, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata,
1017 void DwarfUnit::constructTemplateTypeParameterDIE(
1018 DIE &Buffer, const DITemplateTypeParameter *TP) {
1020 createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
1021 // Add the type if it exists, it could be void and therefore no type.
1023 addType(ParamDIE, resolve(TP->getType()));
1024 if (!TP->getName().empty())
1025 addString(ParamDIE, dwarf::DW_AT_name, TP->getName());
1028 void DwarfUnit::constructTemplateValueParameterDIE(
1029 DIE &Buffer, const DITemplateValueParameter *VP) {
1030 DIE &ParamDIE = createAndAddDIE(VP->getTag(), Buffer);
1032 // Add the type if there is one, template template and template parameter
1033 // packs will not have a type.
1034 if (VP->getTag() == dwarf::DW_TAG_template_value_parameter)
1035 addType(ParamDIE, resolve(VP->getType()));
1036 if (!VP->getName().empty())
1037 addString(ParamDIE, dwarf::DW_AT_name, VP->getName());
1038 if (Metadata *Val = VP->getValue()) {
1039 if (ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(Val))
1040 addConstantValue(ParamDIE, CI, resolve(VP->getType()));
1041 else if (GlobalValue *GV = mdconst::dyn_extract<GlobalValue>(Val)) {
1042 // We cannot describe the location of dllimport'd entities: the
1043 // computation of their address requires loads from the IAT.
1044 if (!GV->hasDLLImportStorageClass()) {
1045 // For declaration non-type template parameters (such as global values
1047 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
1048 addOpAddress(*Loc, Asm->getSymbol(GV));
1049 // Emit DW_OP_stack_value to use the address as the immediate value of
1050 // the parameter, rather than a pointer to it.
1051 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_stack_value);
1052 addBlock(ParamDIE, dwarf::DW_AT_location, Loc);
1054 } else if (VP->getTag() == dwarf::DW_TAG_GNU_template_template_param) {
1055 assert(isa<MDString>(Val));
1056 addString(ParamDIE, dwarf::DW_AT_GNU_template_name,
1057 cast<MDString>(Val)->getString());
1058 } else if (VP->getTag() == dwarf::DW_TAG_GNU_template_parameter_pack) {
1059 addTemplateParams(ParamDIE, cast<MDTuple>(Val));
1064 DIE *DwarfUnit::getOrCreateNameSpace(const DINamespace *NS) {
1065 // Construct the context before querying for the existence of the DIE in case
1066 // such construction creates the DIE.
1067 DIE *ContextDIE = getOrCreateContextDIE(NS->getScope());
1069 if (DIE *NDie = getDIE(NS))
1071 DIE &NDie = createAndAddDIE(dwarf::DW_TAG_namespace, *ContextDIE, NS);
1073 StringRef Name = NS->getName();
1075 addString(NDie, dwarf::DW_AT_name, NS->getName());
1077 Name = "(anonymous namespace)";
1078 DD->addAccelNamespace(Name, NDie);
1079 addGlobalName(Name, NDie, NS->getScope());
1080 addSourceLine(NDie, NS);
1081 if (NS->getExportSymbols())
1082 addFlag(NDie, dwarf::DW_AT_export_symbols);
1086 DIE *DwarfUnit::getOrCreateModule(const DIModule *M) {
1087 // Construct the context before querying for the existence of the DIE in case
1088 // such construction creates the DIE.
