MachineModuleInfo.h revision 11d53c129fc9c2a4510605ec0a1696f58750af52 
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/CodeGen/MachineLocation.h"
38#include "llvm/MC/MCContext.h"
39#include "llvm/Support/Dwarf.h"
40#include "llvm/Support/ValueHandle.h"
41#include "llvm/System/DataTypes.h"
42#include "llvm/ADT/DenseMap.h"
43#include "llvm/ADT/PointerIntPair.h"
44#include "llvm/ADT/SmallPtrSet.h"
45#include "llvm/ADT/SmallVector.h"
46
47namespace llvm {
48
49//===----------------------------------------------------------------------===//
50// Forward declarations.
51class Constant;
52class GlobalVariable;
53class MDNode;
54class MachineBasicBlock;
55class MachineFunction;
56class Module;
57class PointerType;
58class StructType;
59
60/// MachineModuleInfoImpl - This class can be derived from and used by targets
61/// to hold private target-specific information for each Module.  Objects of
62/// type are accessed/created with MMI::getInfo and destroyed when the
63/// MachineModuleInfo is destroyed.
64class MachineModuleInfoImpl {
65public:
66  typedef PointerIntPair<MCSymbol*, 1, bool> StubValueTy;
67  virtual ~MachineModuleInfoImpl();
68  typedef std::vector<std::pair<MCSymbol*, StubValueTy> > SymbolListTy;
69protected:
70  static SymbolListTy GetSortedStubs(const DenseMap<MCSymbol*, StubValueTy>&);
71};
72
73
74
75//===----------------------------------------------------------------------===//
76/// LandingPadInfo - This structure is used to retain landing pad info for
77/// the current function.
78///
79struct LandingPadInfo {
80  MachineBasicBlock *LandingPadBlock;   // Landing pad block.
81  SmallVector<unsigned, 1> BeginLabels; // Labels prior to invoke.
82  SmallVector<unsigned, 1> EndLabels;   // Labels after invoke.
83  unsigned LandingPadLabel;             // Label at beginning of landing pad.
84  Function *Personality;                // Personality function.
85  std::vector<int> TypeIds;             // List of type ids (filters negative)
86
87  explicit LandingPadInfo(MachineBasicBlock *MBB)
88  : LandingPadBlock(MBB)
89  , LandingPadLabel(0)
90  , Personality(NULL)
91  {}
92};
93
94//===----------------------------------------------------------------------===//
95/// MachineModuleInfo - This class contains meta information specific to a
96/// module.  Queries can be made by different debugging and exception handling
97/// schemes and reformated for specific use.
98///
99class MachineModuleInfo : public ImmutablePass {
100  /// Context - This is the MCContext used for the entire code generator.
101  MCContext Context;
102
103  /// ObjFileMMI - This is the object-file-format-specific implementation of
104  /// MachineModuleInfoImpl, which lets targets accumulate whatever info they
105  /// want.
106  MachineModuleInfoImpl *ObjFileMMI;
107
108  // LabelIDList - One entry per assigned label.  Normally the entry is equal to
109  // the list index(+1).  If the entry is zero then the label has been deleted.
110  // Any other value indicates the label has been deleted by is mapped to
111  // another label.
112  std::vector<unsigned> LabelIDList;
113
114  // FrameMoves - List of moves done by a function's prolog.  Used to construct
115  // frame maps by debug and exception handling consumers.
116  std::vector<MachineMove> FrameMoves;
117
118  // LandingPads - List of LandingPadInfo describing the landing pad information
119  // in the current function.
120  std::vector<LandingPadInfo> LandingPads;
121
122  // Map of invoke call site index values to associated begin EH_LABEL for
123  // the current function.
124  DenseMap<unsigned, unsigned> CallSiteMap;
125
126  // The current call site index being processed, if any. 0 if none.
127  unsigned CurCallSite;
128
129  // TypeInfos - List of C++ TypeInfo used in the current function.
130  //
131  std::vector<GlobalVariable *> TypeInfos;
132
133  // FilterIds - List of typeids encoding filters used in the current function.
134  //
135  std::vector<unsigned> FilterIds;
136
137  // FilterEnds - List of the indices in FilterIds corresponding to filter
138  // terminators.
