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"
16 #include "DwarfAccelTable.h"
17 #include "DwarfCompileUnit.h"
18 #include "DwarfDebug.h"
19 #include "llvm/ADT/APFloat.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/DIBuilder.h"
22 #include "llvm/IR/DataLayout.h"
23 #include "llvm/IR/GlobalVariable.h"
24 #include "llvm/IR/Instructions.h"
25 #include "llvm/IR/Mangler.h"
26 #include "llvm/MC/MCAsmInfo.h"
27 #include "llvm/MC/MCContext.h"
28 #include "llvm/MC/MCSection.h"
29 #include "llvm/MC/MCStreamer.h"
30 #include "llvm/Support/CommandLine.h"
31 #include "llvm/Target/TargetFrameLowering.h"
32 #include "llvm/Target/TargetLoweringObjectFile.h"
33 #include "llvm/Target/TargetMachine.h"
34 #include "llvm/Target/TargetRegisterInfo.h"
35 #include "llvm/Target/TargetSubtargetInfo.h"
39 #define DEBUG_TYPE "dwarfdebug"
42 GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
43 cl::desc("Generate DWARF4 type units."),
46 /// Unit - Unit constructor.
47 DwarfUnit::DwarfUnit(unsigned UID, dwarf::Tag UnitTag, DICompileUnit Node,
48 AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU)
49 : UniqueID(UID), CUNode(Node), UnitDie(UnitTag), DebugInfoOffset(0), Asm(A),
50 DD(DW), DU(DWU), IndexTyDie(nullptr), Section(nullptr) {
51 assert(UnitTag == dwarf::DW_TAG_compile_unit ||
52 UnitTag == dwarf::DW_TAG_type_unit);
53 DIEIntegerOne = new (DIEValueAllocator) DIEInteger(1);
56 DwarfTypeUnit::DwarfTypeUnit(unsigned UID, DwarfCompileUnit &CU, AsmPrinter *A,
57 DwarfDebug *DW, DwarfFile *DWU,
58 MCDwarfDwoLineTable *SplitLineTable)
59 : DwarfUnit(UID, dwarf::DW_TAG_type_unit, CU.getCUNode(), A, DW, DWU),
60 CU(CU), SplitLineTable(SplitLineTable) {
62 addSectionOffset(UnitDie, dwarf::DW_AT_stmt_list, 0);
65 /// ~Unit - Destructor for compile unit.
66 DwarfUnit::~DwarfUnit() {
67 for (unsigned j = 0, M = DIEBlocks.size(); j < M; ++j)
68 DIEBlocks[j]->~DIEBlock();
69 for (unsigned j = 0, M = DIELocs.size(); j < M; ++j)
70 DIELocs[j]->~DIELoc();
73 /// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
74 /// information entry.
75 DIEEntry *DwarfUnit::createDIEEntry(DIE &Entry) {
76 DIEEntry *Value = new (DIEValueAllocator) DIEEntry(Entry);
80 /// getDefaultLowerBound - Return the default lower bound for an array. If the
81 /// DWARF version doesn't handle the language, return -1.
82 int64_t DwarfUnit::getDefaultLowerBound() const {
83 switch (getLanguage()) {
87 case dwarf::DW_LANG_C89:
88 case dwarf::DW_LANG_C99:
89 case dwarf::DW_LANG_C:
90 case dwarf::DW_LANG_C_plus_plus:
91 case dwarf::DW_LANG_ObjC:
92 case dwarf::DW_LANG_ObjC_plus_plus:
95 case dwarf::DW_LANG_Fortran77:
96 case dwarf::DW_LANG_Fortran90:
97 case dwarf::DW_LANG_Fortran95:
100 // The languages below have valid values only if the DWARF version >= 4.
101 case dwarf::DW_LANG_Java:
102 case dwarf::DW_LANG_Python:
103 case dwarf::DW_LANG_UPC:
104 case dwarf::DW_LANG_D:
105 if (dwarf::DWARF_VERSION >= 4)
109 case dwarf::DW_LANG_Ada83:
110 case dwarf::DW_LANG_Ada95:
111 case dwarf::DW_LANG_Cobol74:
112 case dwarf::DW_LANG_Cobol85:
113 case dwarf::DW_LANG_Modula2:
114 case dwarf::DW_LANG_Pascal83:
115 case dwarf::DW_LANG_PLI:
116 if (dwarf::DWARF_VERSION >= 4)
124 /// Check whether the DIE for this MDNode can be shared across CUs.
125 static bool isShareableAcrossCUs(DIDescriptor D) {
126 // When the MDNode can be part of the type system, the DIE can be shared
128 // Combining type units and cross-CU DIE sharing is lower value (since
129 // cross-CU DIE sharing is used in LTO and removes type redundancy at that
130 // level already) but may be implementable for some value in projects
131 // building multiple independent libraries with LTO and then linking those
133 return (D.isType() ||
134 (D.isSubprogram() && !DISubprogram(D).isDefinition())) &&
135 !GenerateDwarfTypeUnits;
138 /// getDIE - Returns the debug information entry map slot for the
139 /// specified debug variable. We delegate the request to DwarfDebug
140 /// when the DIE for this MDNode can be shared across CUs. The mappings
141 /// will be kept in DwarfDebug for shareable DIEs.
142 DIE *DwarfUnit::getDIE(DIDescriptor D) const {
143 if (isShareableAcrossCUs(D))
144 return DU->getDIE(D);
145 return MDNodeToDieMap.lookup(D);
148 /// insertDIE - Insert DIE into the map. We delegate the request to DwarfDebug
149 /// when the DIE for this MDNode can be shared across CUs. The mappings
150 /// will be kept in DwarfDebug for shareable DIEs.
151 void DwarfUnit::insertDIE(DIDescriptor Desc, DIE *D) {
152 if (isShareableAcrossCUs(Desc)) {
153 DU->insertDIE(Desc, D);
156 MDNodeToDieMap.insert(std::make_pair(Desc, D));
159 /// addFlag - Add a flag that is true.
160 void DwarfUnit::addFlag(DIE &Die, dwarf::Attribute Attribute) {
161 if (DD->getDwarfVersion() >= 4)
162 Die.addValue(Attribute, dwarf::DW_FORM_flag_present, DIEIntegerOne);
164 Die.addValue(Attribute, dwarf::DW_FORM_flag, DIEIntegerOne);
167 /// addUInt - Add an unsigned integer attribute data and value.
169 void DwarfUnit::addUInt(DIE &Die, dwarf::Attribute Attribute,
170 Optional<dwarf::Form> Form, uint64_t Integer) {
172 Form = DIEInteger::BestForm(false, Integer);
173 DIEValue *Value = Integer == 1 ? DIEIntegerOne : new (DIEValueAllocator)
175 Die.addValue(Attribute, *Form, Value);
178 void DwarfUnit::addUInt(DIE &Block, dwarf::Form Form, uint64_t Integer) {
179 addUInt(Block, (dwarf::Attribute)0, Form, Integer);
182 /// addSInt - Add an signed integer attribute data and value.
184 void DwarfUnit::addSInt(DIE &Die, dwarf::Attribute Attribute,
185 Optional<dwarf::Form> Form, int64_t Integer) {
187 Form = DIEInteger::BestForm(true, Integer);
188 DIEValue *Value = new (DIEValueAllocator) DIEInteger(Integer);
189 Die.addValue(Attribute, *Form, Value);
192 void DwarfUnit::addSInt(DIELoc &Die, Optional<dwarf::Form> Form,
194 addSInt(Die, (dwarf::Attribute)0, Form, Integer);
197 /// addString - Add a string attribute data and value. We always emit a
198 /// reference to the string pool instead of immediate strings so that DIEs have
199 /// more predictable sizes. In the case of split dwarf we emit an index
200 /// into another table which gets us the static offset into the string
202 void DwarfUnit::addString(DIE &Die, dwarf::Attribute Attribute,
205 return addLocalString(Die, Attribute, String);
207 addIndexedString(Die, Attribute, String);
210 void DwarfUnit::addIndexedString(DIE &Die, dwarf::Attribute Attribute,
212 unsigned idx = DU->getStringPool().getIndex(*Asm, String);
213 DIEValue *Value = new (DIEValueAllocator) DIEInteger(idx);
214 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
215 Die.addValue(Attribute, dwarf::DW_FORM_GNU_str_index, Str);
218 /// addLocalString - Add a string attribute data and value. This is guaranteed
219 /// to be in the local string pool instead of indirected.