1089 DIE *ContextDIE = getOrCreateContextDIE(M->getScope());
1091 if (DIE *MDie = getDIE(M))
1093 DIE &MDie = createAndAddDIE(dwarf::DW_TAG_module, *ContextDIE, M);
1095 if (!M->getName().empty()) {
1096 addString(MDie, dwarf::DW_AT_name, M->getName());
1097 addGlobalName(M->getName(), MDie, M->getScope());
1099 if (!M->getConfigurationMacros().empty())
1100 addString(MDie, dwarf::DW_AT_LLVM_config_macros,
1101 M->getConfigurationMacros());
1102 if (!M->getIncludePath().empty())
1103 addString(MDie, dwarf::DW_AT_LLVM_include_path, M->getIncludePath());
1104 if (!M->getISysRoot().empty())
1105 addString(MDie, dwarf::DW_AT_LLVM_isysroot, M->getISysRoot());
1110 DIE *DwarfUnit::getOrCreateSubprogramDIE(const DISubprogram *SP, bool Minimal) {
1111 // Construct the context before querying for the existence of the DIE in case
1112 // such construction creates the DIE (as is the case for member function
1115 Minimal ? &getUnitDie() : getOrCreateContextDIE(resolve(SP->getScope()));
1117 if (DIE *SPDie = getDIE(SP))
1120 if (auto *SPDecl = SP->getDeclaration()) {
1122 // Add subprogram definitions to the CU die directly.
1123 ContextDIE = &getUnitDie();
1124 // Build the decl now to ensure it precedes the definition.
1125 getOrCreateSubprogramDIE(SPDecl);
1129 // DW_TAG_inlined_subroutine may refer to this DIE.
1130 DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
1132 // Stop here and fill this in later, depending on whether or not this
1133 // subprogram turns out to have inlined instances or not.
1134 if (SP->isDefinition())
1137 applySubprogramAttributes(SP, SPDie);
1141 bool DwarfUnit::applySubprogramDefinitionAttributes(const DISubprogram *SP,
1143 DIE *DeclDie = nullptr;
1144 StringRef DeclLinkageName;
1145 if (auto *SPDecl = SP->getDeclaration()) {
1146 DeclDie = getDIE(SPDecl);
1147 assert(DeclDie && "This DIE should've already been constructed when the "
1148 "definition DIE was created in "
1149 "getOrCreateSubprogramDIE");
1150 // Look at the Decl's linkage name only if we emitted it.
1151 if (DD->useAllLinkageNames())
1152 DeclLinkageName = SPDecl->getLinkageName();
1154 getOrCreateSourceID(SPDecl->getFilename(), SPDecl->getDirectory());
1155 unsigned DefID = getOrCreateSourceID(SP->getFilename(), SP->getDirectory());
1156 if (DeclID != DefID)
1157 addUInt(SPDie, dwarf::DW_AT_decl_file, None, DefID);
1159 if (SP->getLine() != SPDecl->getLine())
1160 addUInt(SPDie, dwarf::DW_AT_decl_line, None, SP->getLine());
1163 // Add function template parameters.
1164 addTemplateParams(SPDie, SP->getTemplateParams());
1166 // Add the linkage name if we have one and it isn't in the Decl.
1167 StringRef LinkageName = SP->getLinkageName();
1168 assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
1169 LinkageName == DeclLinkageName) &&
1170 "decl has a linkage name and it is different");
1171 if (DeclLinkageName.empty() &&
1172 // Always emit it for abstract subprograms.
1173 (DD->useAllLinkageNames() || DU->getAbstractSPDies().lookup(SP)))
1174 addLinkageName(SPDie, LinkageName);
1179 // Refer to the function declaration where all the other attributes will be
1181 addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
1185 void DwarfUnit::applySubprogramAttributes(const DISubprogram *SP, DIE &SPDie,
1186 bool SkipSPAttributes) {
1187 // If -fdebug-info-for-profiling is enabled, need to emit the subprogram
1188 // and its source location.
1189 bool SkipSPSourceLocation = SkipSPAttributes &&
1190 !CUNode->getDebugInfoForProfiling();
1191 if (!SkipSPSourceLocation)
1192 if (applySubprogramDefinitionAttributes(SP, SPDie))
1195 // Constructors and operators for anonymous aggregates do not have names.
1196 if (!SP->getName().empty())
1197 addString(SPDie, dwarf::DW_AT_name, SP->getName());
1199 if (!SkipSPSourceLocation)
1200 addSourceLine(SPDie, SP);
1202 // Skip the rest of the attributes under -gmlt to save space.
