Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 1 | //===- LexicalScopes.cpp - Collecting lexical scope info -*- 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 | // This file implements LexicalScopes analysis. |
| 11 | // |
| 12 | // This pass collects lexical scope information and maps machine instructions |
| 13 | // to respective lexical scopes. |
| 14 | // |
| 15 | //===----------------------------------------------------------------------===// |
| 16 | |
| 17 | #ifndef LLVM_CODEGEN_LEXICALSCOPES_H |
| 18 | #define LLVM_CODEGEN_LEXICALSCOPES_H |
| 19 | |
| 20 | #include "llvm/Metadata.h" |
Devang Patel | cd9f6c5 | 2011-08-12 18:10:19 +0000 | [diff] [blame] | 21 | #include "llvm/ADT/ArrayRef.h" |
Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 22 | #include "llvm/ADT/DenseMap.h" |
| 23 | #include "llvm/ADT/SmallPtrSet.h" |
| 24 | #include "llvm/ADT/SmallVector.h" |
| 25 | #include "llvm/Support/DebugLoc.h" |
| 26 | #include "llvm/Support/ValueHandle.h" |
| 27 | #include <utility> |
| 28 | namespace llvm { |
| 29 | |
| 30 | class MachineInstr; |
| 31 | class MachineBasicBlock; |
| 32 | class MachineFunction; |
| 33 | class LexicalScope; |
| 34 | |
| 35 | //===----------------------------------------------------------------------===// |
| 36 | /// InsnRange - This is used to track range of instructions with identical |
| 37 | /// lexical scope. |
| 38 | /// |
| 39 | typedef std::pair<const MachineInstr *, const MachineInstr *> InsnRange; |
| 40 | |
| 41 | //===----------------------------------------------------------------------===// |
| 42 | /// LexicalScopes - This class provides interface to collect and use lexical |
| 43 | /// scoping information from machine instruction. |
| 44 | /// |
| 45 | class LexicalScopes { |
| 46 | public: |
| 47 | LexicalScopes() : MF(NULL), CurrentFnLexicalScope(NULL) { } |
Nick Lewycky | 2fc75d5 | 2011-08-12 00:32:15 +0000 | [diff] [blame] | 48 | virtual ~LexicalScopes(); |
Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 49 | |
| 50 | /// initialize - Scan machine function and constuct lexical scope nest. |
| 51 | virtual void initialize(const MachineFunction &); |
| 52 | |
| 53 | /// releaseMemory - release memory. |
| 54 | virtual void releaseMemory(); |
| 55 | |
| 56 | /// empty - Return true if there is any lexical scope information available. |
| 57 | bool empty() { return CurrentFnLexicalScope == NULL; } |
| 58 | |
| 59 | /// isCurrentFunctionScope - Return true if given lexical scope represents |
| 60 | /// current function. |
| 61 | bool isCurrentFunctionScope(const LexicalScope *LS) { |
| 62 | return LS == CurrentFnLexicalScope; |
| 63 | } |
| 64 | |
| 65 | /// getCurrentFunctionScope - Return lexical scope for the current function. |
| 66 | LexicalScope *getCurrentFunctionScope() const { return CurrentFnLexicalScope;} |
| 67 | |
Devang Patel | 5bc942c | 2011-08-10 23:58:09 +0000 | [diff] [blame] | 68 | /// getMachineBasicBlocks - Populate given set using machine basic blocks |
| 69 | /// which have machine instructions that belong to lexical scope identified by |
Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 70 | /// DebugLoc. |
| 71 | void getMachineBasicBlocks(DebugLoc DL, |
| 72 | SmallPtrSet<const MachineBasicBlock*, 4> &MBBs); |
| 73 | |
| 74 | /// dominates - Return true if DebugLoc's lexical scope dominates at least one |
| 75 | /// machine instruction's lexical scope in a given machine basic block. |
| 76 | bool dominates(DebugLoc DL, MachineBasicBlock *MBB); |
| 77 | |
| 78 | /// findLexicalScope - Find lexical scope, either regular or inlined, for the |
| 79 | /// given DebugLoc. Return NULL if not found. |
| 80 | LexicalScope *findLexicalScope(DebugLoc DL); |
| 81 | |
| 82 | /// getAbstractScopesList - Return a reference to list of abstract scopes. |