220 void DwarfUnit::addLocalString(DIE &Die, dwarf::Attribute Attribute,
222 MCSymbol *Symb = DU->getStringPool().getSymbol(*Asm, String);
224 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
225 Value = new (DIEValueAllocator) DIELabel(Symb);
227 Value = new (DIEValueAllocator) DIEDelta(Symb, DD->getDebugStrSym());
228 DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String);
229 Die.addValue(Attribute, dwarf::DW_FORM_strp, Str);
232 /// addLabel - Add a Dwarf label attribute data and value.
234 void DwarfUnit::addLabel(DIE &Die, dwarf::Attribute Attribute, dwarf::Form Form,
235 const MCSymbol *Label) {
236 DIEValue *Value = new (DIEValueAllocator) DIELabel(Label);
237 Die.addValue(Attribute, Form, Value);
240 void DwarfUnit::addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label) {
241 addLabel(Die, (dwarf::Attribute)0, Form, Label);
244 /// addSectionOffset - Add an offset into a section attribute data and value.
246 void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
248 if (DD->getDwarfVersion() >= 4)
249 addUInt(Die, Attribute, dwarf::DW_FORM_sec_offset, Integer);
251 addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
254 unsigned DwarfTypeUnit::getOrCreateSourceID(StringRef FileName, StringRef DirName) {
255 return SplitLineTable ? SplitLineTable->getFile(DirName, FileName)
256 : getCU().getOrCreateSourceID(FileName, DirName);
259 /// addOpAddress - Add a dwarf op address data and value using the
260 /// form given and an op of either DW_FORM_addr or DW_FORM_GNU_addr_index.
262 void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) {
263 if (!DD->useSplitDwarf()) {
264 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
265 addLabel(Die, dwarf::DW_FORM_udata, Sym);
267 addUInt(Die, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_addr_index);
268 addUInt(Die, dwarf::DW_FORM_GNU_addr_index,
269 DD->getAddressPool().getIndex(Sym));
273 void DwarfUnit::addLabelDelta(DIE &Die, dwarf::Attribute Attribute,
274 const MCSymbol *Hi, const MCSymbol *Lo) {
275 DIEValue *Value = new (DIEValueAllocator) DIEDelta(Hi, Lo);
276 Die.addValue(Attribute, dwarf::DW_FORM_data4, Value);
279 /// addDIEEntry - Add a DIE attribute data and value.
281 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry) {
282 addDIEEntry(Die, Attribute, createDIEEntry(Entry));
285 void DwarfUnit::addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type) {
286 // Flag the type unit reference as a declaration so that if it contains
287 // members (implicit special members, static data member definitions, member
288 // declarations for definitions in this CU, etc) consumers don't get confused
289 // and think this is a full definition.
290 addFlag(Die, dwarf::DW_AT_declaration);
292 Die.addValue(dwarf::DW_AT_signature, dwarf::DW_FORM_ref_sig8,
293 new (DIEValueAllocator) DIETypeSignature(Type));
296 void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
298 const DIE *DieCU = Die.getUnitOrNull();
299 const DIE *EntryCU = Entry->getEntry().getUnitOrNull();
301 // We assume that Die belongs to this CU, if it is not linked to any CU yet.
302 DieCU = &getUnitDie();
304 EntryCU = &getUnitDie();
305 Die.addValue(Attribute,
306 EntryCU == DieCU ? dwarf::DW_FORM_ref4 : dwarf::DW_FORM_ref_addr,
310 /// Create a DIE with the given Tag, add the DIE to its parent, and
311 /// call insertDIE if MD is not null.
312 DIE &DwarfUnit::createAndAddDIE(unsigned Tag, DIE &Parent, DIDescriptor N) {
313 assert(Tag != dwarf::DW_TAG_auto_variable &&
314 Tag != dwarf::DW_TAG_arg_variable);
315 Parent.addChild(make_unique<DIE>((dwarf::Tag)Tag));
316 DIE &Die = *Parent.getChildren().back();
322 /// addBlock - Add block data.
324 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Loc) {
325 Loc->ComputeSize(Asm);
326 DIELocs.push_back(Loc); // Memoize so we can call the destructor later on.
327 Die.addValue(Attribute, Loc->BestForm(DD->getDwarfVersion()), Loc);
330 void DwarfUnit::addBlock(DIE &Die, dwarf::Attribute Attribute,
332 Block->ComputeSize(Asm);
333 DIEBlocks.push_back(Block); // Memoize so we can call the destructor later on.
334 Die.addValue(Attribute, Block->BestForm(), Block);
337 /// addSourceLine - Add location information to specified debug information
339 void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, StringRef File,
340 StringRef Directory) {
344 unsigned FileID = getOrCreateSourceID(File, Directory);
345 assert(FileID && "Invalid file id");
346 addUInt(Die, dwarf::DW_AT_decl_file, None, FileID);
347 addUInt(Die, dwarf::DW_AT_decl_line, None, Line);
350 /// addSourceLine - Add location information to specified debug information
352 void DwarfUnit::addSourceLine(DIE &Die, DIVariable V) {
353 assert(V.isVariable());
355 addSourceLine(Die, V.getLineNumber(), V.getContext().getFilename(),
356 V.getContext().getDirectory());
359 /// addSourceLine - Add location information to specified debug information
361 void DwarfUnit::addSourceLine(DIE &Die, DIGlobalVariable G) {
362 assert(G.isGlobalVariable());
364 addSourceLine(Die, G.getLineNumber(), G.getFilename(), G.getDirectory());
367 /// addSourceLine - Add location information to specified debug information
369 void DwarfUnit::addSourceLine(DIE &Die, DISubprogram SP) {
370 assert(SP.isSubprogram());
372 addSourceLine(Die, SP.getLineNumber(), SP.getFilename(), SP.getDirectory());
375 /// addSourceLine - Add location information to specified debug information
377 void DwarfUnit::addSourceLine(DIE &Die, DIType Ty) {
380 addSourceLine(Die, Ty.getLineNumber(), Ty.getFilename(), Ty.getDirectory());
383 /// addSourceLine - Add location information to specified debug information
385 void DwarfUnit::addSourceLine(DIE &Die, DIObjCProperty Ty) {
386 assert(Ty.isObjCProperty());
388 DIFile File = Ty.getFile();
389 addSourceLine(Die, Ty.getLineNumber(), File.getFilename(),
390 File.getDirectory());
393 /// addSourceLine - Add location information to specified debug information
395 void DwarfUnit::addSourceLine(DIE &Die, DINameSpace NS) {
398 addSourceLine(Die, NS.getLineNumber(), NS.getFilename(), NS.getDirectory());
401 /// addRegisterOp - Add register operand.
402 // FIXME: Ideally, this would share the implementation with
403 // AsmPrinter::EmitDwarfRegOpPiece.
404 bool DwarfUnit::addRegisterOpPiece(DIELoc &TheDie, unsigned Reg,
405 unsigned SizeInBits, unsigned OffsetInBits) {
406 const TargetRegisterInfo *RI = Asm->TM.getSubtargetImpl()->getRegisterInfo();
407 int DWReg = RI->getDwarfRegNum(Reg, false);
408 bool isSubRegister = DWReg < 0;
412 // Go up the super-register chain until we hit a valid dwarf register number.