1203 if (SkipSPAttributes)
1206 // Add the prototype if we have a prototype and we have a C like
1208 uint16_t Language = getLanguage();
1209 if (SP->isPrototyped() &&
1210 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1211 Language == dwarf::DW_LANG_ObjC))
1212 addFlag(SPDie, dwarf::DW_AT_prototyped);
1215 DITypeRefArray Args;
1216 if (const DISubroutineType *SPTy = SP->getType()) {
1217 Args = SPTy->getTypeArray();
1221 // Add a DW_AT_calling_convention if this has an explicit convention.
1222 if (CC && CC != dwarf::DW_CC_normal)
1223 addUInt(SPDie, dwarf::DW_AT_calling_convention, dwarf::DW_FORM_data1, CC);
1225 // Add a return type. If this is a type like a C/C++ void type we don't add a
1228 if (auto Ty = resolve(Args[0]))
1231 unsigned VK = SP->getVirtuality();
1233 addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1, VK);
1234 if (SP->getVirtualIndex() != -1u) {
1235 DIELoc *Block = getDIELoc();
1236 addUInt(*Block, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1237 addUInt(*Block, dwarf::DW_FORM_udata, SP->getVirtualIndex());
1238 addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
1240 ContainingTypeMap.insert(
1241 std::make_pair(&SPDie, resolve(SP->getContainingType())));
1244 if (!SP->isDefinition()) {
1245 addFlag(SPDie, dwarf::DW_AT_declaration);
1247 // Add arguments. Do not add arguments for subprogram definition. They will
1248 // be handled while processing variables.
1249 constructSubprogramArguments(SPDie, Args);
1252 if (SP->isArtificial())
1253 addFlag(SPDie, dwarf::DW_AT_artificial);
1255 if (!SP->isLocalToUnit())
1256 addFlag(SPDie, dwarf::DW_AT_external);
1258 if (DD->useAppleExtensionAttributes()) {
1259 if (SP->isOptimized())
1260 addFlag(SPDie, dwarf::DW_AT_APPLE_optimized);
1262 if (unsigned isa = Asm->getISAEncoding())
1263 addUInt(SPDie, dwarf::DW_AT_APPLE_isa, dwarf::DW_FORM_flag, isa);
1266 if (SP->isLValueReference())
1267 addFlag(SPDie, dwarf::DW_AT_reference);
1269 if (SP->isRValueReference())
1270 addFlag(SPDie, dwarf::DW_AT_rvalue_reference);
1272 if (SP->isNoReturn())
1273 addFlag(SPDie, dwarf::DW_AT_noreturn);
1275 if (SP->isProtected())
1276 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1277 dwarf::DW_ACCESS_protected);
1278 else if (SP->isPrivate())
1279 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1280 dwarf::DW_ACCESS_private);
1281 else if (SP->isPublic())
1282 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1283 dwarf::DW_ACCESS_public);
1285 if (SP->isExplicit())
1286 addFlag(SPDie, dwarf::DW_AT_explicit);
1288 if (SP->isMainSubprogram())
1289 addFlag(SPDie, dwarf::DW_AT_main_subprogram);
1292 void DwarfUnit::constructSubrangeDIE(DIE &Buffer, const DISubrange *SR,
1294 DIE &DW_Subrange = createAndAddDIE(dwarf::DW_TAG_subrange_type, Buffer);
1295 addDIEEntry(DW_Subrange, dwarf::DW_AT_type, *IndexTy);
1297 // The LowerBound value defines the lower bounds which is typically zero for
1298 // C/C++. The Count value is the number of elements. Values are 64 bit. If
1299 // Count == -1 then the array is unbounded and we do not emit
1300 // DW_AT_lower_bound and DW_AT_count attributes.
1301 int64_t LowerBound = SR->getLowerBound();
1302 int64_t DefaultLowerBound = getDefaultLowerBound();
1303 int64_t Count = SR->getCount();
1305 if (DefaultLowerBound == -1 || LowerBound != DefaultLowerBound)
1306 addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, None, LowerBound);
1309 // FIXME: An unbounded array should reference the expression that defines
1311 addUInt(DW_Subrange, dwarf::DW_AT_count, None, Count);
1314 DIE *DwarfUnit::getIndexTyDie() {
1317 // Construct an integer type to use for indexes.
