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/Allocator.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Support/Format.h"
27 #include "llvm/Support/FormattedStream.h"
28 #include "llvm/Support/MD5.h"
29 using namespace llvm;
30 
31 //===----------------------------------------------------------------------===//
32 // DIEAbbrevData Implementation
33 //===----------------------------------------------------------------------===//
34 
35 /// Profile - Used to gather unique data for the abbreviation folding set.
36 ///
37 void DIEAbbrevData::Profile(FoldingSetNodeID &ID) const {
38   // Explicitly cast to an integer type for which FoldingSetNodeID has
39   // overloads.  Otherwise MSVC 2010 thinks this call is ambiguous.
40   ID.AddInteger(unsigned(Attribute));
41   ID.AddInteger(unsigned(Form));
42 }
43 
44 //===----------------------------------------------------------------------===//
45 // DIEAbbrev Implementation
46 //===----------------------------------------------------------------------===//
47 
48 /// Profile - Used to gather unique data for the abbreviation folding set.
49 ///
50 void DIEAbbrev::Profile(FoldingSetNodeID &ID) const {
51   ID.AddInteger(unsigned(Tag));
52   ID.AddInteger(ChildrenFlag);
53 
54   // For each attribute description.
55   for (unsigned i = 0, N = Data.size(); i < N; ++i)
56     Data[i].Profile(ID);
57 }
58 
59 /// Emit - Print the abbreviation using the specified asm printer.
60 ///
61 void DIEAbbrev::Emit(AsmPrinter *AP) const {
62   // Emit its Dwarf tag type.
63   AP->EmitULEB128(Tag, dwarf::TagString(Tag));
64 
65   // Emit whether it has children DIEs.
66   AP->EmitULEB128(ChildrenFlag, dwarf::ChildrenString(ChildrenFlag));
67 
68   // For each attribute description.
69   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
70     const DIEAbbrevData &AttrData = Data[i];
71 
72     // Emit attribute type.
73     AP->EmitULEB128(AttrData.getAttribute(),
74                     dwarf::AttributeString(AttrData.getAttribute()));
75 
76     // Emit form type.
77     AP->EmitULEB128(AttrData.getForm(),
78                     dwarf::FormEncodingString(AttrData.getForm()));
79   }
80 
81   // Mark end of abbreviation.
82   AP->EmitULEB128(0, "EOM(1)");
83   AP->EmitULEB128(0, "EOM(2)");
84 }
85 
86 #ifndef NDEBUG
87 void DIEAbbrev::print(raw_ostream &O) {
88   O << "Abbreviation @"
89     << format("0x%lx", (long)(intptr_t)this)
90     << "  "
91     << dwarf::TagString(Tag)
92     << " "
93     << dwarf::ChildrenString(ChildrenFlag)
94     << '\n';
95 
96   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
97     O << "  "
98       << dwarf::AttributeString(Data[i].getAttribute())
99       << "  "
100       << dwarf::FormEncodingString(Data[i].getForm())
101       << '\n';
102   }
103 }
104 void DIEAbbrev::dump() { print(dbgs()); }
105 #endif
106 
107 //===----------------------------------------------------------------------===//
108 // DIE Implementation
109 //===----------------------------------------------------------------------===//
110 
111 DIE::~DIE() {
112   for (unsigned i = 0, N = Children.size(); i < N; ++i)
113     delete Children[i];
114 }
115 
116 /// Climb up the parent chain to get the unit DIE to which this DIE
117 /// belongs.
118 const DIE *DIE::getUnit() const {
119   const DIE *Cu = getUnitOrNull();
120   assert(Cu && "We should not have orphaned DIEs.");
121   return Cu;
122 }
123 
124 /// Climb up the parent chain to get the unit DIE this DIE belongs
125 /// to. Return NULL if DIE is not added to an owner yet.
126 const DIE *DIE::getUnitOrNull() const {
127   const DIE *p = this;
128   while (p) {
129     if (p->getTag() == dwarf::DW_TAG_compile_unit ||
130         p->getTag() == dwarf::DW_TAG_type_unit)
131       return p;
132     p = p->getParent();
133   }
134   return NULL;
135 }
136 
137 DIEValue *DIE::findAttribute(uint16_t Attribute) const {
138   const SmallVectorImpl<DIEValue *> &Values = getValues();
139   const DIEAbbrev &Abbrevs = getAbbrev();
140 
141   // Iterate through all the attributes until we find the one we're
142   // looking for, if we can't find it return NULL.