413 for (MCSuperRegIterator SR(Reg, RI); SR.isValid() && DWReg < 0; ++SR) {
414 DWReg = RI->getDwarfRegNum(*SR, false);
416 Idx = RI->getSubRegIndex(*SR, Reg);
424 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_reg0 + DWReg);
426 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_regx);
427 addUInt(TheDie, dwarf::DW_FORM_udata, DWReg);
431 bool isPiece = SizeInBits > 0;
432 if (isSubRegister || isPiece) {
433 const unsigned SizeOfByte = 8;
434 unsigned RegSizeInBits = RI->getSubRegIdxSize(Idx);
435 unsigned RegOffsetInBits = RI->getSubRegIdxOffset(Idx);
436 unsigned PieceSizeInBits = std::max(SizeInBits, RegSizeInBits);
437 unsigned PieceOffsetInBits = OffsetInBits ? OffsetInBits : RegOffsetInBits;
438 assert(RegSizeInBits >= SizeInBits && "register smaller than value");
440 if (RegOffsetInBits != PieceOffsetInBits) {
441 // Manually shift the value into place, since the DW_OP_piece
442 // describes the part of the variable, not the position of the
444 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
445 addUInt(TheDie, dwarf::DW_FORM_data1, RegOffsetInBits);
446 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_shr);
449 if (PieceOffsetInBits > 0 || PieceSizeInBits % SizeOfByte) {
450 assert(PieceSizeInBits > 0 && "piece has zero size");
451 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_bit_piece);
452 addUInt(TheDie, dwarf::DW_FORM_data1, PieceSizeInBits);
453 addUInt(TheDie, dwarf::DW_FORM_data1, PieceOffsetInBits);
455 assert(PieceSizeInBits > 0 && "piece has zero size");
456 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_piece);
457 addUInt(TheDie, dwarf::DW_FORM_data1, PieceSizeInBits/SizeOfByte);
463 /// addRegisterOffset - Add register offset.
464 bool DwarfUnit::addRegisterOffset(DIELoc &TheDie, unsigned Reg,
466 const TargetRegisterInfo *TRI = Asm->TM.getSubtargetImpl()->getRegisterInfo();
467 int DWReg = TRI->getDwarfRegNum(Reg, false);
471 if (Reg == TRI->getFrameRegister(*Asm->MF))
472 // If variable offset is based in frame register then use fbreg.
473 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_fbreg);
475 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + DWReg);
477 addUInt(TheDie, dwarf::DW_FORM_data1, dwarf::DW_OP_bregx);
478 addUInt(TheDie, dwarf::DW_FORM_udata, DWReg);
480 addSInt(TheDie, dwarf::DW_FORM_sdata, Offset);
484 /* Byref variables, in Blocks, are declared by the programmer as "SomeType
485 VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
486 gives the variable VarName either the struct, or a pointer to the struct, as
487 its type. This is necessary for various behind-the-scenes things the
488 compiler needs to do with by-reference variables in Blocks.
490 However, as far as the original *programmer* is concerned, the variable
491 should still have type 'SomeType', as originally declared.
493 The function getBlockByrefType dives into the __Block_byref_x_VarName
494 struct to find the original type of the variable, which is then assigned to
495 the variable's Debug Information Entry as its real type. So far, so good.
496 However now the debugger will expect the variable VarName to have the type
497 SomeType. So we need the location attribute for the variable to be an
498 expression that explains to the debugger how to navigate through the
499 pointers and struct to find the actual variable of type SomeType.
501 The following function does just that. We start by getting
502 the "normal" location for the variable. This will be the location
503 of either the struct __Block_byref_x_VarName or the pointer to the
504 struct __Block_byref_x_VarName.
506 The struct will look something like:
508 struct __Block_byref_x_VarName {
510 struct __Block_byref_x_VarName *forwarding;
511 ... <various other fields>
513 ... <maybe more fields>
516 If we are given the struct directly (as our starting point) we
517 need to tell the debugger to:
519 1). Add the offset of the forwarding field.
521 2). Follow that pointer to get the real __Block_byref_x_VarName
522 struct to use (the real one may have been copied onto the heap).
524 3). Add the offset for the field VarName, to find the actual variable.
526 If we started with a pointer to the struct, then we need to
527 dereference that pointer first, before the other steps.
528 Translating this into DWARF ops, we will need to append the following
529 to the current location description for the variable:
531 DW_OP_deref -- optional, if we start with a pointer
532 DW_OP_plus_uconst <forward_fld_offset>
534 DW_OP_plus_uconst <varName_fld_offset>
536 That is what this function does. */
538 /// addBlockByrefAddress - Start with the address based on the location
539 /// provided, and generate the DWARF information necessary to find the
540 /// actual Block variable (navigating the Block struct) based on the
541 /// starting location. Add the DWARF information to the die. For
542 /// more information, read large comment just above here.
544 void DwarfUnit::addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
545 dwarf::Attribute Attribute,
546 const MachineLocation &Location) {
547 DIType Ty = DV.getType();
549 uint16_t Tag = Ty.getTag();
550 bool isPointer = false;
552 StringRef varName = DV.getName();
554 if (Tag == dwarf::DW_TAG_pointer_type) {
555 DIDerivedType DTy(Ty);
556 TmpTy = resolve(DTy.getTypeDerivedFrom());
560 DICompositeType blockStruct(TmpTy);
562 // Find the __forwarding field and the variable field in the __Block_byref
564 DIArray Fields = blockStruct.getElements();
565 DIDerivedType varField;
566 DIDerivedType forwardingField;
568 for (unsigned i = 0, N = Fields.getNumElements(); i < N; ++i) {
569 DIDerivedType DT(Fields.getElement(i));
570 StringRef fieldName = DT.getName();
571 if (fieldName == "__forwarding")
572 forwardingField = DT;
573 else if (fieldName == varName)
577 // Get the offsets for the forwarding field and the variable field.
578 unsigned forwardingFieldOffset = forwardingField.getOffsetInBits() >> 3;
579 unsigned varFieldOffset = varField.getOffsetInBits() >> 2;
581 // Decode the original location, and use that as the start of the byref
582 // variable's location.
583 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
586 if (Location.isReg())
587 validReg = addRegisterOpPiece(*Loc, Location.getReg());
589 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
594 // If we started with a pointer to the __Block_byref... struct, then
595 // the first thing we need to do is dereference the pointer (DW_OP_deref).
597 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
599 // Next add the offset for the '__forwarding' field:
600 // DW_OP_plus_uconst ForwardingFieldOffset. Note there's no point in
601 // adding the offset if it's 0.
602 if (forwardingFieldOffset > 0) {
603 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
604 addUInt(*Loc, dwarf::DW_FORM_udata, forwardingFieldOffset);
607 // Now dereference the __forwarding field to get to the real __Block_byref
608 // struct: DW_OP_deref.
609 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
611 // Now that we've got the real __Block_byref... struct, add the offset
612 // for the variable's field to get to the location of the actual variable:
613 // DW_OP_plus_uconst varFieldOffset. Again, don't add if it's 0.
614 if (varFieldOffset > 0) {
615 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
616 addUInt(*Loc, dwarf::DW_FORM_udata, varFieldOffset);
619 // Now attach the location information to the DIE.
620 addBlock(Die, Attribute, Loc);
623 /// Return true if type encoding is unsigned.
624 static bool isUnsignedDIType(DwarfDebug *DD, DIType Ty) {
625 DIDerivedType DTy(Ty);
626 if (DTy.isDerivedType()) {
627 dwarf::Tag T = (dwarf::Tag)Ty.getTag();
628 // Encode pointer constants as unsigned bytes. This is used at least for
629 // null pointer constant emission.
