Removed "ObserverTy" from core DataflowValues types. The observer

mechanism can be implemented simply by affixing the Observer to an
analysis meta data, so it doesn't need to be a required type.  This
also permits analyses not to implement an Observer if it doesn't make
sense.

Changed "DataflowValues::MetaDataTy" to
"DataflowValues::AnalysisDataTy" to reflect that the type
enscapsulated the data associated with analyzing a given CFG.

Changed CFGStmtVisitor::BlockStmt_VisitImplicitControlFlowStmt(Stmt*)
to ...VisitImplicitControlFlowExpr(Expr*).  The type narrowing is more
precise and more useful to clients.

Added CFGStmtVisitor::BlockStmt_VisitExpr to reflect the visitation of
expressions at the block statement level.  This captures all implicit
control-flow statements as well as other expressions that are hoisted
to the block level (such as conditions for terminators and function
calls).  This is especially useful for dataflow analysis.

llvm-svn: 42034

clang/Analysis/DataflowSolver.h

@@ -62,14 +62,13 @@ public:
   typedef typename _DFValuesTy::AnalysisDirTag   AnalysisDirTag;
   typedef typename _DFValuesTy::ValTy            ValTy;
   typedef typename _DFValuesTy::BlockDataMapTy   BlockDataMapTy;
-  typedef typename _DFValuesTy::ObserverTy       ObserverTy;
 
   //===--------------------------------------------------------------------===//
   // External interface: constructing and running the solver.
   //===--------------------------------------------------------------------===//
   
 public:
-  DataflowSolver(DFValuesTy& d, ObserverTy* o = NULL) : D(d), O(o) {}
+  DataflowSolver(DFValuesTy& d) : D(d) {}
   ~DataflowSolver() {}  
   
   /// runOnCFG - Computes dataflow values for all blocks in a CFG.
@@ -86,7 +85,7 @@ public:
   ///  only be used for querying the dataflow values within a block with
   ///  and Observer object.
   void runOnBlock(const CFGBlock* B) {
-    TransferFuncsTy TF (D.getMetaData(),O);
+    TransferFuncsTy TF (D.getAnalysisData());
     ProcessBlock(B,TF,AnalysisDirTag());
   }
   
@@ -106,7 +105,7 @@ private:
     WorkList.enqueue(&cfg.getEntry());
     
     // Create the state for transfer functions.
-    TransferFuncsTy TF(D.getMetaData(),O);
+    TransferFuncsTy TF(D.getAnalysisData());
     
     // Process the worklist until it is empty.    
     while (!WorkList.isEmpty()) {
@@ -131,7 +130,7 @@ private:
     WorkList.enqueue(&cfg.getExit());
     
     // Create the state for transfer functions.
-    TransferFuncsTy TF(D.getMetaData(),O);
+    TransferFuncsTy TF(D.getAnalysisData());
     
     // Process the worklist until it is empty.    
     while (!WorkList.isEmpty()) {
@@ -213,7 +212,6 @@ private:
 
 private:
   DFValuesTy& D;
-  ObserverTy* O;
 };  
   
 

clang/Analysis/UnintializedValues.cpp

@@ -24,26 +24,30 @@ using namespace clang;
 
 namespace {
 
-class RegisterDecls : public CFGVarDeclVisitor<RegisterDecls> {
+class RegisterDeclsAndExprs : public CFGVarDeclVisitor<RegisterDeclsAndExprs> {
-  UninitializedValues::MetaDataTy& M;
+  UninitializedValues::AnalysisDataTy& AD;
 public:
-  RegisterDecls(const CFG& cfg, UninitializedValues::MetaDataTy& m) :
+  RegisterDeclsAndExprs(const CFG& cfg, UninitializedValues::AnalysisDataTy& ad)
-    CFGVarDeclVisitor<RegisterDecls>(cfg), M(m) {}
+                        : CFGVarDeclVisitor<RegisterDeclsAndExprs>(cfg), AD(ad)
+  {}
   
   void VisitVarDecl(VarDecl* D) {
-    if (M.Map.find(D) == M.Map.end()) {
+    if (AD.VMap.find(D) == AD.VMap.end())
-      M.Map[D] = M.NumDecls++;
+      AD.VMap[D] = AD.Counter++;
-    }
+  }
-  }  
+  
+  void BlockStmt_VisitExpr(Expr* E) {
+    if (AD.EMap.find(E) == AD.EMap.end())
+      AD.EMap[E] = AD.Counter++;
+  }        
 };
   
