MachineModuleInfo.cpp revision 0ff39b3feb10477c224138156941234f5fa46f58 
1//===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
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#include "llvm/CodeGen/MachineModuleInfo.h"
11
12#include "llvm/Constants.h"
13#include "llvm/Analysis/ValueTracking.h"
14#include "llvm/CodeGen/MachineFunctionPass.h"
15#include "llvm/CodeGen/MachineFunction.h"
16#include "llvm/CodeGen/MachineLocation.h"
17#include "llvm/CodeGen/MachineDebugInfoDesc.h"
18#include "llvm/Target/TargetInstrInfo.h"
19#include "llvm/Target/TargetMachine.h"
20#include "llvm/Target/TargetOptions.h"
21#include "llvm/DerivedTypes.h"
22#include "llvm/GlobalVariable.h"
23#include "llvm/Intrinsics.h"
24#include "llvm/Instructions.h"
25#include "llvm/Module.h"
26#include "llvm/Support/Dwarf.h"
27#include "llvm/Support/Streams.h"
28using namespace llvm;
29using namespace llvm::dwarf;
30
31// Handle the Pass registration stuff necessary to use TargetData's.
32static RegisterPass<MachineModuleInfo>
33X("machinemoduleinfo", "Module Information");
34char MachineModuleInfo::ID = 0;
35
36//===----------------------------------------------------------------------===//
37
38/// getGlobalVariablesUsing - Return all of the GlobalVariables which have the
39/// specified value in their initializer somewhere.
40static void
41getGlobalVariablesUsing(Value *V, std::vector<GlobalVariable*> &Result) {
42  // Scan though value users.
43  for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) {
44    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I)) {
45      // If the user is a GlobalVariable then add to result.
46      Result.push_back(GV);
47    } else if (Constant *C = dyn_cast<Constant>(*I)) {
48      // If the user is a constant variable then scan its users
49      getGlobalVariablesUsing(C, Result);
50    }
51  }
52}
53
54/// getGlobalVariablesUsing - Return all of the GlobalVariables that use the
55/// named GlobalVariable.
56static void
57getGlobalVariablesUsing(Module &M, const std::string &RootName,
58                        std::vector<GlobalVariable*> &Result) {
59  std::vector<const Type*> FieldTypes;
60  FieldTypes.push_back(Type::Int32Ty);
61  FieldTypes.push_back(Type::Int32Ty);
62
63  // Get the GlobalVariable root.
64  GlobalVariable *UseRoot = M.getGlobalVariable(RootName,
65                                                StructType::get(FieldTypes));
66
67  // If present and linkonce then scan for users.
68  if (UseRoot && UseRoot->hasLinkOnceLinkage())
69    getGlobalVariablesUsing(UseRoot, Result);
70}
71
72/// isStringValue - Return true if the given value can be coerced to a string.
73///
74static bool isStringValue(Value *V) {
75  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
76    if (GV->hasInitializer() && isa<ConstantArray>(GV->getInitializer())) {
77      ConstantArray *Init = cast<ConstantArray>(GV->getInitializer());
78      return Init->isString();
79    }
80  } else if (Constant *C = dyn_cast<Constant>(V)) {
81    if (GlobalValue *GV = dyn_cast<GlobalValue>(C))
82      return isStringValue(GV);
83    else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
84      if (CE->getOpcode() == Instruction::GetElementPtr) {
85        if (CE->getNumOperands() == 3 &&
86            cast<Constant>(CE->getOperand(1))->isNullValue() &&
87            isa<ConstantInt>(CE->getOperand(2))) {
88          return isStringValue(CE->getOperand(0));
89        }
90      }
91    }
92  }
93  return false;
94}
95
96/// getGlobalVariable - Return either a direct or cast Global value.
97///
98static GlobalVariable *getGlobalVariable(Value *V) {
99  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
100    return GV;
101  } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
102    if (CE->getOpcode() == Instruction::BitCast) {
103      return dyn_cast<GlobalVariable>(CE->getOperand(0));
104    } else if (CE->getOpcode() == Instruction::GetElementPtr) {
105      for (unsigned int i=1; i<CE->getNumOperands(); i++) {
106        if (!CE->getOperand(i)->isNullValue())
107          return NULL;
108      }
109      return dyn_cast<GlobalVariable>(CE->getOperand(0));
110    }
111  }
112  return NULL;
113}
114
115/// isGlobalVariable - Return true if the given value can be coerced to a
116/// GlobalVariable.
117static bool isGlobalVariable(Value *V) {
118  if (isa<GlobalVariable>(V) || isa<ConstantPointerNull>(V)) {
119    return true;
120  } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
121    if (CE->getOpcode() == Instruction::BitCast) {
122      return isa<GlobalVariable>(CE->getOperand(0));
123    } else if (CE->getOpcode() == Instruction::GetElementPtr) {
124      for (unsigned int i=1; i<CE->getNumOperands(); i++) {
125        if (!CE->getOperand(i)->isNullValue())
126          return false;
127      }
128      return isa<GlobalVariable>(CE->getOperand(0));
129    }
130  }
131  return false;
132}
133
134//===----------------------------------------------------------------------===//
135
136/// ApplyToFields - Target the visitor to each field of the debug information
137/// descriptor.
138void DIVisitor::ApplyToFields(DebugInfoDesc *DD) {
139  DD->ApplyToFields(this);
140}
141
142namespace {
143
144//===----------------------------------------------------------------------===//
145/// DICountVisitor - This DIVisitor counts all the fields in the supplied debug
146/// the supplied DebugInfoDesc.