630 // FIXME: reference and rvalue_reference /probably/ shouldn't be allowed
631 // here, but accept them for now due to a bug in SROA producing bogus
633 if (T == dwarf::DW_TAG_pointer_type ||
634 T == dwarf::DW_TAG_ptr_to_member_type ||
635 T == dwarf::DW_TAG_reference_type ||
636 T == dwarf::DW_TAG_rvalue_reference_type)
638 assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
639 T == dwarf::DW_TAG_volatile_type ||
640 T == dwarf::DW_TAG_restrict_type ||
641 T == dwarf::DW_TAG_enumeration_type);
642 if (DITypeRef Deriv = DTy.getTypeDerivedFrom())
643 return isUnsignedDIType(DD, DD->resolve(Deriv));
644 // FIXME: Enums without a fixed underlying type have unknown signedness
645 // here, leading to incorrectly emitted constants.
646 assert(DTy.getTag() == dwarf::DW_TAG_enumeration_type);
651 assert(BTy.isBasicType());
652 unsigned Encoding = BTy.getEncoding();
653 assert((Encoding == dwarf::DW_ATE_unsigned ||
654 Encoding == dwarf::DW_ATE_unsigned_char ||
655 Encoding == dwarf::DW_ATE_signed ||
656 Encoding == dwarf::DW_ATE_signed_char ||
657 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean) &&
658 "Unsupported encoding");
659 return (Encoding == dwarf::DW_ATE_unsigned ||
660 Encoding == dwarf::DW_ATE_unsigned_char ||
661 Encoding == dwarf::DW_ATE_UTF || Encoding == dwarf::DW_ATE_boolean);
664 /// If this type is derived from a base type then return base type size.
665 static uint64_t getBaseTypeSize(DwarfDebug *DD, DIDerivedType Ty) {
666 unsigned Tag = Ty.getTag();
668 if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
669 Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
670 Tag != dwarf::DW_TAG_restrict_type)
671 return Ty.getSizeInBits();
673 DIType BaseType = DD->resolve(Ty.getTypeDerivedFrom());
675 // If this type is not derived from any type or the type is a declaration then
676 // take conservative approach.
677 if (!BaseType.isValid() || BaseType.isForwardDecl())
678 return Ty.getSizeInBits();
680 // If this is a derived type, go ahead and get the base type, unless it's a
681 // reference then it's just the size of the field. Pointer types have no need
682 // of this since they're a different type of qualification on the type.
683 if (BaseType.getTag() == dwarf::DW_TAG_reference_type ||
684 BaseType.getTag() == dwarf::DW_TAG_rvalue_reference_type)
685 return Ty.getSizeInBits();
687 if (BaseType.isDerivedType())
688 return getBaseTypeSize(DD, DIDerivedType(BaseType));
690 return BaseType.getSizeInBits();
693 /// addConstantFPValue - Add constant value entry in variable DIE.
694 void DwarfUnit::addConstantFPValue(DIE &Die, const MachineOperand &MO) {
695 assert(MO.isFPImm() && "Invalid machine operand!");
696 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
697 APFloat FPImm = MO.getFPImm()->getValueAPF();
699 // Get the raw data form of the floating point.
700 const APInt FltVal = FPImm.bitcastToAPInt();
701 const char *FltPtr = (const char *)FltVal.getRawData();
703 int NumBytes = FltVal.getBitWidth() / 8; // 8 bits per byte.
704 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
705 int Incr = (LittleEndian ? 1 : -1);
706 int Start = (LittleEndian ? 0 : NumBytes - 1);
707 int Stop = (LittleEndian ? NumBytes : -1);
709 // Output the constant to DWARF one byte at a time.
710 for (; Start != Stop; Start += Incr)
711 addUInt(*Block, dwarf::DW_FORM_data1, (unsigned char)0xFF & FltPtr[Start]);
713 addBlock(Die, dwarf::DW_AT_const_value, Block);
716 /// addConstantFPValue - Add constant value entry in variable DIE.
717 void DwarfUnit::addConstantFPValue(DIE &Die, const ConstantFP *CFP) {
718 // Pass this down to addConstantValue as an unsigned bag of bits.
719 addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
722 /// addConstantValue - Add constant value entry in variable DIE.
723 void DwarfUnit::addConstantValue(DIE &Die, const ConstantInt *CI, DIType Ty) {
724 addConstantValue(Die, CI->getValue(), Ty);
727 /// addConstantValue - Add constant value entry in variable DIE.
728 void DwarfUnit::addConstantValue(DIE &Die, const MachineOperand &MO,
730 assert(MO.isImm() && "Invalid machine operand!");
732 addConstantValue(Die, isUnsignedDIType(DD, Ty), MO.getImm());
735 void DwarfUnit::addConstantValue(DIE &Die, bool Unsigned, uint64_t Val) {
736 // FIXME: This is a bit conservative/simple - it emits negative values always
737 // sign extended to 64 bits rather than minimizing the number of bytes.
738 addUInt(Die, dwarf::DW_AT_const_value,
739 Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata, Val);
742 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, DIType Ty) {
743 addConstantValue(Die, Val, isUnsignedDIType(DD, Ty));
746 // addConstantValue - Add constant value entry in variable DIE.
747 void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
748 unsigned CIBitWidth = Val.getBitWidth();
749 if (CIBitWidth <= 64) {
750 addConstantValue(Die, Unsigned,
751 Unsigned ? Val.getZExtValue() : Val.getSExtValue());
755 DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
757 // Get the raw data form of the large APInt.
758 const uint64_t *Ptr64 = Val.getRawData();
760 int NumBytes = Val.getBitWidth() / 8; // 8 bits per byte.
761 bool LittleEndian = Asm->getDataLayout().isLittleEndian();
763 // Output the constant to DWARF one byte at a time.
764 for (int i = 0; i < NumBytes; i++) {
767 c = Ptr64[i / 8] >> (8 * (i & 7));
769 c = Ptr64[(NumBytes - 1 - i) / 8] >> (8 * ((NumBytes - 1 - i) & 7));
770 addUInt(*Block, dwarf::DW_FORM_data1, c);
773 addBlock(Die, dwarf::DW_AT_const_value, Block);
776 /// addTemplateParams - Add template parameters into buffer.
777 void DwarfUnit::addTemplateParams(DIE &Buffer, DIArray TParams) {
778 // Add template parameters.
779 for (unsigned i = 0, e = TParams.getNumElements(); i != e; ++i) {
780 DIDescriptor Element = TParams.getElement(i);
781 if (Element.isTemplateTypeParameter())
782 constructTemplateTypeParameterDIE(Buffer,
783 DITemplateTypeParameter(Element));
784 else if (Element.isTemplateValueParameter())
785 constructTemplateValueParameterDIE(Buffer,
786 DITemplateValueParameter(Element));
790 /// getOrCreateContextDIE - Get context owner's DIE.
791 DIE *DwarfUnit::getOrCreateContextDIE(DIScope Context) {
792 if (!Context || Context.isFile())
793 return &getUnitDie();
794 if (Context.isType())
795 return getOrCreateTypeDIE(DIType(Context));
796 if (Context.isNameSpace())
797 return getOrCreateNameSpace(DINameSpace(Context));
798 if (Context.isSubprogram())
799 return getOrCreateSubprogramDIE(DISubprogram(Context));
800 return getDIE(Context);
803 DIE *DwarfUnit::createTypeDIE(DICompositeType Ty) {
804 DIScope Context = resolve(Ty.getContext());
805 DIE *ContextDIE = getOrCreateContextDIE(Context);
807 if (DIE *TyDIE = getDIE(Ty))
811 DIE &TyDIE = createAndAddDIE(Ty.getTag(), *ContextDIE, Ty);
813 constructTypeDIE(TyDIE, Ty);
815 updateAcceleratorTables(Context, Ty, TyDIE);
819 /// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
821 DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
827 assert(Ty == resolve(Ty.getRef()) &&
828 "type was not uniqued, possible ODR violation.");
830 // DW_TAG_restrict_type is not supported in DWARF2
831 if (Ty.getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
832 return getOrCreateTypeDIE(resolve(DIDerivedType(Ty).getTypeDerivedFrom()));
834 // Construct the context before querying for the existence of the DIE in case
835 // such construction creates the DIE.