 } // end anonymous namespace
 
 void UninitializedValues::InitializeValues(const CFG& cfg) {
-  RegisterDecls R(cfg,this->getMetaData());
+  RegisterDeclsAndExprs R(cfg,this->getAnalysisData());
-  R.VisitAllDecls();
+  R.VisitAllDecls();    
-    
+  getBlockDataMap()[ &cfg.getEntry() ].resize( getAnalysisData().Counter );
-  getBlockDataMap()[ &cfg.getEntry() ].resize( getMetaData().NumDecls );
 }
 
 //===--------------------------------------------------------------------===//
@@ -53,15 +57,17 @@ void UninitializedValues::InitializeValues(const CFG& cfg) {
 namespace {
 class TransferFuncs : public CFGStmtVisitor<TransferFuncs,bool> {
   UninitializedValues::ValTy V;
-  UninitializedValues::MetaDataTy& M;
+  UninitializedValues::AnalysisDataTy& AD;
-  UninitializedValues::ObserverTy* O;
 public:
-  TransferFuncs(UninitializedValues::MetaDataTy& m,
+  TransferFuncs(UninitializedValues::AnalysisDataTy& ad) : AD(ad) {
-                UninitializedValues::ObserverTy* o) : M(m), O(o) {
+    V.resize(AD.Counter);
-    V.resize(M.NumDecls);
   }
   
   UninitializedValues::ValTy& getVal() { return V; }
+  
+//  bool VisitDeclRefExpr(DeclRefExpr* DR);
+//  bool VisitBinaryOperator(BinaryOperator* B);
+//  bool VisitUnaryOperator(UnaryOperator* U);    
 };
 } // end anonymous namespace
 

clang/include/clang/Analysis/CFGStmtVisitor.h

@@ -28,7 +28,8 @@ static_cast<ImplClass*>(this)->BlockStmt_Visit ## CLASS(static_cast<CLASS*>(S));
 
 #define DEFAULT_BLOCKSTMT_VISIT(CLASS) RetTy BlockStmt_Visit ## CLASS(CLASS *S)\
 { return\
-  static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowStmt(S); }  
+  static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowExpr(\
+  cast<Expr>(S)); }
 
 template <typename ImplClass, typename RetTy=void>
 class CFGStmtVisitor : public StmtVisitor<ImplClass,RetTy> {
@@ -54,7 +55,11 @@ public:
       }
       
       default:
-        return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(S);                             
+        if (isa<Expr>(S))
+          return 
+            static_cast<ImplClass*>(this)->BlockStmt_VisitExpr(cast<Expr>(S));
+        else
+          return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(S);                             
     }
   }
 
@@ -62,8 +67,12 @@ public:
   DEFAULT_BLOCKSTMT_VISIT(StmtExpr)
   DEFAULT_BLOCKSTMT_VISIT(ConditionalOperator)
   
-  RetTy BlockStmt_VisitImplicitControlFlowStmt(Stmt* S) {
+  RetTy BlockStmt_VisitImplicitControlFlowExpr(Expr* E) {
-    return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(S);
+    return static_cast<ImplClass*>(this)->BlockStmt_VisitExpr(E);
+  }
+  
+  RetTy BlockStmt_VisitExpr(Expr* E) {
+    return static_cast<ImplClass*>(this)->BlockStmt_VisitStmt(E);
   }
   
   RetTy BlockStmt_VisitStmt(Stmt* S) {
@@ -72,12 +81,12 @@ public:
 
   RetTy BlockStmt_VisitLogicalOp(BinaryOperator* B) {
     return 
-     static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowStmt(B);
+     static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowExpr(B);
   }
   
   RetTy BlockStmt_VisitComma(BinaryOperator* B) {
     return
-     static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowStmt(B);
+     static_cast<ImplClass*>(this)->BlockStmt_VisitImplicitControlFlowExpr(B);
   }
 
   //===--------------------------------------------------------------------===//

clang/include/clang/Analysis/CFGVarDeclVisitor.h

@@ -15,7 +15,7 @@
 #ifndef LLVM_CLANG_ANALYSIS_CFG_VARDECL_VISITOR_H
 #define LLVM_CLANG_ANALYSIS_CFG_VARDECL_VISITOR_H
 
-#include "clang/AST/StmtVisitor.h"
+#include "clang/Analysis/CFGStmtVisitor.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/Stmt.h"
 #include "clang/AST/CFG.h"
@@ -23,7 +23,7 @@
 namespace clang {
 
 template <typename ImplClass>
-class CFGVarDeclVisitor : public StmtVisitor<ImplClass> {
+class CFGVarDeclVisitor : public CFGStmtVisitor<ImplClass> {
   const CFG& cfg;
 public:  
   CFGVarDeclVisitor(const CFG& c) : cfg(c) {}

clang/include/clang/Analysis/DataflowValues.h

@@ -35,7 +35,7 @@ namespace dataflow {
 } // end namespace dataflow
     
 
-template <typename TypeClass,
+template <typename ValueTypes,
           typename _AnalysisDirTag = dataflow::forward_analysis_tag >
 class DataflowValues {
 