147class DICountVisitor : public DIVisitor {
148private:
149  unsigned Count;                       // Running count of fields.
150
151public:
152  DICountVisitor() : DIVisitor(), Count(0) {}
153
154  // Accessors.
155  unsigned getCount() const { return Count; }
156
157  /// Apply - Count each of the fields.
158  ///
159  virtual void Apply(int &Field)             { ++Count; }
160  virtual void Apply(unsigned &Field)        { ++Count; }
161  virtual void Apply(int64_t &Field)         { ++Count; }
162  virtual void Apply(uint64_t &Field)        { ++Count; }
163  virtual void Apply(bool &Field)            { ++Count; }
164  virtual void Apply(std::string &Field)     { ++Count; }
165  virtual void Apply(DebugInfoDesc *&Field)  { ++Count; }
166  virtual void Apply(GlobalVariable *&Field) { ++Count; }
167  virtual void Apply(std::vector<DebugInfoDesc *> &Field) {
168    ++Count;
169  }
170};
171
172//===----------------------------------------------------------------------===//
173/// DIDeserializeVisitor - This DIVisitor deserializes all the fields in the
174/// supplied DebugInfoDesc.
175class DIDeserializeVisitor : public DIVisitor {
176private:
177  DIDeserializer &DR;                   // Active deserializer.
178  unsigned I;                           // Current operand index.
179  ConstantStruct *CI;                   // GlobalVariable constant initializer.
180
181public:
182  DIDeserializeVisitor(DIDeserializer &D, GlobalVariable *GV)
183    : DIVisitor(), DR(D), I(0), CI(cast<ConstantStruct>(GV->getInitializer()))
184  {}
185
186  /// Apply - Set the value of each of the fields.
187  ///
188  virtual void Apply(int &Field) {
189    Constant *C = CI->getOperand(I++);
190    Field = cast<ConstantInt>(C)->getSExtValue();
191  }
192  virtual void Apply(unsigned &Field) {
193    Constant *C = CI->getOperand(I++);
194    Field = cast<ConstantInt>(C)->getZExtValue();
195  }
196  virtual void Apply(int64_t &Field) {
197    Constant *C = CI->getOperand(I++);
198    Field = cast<ConstantInt>(C)->getSExtValue();
199  }
200  virtual void Apply(uint64_t &Field) {
201    Constant *C = CI->getOperand(I++);
202    Field = cast<ConstantInt>(C)->getZExtValue();
203  }
204  virtual void Apply(bool &Field) {
205    Constant *C = CI->getOperand(I++);
206    Field = cast<ConstantInt>(C)->getZExtValue();
207  }
208  virtual void Apply(std::string &Field) {
209    Constant *C = CI->getOperand(I++);
210    // Fills in the string if it succeeds
211    if (!GetConstantStringInfo(C, Field))
212      Field.clear();
213  }
214  virtual void Apply(DebugInfoDesc *&Field) {
215    Constant *C = CI->getOperand(I++);
216    Field = DR.Deserialize(C);
217  }
218  virtual void Apply(GlobalVariable *&Field) {
219    Constant *C = CI->getOperand(I++);
220    Field = getGlobalVariable(C);
221  }
222  virtual void Apply(std::vector<DebugInfoDesc *> &Field) {
223    Field.resize(0);
224    Constant *C = CI->getOperand(I++);
225    GlobalVariable *GV = getGlobalVariable(C);
226    if (GV->hasInitializer()) {
227      if (ConstantArray *CA = dyn_cast<ConstantArray>(GV->getInitializer())) {
228        for (unsigned i = 0, N = CA->getNumOperands(); i < N; ++i) {
229          GlobalVariable *GVE = getGlobalVariable(CA->getOperand(i));
230          DebugInfoDesc *DE = DR.Deserialize(GVE);
231          Field.push_back(DE);
232        }
233      } else if (GV->getInitializer()->isNullValue()) {
234        if (const ArrayType *T =
235            dyn_cast<ArrayType>(GV->getType()->getElementType())) {
236          Field.resize(T->getNumElements());
237        }
238      }
239    }
240  }
241};
242
243//===----------------------------------------------------------------------===//
244/// DISerializeVisitor - This DIVisitor serializes all the fields in
245/// the supplied DebugInfoDesc.
246class DISerializeVisitor : public DIVisitor {
247private:
248  DISerializer &SR;                     // Active serializer.
249  std::vector<Constant*> &Elements;     // Element accumulator.
250
251public:
252  DISerializeVisitor(DISerializer &S, std::vector<Constant*> &E)
253  : DIVisitor()
254  , SR(S)
255  , Elements(E)
256  {}
257
258  /// Apply - Set the value of each of the fields.
259  ///
260  virtual void Apply(int &Field) {
261    Elements.push_back(ConstantInt::get(Type::Int32Ty, int32_t(Field)));
262  }
263  virtual void Apply(unsigned &Field) {
264    Elements.push_back(ConstantInt::get(Type::Int32Ty, uint32_t(Field)));
265  }
266  virtual void Apply(int64_t &Field) {
267    Elements.push_back(ConstantInt::get(Type::Int64Ty, int64_t(Field)));
268  }
269  virtual void Apply(uint64_t &Field) {
270    Elements.push_back(ConstantInt::get(Type::Int64Ty, uint64_t(Field)));
271  }
272  virtual void Apply(bool &Field) {
273    Elements.push_back(ConstantInt::get(Type::Int1Ty, Field));
274  }
275  virtual void Apply(std::string &Field) {
276    Elements.push_back(SR.getString(Field));
277  }
278  virtual void Apply(DebugInfoDesc *&Field) {
279    GlobalVariable *GV = NULL;
280
281    // If non-NULL then convert to global.