143   for (size_t i = 0; i < Values.size(); ++i)
144     if (Abbrevs.getData()[i].getAttribute() == Attribute)
145       return Values[i];
146   return NULL;
147 }
148 
149 #ifndef NDEBUG
150 void DIE::print(raw_ostream &O, unsigned IndentCount) const {
151   const std::string Indent(IndentCount, ' ');
152   bool isBlock = Abbrev.getTag() == 0;
153 
154   if (!isBlock) {
155     O << Indent
156       << "Die: "
157       << format("0x%lx", (long)(intptr_t)this)
158       << ", Offset: " << Offset
159       << ", Size: " << Size << "\n";
160 
161     O << Indent
162       << dwarf::TagString(Abbrev.getTag())
163       << " "
164       << dwarf::ChildrenString(Abbrev.getChildrenFlag()) << "\n";
165   } else {
166     O << "Size: " << Size << "\n";
167   }
168 
169   const SmallVectorImpl<DIEAbbrevData> &Data = Abbrev.getData();
170 
171   IndentCount += 2;
172   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
173     O << Indent;
174 
175     if (!isBlock)
176       O << dwarf::AttributeString(Data[i].getAttribute());
177     else
178       O << "Blk[" << i << "]";
179 
180     O <<  "  "
181       << dwarf::FormEncodingString(Data[i].getForm())
182       << " ";
183     Values[i]->print(O);
184     O << "\n";
185   }
186   IndentCount -= 2;
187 
188   for (unsigned j = 0, M = Children.size(); j < M; ++j) {
189     Children[j]->print(O, IndentCount+4);
190   }
191 
192   if (!isBlock) O << "\n";
193 }
194 
195 void DIE::dump() {
196   print(dbgs());
197 }
198 #endif
199 
200 void DIEValue::anchor() { }
201 
202 #ifndef NDEBUG
203 void DIEValue::dump() const {
204   print(dbgs());
205 }
206 #endif
207 
208 //===----------------------------------------------------------------------===//
209 // DIEInteger Implementation
210 //===----------------------------------------------------------------------===//
211 
212 /// EmitValue - Emit integer of appropriate size.
213 ///
214 void DIEInteger::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
215   unsigned Size = ~0U;
216   switch (Form) {
217   case dwarf::DW_FORM_flag_present:
218     // Emit something to keep the lines and comments in sync.
219     // FIXME: Is there a better way to do this?
220     if (Asm->OutStreamer.hasRawTextSupport())
221       Asm->OutStreamer.EmitRawText("");
222     return;
223   case dwarf::DW_FORM_flag:  // Fall thru
224   case dwarf::DW_FORM_ref1:  // Fall thru
225   case dwarf::DW_FORM_data1: Size = 1; break;
226   case dwarf::DW_FORM_ref2:  // Fall thru
227   case dwarf::DW_FORM_data2: Size = 2; break;
228   case dwarf::DW_FORM_sec_offset: // Fall thru
229   case dwarf::DW_FORM_ref4:  // Fall thru
230   case dwarf::DW_FORM_data4: Size = 4; break;
231   case dwarf::DW_FORM_ref8:  // Fall thru
232   case dwarf::DW_FORM_ref_sig8:  // Fall thru
233   case dwarf::DW_FORM_data8: Size = 8; break;
234   case dwarf::DW_FORM_GNU_str_index: Asm->EmitULEB128(Integer); return;
235   case dwarf::DW_FORM_GNU_addr_index: Asm->EmitULEB128(Integer); return;
236   case dwarf::DW_FORM_udata: Asm->EmitULEB128(Integer); return;
237   case dwarf::DW_FORM_sdata: Asm->EmitSLEB128(Integer); return;
238   case dwarf::DW_FORM_addr:
239     Size = Asm->getDataLayout().getPointerSize(); break;
240   default: llvm_unreachable("DIE Value form not supported yet");
241   }
242   Asm->OutStreamer.EmitIntValue(Integer, Size);
243 }
244 
245 /// SizeOf - Determine size of integer value in bytes.
