1//===-- llvm/CodeGen/MachineModuleInfo.h ------------------------*- 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// Collect meta information for a module.  This information should be in a
11// neutral form that can be used by different debugging and exception handling
12// schemes.
13//
14// The organization of information is primarily clustered around the source
15// compile units.  The main exception is source line correspondence where
16// inlining may interleave code from various compile units.
17//
18// The following information can be retrieved from the MachineModuleInfo.
19//
20//  -- Source directories - Directories are uniqued based on their canonical
21//     string and assigned a sequential numeric ID (base 1.)
22//  -- Source files - Files are also uniqued based on their name and directory
23//     ID.  A file ID is sequential number (base 1.)
24//  -- Source line correspondence - A vector of file ID, line#, column# triples.
25//     A DEBUG_LOCATION instruction is generated  by the DAG Legalizer
26//     corresponding to each entry in the source line list.  This allows a debug
27//     emitter to generate labels referenced by debug information tables.
28//
29//===----------------------------------------------------------------------===//
30
31#ifndef LLVM_CODEGEN_MACHINEMODULEINFO_H
32#define LLVM_CODEGEN_MACHINEMODULEINFO_H
33
34#include "llvm/Pass.h"
35#include "llvm/GlobalValue.h"
36#include "llvm/Metadata.h"
37#include "llvm/MC/MachineLocation.h"
38#include "llvm/MC/MCContext.h"
39#include "llvm/Support/Dwarf.h"
40#include "llvm/Support/DebugLoc.h"
41#include "llvm/Support/ValueHandle.h"
42#include "llvm/Support/DataTypes.h"
43#include "llvm/ADT/DenseMap.h"
44#include "llvm/ADT/PointerIntPair.h"
45#include "llvm/ADT/SmallPtrSet.h"
46#include "llvm/ADT/SmallVector.h"
47
48namespace llvm {
49
50//===----------------------------------------------------------------------===//
51// Forward declarations.
52class Constant;
53class GlobalVariable;
54class MDNode;
55class MMIAddrLabelMap;
56class MachineBasicBlock;
57class MachineFunction;
58class Module;
59class PointerType;
60class StructType;
61
62//===----------------------------------------------------------------------===//
63/// LandingPadInfo - This structure is used to retain landing pad info for
64/// the current function.
65///
66struct LandingPadInfo {
67  MachineBasicBlock *LandingPadBlock;    // Landing pad block.
68  SmallVector<MCSymbol*, 1> BeginLabels; // Labels prior to invoke.
69  SmallVector<MCSymbol*, 1> EndLabels;   // Labels after invoke.
70  MCSymbol *LandingPadLabel;             // Label at beginning of landing pad.
71  const Function *Personality;           // Personality function.
72  std::vector<int> TypeIds;              // List of type ids (filters negative)
73
74  explicit LandingPadInfo(MachineBasicBlock *MBB)
75    : LandingPadBlock(MBB), LandingPadLabel(0), Personality(0) {}
76};
77
78//===----------------------------------------------------------------------===//
79/// MachineModuleInfoImpl - This class can be derived from and used by targets
80/// to hold private target-specific information for each Module.  Objects of
81/// type are accessed/created with MMI::getInfo and destroyed when the
82/// MachineModuleInfo is destroyed.
83///
84class MachineModuleInfoImpl {
85public:
86  typedef PointerIntPair<MCSymbol*, 1, bool> StubValueTy;
87  virtual ~MachineModuleInfoImpl();
88  typedef std::vector<std::pair<MCSymbol*, StubValueTy> > SymbolListTy;
89protected:
90  static SymbolListTy GetSortedStubs(const DenseMap<MCSymbol*, StubValueTy>&);
91};
92
93//===----------------------------------------------------------------------===//
94/// MachineModuleInfo - This class contains meta information specific to a
95/// module.  Queries can be made by different debugging and exception handling
96/// schemes and reformated for specific use.
97///
98class MachineModuleInfo : public ImmutablePass {
99  /// Context - This is the MCContext used for the entire code generator.
100  MCContext Context;
101
102  /// TheModule - This is the LLVM Module being worked on.