1318 IndexTyDie = &createAndAddDIE(dwarf::DW_TAG_base_type, getUnitDie());
1319 addString(*IndexTyDie, dwarf::DW_AT_name, "sizetype");
1320 addUInt(*IndexTyDie, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
1321 addUInt(*IndexTyDie, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
1322 dwarf::DW_ATE_unsigned);
1326 void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
1327 if (CTy->isVector())
1328 addFlag(Buffer, dwarf::DW_AT_GNU_vector);
1330 // Emit the element type.
1331 addType(Buffer, resolve(CTy->getBaseType()));
1333 // Get an anonymous type for index type.
1334 // FIXME: This type should be passed down from the front end
1335 // as different languages may have different sizes for indexes.
1336 DIE *IdxTy = getIndexTyDie();
1338 // Add subranges to array type.
1339 DINodeArray Elements = CTy->getElements();
1340 for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
1341 // FIXME: Should this really be such a loose cast?
1342 if (auto *Element = dyn_cast_or_null<DINode>(Elements[i]))
1343 if (Element->getTag() == dwarf::DW_TAG_subrange_type)
1344 constructSubrangeDIE(Buffer, cast<DISubrange>(Element), IdxTy);
1348 void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
1349 DINodeArray Elements = CTy->getElements();
1351 // Add enumerators to enumeration type.
1352 for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
1353 auto *Enum = dyn_cast_or_null<DIEnumerator>(Elements[i]);
1355 DIE &Enumerator = createAndAddDIE(dwarf::DW_TAG_enumerator, Buffer);
1356 StringRef Name = Enum->getName();
1357 addString(Enumerator, dwarf::DW_AT_name, Name);
1358 int64_t Value = Enum->getValue();
1359 addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
1363 const DIType *DTy = resolve(CTy->getBaseType());
1365 addType(Buffer, DTy);
1366 addFlag(Buffer, dwarf::DW_AT_enum_class);
1370 void DwarfUnit::constructContainingTypeDIEs() {
1371 for (auto CI = ContainingTypeMap.begin(), CE = ContainingTypeMap.end();
1373 DIE &SPDie = *CI->first;
1374 const DINode *D = CI->second;
1377 DIE *NDie = getDIE(D);
1380 addDIEEntry(SPDie, dwarf::DW_AT_containing_type, *NDie);
1384 void DwarfUnit::constructMemberDIE(DIE &Buffer, const DIDerivedType *DT) {
1385 DIE &MemberDie = createAndAddDIE(DT->getTag(), Buffer);
1386 StringRef Name = DT->getName();
1388 addString(MemberDie, dwarf::DW_AT_name, Name);
1390 addType(MemberDie, resolve(DT->getBaseType()));
1392 addSourceLine(MemberDie, DT);
1394 if (DT->getTag() == dwarf::DW_TAG_inheritance && DT->isVirtual()) {
1396 // For C++, virtual base classes are not at fixed offset. Use following
1397 // expression to extract appropriate offset from vtable.
1398 // BaseAddr = ObAddr + *((*ObAddr) - Offset)
1400 DIELoc *VBaseLocationDie = new (DIEValueAllocator) DIELoc;
1401 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
1402 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1403 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1404 addUInt(*VBaseLocationDie, dwarf::DW_FORM_udata, DT->getOffsetInBits());
1405 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
1406 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1407 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
1409 addBlock(MemberDie, dwarf::DW_AT_data_member_location, VBaseLocationDie);
1411 uint64_t Size = DT->getSizeInBits();
1412 uint64_t FieldSize = DD->getBaseTypeSize(DT);
1413 uint32_t AlignInBytes = DT->getAlignInBytes();
1414 uint64_t OffsetInBytes;
1416 bool IsBitfield = FieldSize && Size != FieldSize;
1418 // Handle bitfield, assume bytes are 8 bits.