139  //
140  std::vector<unsigned> FilterEnds;
141
142  // Personalities - Vector of all personality functions ever seen. Used to emit
143  // common EH frames.
144  std::vector<Function *> Personalities;
145
146  /// UsedFunctions - The functions in the @llvm.used list in a more easily
147  /// searchable format.  This does not include the functions in
148  /// llvm.compiler.used.
149  SmallPtrSet<const Function *, 32> UsedFunctions;
150
151  bool CallsEHReturn;
152  bool CallsUnwindInit;
153
154  /// DbgInfoAvailable - True if debugging information is available
155  /// in this module.
156  bool DbgInfoAvailable;
157
158public:
159  static char ID; // Pass identification, replacement for typeid
160
161  typedef std::pair<unsigned, TrackingVH<MDNode> > UnsignedAndMDNodePair;
162  typedef SmallVector< std::pair<TrackingVH<MDNode>, UnsignedAndMDNodePair>, 4>
163    VariableDbgInfoMapTy;
164  VariableDbgInfoMapTy VariableDbgInfo;
165
166  MachineModuleInfo();  // DUMMY CONSTRUCTOR, DO NOT CALL.
167  MachineModuleInfo(const MCAsmInfo &MAI);  // Real constructor.
168  ~MachineModuleInfo();
169
170  bool doInitialization();
171  bool doFinalization();
172
173  /// EndFunction - Discard function meta information.
174  ///
175  void EndFunction();
176
177  const MCContext &getContext() const { return Context; }
178  MCContext &getContext() { return Context; }
179
180  /// getInfo - Keep track of various per-function pieces of information for
181  /// backends that would like to do so.
182  ///
183  template<typename Ty>
184  Ty &getObjFileInfo() {
185    if (ObjFileMMI == 0)
186      ObjFileMMI = new Ty(*this);
187    return *static_cast<Ty*>(ObjFileMMI);
188  }
189
190  template<typename Ty>
191  const Ty &getObjFileInfo() const {
192    return const_cast<MachineModuleInfo*>(this)->getObjFileInfo<Ty>();
193  }
194
195  /// AnalyzeModule - Scan the module for global debug information.
196  ///
197  void AnalyzeModule(Module &M);
198
199  /// hasDebugInfo - Returns true if valid debug info is present.
200  ///
201  bool hasDebugInfo() const { return DbgInfoAvailable; }
202  void setDebugInfoAvailability(bool avail) { DbgInfoAvailable = true; }
203
204  bool callsEHReturn() const { return CallsEHReturn; }
205  void setCallsEHReturn(bool b) { CallsEHReturn = b; }
206
207  bool callsUnwindInit() const { return CallsUnwindInit; }
208  void setCallsUnwindInit(bool b) { CallsUnwindInit = b; }
209
210  /// NextLabelID - Return the next unique label id.
211  ///
212  unsigned NextLabelID() {
213    unsigned ID = (unsigned)LabelIDList.size() + 1;
214    LabelIDList.push_back(ID);
215    return ID;
216  }
217
218  /// InvalidateLabel - Inhibit use of the specified label # from
219  /// MachineModuleInfo, for example because the code was deleted.
220  void InvalidateLabel(unsigned LabelID) {
221    // Remap to zero to indicate deletion.
222    assert(0 < LabelID && LabelID <= LabelIDList.size() &&
223           "Old label ID out of range.");
224    LabelIDList[LabelID - 1] = 0;
225  }
226
227  /// isLabelDeleted - Return true if the label was deleted.
228  /// FIXME: This should eventually be eliminated and use the 'is emitted' bit
229  /// on MCSymbol.
230  bool isLabelDeleted(unsigned LabelID) const {
231    assert(LabelID <= LabelIDList.size() && "Debug label ID out of range.");
232    return LabelID == 0 || LabelIDList[LabelID - 1] == 0;
233  }
234
235  /// getFrameMoves - Returns a reference to a list of moves done in the current
236  /// function's prologue.  Used to construct frame maps for debug and exception
237  /// handling comsumers.
238  std::vector<MachineMove> &getFrameMoves() { return FrameMoves; }
239
240  //===-EH-----------------------------------------------------------------===//
241
242  /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
243  /// specified MachineBasicBlock.
244  LandingPadInfo &getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad);
245
246  /// addInvoke - Provide the begin and end labels of an invoke style call and
247  /// associate it with a try landing pad block.