103  const Module *TheModule;
104
105  /// ObjFileMMI - This is the object-file-format-specific implementation of
106  /// MachineModuleInfoImpl, which lets targets accumulate whatever info they
107  /// want.
108  MachineModuleInfoImpl *ObjFileMMI;
109
110  /// FrameMoves - List of moves done by a function's prolog.  Used to construct
111  /// frame maps by debug and exception handling consumers.
112  std::vector<MachineMove> FrameMoves;
113
114  /// CompactUnwindEncoding - If the target supports it, this is the compact
115  /// unwind encoding. It replaces a function's CIE and FDE.
116  uint32_t CompactUnwindEncoding;
117
118  /// LandingPads - List of LandingPadInfo describing the landing pad
119  /// information in the current function.
120  std::vector<LandingPadInfo> LandingPads;
121
122  /// LPadToCallSiteMap - Map a landing pad's EH symbol to the call site
123  /// indexes.
124  DenseMap<MCSymbol*, SmallVector<unsigned, 4> > LPadToCallSiteMap;
125
126  /// CallSiteMap - Map of invoke call site index values to associated begin
127  /// EH_LABEL for the current function.
128  DenseMap<MCSymbol*, unsigned> CallSiteMap;
129
130  /// CurCallSite - The current call site index being processed, if any. 0 if
131  /// none.
132  unsigned CurCallSite;
133
134  /// TypeInfos - List of C++ TypeInfo used in the current function.
135  std::vector<const GlobalVariable *> TypeInfos;
136
137  /// FilterIds - List of typeids encoding filters used in the current function.
138  std::vector<unsigned> FilterIds;
139
140  /// FilterEnds - List of the indices in FilterIds corresponding to filter
141  /// terminators.
142  std::vector<unsigned> FilterEnds;
143
144  /// Personalities - Vector of all personality functions ever seen. Used to
145  /// emit common EH frames.
146  std::vector<const Function *> Personalities;
147
148  /// UsedFunctions - The functions in the @llvm.used list in a more easily
149  /// searchable format.  This does not include the functions in
150  /// llvm.compiler.used.
151  SmallPtrSet<const Function *, 32> UsedFunctions;
152
153  /// AddrLabelSymbols - This map keeps track of which symbol is being used for
154  /// the specified basic block's address of label.
155  MMIAddrLabelMap *AddrLabelSymbols;
156
157  bool CallsEHReturn;
158  bool CallsUnwindInit;
159
160  /// DbgInfoAvailable - True if debugging information is available
161  /// in this module.
162  bool DbgInfoAvailable;
163
164  /// UsesVAFloatArgument - True if this module calls VarArg function with
165  /// floating-point arguments.  This is used to emit an undefined reference
166  /// to _fltused on Windows targets.
167  bool UsesVAFloatArgument;
168
169public:
170  static char ID; // Pass identification, replacement for typeid
171
172  typedef std::pair<unsigned, DebugLoc> UnsignedDebugLocPair;
173  typedef SmallVector<std::pair<TrackingVH<MDNode>, UnsignedDebugLocPair>, 4>
174    VariableDbgInfoMapTy;
175  VariableDbgInfoMapTy VariableDbgInfo;
176
177  MachineModuleInfo();  // DUMMY CONSTRUCTOR, DO NOT CALL.
178  // Real constructor.
179  MachineModuleInfo(const MCAsmInfo &MAI, const MCRegisterInfo &MRI,
180                    const MCObjectFileInfo *MOFI);
181  ~MachineModuleInfo();
182
183  bool doInitialization();
184  bool doFinalization();
185
186  /// EndFunction - Discard function meta information.
187  ///
188  void EndFunction();
189
190  const MCContext &getContext() const { return Context; }
191  MCContext &getContext() { return Context; }
192
193  void setModule(const Module *M) { TheModule = M; }
194  const Module *getModule() const { return TheModule; }
195
196  /// getInfo - Keep track of various per-function pieces of information for
197  /// backends that would like to do so.
198  ///
199  template<typename Ty>
200  Ty &getObjFileInfo() {
201    if (ObjFileMMI == 0)
202      ObjFileMMI = new Ty(*this);
203    return *static_cast<Ty*>(ObjFileMMI);
204  }
205
206  template<typename Ty>
207  const Ty &getObjFileInfo() const {
208    return const_cast<MachineModuleInfo*>(this)->getObjFileInfo<Ty>();
209  }
210
211  /// AnalyzeModule - Scan the module for global debug information.
