1 //===--- lib/CodeGen/DIE.cpp - DWARF Info Entries -------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Data structures for DWARF info entries.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "DIE.h"
15 #include "DwarfDebug.h"
16 #include "DwarfUnit.h"
17 #include "llvm/ADT/Twine.h"
18 #include "llvm/CodeGen/AsmPrinter.h"
19 #include "llvm/IR/DataLayout.h"
20 #include "llvm/MC/MCAsmInfo.h"
21 #include "llvm/MC/MCStreamer.h"
22 #include "llvm/MC/MCSymbol.h"
23 #include "llvm/Support/Debug.h"
24 #include "llvm/Support/ErrorHandling.h"
25 #include "llvm/Support/Format.h"
26 #include "llvm/Support/FormattedStream.h"
27 #include "llvm/Support/MD5.h"
28 using namespace llvm;
29 
30 //===----------------------------------------------------------------------===//
31 // DIEAbbrevData Implementation
32 //===----------------------------------------------------------------------===//
33 
34 /// Profile - Used to gather unique data for the abbreviation folding set.
35 ///
36 void DIEAbbrevData::Profile(FoldingSetNodeID &ID) const {
37   // Explicitly cast to an integer type for which FoldingSetNodeID has
38   // overloads.  Otherwise MSVC 2010 thinks this call is ambiguous.
39   ID.AddInteger(unsigned(Attribute));
40   ID.AddInteger(unsigned(Form));
41 }
42 
43 //===----------------------------------------------------------------------===//
44 // DIEAbbrev Implementation
45 //===----------------------------------------------------------------------===//
46 
47 /// Profile - Used to gather unique data for the abbreviation folding set.
48 ///
49 void DIEAbbrev::Profile(FoldingSetNodeID &ID) const {
50   ID.AddInteger(unsigned(Tag));
51   ID.AddInteger(ChildrenFlag);
52 
53   // For each attribute description.
54   for (unsigned i = 0, N = Data.size(); i < N; ++i)
55     Data[i].Profile(ID);
56 }
57 
58 /// Emit - Print the abbreviation using the specified asm printer.
59 ///
60 void DIEAbbrev::Emit(AsmPrinter *AP) const {
61   // Emit its Dwarf tag type.
62   AP->EmitULEB128(Tag, dwarf::TagString(Tag));
63 
64   // Emit whether it has children DIEs.
65   AP->EmitULEB128(ChildrenFlag, dwarf::ChildrenString(ChildrenFlag));
66 
67   // For each attribute description.
68   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
69     const DIEAbbrevData &AttrData = Data[i];
70 
71     // Emit attribute type.
72     AP->EmitULEB128(AttrData.getAttribute(),
73                     dwarf::AttributeString(AttrData.getAttribute()));
74 
75     // Emit form type.
76     AP->EmitULEB128(AttrData.getForm(),
77                     dwarf::FormEncodingString(AttrData.getForm()));
78   }
79 
80   // Mark end of abbreviation.
81   AP->EmitULEB128(0, "EOM(1)");
82   AP->EmitULEB128(0, "EOM(2)");
83 }
84 
85 #ifndef NDEBUG
86 void DIEAbbrev::print(raw_ostream &O) {
87   O << "Abbreviation @"
88     << format("0x%lx", (long)(intptr_t)this)
89     << "  "
90     << dwarf::TagString(Tag)
91     << " "
92     << dwarf::ChildrenString(ChildrenFlag)
93     << '\n';
94 
95   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
96     O << "  "
97       << dwarf::AttributeString(Data[i].getAttribute())
98       << "  "
99       << dwarf::FormEncodingString(Data[i].getForm())
100       << '\n';
101   }
102 }
103 void DIEAbbrev::dump() { print(dbgs()); }
104 #endif
105 
106 //===----------------------------------------------------------------------===//
107 // DIE Implementation
108 //===----------------------------------------------------------------------===//
109 
110 DIE::~DIE() {
111   for (unsigned i = 0, N = Children.size(); i < N; ++i)
112     delete Children[i];
113 }
114 
115 /// Climb up the parent chain to get the unit DIE to which this DIE
116 /// belongs.
117 const DIE *DIE::getUnit() const {
118   const DIE *Cu = getUnitOrNull();
119   assert(Cu && "We should not have orphaned DIEs.");
120   return Cu;
121 }
122 
123 /// Climb up the parent chain to get the unit DIE this DIE belongs
124 /// to. Return NULL if DIE is not added to an owner yet.