836 DIScope Context = resolve(Ty.getContext());
837 DIE *ContextDIE = getOrCreateContextDIE(Context);
840 if (DIE *TyDIE = getDIE(Ty))
844 DIE &TyDIE = createAndAddDIE(Ty.getTag(), *ContextDIE, Ty);
846 updateAcceleratorTables(Context, Ty, TyDIE);
848 if (Ty.isBasicType())
849 constructTypeDIE(TyDIE, DIBasicType(Ty));
850 else if (Ty.isCompositeType()) {
851 DICompositeType CTy(Ty);
852 if (GenerateDwarfTypeUnits && !Ty.isForwardDecl())
853 if (MDString *TypeId = CTy.getIdentifier()) {
854 DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);
855 // Skip updating the accelerator tables since this is not the full type.
858 constructTypeDIE(TyDIE, CTy);
860 assert(Ty.isDerivedType() && "Unknown kind of DIType");
861 constructTypeDIE(TyDIE, DIDerivedType(Ty));
867 void DwarfUnit::updateAcceleratorTables(DIScope Context, DIType Ty,
869 if (!Ty.getName().empty() && !Ty.isForwardDecl()) {
870 bool IsImplementation = 0;
871 if (Ty.isCompositeType()) {
872 DICompositeType CT(Ty);
873 // A runtime language of 0 actually means C/C++ and that any
874 // non-negative value is some version of Objective-C/C++.
875 IsImplementation = (CT.getRunTimeLang() == 0) || CT.isObjcClassComplete();
877 unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
878 DD->addAccelType(Ty.getName(), TyDIE, Flags);
880 if (!Context || Context.isCompileUnit() || Context.isFile() ||
881 Context.isNameSpace())
882 addGlobalType(Ty, TyDIE, Context);
886 /// addType - Add a new type attribute to the specified entity.
887 void DwarfUnit::addType(DIE &Entity, DIType Ty, dwarf::Attribute Attribute) {
888 assert(Ty && "Trying to add a type that doesn't exist?");
890 // Check for pre-existence.
891 DIEEntry *Entry = getDIEEntry(Ty);
892 // If it exists then use the existing value.
894 addDIEEntry(Entity, Attribute, Entry);
899 DIE *Buffer = getOrCreateTypeDIE(Ty);
902 Entry = createDIEEntry(*Buffer);
903 insertDIEEntry(Ty, Entry);
904 addDIEEntry(Entity, Attribute, Entry);
907 /// getParentContextString - Walks the metadata parent chain in a language
908 /// specific manner (using the compile unit language) and returns
909 /// it as a string. This is done at the metadata level because DIEs may
910 /// not currently have been added to the parent context and walking the
911 /// DIEs looking for names is more expensive than walking the metadata.
912 std::string DwarfUnit::getParentContextString(DIScope Context) const {
916 // FIXME: Decide whether to implement this for non-C++ languages.
917 if (getLanguage() != dwarf::DW_LANG_C_plus_plus)
921 SmallVector<DIScope, 1> Parents;
922 while (!Context.isCompileUnit()) {
923 Parents.push_back(Context);
924 if (Context.getContext())
925 Context = resolve(Context.getContext());
927 // Structure, etc types will have a NULL context if they're at the top
932 // Reverse iterate over our list to go from the outermost construct to the
934 for (SmallVectorImpl<DIScope>::reverse_iterator I = Parents.rbegin(),
938 StringRef Name = Ctx.getName();
939 if (Name.empty() && Ctx.isNameSpace())
940 Name = "(anonymous namespace)";
949 /// constructTypeDIE - Construct basic type die from DIBasicType.
950 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIBasicType BTy) {
951 // Get core information.
952 StringRef Name = BTy.getName();
953 // Add name if not anonymous or intermediate type.
955 addString(Buffer, dwarf::DW_AT_name, Name);
957 // An unspecified type only has a name attribute.
958 if (BTy.getTag() == dwarf::DW_TAG_unspecified_type)
961 addUInt(Buffer, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
964 uint64_t Size = BTy.getSizeInBits() >> 3;
965 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
968 /// constructTypeDIE - Construct derived type die from DIDerivedType.
969 void DwarfUnit::constructTypeDIE(DIE &Buffer, DIDerivedType DTy) {
970 // Get core information.
971 StringRef Name = DTy.getName();
972 uint64_t Size = DTy.getSizeInBits() >> 3;
973 uint16_t Tag = Buffer.getTag();
975 // Map to main type, void will not have a type.
976 DIType FromTy = resolve(DTy.getTypeDerivedFrom());
978 addType(Buffer, FromTy);
980 // Add name if not anonymous or intermediate type.
982 addString(Buffer, dwarf::DW_AT_name, Name);
984 // Add size if non-zero (derived types might be zero-sized.)
985 if (Size && Tag != dwarf::DW_TAG_pointer_type)
986 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
988 if (Tag == dwarf::DW_TAG_ptr_to_member_type)
989 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
990 *getOrCreateTypeDIE(resolve(DTy.getClassType())));
991 // Add source line info if available and TyDesc is not a forward declaration.
992 if (!DTy.isForwardDecl())
993 addSourceLine(Buffer, DTy);
996 /// constructSubprogramArguments - Construct function argument DIEs.
997 void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DITypeArray Args) {
998 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) {
999 DIType Ty = resolve(Args.getElement(i));
1001 assert(i == N-1 && "Unspecified parameter must be the last argument");
1002 createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
1004 DIE &Arg = createAndAddDIE(dwarf::DW_TAG_formal_parameter, Buffer);
1006 if (Ty.isArtificial())
1007 addFlag(Arg, dwarf::DW_AT_artificial);
1012 /// constructTypeDIE - Construct type DIE from DICompositeType.
1013 void DwarfUnit::constructTypeDIE(DIE &Buffer, DICompositeType CTy) {
1014 // Add name if not anonymous or intermediate type.
1015 StringRef Name = CTy.getName();
1017 uint64_t Size = CTy.getSizeInBits() >> 3;
1018 uint16_t Tag = Buffer.getTag();
1021 case dwarf::DW_TAG_array_type:
1022 constructArrayTypeDIE(Buffer, CTy);
1024 case dwarf::DW_TAG_enumeration_type:
1025 constructEnumTypeDIE(Buffer, CTy);
1027 case dwarf::DW_TAG_subroutine_type: {
1028 // Add return type. A void return won't have a type.
1029 DITypeArray Elements = DISubroutineType(CTy).getTypeArray();
1030 DIType RTy(resolve(Elements.getElement(0)));
1032 addType(Buffer, RTy);
1034 bool isPrototyped = true;
1035 if (Elements.getNumElements() == 2 &&
1036 !Elements.getElement(1))
1037 isPrototyped = false;
1039 constructSubprogramArguments(Buffer, Elements);
1041 // Add prototype flag if we're dealing with a C language and the
1042 // function has been prototyped.
1043 uint16_t Language = getLanguage();
1045 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1046 Language == dwarf::DW_LANG_ObjC))
1047 addFlag(Buffer, dwarf::DW_AT_prototyped);
1049 if (CTy.isLValueReference())
1050 addFlag(Buffer, dwarf::DW_AT_reference);
1052 if (CTy.isRValueReference())
1053 addFlag(Buffer, dwarf::DW_AT_rvalue_reference);
1055 case dwarf::DW_TAG_structure_type:
1056 case dwarf::DW_TAG_union_type:
1057 case dwarf::DW_TAG_class_type: {
1058 // Add elements to structure type.