282    if (Field) GV = SR.Serialize(Field);
283
284    // FIXME - At some point should use specific type.
285    const PointerType *EmptyTy = SR.getEmptyStructPtrType();
286
287    if (GV) {
288      // Set to pointer to global.
289      Elements.push_back(ConstantExpr::getBitCast(GV, EmptyTy));
290    } else {
291      // Use NULL.
292      Elements.push_back(ConstantPointerNull::get(EmptyTy));
293    }
294  }
295  virtual void Apply(GlobalVariable *&Field) {
296    const PointerType *EmptyTy = SR.getEmptyStructPtrType();
297    if (Field) {
298      Elements.push_back(ConstantExpr::getBitCast(Field, EmptyTy));
299    } else {
300      Elements.push_back(ConstantPointerNull::get(EmptyTy));
301    }
302  }
303  virtual void Apply(std::vector<DebugInfoDesc *> &Field) {
304    const PointerType *EmptyTy = SR.getEmptyStructPtrType();
305    unsigned N = Field.size();
306    ArrayType *AT = ArrayType::get(EmptyTy, N);
307    std::vector<Constant *> ArrayElements;
308
309    for (unsigned i = 0; i < N; ++i) {
310      if (DebugInfoDesc *Element = Field[i]) {
311        GlobalVariable *GVE = SR.Serialize(Element);
312        Constant *CE = ConstantExpr::getBitCast(GVE, EmptyTy);
313        ArrayElements.push_back(cast<Constant>(CE));
314      } else {
315        ArrayElements.push_back(ConstantPointerNull::get(EmptyTy));
316      }
317    }
318
319    Constant *CA = ConstantArray::get(AT, ArrayElements);
320    GlobalVariable *CAGV = new GlobalVariable(AT, true,
321                                              GlobalValue::InternalLinkage,
322                                              CA, "llvm.dbg.array",
323                                              SR.getModule());
324    CAGV->setSection("llvm.metadata");
325    Constant *CAE = ConstantExpr::getBitCast(CAGV, EmptyTy);
326    Elements.push_back(CAE);
327  }
328};
329
330//===----------------------------------------------------------------------===//
331/// DIGetTypesVisitor - This DIVisitor gathers all the field types in
332/// the supplied DebugInfoDesc.
333class DIGetTypesVisitor : public DIVisitor {
334private:
335  DISerializer &SR;                     // Active serializer.
336  std::vector<const Type*> &Fields;     // Type accumulator.
337
338public:
339  DIGetTypesVisitor(DISerializer &S, std::vector<const Type*> &F)
340  : DIVisitor()
341  , SR(S)
342  , Fields(F)
343  {}
344
345  /// Apply - Set the value of each of the fields.
346  ///
347  virtual void Apply(int &Field) {
348    Fields.push_back(Type::Int32Ty);
349  }
350  virtual void Apply(unsigned &Field) {
351    Fields.push_back(Type::Int32Ty);
352  }
353  virtual void Apply(int64_t &Field) {
354    Fields.push_back(Type::Int64Ty);
355  }
356  virtual void Apply(uint64_t &Field) {
357    Fields.push_back(Type::Int64Ty);
358  }
359  virtual void Apply(bool &Field) {
360    Fields.push_back(Type::Int1Ty);
361  }
362  virtual void Apply(std::string &Field) {
363    Fields.push_back(SR.getStrPtrType());
364  }
365  virtual void Apply(DebugInfoDesc *&Field) {
366    // FIXME - At some point should use specific type.
367    const PointerType *EmptyTy = SR.getEmptyStructPtrType();
368    Fields.push_back(EmptyTy);
369  }
370  virtual void Apply(GlobalVariable *&Field) {
371    const PointerType *EmptyTy = SR.getEmptyStructPtrType();
372    Fields.push_back(EmptyTy);
373  }
374  virtual void Apply(std::vector<DebugInfoDesc *> &Field) {
375    const PointerType *EmptyTy = SR.getEmptyStructPtrType();
376    Fields.push_back(EmptyTy);
377  }
378};
379
380//===----------------------------------------------------------------------===//
381/// DIVerifyVisitor - This DIVisitor verifies all the field types against
382/// a constant initializer.
383class DIVerifyVisitor : public DIVisitor {
384private:
385  DIVerifier &VR;                       // Active verifier.
386  bool IsValid;                         // Validity status.
387  unsigned I;                           // Current operand index.
388  ConstantStruct *CI;                   // GlobalVariable constant initializer.
389
390public:
391  DIVerifyVisitor(DIVerifier &V, GlobalVariable *GV)
392  : DIVisitor()
393  , VR(V)
394  , IsValid(true)
395  , I(0)
396  , CI(cast<ConstantStruct>(GV->getInitializer()))
397  {
398  }
399
400  // Accessors.
401  bool isValid() const { return IsValid; }
402
403  /// Apply - Set the value of each of the fields.
404  ///
405  virtual void Apply(int &Field) {
406    Constant *C = CI->getOperand(I++);
407    IsValid = IsValid && isa<ConstantInt>(C);
408  }
409  virtual void Apply(unsigned &Field) {
410    Constant *C = CI->getOperand(I++);
411    IsValid = IsValid && isa<ConstantInt>(C);
412  }
413  virtual void Apply(int64_t &Field) {
414    Constant *C = CI->getOperand(I++);
415    IsValid = IsValid && isa<ConstantInt>(C);
416  }
417  virtual void Apply(uint64_t &Field) {
418    Constant *C = CI->getOperand(I++);
419    IsValid = IsValid && isa<ConstantInt>(C);
420  }
421  virtual void Apply(bool &Field) {
422    Constant *C = CI->getOperand(I++);
423    IsValid = IsValid && isa<ConstantInt>(C) && C->getType() == Type::Int1Ty;
424  }
425  virtual void Apply(std::string &Field) {
426    Constant *C = CI->getOperand(I++);
427    IsValid = IsValid &&
428              (!C || isStringValue(C) || C->isNullValue());
429  }
430  virtual void Apply(DebugInfoDesc *&Field) {
431    // FIXME - Prepare the correct descriptor.
