Add new 'Checker' and 'CheckerVisitor' classes, which represent a more powerful

interface to plug in domain-specific checker logic than the current
GRSimpleAPICheck interface. The new 'Checker' interface can actually generate
new nodes, allowing it to modify the state and refine the analysis (which
GRSimpleAPIChecks could not).

llvm-svn: 76793

clang/include/clang/Analysis/PathSensitive/Checker.h

@@ -0,0 +1,102 @@
+//== Checker.h - Abstract interface for checkers -----------------*- C++ -*--=//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines Checker and CheckerVisitor, classes used for creating
+//  domain-specific checks.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYSIS_CHECKER
+#define LLVM_CLANG_ANALYSIS_CHECKER
+#include "clang/Analysis/Support/SaveAndRestore.h"
+#include "clang/Analysis/PathSensitive/GRCoreEngine.h"
+#include "clang/Analysis/PathSensitive/GRState.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/ExprObjC.h"
+#include "clang/AST/StmtCXX.h"
+#include "clang/AST/StmtObjC.h"
+
+//===----------------------------------------------------------------------===//
+// Checker interface.
+//===----------------------------------------------------------------------===//
+
+namespace clang {
+  class GRExprEngine;
+
+class CheckerContext {
+  ExplodedNodeSet<GRState> &Dst;
+  GRStmtNodeBuilder<GRState> &B;
+  GRExprEngine &Eng;
+  ExplodedNode<GRState> *Pred;
+  SaveAndRestore<bool> OldSink;
+  SaveAndRestore<const void*> OldTag;
+  SaveAndRestore<ProgramPoint::Kind> OldPointKind;
+  SaveOr OldHasGen;
+
+public:
+  CheckerContext(ExplodedNodeSet<GRState> &dst,
+                 GRStmtNodeBuilder<GRState> &builder,
+                 GRExprEngine &eng,
+                 ExplodedNode<GRState> *pred,
+                 const void *tag, bool preVisit)
+    : Dst(dst), B(builder), Eng(eng), Pred(pred), 
+      OldSink(B.BuildSinks), OldTag(B.Tag),
+      OldPointKind(B.PointKind), OldHasGen(B.HasGeneratedNode) {
+        assert(Dst.empty());
+        B.Tag = tag;
+        if (preVisit)
+          B.PointKind = ProgramPoint::PreStmtKind;        
+      }
+  
+  ~CheckerContext() {
+    if (!B.BuildSinks && Dst.empty() && !B.HasGeneratedNode)
+      Dst.Add(Pred);
+  }
+  
+  ConstraintManager &getConstraintManager() {
+      return Eng.getConstraintManager();
+  }
+  ExplodedNodeSet<GRState> &getNodeSet() { return Dst; }
+  GRStmtNodeBuilder<GRState> &getNodeBuilder() { return B; }
+  ExplodedNode<GRState> *&getPredecessor() { return Pred; }
+  const GRState *getState() { return B.GetState(Pred); }
+  
+  ExplodedNode<GRState> *generateNode(const Stmt* S,
+                                      const GRState *state) {
+    return B.generateNode(S, state, Pred);
+  }
+  
+  void EmitReport(BugReport *R) {
+    Eng.getBugReporter().EmitReport(R);
+  }
+};
+  
+class Checker {
+private:
+  friend class GRExprEngine;
+
+  void GR_Visit(ExplodedNodeSet<GRState> &Dst,
+                GRStmtNodeBuilder<GRState> &Builder,
+                GRExprEngine &Eng,
+                const Stmt *stmt,
+                  ExplodedNode<GRState> *Pred, bool isPrevisit) {
+    CheckerContext C(Dst, Builder, Eng, Pred, getTag(), isPrevisit);    
+    assert(isPrevisit && "Only previsit supported for now.");
+    _PreVisit(C, stmt);
+  }
+  
+public:
+  virtual void _PreVisit(CheckerContext &C, const Stmt *stmt) = 0;
+  virtual const void *getTag() = 0;
+};
+
+} // end clang namespace
+
+#endif
+  

clang/include/clang/Analysis/PathSensitive/CheckerVisitor.def

@@ -0,0 +1,17 @@
+//===-- CheckerVisitor.def - Metadata for CheckerVisitor ----------------*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the AST nodes accepted by the CheckerVisitor class.
+//
+//===---------------------------------------------------------------------===//
+
+PREVISIT(CallExpr)
+PREVISIT(ObjCMessageExpr)
+
+#undef PREVISIT

clang/include/clang/Analysis/PathSensitive/CheckerVisitor.h

@@ -0,0 +1,54 @@
+//== CheckerVisitor.h - Abstract visitor for checkers ------------*- C++ -*--=//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines CheckerVisitor.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYSIS_CHECKERVISITOR
+#define LLVM_CLANG_ANALYSIS_CHECKERVISITOR
+#include "clang/Analysis/PathSensitive/Checker.h"
+  
+namespace clang {
+
+//===----------------------------------------------------------------------===//
+// Checker visitor interface.  Used by subclasses of Checker to specify their
+// own checker visitor logic.
+//===----------------------------------------------------------------------===//
+  
+/// CheckerVisitor - This class implements a simple visitor for Stmt subclasses.
+/// Since Expr derives from Stmt, this also includes support for visiting Exprs.
+template<typename ImplClass>
+class CheckerVisitor : public Checker {
+public:
+  virtual void _PreVisit(CheckerContext &C, const Stmt *stmt) {
+    PreVisit(C, stmt);
+  }
+
+  void PreVisit(CheckerContext &C, const Stmt *S) {
+    switch (S->getStmtClass()) {
+      default:
+        assert(false && "Unsupport statement.");
+        return;
+#define PREVISIT(NAME) \
+case Stmt::NAME ## Class:\
+static_cast<ImplClass*>(this)->PreVisit ## NAME(C, static_cast<const NAME*>(S));
+#include "clang/Analysis/PathSensitive/CheckerVisitor.def"
+    }
+  }
+  
+#define PREVISIT(NAME) \
+void PreVisit ## NAME(CheckerContext &C, const NAME* S) {}
+#include "clang/Analysis/PathSensitive/CheckerVisitor.def"
+};
+  
+} // end clang namespace
+
+#endif
+