1059 DIArray Elements = CTy.getElements();
1060 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1061 DIDescriptor Element = Elements.getElement(i);
1062 if (Element.isSubprogram())
1063 getOrCreateSubprogramDIE(DISubprogram(Element));
1064 else if (Element.isDerivedType()) {
1065 DIDerivedType DDTy(Element);
1066 if (DDTy.getTag() == dwarf::DW_TAG_friend) {
1067 DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
1068 addType(ElemDie, resolve(DDTy.getTypeDerivedFrom()),
1069 dwarf::DW_AT_friend);
1070 } else if (DDTy.isStaticMember()) {
1071 getOrCreateStaticMemberDIE(DDTy);
1073 constructMemberDIE(Buffer, DDTy);
1075 } else if (Element.isObjCProperty()) {
1076 DIObjCProperty Property(Element);
1077 DIE &ElemDie = createAndAddDIE(Property.getTag(), Buffer);
1078 StringRef PropertyName = Property.getObjCPropertyName();
1079 addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
1080 if (Property.getType())
1081 addType(ElemDie, Property.getType());
1082 addSourceLine(ElemDie, Property);
1083 StringRef GetterName = Property.getObjCPropertyGetterName();
1084 if (!GetterName.empty())
1085 addString(ElemDie, dwarf::DW_AT_APPLE_property_getter, GetterName);
1086 StringRef SetterName = Property.getObjCPropertySetterName();
1087 if (!SetterName.empty())
1088 addString(ElemDie, dwarf::DW_AT_APPLE_property_setter, SetterName);
1089 unsigned PropertyAttributes = 0;
1090 if (Property.isReadOnlyObjCProperty())
1091 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_readonly;
1092 if (Property.isReadWriteObjCProperty())
1093 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_readwrite;
1094 if (Property.isAssignObjCProperty())
1095 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_assign;
1096 if (Property.isRetainObjCProperty())
1097 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_retain;
1098 if (Property.isCopyObjCProperty())
1099 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_copy;
1100 if (Property.isNonAtomicObjCProperty())
1101 PropertyAttributes |= dwarf::DW_APPLE_PROPERTY_nonatomic;
1102 if (PropertyAttributes)
1103 addUInt(ElemDie, dwarf::DW_AT_APPLE_property_attribute, None,
1104 PropertyAttributes);
1106 DIEEntry *Entry = getDIEEntry(Element);
1108 Entry = createDIEEntry(ElemDie);
1109 insertDIEEntry(Element, Entry);
1115 if (CTy.isAppleBlockExtension())
1116 addFlag(Buffer, dwarf::DW_AT_APPLE_block);
1118 DICompositeType ContainingType(resolve(CTy.getContainingType()));
1120 addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
1121 *getOrCreateTypeDIE(ContainingType));
1123 if (CTy.isObjcClassComplete())
1124 addFlag(Buffer, dwarf::DW_AT_APPLE_objc_complete_type);
1126 // Add template parameters to a class, structure or union types.
1127 // FIXME: The support isn't in the metadata for this yet.
1128 if (Tag == dwarf::DW_TAG_class_type ||
1129 Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
1130 addTemplateParams(Buffer, CTy.getTemplateParams());
1138 // Add name if not anonymous or intermediate type.
1140 addString(Buffer, dwarf::DW_AT_name, Name);
1142 if (Tag == dwarf::DW_TAG_enumeration_type ||
1143 Tag == dwarf::DW_TAG_class_type || Tag == dwarf::DW_TAG_structure_type ||
1144 Tag == dwarf::DW_TAG_union_type) {
1145 // Add size if non-zero (derived types might be zero-sized.)
1146 // TODO: Do we care about size for enum forward declarations?
1148 addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
1149 else if (!CTy.isForwardDecl())
1150 // Add zero size if it is not a forward declaration.
1151 addUInt(Buffer, dwarf::DW_AT_byte_size, None, 0);
1153 // If we're a forward decl, say so.
1154 if (CTy.isForwardDecl())
1155 addFlag(Buffer, dwarf::DW_AT_declaration);
1157 // Add source line info if available.
1158 if (!CTy.isForwardDecl())
1159 addSourceLine(Buffer, CTy);
1161 // No harm in adding the runtime language to the declaration.
1162 unsigned RLang = CTy.getRunTimeLang();
1164 addUInt(Buffer, dwarf::DW_AT_APPLE_runtime_class, dwarf::DW_FORM_data1,
1169 /// constructTemplateTypeParameterDIE - Construct new DIE for the given
1170 /// DITemplateTypeParameter.
1171 void DwarfUnit::constructTemplateTypeParameterDIE(DIE &Buffer,
1172 DITemplateTypeParameter TP) {
1174 createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
1175 // Add the type if it exists, it could be void and therefore no type.
1177 addType(ParamDIE, resolve(TP.getType()));
1178 if (!TP.getName().empty())
1179 addString(ParamDIE, dwarf::DW_AT_name, TP.getName());
1182 /// constructTemplateValueParameterDIE - Construct new DIE for the given
1183 /// DITemplateValueParameter.
1185 DwarfUnit::constructTemplateValueParameterDIE(DIE &Buffer,
1186 DITemplateValueParameter VP) {
1187 DIE &ParamDIE = createAndAddDIE(VP.getTag(), Buffer);
1189 // Add the type if there is one, template template and template parameter
1190 // packs will not have a type.
1191 if (VP.getTag() == dwarf::DW_TAG_template_value_parameter)
1192 addType(ParamDIE, resolve(VP.getType()));
1193 if (!VP.getName().empty())
1194 addString(ParamDIE, dwarf::DW_AT_name, VP.getName());
1195 if (Metadata *Val = VP.getValue()) {
1196 if (ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(Val))
1197 addConstantValue(ParamDIE, CI, resolve(VP.getType()));
1198 else if (GlobalValue *GV = mdconst::dyn_extract<GlobalValue>(Val)) {
1199 // For declaration non-type template parameters (such as global values and
1201 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
1202 addOpAddress(*Loc, Asm->getSymbol(GV));
1203 // Emit DW_OP_stack_value to use the address as the immediate value of the
1204 // parameter, rather than a pointer to it.
1205 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_stack_value);
1206 addBlock(ParamDIE, dwarf::DW_AT_location, Loc);
1207 } else if (VP.getTag() == dwarf::DW_TAG_GNU_template_template_param) {
1208 assert(isa<MDString>(Val));
1209 addString(ParamDIE, dwarf::DW_AT_GNU_template_name,
1210 cast<MDString>(Val)->getString());
1211 } else if (VP.getTag() == dwarf::DW_TAG_GNU_template_parameter_pack) {
1212 assert(isa<MDNode>(Val));
1213 DIArray A(cast<MDNode>(Val));
1214 addTemplateParams(ParamDIE, A);
1219 /// getOrCreateNameSpace - Create a DIE for DINameSpace.
1220 DIE *DwarfUnit::getOrCreateNameSpace(DINameSpace NS) {
1221 // Construct the context before querying for the existence of the DIE in case
1222 // such construction creates the DIE.
1223 DIE *ContextDIE = getOrCreateContextDIE(NS.getContext());
1225 if (DIE *NDie = getDIE(NS))
1227 DIE &NDie = createAndAddDIE(dwarf::DW_TAG_namespace, *ContextDIE, NS);
1229 StringRef Name = NS.getName();
1231 addString(NDie, dwarf::DW_AT_name, NS.getName());
1233 Name = "(anonymous namespace)";
1234 DD->addAccelNamespace(Name, NDie);
1235 addGlobalName(Name, NDie, NS.getContext());
1236 addSourceLine(NDie, NS);
1240 /// getOrCreateSubprogramDIE - Create new DIE using SP.
1241 DIE *DwarfUnit::getOrCreateSubprogramDIE(DISubprogram SP, bool Minimal) {
1242 // Construct the context before querying for the existence of the DIE in case
1243 // such construction creates the DIE (as is the case for member function
1246 Minimal ? &getUnitDie() : getOrCreateContextDIE(resolve(SP.getContext()));
1248 if (DIE *SPDie = getDIE(SP))
1251 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
1253 // Add subprogram definitions to the CU die directly.
1254 ContextDIE = &getUnitDie();
1255 // Build the decl now to ensure it precedes the definition.