246 ///
247 unsigned DIEInteger::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
248   switch (Form) {
249   case dwarf::DW_FORM_flag_present: return 0;
250   case dwarf::DW_FORM_flag:  // Fall thru
251   case dwarf::DW_FORM_ref1:  // Fall thru
252   case dwarf::DW_FORM_data1: return sizeof(int8_t);
253   case dwarf::DW_FORM_ref2:  // Fall thru
254   case dwarf::DW_FORM_data2: return sizeof(int16_t);
255   case dwarf::DW_FORM_sec_offset: // Fall thru
256   case dwarf::DW_FORM_ref4:  // Fall thru
257   case dwarf::DW_FORM_data4: return sizeof(int32_t);
258   case dwarf::DW_FORM_ref8:  // Fall thru
259   case dwarf::DW_FORM_ref_sig8:  // Fall thru
260   case dwarf::DW_FORM_data8: return sizeof(int64_t);
261   case dwarf::DW_FORM_GNU_str_index: return MCAsmInfo::getULEB128Size(Integer);
262   case dwarf::DW_FORM_GNU_addr_index: return MCAsmInfo::getULEB128Size(Integer);
263   case dwarf::DW_FORM_udata: return MCAsmInfo::getULEB128Size(Integer);
264   case dwarf::DW_FORM_sdata: return MCAsmInfo::getSLEB128Size(Integer);
265   case dwarf::DW_FORM_addr:  return AP->getDataLayout().getPointerSize();
266   default: llvm_unreachable("DIE Value form not supported yet");
267   }
268 }
269 
270 #ifndef NDEBUG
271 void DIEInteger::print(raw_ostream &O) const {
272   O << "Int: " << (int64_t)Integer << "  0x";
273   O.write_hex(Integer);
274 }
275 #endif
276 
277 //===----------------------------------------------------------------------===//
278 // DIEExpr Implementation
279 //===----------------------------------------------------------------------===//
280 
281 /// EmitValue - Emit expression value.
282 ///
283 void DIEExpr::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
284   AP->OutStreamer.EmitValue(Expr, SizeOf(AP, Form));
285 }
286 
287 /// SizeOf - Determine size of expression value in bytes.
288 ///
289 unsigned DIEExpr::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
290   if (Form == dwarf::DW_FORM_data4) return 4;
291   if (Form == dwarf::DW_FORM_sec_offset) return 4;
292   if (Form == dwarf::DW_FORM_strp) return 4;
293   return AP->getDataLayout().getPointerSize();
294 }
295 
296 #ifndef NDEBUG
297 void DIEExpr::print(raw_ostream &O) const {
298   O << "Expr: ";
299   Expr->print(O);
300 }
301 #endif
302 
303 //===----------------------------------------------------------------------===//
304 // DIELabel Implementation
305 //===----------------------------------------------------------------------===//
306 
307 /// EmitValue - Emit label value.
308 ///
309 void DIELabel::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
310   AP->EmitLabelReference(Label, SizeOf(AP, Form),
311                          Form == dwarf::DW_FORM_strp ||
312                              Form == dwarf::DW_FORM_sec_offset ||
313                              Form == dwarf::DW_FORM_ref_addr);
314 }
315 
316 /// SizeOf - Determine size of label value in bytes.
317 ///
318 unsigned DIELabel::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
319   if (Form == dwarf::DW_FORM_data4) return 4;
320   if (Form == dwarf::DW_FORM_sec_offset) return 4;
321   if (Form == dwarf::DW_FORM_strp) return 4;
322   return AP->getDataLayout().getPointerSize();
323 }
324 
325 #ifndef NDEBUG
326 void DIELabel::print(raw_ostream &O) const {
327   O << "Lbl: " << Label->getName();
328 }
329 #endif
330 
331 //===----------------------------------------------------------------------===//
332 // DIEDelta Implementation
333 //===----------------------------------------------------------------------===//
334 
335 /// EmitValue - Emit delta value.
336 ///
337 void DIEDelta::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
338   AP->EmitLabelDifference(LabelHi, LabelLo, SizeOf(AP, Form));
339 }
340 
341 /// SizeOf - Determine size of delta value in bytes.
342 ///
343 unsigned DIEDelta::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
344   if (Form == dwarf::DW_FORM_data4) return 4;
345   if (Form == dwarf::DW_FORM_sec_offset) return 4;
346   if (Form == dwarf::DW_FORM_strp) return 4;
347   return AP->getDataLayout().getPointerSize();
348 }
349 
350 #ifndef NDEBUG
351 void DIEDelta::print(raw_ostream &O) const {
352   O << "Del: " << LabelHi->getName() << "-" << LabelLo->getName();
353 }
354 #endif
355 
356 //===----------------------------------------------------------------------===//
357 // DIEString Implementation
358 //===----------------------------------------------------------------------===//
359 
360 /// EmitValue - Emit string value.