1419 if (DD->useDWARF2Bitfields())
1420 addUInt(MemberDie, dwarf::DW_AT_byte_size, None, FieldSize/8);
1421 addUInt(MemberDie, dwarf::DW_AT_bit_size, None, Size);
1423 uint64_t Offset = DT->getOffsetInBits();
1424 // We can't use DT->getAlignInBits() here: AlignInBits for member type
1425 // is non-zero if and only if alignment was forced (e.g. _Alignas()),
1426 // which can't be done with bitfields. Thus we use FieldSize here.
1427 uint32_t AlignInBits = FieldSize;
1428 uint32_t AlignMask = ~(AlignInBits - 1);
1429 // The bits from the start of the storage unit to the start of the field.
1430 uint64_t StartBitOffset = Offset - (Offset & AlignMask);
1431 // The byte offset of the field's aligned storage unit inside the struct.
1432 OffsetInBytes = (Offset - StartBitOffset) / 8;
1434 if (DD->useDWARF2Bitfields()) {
1435 uint64_t HiMark = (Offset + FieldSize) & AlignMask;
1436 uint64_t FieldOffset = (HiMark - FieldSize);
1437 Offset -= FieldOffset;
1439 // Maybe we need to work from the other end.
1440 if (Asm->getDataLayout().isLittleEndian())
1441 Offset = FieldSize - (Offset + Size);
1443 addUInt(MemberDie, dwarf::DW_AT_bit_offset, None, Offset);
1444 OffsetInBytes = FieldOffset >> 3;
1446 addUInt(MemberDie, dwarf::DW_AT_data_bit_offset, None, Offset);
1449 // This is not a bitfield.
1450 OffsetInBytes = DT->getOffsetInBits() / 8;
1452 addUInt(MemberDie, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata,
1456 if (DD->getDwarfVersion() <= 2) {
1457 DIELoc *MemLocationDie = new (DIEValueAllocator) DIELoc;
1458 addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
1459 addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes);
1460 addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie);
1461 } else if (!IsBitfield || DD->useDWARF2Bitfields())
1462 addUInt(MemberDie, dwarf::DW_AT_data_member_location, None,
1466 if (DT->isProtected())
1467 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1468 dwarf::DW_ACCESS_protected);
1469 else if (DT->isPrivate())
1470 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1471 dwarf::DW_ACCESS_private);
1472 // Otherwise C++ member and base classes are considered public.
1473 else if (DT->isPublic())
1474 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1475 dwarf::DW_ACCESS_public);
1476 if (DT->isVirtual())
1477 addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1,
1478 dwarf::DW_VIRTUALITY_virtual);
1480 // Objective-C properties.
1481 if (DINode *PNode = DT->getObjCProperty())
1482 if (DIE *PDie = getDIE(PNode))
1483 MemberDie.addValue(DIEValueAllocator, dwarf::DW_AT_APPLE_property,
1484 dwarf::DW_FORM_ref4, DIEEntry(*PDie));
1486 if (DT->isArtificial())
1487 addFlag(MemberDie, dwarf::DW_AT_artificial);
1490 DIE *DwarfUnit::getOrCreateStaticMemberDIE(const DIDerivedType *DT) {
1494 // Construct the context before querying for the existence of the DIE in case
1495 // such construction creates the DIE.
1496 DIE *ContextDIE = getOrCreateContextDIE(resolve(DT->getScope()));
1497 assert(dwarf::isType(ContextDIE->getTag()) &&
1498 "Static member should belong to a type.");
1500 if (DIE *StaticMemberDIE = getDIE(DT))
1501 return StaticMemberDIE;
1503 DIE &StaticMemberDIE = createAndAddDIE(DT->getTag(), *ContextDIE, DT);
1505 const DIType *Ty = resolve(DT->getBaseType());
1507 addString(StaticMemberDIE, dwarf::DW_AT_name, DT->getName());
1508 addType(StaticMemberDIE, Ty);
1509 addSourceLine(StaticMemberDIE, DT);
1510 addFlag(StaticMemberDIE, dwarf::DW_AT_external);
1511 addFlag(StaticMemberDIE, dwarf::DW_AT_declaration);
1513 // FIXME: We could omit private if the parent is a class_type, and
1514 // public if the parent is something else.