212  ///
213  void AnalyzeModule(const Module &M);
214
215  /// hasDebugInfo - Returns true if valid debug info is present.
216  ///
217  bool hasDebugInfo() const { return DbgInfoAvailable; }
218  void setDebugInfoAvailability(bool avail) { DbgInfoAvailable = avail; }
219
220  bool callsEHReturn() const { return CallsEHReturn; }
221  void setCallsEHReturn(bool b) { CallsEHReturn = b; }
222
223  bool callsUnwindInit() const { return CallsUnwindInit; }
224  void setCallsUnwindInit(bool b) { CallsUnwindInit = b; }
225
226  bool usesVAFloatArgument() const {
227    return UsesVAFloatArgument;
228  }
229
230  void setUsesVAFloatArgument(bool b) {
231    UsesVAFloatArgument = b;
232  }
233
234  /// getFrameMoves - Returns a reference to a list of moves done in the current
235  /// function's prologue.  Used to construct frame maps for debug and exception
236  /// handling comsumers.
237  std::vector<MachineMove> &getFrameMoves() { return FrameMoves; }
238
239  /// getCompactUnwindEncoding - Returns the compact unwind encoding for a
240  /// function if the target supports the encoding. This encoding replaces a
241  /// function's CIE and FDE.
242  uint32_t getCompactUnwindEncoding() const { return CompactUnwindEncoding; }
243
244  /// setCompactUnwindEncoding - Set the compact unwind encoding for a function
245  /// if the target supports the encoding.
246  void setCompactUnwindEncoding(uint32_t Enc) { CompactUnwindEncoding = Enc; }
247
248  /// getAddrLabelSymbol - Return the symbol to be used for the specified basic
249  /// block when its address is taken.  This cannot be its normal LBB label
250  /// because the block may be accessed outside its containing function.
251  MCSymbol *getAddrLabelSymbol(const BasicBlock *BB);
252
253  /// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified
254  /// basic block when its address is taken.  If other blocks were RAUW'd to
255  /// this one, we may have to emit them as well, return the whole set.
256  std::vector<MCSymbol*> getAddrLabelSymbolToEmit(const BasicBlock *BB);
257
258  /// takeDeletedSymbolsForFunction - If the specified function has had any
259  /// references to address-taken blocks generated, but the block got deleted,
260  /// return the symbol now so we can emit it.  This prevents emitting a
261  /// reference to a symbol that has no definition.
262  void takeDeletedSymbolsForFunction(const Function *F,
263                                     std::vector<MCSymbol*> &Result);
264
265
266  //===- EH ---------------------------------------------------------------===//
267
268  /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
269  /// specified MachineBasicBlock.
270  LandingPadInfo &getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad);
271
272  /// addInvoke - Provide the begin and end labels of an invoke style call and
273  /// associate it with a try landing pad block.
274  void addInvoke(MachineBasicBlock *LandingPad,
275                 MCSymbol *BeginLabel, MCSymbol *EndLabel);
276
277  /// addLandingPad - Add a new panding pad.  Returns the label ID for the
278  /// landing pad entry.
279  MCSymbol *addLandingPad(MachineBasicBlock *LandingPad);
280
281  /// addPersonality - Provide the personality function for the exception
282  /// information.
283  void addPersonality(MachineBasicBlock *LandingPad,
284                      const Function *Personality);
285
286  /// getPersonalityIndex - Get index of the current personality function inside
287  /// Personalitites array
288  unsigned getPersonalityIndex() const;
289
290  /// getPersonalities - Return array of personality functions ever seen.
291  const std::vector<const Function *>& getPersonalities() const {
292    return Personalities;
293  }
294
295  /// isUsedFunction - Return true if the functions in the llvm.used list.  This
296  /// does not return true for things in llvm.compiler.used unless they are also
297  /// in llvm.used.