432    Constant *C = CI->getOperand(I++);
433    IsValid = IsValid && isGlobalVariable(C);
434  }
435  virtual void Apply(GlobalVariable *&Field) {
436    Constant *C = CI->getOperand(I++);
437    IsValid = IsValid && isGlobalVariable(C);
438  }
439  virtual void Apply(std::vector<DebugInfoDesc *> &Field) {
440    Constant *C = CI->getOperand(I++);
441    IsValid = IsValid && isGlobalVariable(C);
442    if (!IsValid) return;
443
444    GlobalVariable *GV = getGlobalVariable(C);
445    IsValid = IsValid && GV && GV->hasInitializer();
446    if (!IsValid) return;
447
448    ConstantArray *CA = dyn_cast<ConstantArray>(GV->getInitializer());
449    IsValid = IsValid && CA;
450    if (!IsValid) return;
451
452    for (unsigned i = 0, N = CA->getNumOperands(); IsValid && i < N; ++i) {
453      IsValid = IsValid && isGlobalVariable(CA->getOperand(i));
454      if (!IsValid) return;
455
456      GlobalVariable *GVE = getGlobalVariable(CA->getOperand(i));
457      VR.Verify(GVE);
458    }
459  }
460};
461
462}
463
464//===----------------------------------------------------------------------===//
465
466DebugInfoDesc *DIDeserializer::Deserialize(Value *V) {
467  return Deserialize(getGlobalVariable(V));
468}
469DebugInfoDesc *DIDeserializer::Deserialize(GlobalVariable *GV) {
470  // Handle NULL.
471  if (!GV) return NULL;
472
473  // Check to see if it has been already deserialized.
474  DebugInfoDesc *&Slot = GlobalDescs[GV];
475  if (Slot) return Slot;
476
477  // Get the Tag from the global.
478  unsigned Tag = DebugInfoDesc::TagFromGlobal(GV);
479
480  // Create an empty instance of the correct sort.
481  Slot = DebugInfoDesc::DescFactory(Tag);
482
483  // If not a user defined descriptor.
484  if (Slot) {
485    // Deserialize the fields.
486    DIDeserializeVisitor DRAM(*this, GV);
487    DRAM.ApplyToFields(Slot);
488  }
489
490  return Slot;
491}
492
493//===----------------------------------------------------------------------===//
494
495/// getStrPtrType - Return a "sbyte *" type.
496///
497const PointerType *DISerializer::getStrPtrType() {
498  // If not already defined.
499  if (!StrPtrTy) {
500    // Construct the pointer to signed bytes.
501    StrPtrTy = PointerType::getUnqual(Type::Int8Ty);
502  }
503
504  return StrPtrTy;
505}
506
507/// getEmptyStructPtrType - Return a "{ }*" type.
508///
509const PointerType *DISerializer::getEmptyStructPtrType() {
510  // If not already defined.
511  if (EmptyStructPtrTy) return EmptyStructPtrTy;
512
513  // Construct the pointer to empty structure type.
514  const StructType *EmptyStructTy =
515    StructType::get(std::vector<const Type*>());
516
517  // Construct the pointer to empty structure type.
518  EmptyStructPtrTy = PointerType::getUnqual(EmptyStructTy);
519  return EmptyStructPtrTy;
520}
521
522/// getTagType - Return the type describing the specified descriptor (via tag.)
523///
524const StructType *DISerializer::getTagType(DebugInfoDesc *DD) {
525  // Attempt to get the previously defined type.
526  StructType *&Ty = TagTypes[DD->getTag()];
527
528  // If not already defined.
529  if (!Ty) {
530    // Set up fields vector.
531    std::vector<const Type*> Fields;
532    // Get types of fields.
533    DIGetTypesVisitor GTAM(*this, Fields);
534    GTAM.ApplyToFields(DD);
535
536    // Construct structured type.
537    Ty = StructType::get(Fields);
538
539    // Register type name with module.
540    M->addTypeName(DD->getTypeString(), Ty);
541  }
542
543  return Ty;
544}
545
546/// getString - Construct the string as constant string global.
547///
548Constant *DISerializer::getString(const std::string &String) {
549  // Check string cache for previous edition.
550  Constant *&Slot = StringCache[String.c_str()];
551
552  // Return Constant if previously defined.
553  if (Slot) return Slot;
554
555  // If empty string then use a sbyte* null instead.
556  if (String.empty()) {
557    Slot = ConstantPointerNull::get(getStrPtrType());
558  } else {
559    // Construct string as an llvm constant.
560    Constant *ConstStr = ConstantArray::get(String);
561
562    // Otherwise create and return a new string global.
563    GlobalVariable *StrGV = new GlobalVariable(ConstStr->getType(), true,
564                                               GlobalVariable::InternalLinkage,
565                                               ConstStr, ".str", M);
566    StrGV->setSection("llvm.metadata");
567
568    // Convert to generic string pointer.
569    Slot = ConstantExpr::getBitCast(StrGV, getStrPtrType());
570  }
571
572  return Slot;
573
574}
575
576/// Serialize - Recursively cast the specified descriptor into a GlobalVariable
577/// so that it can be serialized to a .bc or .ll file.