@@ -44,10 +44,8 @@ class DataflowValues {
   //===--------------------------------------------------------------------===//    
 
 public:
-  typedef typename TypeClass::ValTy                ValTy;
+  typedef typename ValueTypes::ValTy               ValTy;
-  typedef typename TypeClass::MetaDataTy           MetaDataTy;
+  typedef typename ValueTypes::AnalysisDataTy      AnalysisDataTy;  
-  typedef typename TypeClass::ObserverTy           ObserverTy;
-  
   typedef _AnalysisDirTag                          AnalysisDirTag;  
   typedef llvm::DenseMap<const CFGBlock*, ValTy>   BlockDataMapTy;
 
@@ -101,19 +99,20 @@ public:
   BlockDataMapTy& getBlockDataMap() { return BlockDataMap; }
   const BlockDataMapTy& getBlockDataMap() const { return BlockDataMap; }
 
-  /// getMetaData - Retrieves the meta data associated with a dataflow analysis.
+  /// getAnalysisData - Retrieves the meta data associated with a 
+  ///  dataflow analysis for analyzing a particular CFG.  
   ///  This is typically consumed by transfer function code (via the solver).
   ///  This can also be used by subclasses to interpret the dataflow values.
-  MetaDataTy& getMetaData() { return Meta; }
+  AnalysisDataTy& getAnalysisData() { return AnalysisData; }
-  const MetaDataTy& getMetaData() const { return Meta; }
+  const AnalysisDataTy& getAnalysisData() const { return AnalysisData; }
   
   //===--------------------------------------------------------------------===//
   // Internal data.
   //===--------------------------------------------------------------------===//
   
 protected:
-  BlockDataMapTy                     BlockDataMap;
+  BlockDataMapTy     BlockDataMap;
-  MetaDataTy     Meta;
+  AnalysisDataTy     AnalysisData;
 };          
 
 } // end namespace clang

clang/include/clang/Analysis/UninitializedValues.h

@@ -21,10 +21,12 @@
 namespace clang {
 
   class VarDecl;
+  class Expr;
 
-/// UninitializedValuesTypes - Utility class to wrap type declarations
+/// UninitializedValues_ValueTypes - Utility class to wrap type declarations
-///   used for defining the UninitializedValues class.
+///   for dataflow values and dataflow analysis state for the
-class UninitializedValuesTypes {
+///   Unitialized Values analysis.
+class UninitializedValues_ValueTypes {
 public:
   class ValTy {
     llvm::BitVector BV;
@@ -41,26 +43,21 @@ public:
     void copyValues(ValTy& RHS) { BV = RHS.BV; }    
   };
   
-  struct MetaDataTy {
+  struct AnalysisDataTy {
-    llvm::DenseMap<const VarDecl*, unsigned > Map;
+    llvm::DenseMap<const VarDecl*, unsigned > VMap;
-    unsigned NumDecls;
+    llvm::DenseMap<const Expr*, unsigned > EMap;
+    unsigned Counter;
     
-    MetaDataTy() : NumDecls(0) {}
+    AnalysisDataTy() : Counter(0) {}
-  };
-
-  class ObserverTy {
-    virtual ~ObserverTy();
-    virtual void ObserveStmt(Stmt* S, MetaDataTy& M, ValTy& V) {}
-    virtual void ObserveBlockExit(const CFGBlock* B, MetaDataTy& M, ValTy& V) {}
   };
 };
 
-
 /// UninitializedValues - Objects of this class encapsulate dataflow analysis
 ///  information regarding what variable declarations in a function are
 ///  potentially unintialized.
-class UninitializedValues : public DataflowValues<UninitializedValuesTypes> {
+class UninitializedValues : 
-
+  public DataflowValues<UninitializedValues_ValueTypes> {
+  
   //===--------------------------------------------------------------------===//
   // Public interface.
   //===--------------------------------------------------------------------===//