1515 if (DT->isProtected())
1516 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1517 dwarf::DW_ACCESS_protected);
1518 else if (DT->isPrivate())
1519 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1520 dwarf::DW_ACCESS_private);
1521 else if (DT->isPublic())
1522 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1523 dwarf::DW_ACCESS_public);
1525 if (const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(DT->getConstant()))
1526 addConstantValue(StaticMemberDIE, CI, Ty);
1527 if (const ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(DT->getConstant()))
1528 addConstantFPValue(StaticMemberDIE, CFP);
1530 if (uint32_t AlignInBytes = DT->getAlignInBytes())
1531 addUInt(StaticMemberDIE, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata,
1534 return &StaticMemberDIE;
1537 void DwarfUnit::emitCommonHeader(bool UseOffsets, dwarf::UnitType UT) {
1538 // Emit size of content not including length itself
1539 Asm->OutStreamer->AddComment("Length of Unit");
1540 Asm->EmitInt32(getHeaderSize() + getUnitDie().getSize());
1542 Asm->OutStreamer->AddComment("DWARF version number");
1543 unsigned Version = DD->getDwarfVersion();
1544 Asm->EmitInt16(Version);
1546 // DWARF v5 reorders the address size and adds a unit type.
1548 Asm->OutStreamer->AddComment("DWARF Unit Type");
1550 Asm->OutStreamer->AddComment("Address Size (in bytes)");
1551 Asm->EmitInt8(Asm->MAI->getCodePointerSize());
1554 // We share one abbreviations table across all units so it's always at the
1555 // start of the section. Use a relocatable offset where needed to ensure
1556 // linking doesn't invalidate that offset.
1557 Asm->OutStreamer->AddComment("Offset Into Abbrev. Section");
1558 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1562 Asm->emitDwarfSymbolReference(
1563 TLOF.getDwarfAbbrevSection()->getBeginSymbol(), false);
1566 Asm->OutStreamer->AddComment("Address Size (in bytes)");
1567 Asm->EmitInt8(Asm->MAI->getCodePointerSize());
1571 void DwarfTypeUnit::emitHeader(bool UseOffsets) {
1572 DwarfUnit::emitCommonHeader(UseOffsets,
1573 DD->useSplitDwarf() ? dwarf::DW_UT_split_type
1574 : dwarf::DW_UT_type);
1575 Asm->OutStreamer->AddComment("Type Signature");
1576 Asm->OutStreamer->EmitIntValue(TypeSignature, sizeof(TypeSignature));
1577 Asm->OutStreamer->AddComment("Type DIE Offset");
1578 // In a skeleton type unit there is no type DIE so emit a zero offset.
1579 Asm->OutStreamer->EmitIntValue(Ty ? Ty->getOffset() : 0,
1580 sizeof(Ty->getOffset()));
1583 bool DwarfTypeUnit::isDwoUnit() const {
1584 // Since there are no skeleton type units, all type units are dwo type units
1585 // when split DWARF is being used.
1586 return DD->useSplitDwarf();
1589 void DwarfTypeUnit::addGlobalName(StringRef Name, const DIE &Die,
1590 const DIScope *Context) {
1591 getCU().addGlobalNameForTypeUnit(Name, Context);
1594 void DwarfTypeUnit::addGlobalType(const DIType *Ty, const DIE &Die,
1595 const DIScope *Context) {
1596 getCU().addGlobalTypeUnitType(Ty, Context);
1599 const MCSymbol *DwarfUnit::getCrossSectionRelativeBaseAddress() const {
1600 if (!Asm->MAI->doesDwarfUseRelocationsAcrossSections())
1604 return getSection()->getBeginSymbol();