578GlobalVariable *DISerializer::Serialize(DebugInfoDesc *DD) {
579  // Check if the DebugInfoDesc is already in the map.
580  GlobalVariable *&Slot = DescGlobals[DD];
581
582  // See if DebugInfoDesc exists, if so return prior GlobalVariable.
583  if (Slot) return Slot;
584
585  // Get the type associated with the Tag.
586  const StructType *Ty = getTagType(DD);
587
588  // Create the GlobalVariable early to prevent infinite recursion.
589  GlobalVariable *GV = new GlobalVariable(Ty, true, DD->getLinkage(),
590                                          NULL, DD->getDescString(), M);
591  GV->setSection("llvm.metadata");
592
593  // Insert new GlobalVariable in DescGlobals map.
594  Slot = GV;
595
596  // Set up elements vector
597  std::vector<Constant*> Elements;
598  // Add fields.
599  DISerializeVisitor SRAM(*this, Elements);
600  SRAM.ApplyToFields(DD);
601
602  // Set the globals initializer.
603  GV->setInitializer(ConstantStruct::get(Ty, Elements));
604
605  return GV;
606}
607
608/// addDescriptor - Directly connect DD with existing GV.
609void DISerializer::addDescriptor(DebugInfoDesc *DD,
610                                 GlobalVariable *GV) {
611  DescGlobals[DD] = GV;
612}
613
614//===----------------------------------------------------------------------===//
615
616/// Verify - Return true if the GlobalVariable appears to be a valid
617/// serialization of a DebugInfoDesc.
618bool DIVerifier::Verify(Value *V) {
619  return !V || Verify(getGlobalVariable(V));
620}
621bool DIVerifier::Verify(GlobalVariable *GV) {
622  // NULLs are valid.
623  if (!GV) return true;
624
625  // Check prior validity.
626  unsigned &ValiditySlot = Validity[GV];
627
628  // If visited before then use old state.
629  if (ValiditySlot) return ValiditySlot == Valid;
630
631  // Assume validity for the time being (recursion.)
632  ValiditySlot = Valid;
633
634  // Make sure the global is internal or link once (anchor.)
635  if (GV->getLinkage() != GlobalValue::InternalLinkage &&
636      GV->getLinkage() != GlobalValue::LinkOnceLinkage) {
637    ValiditySlot = Invalid;
638    return false;
639  }
640
641  // Get the Tag.
642  unsigned Tag = DebugInfoDesc::TagFromGlobal(GV);
643
644  // Check for user defined descriptors.
645  if (Tag == DW_TAG_invalid) {
646    ValiditySlot = Valid;
647    return true;
648  }
649
650  // Get the Version.
651  unsigned Version = DebugInfoDesc::VersionFromGlobal(GV);
652
653  // Check for version mismatch.
654  if (Version != LLVMDebugVersion) {
655    ValiditySlot = Invalid;
656    return false;
657  }
658
659  // Construct an empty DebugInfoDesc.
660  DebugInfoDesc *DD = DebugInfoDesc::DescFactory(Tag);
661
662  // Allow for user defined descriptors.
663  if (!DD) return true;
664
665  // Get the initializer constant.
666  ConstantStruct *CI = cast<ConstantStruct>(GV->getInitializer());
667
668  // Get the operand count.
669  unsigned N = CI->getNumOperands();
670
671  // Get the field count.
672  unsigned &CountSlot = Counts[Tag];
673  if (!CountSlot) {
674    // Check the operand count to the field count
675    DICountVisitor CTAM;
676    CTAM.ApplyToFields(DD);
677    CountSlot = CTAM.getCount();
678  }
679
680  // Field count must be at most equal operand count.
681  if (CountSlot >  N) {
682    delete DD;
683    ValiditySlot = Invalid;
684    return false;
685  }
686
687  // Check each field for valid type.
688  DIVerifyVisitor VRAM(*this, GV);
689  VRAM.ApplyToFields(DD);
690
691  // Release empty DebugInfoDesc.
692  delete DD;
693
694  // If fields are not valid.
695  if (!VRAM.isValid()) {
696    ValiditySlot = Invalid;
697    return false;
698  }
699
700  return true;
701}
702
703/// isVerified - Return true if the specified GV has already been
704/// verified as a debug information descriptor.
705bool DIVerifier::isVerified(GlobalVariable *GV) {
706  unsigned &ValiditySlot = Validity[GV];
707  if (ValiditySlot) return ValiditySlot == Valid;
708  return false;
709}
710
711//===----------------------------------------------------------------------===//
712
713DebugScope::~DebugScope() {
714  for (unsigned i = 0, e = Scopes.size(); i < e; ++i) delete Scopes[i];
715  for (unsigned i = 0, e = Variables.size(); i < e; ++i) delete Variables[i];
716}
717
718//===----------------------------------------------------------------------===//
719
720MachineModuleInfo::MachineModuleInfo()
721: ImmutablePass((intptr_t)&ID)
722, DR()
723, VR()
724, CompileUnits()
725, Directories()
726, SourceFiles()
727, Lines()
728, LabelIDList()
729, ScopeMap()
730, RootScope(NULL)
731, FrameMoves()
732, LandingPads()
733, Personalities()
734, CallsEHReturn(0)
735, CallsUnwindInit(0)
736{
737  // Always emit "no personality" info
738  Personalities.push_back(NULL);
739}
740MachineModuleInfo::~MachineModuleInfo() {
741
742}
743
744/// doInitialization - Initialize the state for a new module.