125 const DIE *DIE::getUnitOrNull() const {
126   const DIE *p = this;
127   while (p) {
128     if (p->getTag() == dwarf::DW_TAG_compile_unit ||
129         p->getTag() == dwarf::DW_TAG_type_unit)
130       return p;
131     p = p->getParent();
132   }
133   return NULL;
134 }
135 
136 DIEValue *DIE::findAttribute(uint16_t Attribute) const {
137   const SmallVectorImpl<DIEValue *> &Values = getValues();
138   const DIEAbbrev &Abbrevs = getAbbrev();
139 
140   // Iterate through all the attributes until we find the one we're
141   // looking for, if we can't find it return NULL.
142   for (size_t i = 0; i < Values.size(); ++i)
143     if (Abbrevs.getData()[i].getAttribute() == Attribute)
144       return Values[i];
145   return NULL;
146 }
147 
148 #ifndef NDEBUG
149 void DIE::print(raw_ostream &O, unsigned IndentCount) const {
150   const std::string Indent(IndentCount, ' ');
151   bool isBlock = Abbrev.getTag() == 0;
152 
153   if (!isBlock) {
154     O << Indent
155       << "Die: "
156       << format("0x%lx", (long)(intptr_t)this)
157       << ", Offset: " << Offset
158       << ", Size: " << Size << "\n";
159 
160     O << Indent
161       << dwarf::TagString(Abbrev.getTag())
162       << " "
163       << dwarf::ChildrenString(Abbrev.getChildrenFlag()) << "\n";
164   } else {
165     O << "Size: " << Size << "\n";
166   }
167 
168   const SmallVectorImpl<DIEAbbrevData> &Data = Abbrev.getData();
169 
170   IndentCount += 2;
171   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
172     O << Indent;
173 
174     if (!isBlock)
175       O << dwarf::AttributeString(Data[i].getAttribute());
176     else
177       O << "Blk[" << i << "]";
178 
179     O <<  "  "
180       << dwarf::FormEncodingString(Data[i].getForm())
181       << " ";
182     Values[i]->print(O);
183     O << "\n";
184   }
185   IndentCount -= 2;
186 
187   for (unsigned j = 0, M = Children.size(); j < M; ++j) {
188     Children[j]->print(O, IndentCount+4);
189   }
190 
191   if (!isBlock) O << "\n";
192 }
193 
194 void DIE::dump() {
195   print(dbgs());
196 }
197 #endif
198 
199 void DIEValue::anchor() { }
200 
201 #ifndef NDEBUG
202 void DIEValue::dump() const {
203   print(dbgs());
204 }
205 #endif
206 
207 //===----------------------------------------------------------------------===//
208 // DIEInteger Implementation
209 //===----------------------------------------------------------------------===//
210 
211 /// EmitValue - Emit integer of appropriate size.
212 ///
213 void DIEInteger::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
214   unsigned Size = ~0U;
215   switch (Form) {
216   case dwarf::DW_FORM_flag_present:
217     // Emit something to keep the lines and comments in sync.
218     // FIXME: Is there a better way to do this?
219     Asm->OutStreamer.AddBlankLine();
220     return;
221   case dwarf::DW_FORM_flag:  // Fall thru
222   case dwarf::DW_FORM_ref1:  // Fall thru
223   case dwarf::DW_FORM_data1: Size = 1; break;
224   case dwarf::DW_FORM_ref2:  // Fall thru
225   case dwarf::DW_FORM_data2: Size = 2; break;
226   case dwarf::DW_FORM_sec_offset: // Fall thru
227   case dwarf::DW_FORM_ref4:  // Fall thru
228   case dwarf::DW_FORM_data4: Size = 4; break;
229   case dwarf::DW_FORM_ref8:  // Fall thru
230   case dwarf::DW_FORM_ref_sig8:  // Fall thru
231   case dwarf::DW_FORM_data8: Size = 8; break;
232   case dwarf::DW_FORM_GNU_str_index: Asm->EmitULEB128(Integer); return;
233   case dwarf::DW_FORM_GNU_addr_index: Asm->EmitULEB128(Integer); return;
234   case dwarf::DW_FORM_udata: Asm->EmitULEB128(Integer); return;
235   case dwarf::DW_FORM_sdata: Asm->EmitSLEB128(Integer); return;
236   case dwarf::DW_FORM_addr:
237     Size = Asm->getDataLayout().getPointerSize(); break;
238   default: llvm_unreachable("DIE Value form not supported yet");
239   }
240   Asm->OutStreamer.EmitIntValue(Integer, Size);
241 }
242 
243 /// SizeOf - Determine size of integer value in bytes.