298  bool isUsedFunction(const Function *F) {
299    return UsedFunctions.count(F);
300  }
301
302  /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
303  ///
304  void addCatchTypeInfo(MachineBasicBlock *LandingPad,
305                        ArrayRef<const GlobalVariable *> TyInfo);
306
307  /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
308  ///
309  void addFilterTypeInfo(MachineBasicBlock *LandingPad,
310                         ArrayRef<const GlobalVariable *> TyInfo);
311
312  /// addCleanup - Add a cleanup action for a landing pad.
313  ///
314  void addCleanup(MachineBasicBlock *LandingPad);
315
316  /// getTypeIDFor - Return the type id for the specified typeinfo.  This is
317  /// function wide.
318  unsigned getTypeIDFor(const GlobalVariable *TI);
319
320  /// getFilterIDFor - Return the id of the filter encoded by TyIds.  This is
321  /// function wide.
322  int getFilterIDFor(std::vector<unsigned> &TyIds);
323
324  /// TidyLandingPads - Remap landing pad labels and remove any deleted landing
325  /// pads.
326  void TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap = 0);
327
328  /// getLandingPads - Return a reference to the landing pad info for the
329  /// current function.
330  const std::vector<LandingPadInfo> &getLandingPads() const {
331    return LandingPads;
332  }
333
334  /// setCallSiteLandingPad - Map the landing pad's EH symbol to the call
335  /// site indexes.
336  void setCallSiteLandingPad(MCSymbol *Sym, ArrayRef<unsigned> Sites);
337
338  /// getCallSiteLandingPad - Get the call site indexes for a landing pad EH
339  /// symbol.
340  SmallVectorImpl<unsigned> &getCallSiteLandingPad(MCSymbol *Sym) {
341    assert(hasCallSiteLandingPad(Sym) &&
342           "missing call site number for landing pad!");
343    return LPadToCallSiteMap[Sym];
344  }
345
346  /// hasCallSiteLandingPad - Return true if the landing pad Eh symbol has an
347  /// associated call site.
348  bool hasCallSiteLandingPad(MCSymbol *Sym) {
349    return !LPadToCallSiteMap[Sym].empty();
350  }
351
352  /// setCallSiteBeginLabel - Map the begin label for a call site.
353  void setCallSiteBeginLabel(MCSymbol *BeginLabel, unsigned Site) {
354    CallSiteMap[BeginLabel] = Site;
355  }
356
357  /// getCallSiteBeginLabel - Get the call site number for a begin label.
358  unsigned getCallSiteBeginLabel(MCSymbol *BeginLabel) {
359    assert(hasCallSiteBeginLabel(BeginLabel) &&
360           "Missing call site number for EH_LABEL!");
361    return CallSiteMap[BeginLabel];
362  }
363
364  /// hasCallSiteBeginLabel - Return true if the begin label has a call site
365  /// number associated with it.
366  bool hasCallSiteBeginLabel(MCSymbol *BeginLabel) {
367    return CallSiteMap[BeginLabel] != 0;
368  }
369
370  /// setCurrentCallSite - Set the call site currently being processed.
371  void setCurrentCallSite(unsigned Site) { CurCallSite = Site; }
372
373  /// getCurrentCallSite - Get the call site currently being processed, if any.
374  /// return zero if none.
375  unsigned getCurrentCallSite(void) { return CurCallSite; }
376
377  /// getTypeInfos - Return a reference to the C++ typeinfo for the current
378  /// function.
379  const std::vector<const GlobalVariable *> &getTypeInfos() const {
380    return TypeInfos;
381  }
382
383  /// getFilterIds - Return a reference to the typeids encoding filters used in
384  /// the current function.
385  const std::vector<unsigned> &getFilterIds() const {
386    return FilterIds;
387  }
388
389  /// getPersonality - Return a personality function if available.  The presence
390  /// of one is required to emit exception handling info.
391  const Function *getPersonality() const;
392
393  /// setVariableDbgInfo - Collect information used to emit debugging
394  /// information of a variable.
395  void setVariableDbgInfo(MDNode *N, unsigned Slot, DebugLoc Loc) {
396    VariableDbgInfo.push_back(std::make_pair(N, std::make_pair(Slot, Loc)));
397  }
398
399  VariableDbgInfoMapTy &getVariableDbgInfo() { return VariableDbgInfo; }
400
401}; // End class MachineModuleInfo
402
403} // End llvm namespace
404
405#endif
406