745///
746bool MachineModuleInfo::doInitialization() {
747  return false;
748}
749
750/// doFinalization - Tear down the state after completion of a module.
751///
752bool MachineModuleInfo::doFinalization() {
753  return false;
754}
755
756/// BeginFunction - Begin gathering function meta information.
757///
758void MachineModuleInfo::BeginFunction(MachineFunction *MF) {
759  // Coming soon.
760}
761
762/// EndFunction - Discard function meta information.
763///
764void MachineModuleInfo::EndFunction() {
765  // Clean up scope information.
766  if (RootScope) {
767    delete RootScope;
768    ScopeMap.clear();
769    RootScope = NULL;
770  }
771
772  // Clean up line info.
773  Lines.clear();
774
775  // Clean up frame info.
776  FrameMoves.clear();
777
778  // Clean up exception info.
779  LandingPads.clear();
780  TypeInfos.clear();
781  FilterIds.clear();
782  FilterEnds.clear();
783  CallsEHReturn = 0;
784  CallsUnwindInit = 0;
785}
786
787/// getDescFor - Convert a Value to a debug information descriptor.
788///
789// FIXME - use new Value type when available.
790DebugInfoDesc *MachineModuleInfo::getDescFor(Value *V) {
791  return DR.Deserialize(V);
792}
793
794/// AnalyzeModule - Scan the module for global debug information.
795///
796void MachineModuleInfo::AnalyzeModule(Module &M) {
797  SetupCompileUnits(M);
798
799  // Insert functions in the llvm.used array into UsedFunctions.
800  GlobalVariable *GV = M.getGlobalVariable("llvm.used");
801  if (!GV || !GV->hasInitializer()) return;
802
803  // Should be an array of 'i8*'.
804  ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
805  if (InitList == 0) return;
806
807  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
808    if (ConstantExpr *CE = dyn_cast<ConstantExpr>(InitList->getOperand(i)))
809      if (CE->getOpcode() == Instruction::BitCast)
810        if (Function *F = dyn_cast<Function>(CE->getOperand(0)))
811          UsedFunctions.insert(F);
812  }
813}
814
815/// SetupCompileUnits - Set up the unique vector of compile units.
816///
817void MachineModuleInfo::SetupCompileUnits(Module &M) {
818  std::vector<void*> CUList;
819  CompileUnitDesc CUD;
820  getAnchoredDescriptors(M, &CUD, CUList);
821
822  for (unsigned i = 0, e = CUList.size(); i < e; i++)
823    CompileUnits.insert((CompileUnitDesc*)CUList[i]);
824}
825
826/// getCompileUnits - Return a vector of debug compile units.
827///
828const UniqueVector<CompileUnitDesc *> MachineModuleInfo::getCompileUnits()const{
829  return CompileUnits;
830}
831
832/// getAnchoredDescriptors - Return a vector of anchored debug descriptors.
833///
834void
835MachineModuleInfo::getAnchoredDescriptors(Module &M, const AnchoredDesc *Desc,
836                                          std::vector<void*> &AnchoredDescs) {
837  std::vector<GlobalVariable*> Globals;
838  getGlobalVariablesUsing(M, Desc->getAnchorString(), Globals);
839
840  for (unsigned i = 0, e = Globals.size(); i < e; ++i) {
841    GlobalVariable *GV = Globals[i];
842
843    // FIXME - In the short term, changes are too drastic to continue.
844    if (DebugInfoDesc::TagFromGlobal(GV) == Desc->getTag() &&
845        DebugInfoDesc::VersionFromGlobal(GV) == LLVMDebugVersion)
846      AnchoredDescs.push_back(DR.Deserialize(GV));
847  }
848}
849
850/// getGlobalVariablesUsing - Return all of the GlobalVariables that use the
851/// named GlobalVariable.
852void
853MachineModuleInfo::getGlobalVariablesUsing(Module &M,
854                                           const std::string &RootName,
855                                        std::vector<GlobalVariable*> &Globals) {
856  return ::getGlobalVariablesUsing(M, RootName, Globals);
857}
858
859/// RecordSourceLine - Records location information and associates it with a
860/// debug label.  Returns a unique label ID used to generate a label and
861/// provide correspondence to the source line list.
862unsigned MachineModuleInfo::RecordSourceLine(unsigned Line, unsigned Column,
863                                             unsigned Source) {
864  unsigned ID = NextLabelID();
865  Lines.push_back(SourceLineInfo(Line, Column, Source, ID));
866  return ID;
867}
868
869/// RecordSource - Register a source file with debug info. Returns an source
870/// ID.
871unsigned MachineModuleInfo::RecordSource(const std::string &Directory,
872                                         const std::string &Source) {
873  unsigned DirectoryID = Directories.insert(Directory);
874  return SourceFiles.insert(SourceFileInfo(DirectoryID, Source));
875}
876unsigned MachineModuleInfo::RecordSource(const CompileUnitDesc *CompileUnit) {
877  return RecordSource(CompileUnit->getDirectory(),
878                      CompileUnit->getFileName());
879}
880
881/// RecordRegionStart - Indicate the start of a region.
882///
883unsigned MachineModuleInfo::RecordRegionStart(Value *V) {
884  // FIXME - need to be able to handle split scopes because of bb cloning.
885  DebugInfoDesc *ScopeDesc = DR.Deserialize(V);
886  DebugScope *Scope = getOrCreateScope(ScopeDesc);
887  unsigned ID = NextLabelID();
888  if (!Scope->getStartLabelID()) Scope->setStartLabelID(ID);
889  return ID;
890}
891
892/// RecordRegionEnd - Indicate the end of a region.
