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 "llvm/ADT/Twine.h"
17 #include "llvm/CodeGen/AsmPrinter.h"
18 #include "llvm/IR/DataLayout.h"
19 #include "llvm/MC/MCAsmInfo.h"
20 #include "llvm/MC/MCStreamer.h"
21 #include "llvm/MC/MCSymbol.h"
22 #include "llvm/Support/Allocator.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 compile unit DIE to which this DIE
116 /// belongs.
117 const DIE *DIE::getCompileUnit() const {
118   const DIE *Cu = getCompileUnitOrNull();
119   assert(Cu && "We should not have orphaned DIEs.");
120   return Cu;
121 }
122 
123 /// Climb up the parent chain to get the compile unit DIE this DIE belongs
124 /// to. Return NULL if DIE is not added to an owner yet.
125 const DIE *DIE::getCompileUnitOrNull() const {
126   const DIE *p = this;
127   while (p) {
128     if (p->getTag() == dwarf::DW_TAG_compile_unit)
129       return p;
130     p = p->getParent();
131   }
132   return NULL;
133 }
134 
135 DIEValue *DIE::findAttribute(uint16_t Attribute) {
136   const SmallVectorImpl<DIEValue *> &Values = getValues();
137   const DIEAbbrev &Abbrevs = getAbbrev();
138 
139   // Iterate through all the attributes until we find the one we're
140   // looking for, if we can't find it return NULL.
141   for (size_t i = 0; i < Values.size(); ++i)
142     if (Abbrevs.getData()[i].getAttribute() == Attribute)
143       return Values[i];
144   return NULL;
145 }
146 
147 #ifndef NDEBUG
148 void DIE::print(raw_ostream &O, unsigned IndentCount) const {
149   const std::string Indent(IndentCount, ' ');
150   bool isBlock = Abbrev.getTag() == 0;
151 
152   if (!isBlock) {
153     O << Indent
154       << "Die: "
155       << format("0x%lx", (long)(intptr_t)this)
156       << ", Offset: " << Offset
157       << ", Size: " << Size << "\n";
158 
159     O << Indent
160       << dwarf::TagString(Abbrev.getTag())
161       << " "
162       << dwarf::ChildrenString(Abbrev.getChildrenFlag()) << "\n";
163   } else {
164     O << "Size: " << Size << "\n";
165   }
166 
167   const SmallVectorImpl<DIEAbbrevData> &Data = Abbrev.getData();
168 
169   IndentCount += 2;
170   for (unsigned i = 0, N = Data.size(); i < N; ++i) {
171     O << Indent;
172 
173     if (!isBlock)
174       O << dwarf::AttributeString(Data[i].getAttribute());
175     else
176       O << "Blk[" << i << "]";
177 
178     O <<  "  "
179       << dwarf::FormEncodingString(Data[i].getForm())
180       << " ";
181     Values[i]->print(O);
182     O << "\n";
183   }
184   IndentCount -= 2;
185 
186   for (unsigned j = 0, M = Children.size(); j < M; ++j) {
187     Children[j]->print(O, IndentCount+4);
188   }
189 
190   if (!isBlock) O << "\n";
191 }
192 
193 void DIE::dump() {
194   print(dbgs());
195 }
196 #endif
197 
198 void DIEValue::anchor() { }
199 
200 #ifndef NDEBUG
201 void DIEValue::dump() const {
202   print(dbgs());
203 }
204 #endif
205 
206 //===----------------------------------------------------------------------===//
207 // DIEInteger Implementation
208 //===----------------------------------------------------------------------===//
209 
210 /// EmitValue - Emit integer of appropriate size.
211 ///
212 void DIEInteger::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
213   unsigned Size = ~0U;
214   switch (Form) {
215   case dwarf::DW_FORM_flag_present:
216     // Emit something to keep the lines and comments in sync.
217     // FIXME: Is there a better way to do this?
218     if (Asm->OutStreamer.hasRawTextSupport())
219       Asm->OutStreamer.EmitRawText("");
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_data8: Size = 8; break;
231   case dwarf::DW_FORM_GNU_str_index: Asm->EmitULEB128(Integer); return;
232   case dwarf::DW_FORM_GNU_addr_index: Asm->EmitULEB128(Integer); return;
233   case dwarf::DW_FORM_udata: Asm->EmitULEB128(Integer); return;
234   case dwarf::DW_FORM_sdata: Asm->EmitSLEB128(Integer); return;
235   case dwarf::DW_FORM_addr:
236     Size = Asm->getDataLayout().getPointerSize(); break;
237   default: llvm_unreachable("DIE Value form not supported yet");
238   }
239   Asm->OutStreamer.EmitIntValue(Integer, Size);
240 }
241 
242 /// SizeOf - Determine size of integer value in bytes.