Devang Patel | cd9f6c5 | 2011-08-12 18:10:19 +0000 | [diff] [blame] | 83 | ArrayRef<LexicalScope *> getAbstractScopesList() const { |
Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 84 | return AbstractScopesList; |
| 85 | } |
| 86 | |
| 87 | /// findAbstractScope - Find an abstract scope or return NULL. |
| 88 | LexicalScope *findAbstractScope(const MDNode *N) { |
| 89 | return AbstractScopeMap.lookup(N); |
| 90 | } |
| 91 | |
| 92 | /// findInlinedScope - Find an inlined scope for the given DebugLoc or return |
| 93 | /// NULL. |
| 94 | LexicalScope *findInlinedScope(DebugLoc DL) { |
| 95 | return InlinedLexicalScopeMap.lookup(DL); |
| 96 | } |
| 97 | |
| 98 | /// findLexicalScope - Find regular lexical scope or return NULL. |
| 99 | LexicalScope *findLexicalScope(const MDNode *N) { |
| 100 | return LexicalScopeMap.lookup(N); |
| 101 | } |
| 102 | |
| 103 | /// dump - Print data structures to dbgs(). |
| 104 | void dump(); |
| 105 | |
| 106 | private: |
| 107 | |
| 108 | /// getOrCreateLexicalScope - Find lexical scope for the given DebugLoc. If |
| 109 | /// not available then create new lexical scope. |
| 110 | LexicalScope *getOrCreateLexicalScope(DebugLoc DL); |
| 111 | |
| 112 | /// getOrCreateRegularScope - Find or create a regular lexical scope. |
| 113 | LexicalScope *getOrCreateRegularScope(MDNode *Scope); |
| 114 | |
| 115 | /// getOrCreateInlinedScope - Find or create an inlined lexical scope. |
| 116 | LexicalScope *getOrCreateInlinedScope(MDNode *Scope, MDNode *InlinedAt); |
| 117 | |
| 118 | /// getOrCreateAbstractScope - Find or create an abstract lexical scope. |
| 119 | LexicalScope *getOrCreateAbstractScope(const MDNode *N); |
| 120 | |
| 121 | /// extractLexicalScopes - Extract instruction ranges for each lexical scopes |
| 122 | /// for the given machine function. |
| 123 | void extractLexicalScopes(SmallVectorImpl<InsnRange> &MIRanges, |
| 124 | DenseMap<const MachineInstr *, LexicalScope *> &M); |
| 125 | void constructScopeNest(LexicalScope *Scope); |
| 126 | void assignInstructionRanges(SmallVectorImpl<InsnRange> &MIRanges, |
| 127 | DenseMap<const MachineInstr *, LexicalScope *> &M); |
| 128 | |
| 129 | private: |
| 130 | const MachineFunction *MF; |
| 131 | |
| 132 | /// LexicalScopeMap - Tracks the scopes in the current function. Owns the |
| 133 | /// contained LexicalScope*s. |
| 134 | DenseMap<const MDNode *, LexicalScope *> LexicalScopeMap; |
| 135 | |
| 136 | /// InlinedLexicalScopeMap - Tracks inlined function scopes in current function. |
| 137 | DenseMap<DebugLoc, LexicalScope *> InlinedLexicalScopeMap; |
| 138 | |
| 139 | /// AbstractScopeMap - These scopes are not included LexicalScopeMap. |
| 140 | /// AbstractScopes owns its LexicalScope*s. |
| 141 | DenseMap<const MDNode *, LexicalScope *> AbstractScopeMap; |
| 142 | |
| 143 | /// AbstractScopesList - Tracks abstract scopes constructed while processing |
| 144 | /// a function. |
| 145 | SmallVector<LexicalScope *, 4>AbstractScopesList; |
| 146 | |
| 147 | /// CurrentFnLexicalScope - Top level scope for the current function. |
| 148 | /// |
| 149 | LexicalScope *CurrentFnLexicalScope; |
| 150 | }; |
| 151 | |
| 152 | //===----------------------------------------------------------------------===// |
| 153 | /// LexicalScope - This class is used to track scope information. |
| 154 | /// |
| 155 | class LexicalScope { |
David Blaikie | 2d24e2a | 2011-12-20 02:50:00 +0000 | [diff] [blame^] | 156 | virtual void anchor(); |
Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 157 | |
| 158 | public: |
| 159 | LexicalScope(LexicalScope *P, const MDNode *D, const MDNode *I, bool A) |
| 160 | : Parent(P), Desc(D), InlinedAtLocation(I), AbstractScope(A), |
| 161 | LastInsn(0), FirstInsn(0), DFSIn(0), DFSOut(0), IndentLevel(0) { |
