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