243 ///
244 unsigned DIEInteger::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
245   switch (Form) {
246   case dwarf::DW_FORM_flag_present: return 0;
247   case dwarf::DW_FORM_flag:  // Fall thru
248   case dwarf::DW_FORM_ref1:  // Fall thru
249   case dwarf::DW_FORM_data1: return sizeof(int8_t);
250   case dwarf::DW_FORM_ref2:  // Fall thru
251   case dwarf::DW_FORM_data2: return sizeof(int16_t);
252   case dwarf::DW_FORM_sec_offset: // Fall thru
253   case dwarf::DW_FORM_ref4:  // Fall thru
254   case dwarf::DW_FORM_data4: return sizeof(int32_t);
255   case dwarf::DW_FORM_ref8:  // Fall thru
256   case dwarf::DW_FORM_data8: return sizeof(int64_t);
257   case dwarf::DW_FORM_GNU_str_index: return MCAsmInfo::getULEB128Size(Integer);
258   case dwarf::DW_FORM_GNU_addr_index: return MCAsmInfo::getULEB128Size(Integer);
259   case dwarf::DW_FORM_udata: return MCAsmInfo::getULEB128Size(Integer);
260   case dwarf::DW_FORM_sdata: return MCAsmInfo::getSLEB128Size(Integer);
261   case dwarf::DW_FORM_addr:  return AP->getDataLayout().getPointerSize();
262   default: llvm_unreachable("DIE Value form not supported yet");
263   }
264 }
265 
266 #ifndef NDEBUG
267 void DIEInteger::print(raw_ostream &O) const {
268   O << "Int: " << (int64_t)Integer << "  0x";
269   O.write_hex(Integer);
270 }
271 #endif
272 
273 //===----------------------------------------------------------------------===//
274 // DIEExpr Implementation
275 //===----------------------------------------------------------------------===//
276 
277 /// EmitValue - Emit expression value.
278 ///
279 void DIEExpr::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
280   AP->OutStreamer.EmitValue(Expr, SizeOf(AP, Form));
281 }
282 
283 /// SizeOf - Determine size of expression value in bytes.
284 ///
285 unsigned DIEExpr::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
286   if (Form == dwarf::DW_FORM_data4) return 4;
287   if (Form == dwarf::DW_FORM_sec_offset) return 4;
288   if (Form == dwarf::DW_FORM_strp) return 4;
289   return AP->getDataLayout().getPointerSize();
290 }
291 
292 #ifndef NDEBUG
293 void DIEExpr::print(raw_ostream &O) const {
294   O << "Expr: ";
295   Expr->print(O);
296 }
297 #endif
298 
299 //===----------------------------------------------------------------------===//
300 // DIELabel Implementation
301 //===----------------------------------------------------------------------===//
302 
303 /// EmitValue - Emit label value.
304 ///
305 void DIELabel::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
306   AP->EmitLabelReference(Label, SizeOf(AP, Form),
307                          Form == dwarf::DW_FORM_strp ||
308                              Form == dwarf::DW_FORM_sec_offset ||
309                              Form == dwarf::DW_FORM_ref_addr);
310 }
311 
312 /// SizeOf - Determine size of label value in bytes.
313 ///
314 unsigned DIELabel::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
315   if (Form == dwarf::DW_FORM_data4) return 4;
316   if (Form == dwarf::DW_FORM_sec_offset) return 4;
317   if (Form == dwarf::DW_FORM_strp) return 4;
318   return AP->getDataLayout().getPointerSize();
319 }
320 
321 #ifndef NDEBUG
322 void DIELabel::print(raw_ostream &O) const {
323   O << "Lbl: " << Label->getName();
324 }
325 #endif
326 
327 //===----------------------------------------------------------------------===//
328 // DIEDelta Implementation
329 //===----------------------------------------------------------------------===//
330 
331 /// EmitValue - Emit delta value.
332 ///
333 void DIEDelta::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
334   AP->EmitLabelDifference(LabelHi, LabelLo, SizeOf(AP, Form));
335 }
336 
337 /// SizeOf - Determine size of delta value in bytes.