1256 getOrCreateSubprogramDIE(SPDecl);
1260 // DW_TAG_inlined_subroutine may refer to this DIE.
1261 DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
1263 // Stop here and fill this in later, depending on whether or not this
1264 // subprogram turns out to have inlined instances or not.
1265 if (SP.isDefinition())
1268 applySubprogramAttributes(SP, SPDie);
1272 bool DwarfUnit::applySubprogramDefinitionAttributes(DISubprogram SP,
1274 DIE *DeclDie = nullptr;
1275 StringRef DeclLinkageName;
1276 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
1277 DeclDie = getDIE(SPDecl);
1278 assert(DeclDie && "This DIE should've already been constructed when the "
1279 "definition DIE was created in "
1280 "getOrCreateSubprogramDIE");
1281 DeclLinkageName = SPDecl.getLinkageName();
1284 // Add function template parameters.
1285 addTemplateParams(SPDie, SP.getTemplateParams());
1287 // Add the linkage name if we have one and it isn't in the Decl.
1288 StringRef LinkageName = SP.getLinkageName();
1289 assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
1290 LinkageName == DeclLinkageName) &&
1291 "decl has a linkage name and it is different");
1292 if (!LinkageName.empty() && DeclLinkageName.empty())
1293 addString(SPDie, dwarf::DW_AT_MIPS_linkage_name,
1294 GlobalValue::getRealLinkageName(LinkageName));
1299 // Refer to the function declaration where all the other attributes will be
1301 addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
1305 void DwarfUnit::applySubprogramAttributes(DISubprogram SP, DIE &SPDie,
1308 if (applySubprogramDefinitionAttributes(SP, SPDie))
1311 // Constructors and operators for anonymous aggregates do not have names.
1312 if (!SP.getName().empty())
1313 addString(SPDie, dwarf::DW_AT_name, SP.getName());
1315 // Skip the rest of the attributes under -gmlt to save space.
1319 addSourceLine(SPDie, SP);
1321 // Add the prototype if we have a prototype and we have a C like
1323 uint16_t Language = getLanguage();
1324 if (SP.isPrototyped() &&
1325 (Language == dwarf::DW_LANG_C89 || Language == dwarf::DW_LANG_C99 ||
1326 Language == dwarf::DW_LANG_ObjC))
1327 addFlag(SPDie, dwarf::DW_AT_prototyped);
1329 DISubroutineType SPTy = SP.getType();
1330 assert(SPTy.getTag() == dwarf::DW_TAG_subroutine_type &&
1331 "the type of a subprogram should be a subroutine");
1333 DITypeArray Args = SPTy.getTypeArray();
1334 // Add a return type. If this is a type like a C/C++ void type we don't add a
1336 if (resolve(Args.getElement(0)))
1337 addType(SPDie, DIType(resolve(Args.getElement(0))));
1339 unsigned VK = SP.getVirtuality();
1341 addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1, VK);
1342 DIELoc *Block = getDIELoc();
1343 addUInt(*Block, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1344 addUInt(*Block, dwarf::DW_FORM_udata, SP.getVirtualIndex());
1345 addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
1346 ContainingTypeMap.insert(
1347 std::make_pair(&SPDie, resolve(SP.getContainingType())));
1350 if (!SP.isDefinition()) {
1351 addFlag(SPDie, dwarf::DW_AT_declaration);
1353 // Add arguments. Do not add arguments for subprogram definition. They will
1354 // be handled while processing variables.
1355 constructSubprogramArguments(SPDie, Args);
1358 if (SP.isArtificial())
1359 addFlag(SPDie, dwarf::DW_AT_artificial);
1361 if (!SP.isLocalToUnit())
1362 addFlag(SPDie, dwarf::DW_AT_external);
1364 if (SP.isOptimized())
1365 addFlag(SPDie, dwarf::DW_AT_APPLE_optimized);
1367 if (unsigned isa = Asm->getISAEncoding()) {
1368 addUInt(SPDie, dwarf::DW_AT_APPLE_isa, dwarf::DW_FORM_flag, isa);
1371 if (SP.isLValueReference())
1372 addFlag(SPDie, dwarf::DW_AT_reference);
1374 if (SP.isRValueReference())
1375 addFlag(SPDie, dwarf::DW_AT_rvalue_reference);
1377 if (SP.isProtected())
1378 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1379 dwarf::DW_ACCESS_protected);
1380 else if (SP.isPrivate())
1381 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1382 dwarf::DW_ACCESS_private);
1383 else if (SP.isPublic())
1384 addUInt(SPDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1385 dwarf::DW_ACCESS_public);
1387 if (SP.isExplicit())
1388 addFlag(SPDie, dwarf::DW_AT_explicit);
1391 /// constructSubrangeDIE - Construct subrange DIE from DISubrange.
1392 void DwarfUnit::constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy) {
1393 DIE &DW_Subrange = createAndAddDIE(dwarf::DW_TAG_subrange_type, Buffer);
1394 addDIEEntry(DW_Subrange, dwarf::DW_AT_type, *IndexTy);
1396 // The LowerBound value defines the lower bounds which is typically zero for
1397 // C/C++. The Count value is the number of elements. Values are 64 bit. If
1398 // Count == -1 then the array is unbounded and we do not emit
1399 // DW_AT_lower_bound and DW_AT_count attributes.
1400 int64_t LowerBound = SR.getLo();
1401 int64_t DefaultLowerBound = getDefaultLowerBound();
1402 int64_t Count = SR.getCount();
1404 if (DefaultLowerBound == -1 || LowerBound != DefaultLowerBound)
1405 addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, None, LowerBound);
1408 // FIXME: An unbounded array should reference the expression that defines
1410 addUInt(DW_Subrange, dwarf::DW_AT_count, None, Count);
1413 DIE *DwarfUnit::getIndexTyDie() {
1416 // Construct an integer type to use for indexes.
1417 IndexTyDie = &createAndAddDIE(dwarf::DW_TAG_base_type, UnitDie);
1418 addString(*IndexTyDie, dwarf::DW_AT_name, "sizetype");
1419 addUInt(*IndexTyDie, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
1420 addUInt(*IndexTyDie, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
1421 dwarf::DW_ATE_unsigned);
1425 /// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
1426 void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, DICompositeType CTy) {
1428 addFlag(Buffer, dwarf::DW_AT_GNU_vector);
1430 // Emit the element type.
1431 addType(Buffer, resolve(CTy.getTypeDerivedFrom()));
1433 // Get an anonymous type for index type.
1434 // FIXME: This type should be passed down from the front end
1435 // as different languages may have different sizes for indexes.
1436 DIE *IdxTy = getIndexTyDie();
1438 // Add subranges to array type.
1439 DIArray Elements = CTy.getElements();
1440 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1441 DIDescriptor Element = Elements.getElement(i);
1442 if (Element.getTag() == dwarf::DW_TAG_subrange_type)
1443 constructSubrangeDIE(Buffer, DISubrange(Element), IdxTy);
1447 /// constructEnumTypeDIE - Construct an enum type DIE from DICompositeType.
1448 void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, DICompositeType CTy) {
1449 DIArray Elements = CTy.getElements();
1451 // Add enumerators to enumeration type.
1452 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
1453 DIEnumerator Enum(Elements.getElement(i));
1454 if (Enum.isEnumerator()) {
1455 DIE &Enumerator = createAndAddDIE(dwarf::DW_TAG_enumerator, Buffer);
1456 StringRef Name = Enum.getName();
1457 addString(Enumerator, dwarf::DW_AT_name, Name);
1458 int64_t Value = Enum.getEnumValue();
1459 addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
1463 DIType DTy = resolve(CTy.getTypeDerivedFrom());
1465 addType(Buffer, DTy);
1466 addFlag(Buffer, dwarf::DW_AT_enum_class);
1470 /// constructContainingTypeDIEs - Construct DIEs for types that contain
1472 void DwarfUnit::constructContainingTypeDIEs() {
1473 for (DenseMap<DIE *, const MDNode *>::iterator CI = ContainingTypeMap.begin(),
1474 CE = ContainingTypeMap.end();
1476 DIE &SPDie = *CI->first;
1477 DIDescriptor D(CI->second);
1480 DIE *NDie = getDIE(D);
1483 addDIEEntry(SPDie, dwarf::DW_AT_containing_type, *NDie);
1487 /// constructMemberDIE - Construct member DIE from DIDerivedType.