361 ///
362 void DIEString::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
363   Access->EmitValue(AP, Form);
364 }
365 
366 /// SizeOf - Determine size of delta value in bytes.
367 ///
368 unsigned DIEString::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
369   return Access->SizeOf(AP, Form);
370 }
371 
372 #ifndef NDEBUG
373 void DIEString::print(raw_ostream &O) const {
374   O << "String: " << Str << "\tSymbol: ";
375   Access->print(O);
376 }
377 #endif
378 
379 //===----------------------------------------------------------------------===//
380 // DIEEntry Implementation
381 //===----------------------------------------------------------------------===//
382 
383 /// EmitValue - Emit debug information entry offset.
384 ///
385 void DIEEntry::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
386   AP->EmitInt32(Entry->getOffset());
387 }
388 
389 unsigned DIEEntry::getRefAddrSize(AsmPrinter *AP) {
390   // DWARF4: References that use the attribute form DW_FORM_ref_addr are
391   // specified to be four bytes in the DWARF 32-bit format and eight bytes
392   // in the DWARF 64-bit format, while DWARF Version 2 specifies that such
393   // references have the same size as an address on the target system.
394   const DwarfDebug *DD = AP->getDwarfDebug();
395   assert(DD && "Expected Dwarf Debug info to be available");
396   if (DD->getDwarfVersion() == 2)
397     return AP->getDataLayout().getPointerSize();
398   return sizeof(int32_t);
399 }
400 
401 #ifndef NDEBUG
402 void DIEEntry::print(raw_ostream &O) const {
403   O << format("Die: 0x%lx", (long)(intptr_t)Entry);
404 }
405 #endif
406 
407 //===----------------------------------------------------------------------===//
408 // DIETypeSignature Implementation
409 //===----------------------------------------------------------------------===//
410 void DIETypeSignature::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
411   assert(Form == dwarf::DW_FORM_ref_sig8);
412   Asm->OutStreamer.EmitIntValue(Unit.getTypeSignature(), 8);
413 }
414 
415 #ifndef NDEBUG
416 void DIETypeSignature::print(raw_ostream &O) const {
417   O << format("Type Unit: 0x%lx", Unit.getTypeSignature());
418 }
419 
420 void DIETypeSignature::dump() const { print(dbgs()); }
421 #endif
422 
423 //===----------------------------------------------------------------------===//
424 // DIEBlock Implementation
425 //===----------------------------------------------------------------------===//
426 
427 /// ComputeSize - calculate the size of the block.
428 ///
429 unsigned DIEBlock::ComputeSize(AsmPrinter *AP) {
430   if (!Size) {
431     const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
432     for (unsigned i = 0, N = Values.size(); i < N; ++i)
433       Size += Values[i]->SizeOf(AP, AbbrevData[i].getForm());
434   }
435 
436   return Size;
437 }
438 
439 /// EmitValue - Emit block data.
440 ///
441 void DIEBlock::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
442   switch (Form) {
443   default: llvm_unreachable("Improper form for block");
444   case dwarf::DW_FORM_block1: Asm->EmitInt8(Size);    break;
445   case dwarf::DW_FORM_block2: Asm->EmitInt16(Size);   break;
446   case dwarf::DW_FORM_block4: Asm->EmitInt32(Size);   break;
447   case dwarf::DW_FORM_block:  Asm->EmitULEB128(Size); break;
448   }
449 
450   const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
451   for (unsigned i = 0, N = Values.size(); i < N; ++i)
452     Values[i]->EmitValue(Asm, AbbrevData[i].getForm());
453 }
454 
455 /// SizeOf - Determine size of block data in bytes.
456 ///
457 unsigned DIEBlock::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
458   switch (Form) {
459   case dwarf::DW_FORM_block1: return Size + sizeof(int8_t);
460   case dwarf::DW_FORM_block2: return Size + sizeof(int16_t);
461   case dwarf::DW_FORM_block4: return Size + sizeof(int32_t);
462   case dwarf::DW_FORM_block:  return Size + MCAsmInfo::getULEB128Size(Size);
463   default: llvm_unreachable("Improper form for block");
464   }
465 }
466 
467 #ifndef NDEBUG
468 void DIEBlock::print(raw_ostream &O) const {
469   O << "Blk: ";
470   DIE::print(O, 5);
471 }
472 #endif
473