338 ///
339 unsigned DIEDelta::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
340   if (Form == dwarf::DW_FORM_data4) return 4;
341   if (Form == dwarf::DW_FORM_strp) return 4;
342   return AP->getDataLayout().getPointerSize();
343 }
344 
345 #ifndef NDEBUG
346 void DIEDelta::print(raw_ostream &O) const {
347   O << "Del: " << LabelHi->getName() << "-" << LabelLo->getName();
348 }
349 #endif
350 
351 //===----------------------------------------------------------------------===//
352 // DIEString Implementation
353 //===----------------------------------------------------------------------===//
354 
355 /// EmitValue - Emit string value.
356 ///
357 void DIEString::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
358   Access->EmitValue(AP, Form);
359 }
360 
361 /// SizeOf - Determine size of delta value in bytes.
362 ///
363 unsigned DIEString::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
364   return Access->SizeOf(AP, Form);
365 }
366 
367 #ifndef NDEBUG
368 void DIEString::print(raw_ostream &O) const {
369   O << "String: " << Str << "\tSymbol: ";
370   Access->print(O);
371 }
372 #endif
373 
374 //===----------------------------------------------------------------------===//
375 // DIEEntry Implementation
376 //===----------------------------------------------------------------------===//
377 
378 /// EmitValue - Emit debug information entry offset.
379 ///
380 void DIEEntry::EmitValue(AsmPrinter *AP, dwarf::Form Form) const {
381   AP->EmitInt32(Entry->getOffset());
382 }
383 
384 unsigned DIEEntry::getRefAddrSize(AsmPrinter *AP) {
385   // DWARF4: References that use the attribute form DW_FORM_ref_addr are
386   // specified to be four bytes in the DWARF 32-bit format and eight bytes
387   // in the DWARF 64-bit format, while DWARF Version 2 specifies that such
388   // references have the same size as an address on the target system.
389   if (AP->getDwarfDebug()->getDwarfVersion() == 2)
390     return AP->getDataLayout().getPointerSize();
391   return sizeof(int32_t);
392 }
393 
394 #ifndef NDEBUG
395 void DIEEntry::print(raw_ostream &O) const {
396   O << format("Die: 0x%lx", (long)(intptr_t)Entry);
397 }
398 #endif
399 
400 //===----------------------------------------------------------------------===//
401 // DIEBlock Implementation
402 //===----------------------------------------------------------------------===//
403 
404 /// ComputeSize - calculate the size of the block.
405 ///
406 unsigned DIEBlock::ComputeSize(AsmPrinter *AP) {
407   if (!Size) {
408     const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
409     for (unsigned i = 0, N = Values.size(); i < N; ++i)
410       Size += Values[i]->SizeOf(AP, AbbrevData[i].getForm());
411   }
412 
413   return Size;
414 }
415 
416 /// EmitValue - Emit block data.
417 ///
418 void DIEBlock::EmitValue(AsmPrinter *Asm, dwarf::Form Form) const {
419   switch (Form) {
420   default: llvm_unreachable("Improper form for block");
421   case dwarf::DW_FORM_block1: Asm->EmitInt8(Size);    break;
422   case dwarf::DW_FORM_block2: Asm->EmitInt16(Size);   break;
423   case dwarf::DW_FORM_block4: Asm->EmitInt32(Size);   break;
424   case dwarf::DW_FORM_block:  Asm->EmitULEB128(Size); break;
425   }
426 
427   const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
428   for (unsigned i = 0, N = Values.size(); i < N; ++i)
429     Values[i]->EmitValue(Asm, AbbrevData[i].getForm());
430 }
431 
432 /// SizeOf - Determine size of block data in bytes.
433 ///
434 unsigned DIEBlock::SizeOf(AsmPrinter *AP, dwarf::Form Form) const {
435   switch (Form) {
436   case dwarf::DW_FORM_block1: return Size + sizeof(int8_t);
437   case dwarf::DW_FORM_block2: return Size + sizeof(int16_t);
438   case dwarf::DW_FORM_block4: return Size + sizeof(int32_t);
439   case dwarf::DW_FORM_block:  return Size + MCAsmInfo::getULEB128Size(Size);
440   default: llvm_unreachable("Improper form for block");
441   }
442 }
443 
444 #ifndef NDEBUG
445 void DIEBlock::print(raw_ostream &O) const {
446   O << "Blk: ";
447   DIE::print(O, 5);
448 }
449 #endif
450