893///
894unsigned MachineModuleInfo::RecordRegionEnd(Value *V) {
895  // FIXME - need to be able to handle split scopes because of bb cloning.
896  DebugInfoDesc *ScopeDesc = DR.Deserialize(V);
897  DebugScope *Scope = getOrCreateScope(ScopeDesc);
898  unsigned ID = NextLabelID();
899  Scope->setEndLabelID(ID);
900  return ID;
901}
902
903/// RecordVariable - Indicate the declaration of  a local variable.
904///
905void MachineModuleInfo::RecordVariable(GlobalValue *GV, unsigned FrameIndex) {
906  VariableDesc *VD = cast<VariableDesc>(DR.Deserialize(GV));
907  DebugScope *Scope = getOrCreateScope(VD->getContext());
908  DebugVariable *DV = new DebugVariable(VD, FrameIndex);
909  Scope->AddVariable(DV);
910}
911
912/// getOrCreateScope - Returns the scope associated with the given descriptor.
913///
914DebugScope *MachineModuleInfo::getOrCreateScope(DebugInfoDesc *ScopeDesc) {
915  DebugScope *&Slot = ScopeMap[ScopeDesc];
916  if (!Slot) {
917    // FIXME - breaks down when the context is an inlined function.
918    DebugInfoDesc *ParentDesc = NULL;
919    if (BlockDesc *Block = dyn_cast<BlockDesc>(ScopeDesc)) {
920      ParentDesc = Block->getContext();
921    }
922    DebugScope *Parent = ParentDesc ? getOrCreateScope(ParentDesc) : NULL;
923    Slot = new DebugScope(Parent, ScopeDesc);
924    if (Parent) {
925      Parent->AddScope(Slot);
926    } else if (RootScope) {
927      // FIXME - Add inlined function scopes to the root so we can delete
928      // them later.  Long term, handle inlined functions properly.
929      RootScope->AddScope(Slot);
930    } else {
931      // First function is top level function.
932      RootScope = Slot;
933    }
934  }
935  return Slot;
936}
937
938//===-EH-------------------------------------------------------------------===//
939
940/// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
941/// specified MachineBasicBlock.
942LandingPadInfo &
943MachineModuleInfo::getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad) {
944  unsigned N = LandingPads.size();
945
946  for (unsigned i = 0; i < N; ++i) {
947    LandingPadInfo &LP = LandingPads[i];
948    if (LP.LandingPadBlock == LandingPad)
949      return LP;
950  }
951
952  LandingPads.push_back(LandingPadInfo(LandingPad));
953  return LandingPads[N];
954}
955
956/// addInvoke - Provide the begin and end labels of an invoke style call and
957/// associate it with a try landing pad block.
958void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad,
959                                  unsigned BeginLabel, unsigned EndLabel) {
960  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
961  LP.BeginLabels.push_back(BeginLabel);
962  LP.EndLabels.push_back(EndLabel);
963}
964
965/// addLandingPad - Provide the label of a try LandingPad block.
966///
967unsigned MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) {
968  unsigned LandingPadLabel = NextLabelID();
969  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
970  LP.LandingPadLabel = LandingPadLabel;
971  return LandingPadLabel;
972}
973
974/// addPersonality - Provide the personality function for the exception
975/// information.
976void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad,
977                                       Function *Personality) {
978  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
979  LP.Personality = Personality;
980
981  for (unsigned i = 0, e = Personalities.size(); i < e; ++i)
982    if (Personalities[i] == Personality)
983      return;
984
985  Personalities.push_back(Personality);
986}
987
988/// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
989///
990void MachineModuleInfo::addCatchTypeInfo(MachineBasicBlock *LandingPad,
991                                        std::vector<GlobalVariable *> &TyInfo) {
992  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
993  for (unsigned N = TyInfo.size(); N; --N)
994    LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
995}
996
997/// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
998///
999void MachineModuleInfo::addFilterTypeInfo(MachineBasicBlock *LandingPad,
1000                                        std::vector<GlobalVariable *> &TyInfo) {
1001  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
1002  unsigned TyInfoSize = TyInfo.size();
1003  std::vector<unsigned> IdsInFilter(TyInfoSize);
1004
1005  for (unsigned I = 0; I != TyInfoSize; ++I)
1006    IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
1007
1008  LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
1009}
1010
1011/// addCleanup - Add a cleanup action for a landing pad.
1012///
1013void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) {
1014  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
1015  LP.TypeIds.push_back(0);
1016}
1017
1018/// TidyLandingPads - Remap landing pad labels and remove any deleted landing
1019/// pads.
1020void MachineModuleInfo::TidyLandingPads() {
1021  for (unsigned i = 0; i != LandingPads.size(); ) {
1022    LandingPadInfo &LandingPad = LandingPads[i];
1023    LandingPad.LandingPadLabel = MappedLabel(LandingPad.LandingPadLabel);
1024
1025    // Special case: we *should* emit LPs with null LP MBB. This indicates
1026    // "nounwind" case.
1027    if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
1028      LandingPads.erase(LandingPads.begin() + i);
1029      continue;
1030    }
1031
1032    for (unsigned j = 0; j != LandingPads[i].BeginLabels.size(); ) {
1033      unsigned BeginLabel = MappedLabel(LandingPad.BeginLabels[j]);
1034      unsigned EndLabel = MappedLabel(LandingPad.EndLabels[j]);
1035
1036      if (!BeginLabel || !EndLabel) {
1037        LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
1038        LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
1039        continue;
1040      }
1041
1042      LandingPad.BeginLabels[j] = BeginLabel;
1043      LandingPad.EndLabels[j] = EndLabel;
1044      ++j;
1045    }
1046
1047    // Remove landing pads with no try-ranges.