244 ///
245 unsigned DIEInteger::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
246   switch (Form) {
247   case dwarf::DW_FORM_flag_present: return 0;
248   case dwarf::DW_FORM_flag:  // Fall thru
249   case dwarf::DW_FORM_ref1:  // Fall thru
250   case dwarf::DW_FORM_data1: return sizeof(int8_t);
251   case dwarf::DW_FORM_ref2:  // Fall thru
252   case dwarf::DW_FORM_data2: return sizeof(int16_t);
253   case dwarf::DW_FORM_sec_offset: // Fall thru
254   case dwarf::DW_FORM_ref4:  // Fall thru
255   case dwarf::DW_FORM_data4: return sizeof(int32_t);
256   case dwarf::DW_FORM_ref8:  // Fall thru
257   case dwarf::DW_FORM_ref_sig8:  // Fall thru
258   case dwarf::DW_FORM_data8: return sizeof(int64_t);
259   case dwarf::DW_FORM_GNU_str_index: return MCAsmInfo::getULEB128Size(Integer);
260   case dwarf::DW_FORM_GNU_addr_index: return MCAsmInfo::getULEB128Size(Integer);
261   case dwarf::DW_FORM_udata: return MCAsmInfo::getULEB128Size(Integer);
262   case dwarf::DW_FORM_sdata: return MCAsmInfo::getSLEB128Size(Integer);
263   case dwarf::DW_FORM_addr:  return AP->getDataLayout().getPointerSize();
264   default: llvm_unreachable("DIE Value form not supported yet");
265   }
266 }
267 
268 #ifndef NDEBUG
269 void DIEInteger::print(raw_ostream &O) const {
270   O << "Int: " << (int64_t)Integer << "  0x";
271   O.write_hex(Integer);
272 }
273 #endif
274 
275 //===----------------------------------------------------------------------===//
276 // DIEExpr Implementation
277 //===----------------------------------------------------------------------===//
278 
279 /// EmitValue - Emit expression value.
280 ///
281 void DIEExpr::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
282   AP->OutStreamer.EmitValue(Expr, SizeOf(AP, Form));
283 }
284 
285 /// SizeOf - Determine size of expression value in bytes.
286 ///
287 unsigned DIEExpr::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
288   if (Form == dwarf::DW_FORM_data4) return 4;
289   if (Form == dwarf::DW_FORM_sec_offset) return 4;
290   if (Form == dwarf::DW_FORM_strp) return 4;
291   return AP->getDataLayout().getPointerSize();
292 }
293 
294 #ifndef NDEBUG
295 void DIEExpr::print(raw_ostream &O) const {
296   O << "Expr: ";
297   Expr->print(O);
298 }
299 #endif
300 
301 //===----------------------------------------------------------------------===//
302 // DIELabel Implementation
303 //===----------------------------------------------------------------------===//
304 
305 /// EmitValue - Emit label value.
306 ///
307 void DIELabel::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
308   AP->EmitLabelReference(Label, SizeOf(AP, Form),
309                          Form == dwarf::DW_FORM_strp ||
310                              Form == dwarf::DW_FORM_sec_offset ||
311                              Form == dwarf::DW_FORM_ref_addr);
312 }
313 
314 /// SizeOf - Determine size of label value in bytes.
315 ///
316 unsigned DIELabel::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
317   if (Form == dwarf::DW_FORM_data4) return 4;
318   if (Form == dwarf::DW_FORM_sec_offset) return 4;
319   if (Form == dwarf::DW_FORM_strp) return 4;
320   return AP->getDataLayout().getPointerSize();
321 }
322 
323 #ifndef NDEBUG
324 void DIELabel::print(raw_ostream &O) const {
325   O << "Lbl: " << Label->getName();
326 }
327 #endif
328 
329 //===----------------------------------------------------------------------===//
330 // DIEDelta Implementation
331 //===----------------------------------------------------------------------===//
332 
333 /// EmitValue - Emit delta value.
334 ///
335 void DIEDelta::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
336   AP->EmitLabelDifference(LabelHi, LabelLo, SizeOf(AP, Form));
337 }
338 
339 /// SizeOf - Determine size of delta value in bytes.
340 ///
341 unsigned DIEDelta::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
342   if (Form == dwarf::DW_FORM_data4) return 4;
343   if (Form == dwarf::DW_FORM_sec_offset) return 4;
344   if (Form == dwarf::DW_FORM_strp) return 4;
345   return AP->getDataLayout().getPointerSize();
346 }
347 
348 #ifndef NDEBUG
349 void DIEDelta::print(raw_ostream &O) const {
350   O << "Del: " << LabelHi->getName() << "-" << LabelLo->getName();
351 }
352 #endif
353 
354 //===----------------------------------------------------------------------===//
355 // DIEString Implementation
356 //===----------------------------------------------------------------------===//
357 
358 /// EmitValue - Emit string value.