248  void addInvoke(MachineBasicBlock *LandingPad, unsigned BeginLabel,
249                                                unsigned EndLabel);
250
251  /// addLandingPad - Add a new panding pad.  Returns the label ID for the
252  /// landing pad entry.
253  unsigned addLandingPad(MachineBasicBlock *LandingPad);
254
255  /// addPersonality - Provide the personality function for the exception
256  /// information.
257  void addPersonality(MachineBasicBlock *LandingPad, Function *Personality);
258
259  /// getPersonalityIndex - Get index of the current personality function inside
260  /// Personalitites array
261  unsigned getPersonalityIndex() const;
262
263  /// getPersonalities - Return array of personality functions ever seen.
264  const std::vector<Function *>& getPersonalities() const {
265    return Personalities;
266  }
267
268  /// isUsedFunction - Return true if the functions in the llvm.used list.  This
269  /// does not return true for things in llvm.compiler.used unless they are also
270  /// in llvm.used.
271  bool isUsedFunction(const Function *F) {
272    return UsedFunctions.count(F);
273  }
274
275  /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
276  ///
277  void addCatchTypeInfo(MachineBasicBlock *LandingPad,
278                        std::vector<GlobalVariable *> &TyInfo);
279
280  /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
281  ///
282  void addFilterTypeInfo(MachineBasicBlock *LandingPad,
283                         std::vector<GlobalVariable *> &TyInfo);
284
285  /// addCleanup - Add a cleanup action for a landing pad.
286  ///
287  void addCleanup(MachineBasicBlock *LandingPad);
288
289  /// getTypeIDFor - Return the type id for the specified typeinfo.  This is
290  /// function wide.
291  unsigned getTypeIDFor(GlobalVariable *TI);
292
293  /// getFilterIDFor - Return the id of the filter encoded by TyIds.  This is
294  /// function wide.
295  int getFilterIDFor(std::vector<unsigned> &TyIds);
296
297  /// TidyLandingPads - Remap landing pad labels and remove any deleted landing
298  /// pads.
299  void TidyLandingPads();
300
301  /// getLandingPads - Return a reference to the landing pad info for the
302  /// current function.
303  const std::vector<LandingPadInfo> &getLandingPads() const {
304    return LandingPads;
305  }
306
307  /// setCallSiteBeginLabel - Map the begin label for a call site
308  void setCallSiteBeginLabel(unsigned BeginLabel, unsigned Site) {
309    CallSiteMap[BeginLabel] = Site;
310  }
311
312  /// getCallSiteBeginLabel - Get the call site number for a begin label
313  unsigned getCallSiteBeginLabel(unsigned BeginLabel) {
314    assert(CallSiteMap.count(BeginLabel) &&
315           "Missing call site number for EH_LABEL!");
316    return CallSiteMap[BeginLabel];
317  }
318
319  /// setCurrentCallSite - Set the call site currently being processed.
320  void setCurrentCallSite(unsigned Site) { CurCallSite = Site; }
321
322  /// getCurrentCallSite - Get the call site currently being processed, if any.
323  /// return zero if none.
324  unsigned getCurrentCallSite(void) { return CurCallSite; }
325
326  /// getTypeInfos - Return a reference to the C++ typeinfo for the current
327  /// function.
328  const std::vector<GlobalVariable *> &getTypeInfos() const {
329    return TypeInfos;
330  }
331
332  /// getFilterIds - Return a reference to the typeids encoding filters used in
333  /// the current function.
334  const std::vector<unsigned> &getFilterIds() const {
335    return FilterIds;
336  }
337
338  /// getPersonality - Return a personality function if available.  The presence
339  /// of one is required to emit exception handling info.
340  Function *getPersonality() const;
341
342  /// setVariableDbgInfo - Collect information used to emit debugging information
343  /// of a variable.
344  void setVariableDbgInfo(MDNode *N, unsigned Slot, MDNode *Scope) {
345    VariableDbgInfo.push_back(std::make_pair(N, std::make_pair(Slot, Scope)));
346  }
347
348  VariableDbgInfoMapTy &getVariableDbgInfo() {  return VariableDbgInfo;  }
349
350}; // End class MachineModuleInfo
351
352} // End llvm namespace
353
354#endif
355