| 162 | if (Parent) |
| 163 | Parent->addChild(this); |
| 164 | } |
| 165 | |
| 166 | virtual ~LexicalScope() {} |
| 167 | |
| 168 | // Accessors. |
| 169 | LexicalScope *getParent() const { return Parent; } |
| 170 | const MDNode *getDesc() const { return Desc; } |
| 171 | const MDNode *getInlinedAt() const { return InlinedAtLocation; } |
| 172 | const MDNode *getScopeNode() const { return Desc; } |
| 173 | bool isAbstractScope() const { return AbstractScope; } |
| 174 | SmallVector<LexicalScope *, 4> &getChildren() { return Children; } |
| 175 | SmallVector<InsnRange, 4> &getRanges() { return Ranges; } |
| 176 | |
| 177 | /// addChild - Add a child scope. |
| 178 | void addChild(LexicalScope *S) { Children.push_back(S); } |
| 179 | |
| 180 | /// openInsnRange - This scope covers instruction range starting from MI. |
| 181 | void openInsnRange(const MachineInstr *MI) { |
| 182 | if (!FirstInsn) |
| 183 | FirstInsn = MI; |
| 184 | |
| 185 | if (Parent) |
| 186 | Parent->openInsnRange(MI); |
| 187 | } |
| 188 | |
| 189 | /// extendInsnRange - Extend the current instruction range covered by |
| 190 | /// this scope. |
| 191 | void extendInsnRange(const MachineInstr *MI) { |
| 192 | assert (FirstInsn && "MI Range is not open!"); |
| 193 | LastInsn = MI; |
| 194 | if (Parent) |
| 195 | Parent->extendInsnRange(MI); |
| 196 | } |
| 197 | |
| 198 | /// closeInsnRange - Create a range based on FirstInsn and LastInsn collected |
| 199 | /// until now. This is used when a new scope is encountered while walking |
| 200 | /// machine instructions. |
| 201 | void closeInsnRange(LexicalScope *NewScope = NULL) { |
| 202 | assert (LastInsn && "Last insn missing!"); |
| 203 | Ranges.push_back(InsnRange(FirstInsn, LastInsn)); |
| 204 | FirstInsn = NULL; |
| 205 | LastInsn = NULL; |
| 206 | // If Parent dominates NewScope then do not close Parent's instruction |
| 207 | // range. |
| 208 | if (Parent && (!NewScope || !Parent->dominates(NewScope))) |
| 209 | Parent->closeInsnRange(NewScope); |
| 210 | } |
| 211 | |
| 212 | /// dominates - Return true if current scope dominsates given lexical scope. |
Devang Patel | 92a36e6 | 2011-08-12 18:18:02 +0000 | [diff] [blame] | 213 | bool dominates(const LexicalScope *S) const { |
Devang Patel | 103b8e6 | 2011-08-10 19:04:06 +0000 | [diff] [blame] | 214 | if (S == this) |
| 215 | return true; |
| 216 | if (DFSIn < S->getDFSIn() && DFSOut > S->getDFSOut()) |
| 217 | return true; |
| 218 | return false; |
| 219 | } |
| 220 | |
| 221 | // Depth First Search support to walk and manipulate LexicalScope hierarchy. |
| 222 | unsigned getDFSOut() const { return DFSOut; } |
| 223 | void setDFSOut(unsigned O) { DFSOut = O; } |
| 224 | unsigned getDFSIn() const { return DFSIn; } |
| 225 | void setDFSIn(unsigned I) { DFSIn = I; } |
| 226 | |
| 227 | /// dump - print lexical scope. |
| 228 | void dump() const; |
| 229 | |
| 230 | private: |
| 231 | LexicalScope *Parent; // Parent to this scope. |
| 232 | AssertingVH<const MDNode> Desc; // Debug info descriptor. |
| 233 | AssertingVH<const MDNode> InlinedAtLocation; // Location at which this |
| 234 | // scope is inlined. |
| 235 | bool AbstractScope; // Abstract Scope |
| 236 | SmallVector<LexicalScope *, 4> Children; // Scopes defined in scope. |
| 237 | // Contents not owned. |
| 238 | SmallVector<InsnRange, 4> Ranges; |
| 239 | |
| 240 | const MachineInstr *LastInsn; // Last instruction of this scope. |
| 241 | const MachineInstr *FirstInsn; // First instruction of this scope. |
| 242 | unsigned DFSIn, DFSOut; // In & Out Depth use to determine |
| 243 | // scope nesting. |
| 244 | mutable unsigned IndentLevel; // Private state for dump() |
| 245 | }; |
| 246 | |
| 247 | } // end llvm namespace |
| 248 | |
| 249 | #endif |