359 ///
360 void DIEString::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
361   Access->EmitValue(AP, Form);
362 }
363 
364 /// SizeOf - Determine size of delta value in bytes.
365 ///
366 unsigned DIEString::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
367   return Access->SizeOf(AP, Form);
368 }
369 
370 #ifndef NDEBUG
371 void DIEString::print(raw_ostream &O) const {
372   O << "String: " << Str << "\tSymbol: ";
373   Access->print(O);
374 }
375 #endif
376 
377 //===----------------------------------------------------------------------===//
378 // DIEEntry Implementation
379 //===----------------------------------------------------------------------===//
380 
381 /// EmitValue - Emit debug information entry offset.
382 ///
383 void DIEEntry::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
384   AP->EmitInt32(Entry->getOffset());
385 }
386 
387 unsigned DIEEntry::getRefAddrSize(AsmPrinter *AP) {
388   // DWARF4: References that use the attribute form DW_FORM_ref_addr are
389   // specified to be four bytes in the DWARF 32-bit format and eight bytes
390   // in the DWARF 64-bit format, while DWARF Version 2 specifies that such
391   // references have the same size as an address on the target system.
392   const DwarfDebug *DD = AP->getDwarfDebug();
393   assert(DD && "Expected Dwarf Debug info to be available");
394   if (DD->getDwarfVersion() == 2)
395     return AP->getDataLayout().getPointerSize();
396   return sizeof(int32_t);
397 }
398 
399 #ifndef NDEBUG
400 void DIEEntry::print(raw_ostream &O) const {
401   O << format("Die: 0x%lx", (long)(intptr_t)Entry);
402 }
403 #endif
404 
405 //===----------------------------------------------------------------------===//
406 // DIETypeSignature Implementation
407 //===----------------------------------------------------------------------===//
408 void DIETypeSignature::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
409   assert(Form == dwarf::DW_FORM_ref_sig8);
410   Asm->OutStreamer.EmitIntValue(Unit.getTypeSignature(), 8);
411 }
412 
413 #ifndef NDEBUG
414 void DIETypeSignature::print(raw_ostream &O) const {
415   O << format("Type Unit: 0x%lx", Unit.getTypeSignature());
416 }
417 
418 void DIETypeSignature::dump() const { print(dbgs()); }
419 #endif
420 
421 //===----------------------------------------------------------------------===//
422 // DIEBlock Implementation
423 //===----------------------------------------------------------------------===//
424 
425 /// ComputeSize - calculate the size of the block.
426 ///
427 unsigned DIEBlock::ComputeSize(AsmPrinter *AP) {
428   if (!Size) {
429     const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
430     for (unsigned i = 0, N = Values.size(); i < N; ++i)
431       Size += Values[i]->SizeOf(AP, AbbrevData[i].getForm());
432   }
433 
434   return Size;
435 }
436 
437 /// EmitValue - Emit block data.
438 ///
439 void DIEBlock::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
440   switch (Form) {
441   default: llvm_unreachable("Improper form for block");
442   case dwarf::DW_FORM_block1: Asm->EmitInt8(Size);    break;
443   case dwarf::DW_FORM_block2: Asm->EmitInt16(Size);   break;
444   case dwarf::DW_FORM_block4: Asm->EmitInt32(Size);   break;
445   case dwarf::DW_FORM_block:  Asm->EmitULEB128(Size); break;
446   }
447 
448   const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
449   for (unsigned i = 0, N = Values.size(); i < N; ++i)
450     Values[i]->EmitValue(Asm, AbbrevData[i].getForm());
451 }
452 
453 /// SizeOf - Determine size of block data in bytes.
454 ///
455 unsigned DIEBlock::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
456   switch (Form) {
457   case dwarf::DW_FORM_block1: return Size + sizeof(int8_t);
458   case dwarf::DW_FORM_block2: return Size + sizeof(int16_t);
459   case dwarf::DW_FORM_block4: return Size + sizeof(int32_t);
460   case dwarf::DW_FORM_block:  return Size + MCAsmInfo::getULEB128Size(Size);
461   default: llvm_unreachable("Improper form for block");
462   }
463 }
464 
465 #ifndef NDEBUG
466 void DIEBlock::print(raw_ostream &O) const {
467   O << "Blk: ";
468   DIE::print(O, 5);
469 }
470 #endif
471