1488 void DwarfUnit::constructMemberDIE(DIE &Buffer, DIDerivedType DT) {
1489 DIE &MemberDie = createAndAddDIE(DT.getTag(), Buffer);
1490 StringRef Name = DT.getName();
1492 addString(MemberDie, dwarf::DW_AT_name, Name);
1494 addType(MemberDie, resolve(DT.getTypeDerivedFrom()));
1496 addSourceLine(MemberDie, DT);
1498 if (DT.getTag() == dwarf::DW_TAG_inheritance && DT.isVirtual()) {
1500 // For C++, virtual base classes are not at fixed offset. Use following
1501 // expression to extract appropriate offset from vtable.
1502 // BaseAddr = ObAddr + *((*ObAddr) - Offset)
1504 DIELoc *VBaseLocationDie = new (DIEValueAllocator) DIELoc();
1505 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
1506 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1507 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
1508 addUInt(*VBaseLocationDie, dwarf::DW_FORM_udata, DT.getOffsetInBits());
1509 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
1510 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
1511 addUInt(*VBaseLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
1513 addBlock(MemberDie, dwarf::DW_AT_data_member_location, VBaseLocationDie);
1515 uint64_t Size = DT.getSizeInBits();
1516 uint64_t FieldSize = getBaseTypeSize(DD, DT);
1517 uint64_t OffsetInBytes;
1519 if (Size != FieldSize) {
1520 // Handle bitfield, assume bytes are 8 bits.
1521 addUInt(MemberDie, dwarf::DW_AT_byte_size, None, FieldSize/8);
1522 addUInt(MemberDie, dwarf::DW_AT_bit_size, None, Size);
1524 uint64_t Offset = DT.getOffsetInBits();
1525 uint64_t AlignMask = ~(DT.getAlignInBits() - 1);
1526 uint64_t HiMark = (Offset + FieldSize) & AlignMask;
1527 uint64_t FieldOffset = (HiMark - FieldSize);
1528 Offset -= FieldOffset;
1530 // Maybe we need to work from the other end.
1531 if (Asm->getDataLayout().isLittleEndian())
1532 Offset = FieldSize - (Offset + Size);
1533 addUInt(MemberDie, dwarf::DW_AT_bit_offset, None, Offset);
1535 // Here DW_AT_data_member_location points to the anonymous
1536 // field that includes this bit field.
1537 OffsetInBytes = FieldOffset >> 3;
1539 // This is not a bitfield.
1540 OffsetInBytes = DT.getOffsetInBits() >> 3;
1542 if (DD->getDwarfVersion() <= 2) {
1543 DIELoc *MemLocationDie = new (DIEValueAllocator) DIELoc();
1544 addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
1545 addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes);
1546 addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie);
1548 addUInt(MemberDie, dwarf::DW_AT_data_member_location, None,
1552 if (DT.isProtected())
1553 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1554 dwarf::DW_ACCESS_protected);
1555 else if (DT.isPrivate())
1556 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1557 dwarf::DW_ACCESS_private);
1558 // Otherwise C++ member and base classes are considered public.
1559 else if (DT.isPublic())
1560 addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1561 dwarf::DW_ACCESS_public);
1563 addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_data1,
1564 dwarf::DW_VIRTUALITY_virtual);
1566 // Objective-C properties.
1567 if (MDNode *PNode = DT.getObjCProperty())
1568 if (DIEEntry *PropertyDie = getDIEEntry(PNode))
1569 MemberDie.addValue(dwarf::DW_AT_APPLE_property, dwarf::DW_FORM_ref4,
1572 if (DT.isArtificial())
1573 addFlag(MemberDie, dwarf::DW_AT_artificial);
1576 /// getOrCreateStaticMemberDIE - Create new DIE for C++ static member.
1577 DIE *DwarfUnit::getOrCreateStaticMemberDIE(DIDerivedType DT) {
1581 // Construct the context before querying for the existence of the DIE in case
1582 // such construction creates the DIE.
1583 DIE *ContextDIE = getOrCreateContextDIE(resolve(DT.getContext()));
1584 assert(dwarf::isType(ContextDIE->getTag()) &&
1585 "Static member should belong to a type.");
1587 if (DIE *StaticMemberDIE = getDIE(DT))
1588 return StaticMemberDIE;
1590 DIE &StaticMemberDIE = createAndAddDIE(DT.getTag(), *ContextDIE, DT);
1592 DIType Ty = resolve(DT.getTypeDerivedFrom());
1594 addString(StaticMemberDIE, dwarf::DW_AT_name, DT.getName());
1595 addType(StaticMemberDIE, Ty);
1596 addSourceLine(StaticMemberDIE, DT);
1597 addFlag(StaticMemberDIE, dwarf::DW_AT_external);
1598 addFlag(StaticMemberDIE, dwarf::DW_AT_declaration);
1600 // FIXME: We could omit private if the parent is a class_type, and
1601 // public if the parent is something else.
1602 if (DT.isProtected())
1603 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1604 dwarf::DW_ACCESS_protected);
1605 else if (DT.isPrivate())
1606 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1607 dwarf::DW_ACCESS_private);
1608 else if (DT.isPublic())
1609 addUInt(StaticMemberDIE, dwarf::DW_AT_accessibility, dwarf::DW_FORM_data1,
1610 dwarf::DW_ACCESS_public);
1612 if (const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(DT.getConstant()))
1613 addConstantValue(StaticMemberDIE, CI, Ty);
1614 if (const ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(DT.getConstant()))
1615 addConstantFPValue(StaticMemberDIE, CFP);
1617 return &StaticMemberDIE;
1620 void DwarfUnit::emitHeader(const MCSymbol *ASectionSym) const {
1621 // Emit size of content not including length itself
1622 Asm->OutStreamer.AddComment("Length of Unit");
1623 Asm->EmitInt32(getHeaderSize() + UnitDie.getSize());
1625 Asm->OutStreamer.AddComment("DWARF version number");
1626 Asm->EmitInt16(DD->getDwarfVersion());
1627 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section");
1628 // We share one abbreviations table across all units so it's always at the
1629 // start of the section. Use a relocatable offset where needed to ensure
1630 // linking doesn't invalidate that offset.
1632 Asm->EmitSectionOffset(ASectionSym, ASectionSym);
1634 // Use a constant value when no symbol is provided.
1636 Asm->OutStreamer.AddComment("Address Size (in bytes)");
1637 Asm->EmitInt8(Asm->getDataLayout().getPointerSize());
1640 void DwarfUnit::initSection(const MCSection *Section) {
1641 assert(!this->Section);
1642 this->Section = Section;
1645 void DwarfTypeUnit::emitHeader(const MCSymbol *ASectionSym) const {
1646 DwarfUnit::emitHeader(ASectionSym);
1647 Asm->OutStreamer.AddComment("Type Signature");
1648 Asm->OutStreamer.EmitIntValue(TypeSignature, sizeof(TypeSignature));
1649 Asm->OutStreamer.AddComment("Type DIE Offset");
1650 // In a skeleton type unit there is no type DIE so emit a zero offset.
1651 Asm->OutStreamer.EmitIntValue(Ty ? Ty->getOffset() : 0,
1652 sizeof(Ty->getOffset()));
1655 bool DwarfTypeUnit::isDwoUnit() const {
1656 // Since there are no skeleton type units, all type units are dwo type units
1657 // when split DWARF is being used.
1658 return DD->useSplitDwarf();