1048    if (LandingPads[i].BeginLabels.empty()) {
1049      LandingPads.erase(LandingPads.begin() + i);
1050      continue;
1051    }
1052
1053    // If there is no landing pad, ensure that the list of typeids is empty.
1054    // If the only typeid is a cleanup, this is the same as having no typeids.
1055    if (!LandingPad.LandingPadBlock ||
1056        (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
1057      LandingPad.TypeIds.clear();
1058
1059    ++i;
1060  }
1061}
1062
1063/// getTypeIDFor - Return the type id for the specified typeinfo.  This is
1064/// function wide.
1065unsigned MachineModuleInfo::getTypeIDFor(GlobalVariable *TI) {
1066  for (unsigned i = 0, e = TypeInfos.size(); i != e; ++i)
1067    if (TypeInfos[i] == TI)
1068      return i + 1;
1069
1070  TypeInfos.push_back(TI);
1071  return TypeInfos.size();
1072}
1073
1074/// getFilterIDFor - Return the filter id for the specified typeinfos.  This is
1075/// function wide.
1076int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) {
1077  // If the new filter coincides with the tail of an existing filter, then
1078  // re-use the existing filter.  Folding filters more than this requires
1079  // re-ordering filters and/or their elements - probably not worth it.
1080  for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
1081       E = FilterEnds.end(); I != E; ++I) {
1082    unsigned i = *I, j = TyIds.size();
1083
1084    while (i && j)
1085      if (FilterIds[--i] != TyIds[--j])
1086        goto try_next;
1087
1088    if (!j)
1089      // The new filter coincides with range [i, end) of the existing filter.
1090      return -(1 + i);
1091
1092try_next:;
1093  }
1094
1095  // Add the new filter.
1096  int FilterID = -(1 + FilterIds.size());
1097  FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
1098
1099  for (unsigned I = 0, N = TyIds.size(); I != N; ++I)
1100    FilterIds.push_back(TyIds[I]);
1101
1102  FilterEnds.push_back(FilterIds.size());
1103  FilterIds.push_back(0); // terminator
1104  return FilterID;
1105}
1106
1107/// getPersonality - Return the personality function for the current function.
1108Function *MachineModuleInfo::getPersonality() const {
1109  // FIXME: Until PR1414 will be fixed, we're using 1 personality function per
1110  // function
1111  return !LandingPads.empty() ? LandingPads[0].Personality : NULL;
1112}
1113
1114/// getPersonalityIndex - Return unique index for current personality
1115/// function. NULL personality function should always get zero index.
1116unsigned MachineModuleInfo::getPersonalityIndex() const {
1117  const Function* Personality = NULL;
1118
1119  // Scan landing pads. If there is at least one non-NULL personality - use it.
1120  for (unsigned i = 0, e = LandingPads.size(); i != e; ++i)
1121    if (LandingPads[i].Personality) {
1122      Personality = LandingPads[i].Personality;
1123      break;
1124    }
1125
1126  for (unsigned i = 0, e = Personalities.size(); i < e; ++i)
1127    if (Personalities[i] == Personality)
1128      return i;
1129
1130  // This should never happen
1131  assert(0 && "Personality function should be set!");
1132  return 0;
1133}
1134
1135//===----------------------------------------------------------------------===//
1136/// DebugLabelFolding pass - This pass prunes out redundant labels.  This allows
1137/// a info consumer to determine if the range of two labels is empty, by seeing
1138/// if the labels map to the same reduced label.
1139
1140namespace llvm {
1141
1142struct DebugLabelFolder : public MachineFunctionPass {
1143  static char ID;
1144  DebugLabelFolder() : MachineFunctionPass((intptr_t)&ID) {}
1145
1146  virtual bool runOnMachineFunction(MachineFunction &MF);
1147  virtual const char *getPassName() const { return "Label Folder"; }
1148};
1149
1150char DebugLabelFolder::ID = 0;
1151
1152bool DebugLabelFolder::runOnMachineFunction(MachineFunction &MF) {
1153  // Get machine module info.
1154  MachineModuleInfo *MMI = getAnalysisToUpdate<MachineModuleInfo>();
1155  if (!MMI) return false;
1156
1157  // Track if change is made.
1158  bool MadeChange = false;
1159  // No prior label to begin.
1160  unsigned PriorLabel = 0;
1161
1162  // Iterate through basic blocks.
1163  for (MachineFunction::iterator BB = MF.begin(), E = MF.end();
1164       BB != E; ++BB) {
1165    // Iterate through instructions.
1166    for (MachineBasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
1167      // Is it a label.
1168      if (I->isDebugLabel()) {
1169        // The label ID # is always operand #0, an immediate.
1170        unsigned NextLabel = I->getOperand(0).getImm();
1171
1172        // If there was an immediate prior label.
1173        if (PriorLabel) {
1174          // Remap the current label to prior label.
1175          MMI->RemapLabel(NextLabel, PriorLabel);
1176          // Delete the current label.
1177          I = BB->erase(I);
1178          // Indicate a change has been made.
1179          MadeChange = true;
1180          continue;
1181        } else {
1182          // Start a new round.
1183          PriorLabel = NextLabel;
1184        }
1185       } else {
1186        // No consecutive labels.
1187        PriorLabel = 0;
1188      }
1189
1190      ++I;
1191    }
1192  }
1193
1194  return MadeChange;
1195}
1196
1197FunctionPass *createDebugLabelFoldingPass() { return new DebugLabelFolder(); }
1198
1199}
1200