[cfe-commits] r53906 - in /cfe/trunk/lib/Analysis: CheckDeadStores.cpp DeadStores.cpp

[Ted Kremenek]

Author: kremenek
Date: Tue Jul 22 09:41:47 2008
New Revision: 53906

URL: http://llvm.org/viewvc/llvm-project?rev=53906&view=rev
Log:
Rename file.

Added:
    cfe/trunk/lib/Analysis/CheckDeadStores.cpp
      - copied unchanged from r53905, cfe/trunk/lib/Analysis/DeadStores.cpp
Removed:
    cfe/trunk/lib/Analysis/DeadStores.cpp

Removed: cfe/trunk/lib/Analysis/DeadStores.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/DeadStores.cpp?rev=53905&view=auto

==============================================================================
--- cfe/trunk/lib/Analysis/DeadStores.cpp (original)
+++ cfe/trunk/lib/Analysis/DeadStores.cpp (removed)
@@ -1,152 +0,0 @@
-//==- DeadStores.cpp - Check for stores to dead variables --------*- 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 a DeadStores, a flow-sensitive checker that looks for
-//  stores to variables that are no longer live.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/Analysis/LocalCheckers.h"
-#include "clang/Analysis/Analyses/LiveVariables.h"
-#include "clang/Analysis/Visitors/CFGRecStmtVisitor.h"
-#include "clang/Analysis/PathSensitive/BugReporter.h"
-#include "clang/Analysis/PathSensitive/GRExprEngine.h"
-#include "clang/Basic/Diagnostic.h"
-#include "clang/AST/ASTContext.h"
-#include "clang/AST/ParentMap.h"
-#include "llvm/Support/Compiler.h"
-
-using namespace clang;
-
-namespace {
-
-class VISIBILITY_HIDDEN DeadStoreObs : public LiveVariables::ObserverTy {
-  ASTContext &Ctx;
-  BugReporter& BR;
-  ParentMap& Parents;
-    
-public:
-  DeadStoreObs(ASTContext &ctx, BugReporter& br, ParentMap& parents)
-    : Ctx(ctx), BR(br), Parents(parents) {}
-  
-  virtual ~DeadStoreObs() {}
-  
-  void Report(VarDecl* V, bool inEnclosing, SourceLocation L, SourceRange R,
-              bool isInitialization = false) {
-
-    std::string name(V->getName());
-    
-    if (isInitialization) {
-      std::string msg = "Value stored to '" + name +
-        "' during its initialization is never read";
-      
-      BR.EmitBasicReport("dead initialization", msg.c_str(), L, R);      
-    }
-    else {
-      std::string msg = inEnclosing
-        ? "Although the value stored to '" + name +
-          "' is used in the enclosing expression, the value is never actually"
-          " read from '" + name + "'"
-        : "Value stored to '" + name + "' is never read";
-    
-      BR.EmitBasicReport("dead store", msg.c_str(), L, R);
-    }
-  }
-  
-  void CheckVarDecl(VarDecl* VD, Expr* Ex, Expr* Val,
-                    bool hasEnclosing,
-                    const LiveVariables::AnalysisDataTy& AD,
-                    const LiveVariables::ValTy& Live) {
-
-    if (VD->hasLocalStorage() && !Live(VD, AD))
-      Report(VD, hasEnclosing, Ex->getSourceRange().getBegin(),
-             Val->getSourceRange());      
-  }
-  
-  void CheckDeclRef(DeclRefExpr* DR, Expr* Val,
-                    const LiveVariables::AnalysisDataTy& AD,
-                    const LiveVariables::ValTy& Live) {
-    
-    if (VarDecl* VD = dyn_cast<VarDecl>(DR->getDecl()))
-      CheckVarDecl(VD, DR, Val, false, AD, Live);
-  }
-  
-  virtual void ObserveStmt(Stmt* S,
-                           const LiveVariables::AnalysisDataTy& AD,
-                           const LiveVariables::ValTy& Live) {
-    
-    // Skip statements in macros.
-    if (S->getLocStart().isMacroID())
-      return;
-    
-    if (BinaryOperator* B = dyn_cast<BinaryOperator>(S)) {    
-      if (!B->isAssignmentOp()) return; // Skip non-assignments.
-      
-      if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(B->getLHS()))
-        if (VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) {
-     
-          // Special case: check for assigning null to a pointer.  This
-          //  is a common form of defensive programming.
-          // FIXME: Make this optional?
-          
-          Expr* Val = B->getRHS();
-          llvm::APSInt Result(Ctx.getTypeSize(Val->getType()));
-          
-          if (VD->getType()->isPointerType() &&
-              Val->IgnoreParenCasts()->isIntegerConstantExpr(Result, Ctx, 0))
-            if (Result == 0)
-              return;
-
-          CheckVarDecl(VD, DR, Val, Parents.isSubExpr(B), AD, Live);
-        }              
-    }
-    else if (UnaryOperator* U = dyn_cast<UnaryOperator>(S)) {
-      if (!U->isIncrementOp())
-        return;
-      
-      Expr *Ex = U->getSubExpr()->IgnoreParenCasts();
-      
-      if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(Ex))
-        CheckDeclRef(DR, U, AD, Live);
-    }    
-    else if (DeclStmt* DS = dyn_cast<DeclStmt>(S))
-      // Iterate through the decls.  Warn if any initializers are complex
-      // expressions that are not live (never used).
-      for (ScopedDecl* SD = DS->getDecl(); SD; SD = SD->getNextDeclarator()) {        
-        
-        VarDecl* V = dyn_cast<VarDecl>(SD);
-        if (!V) continue;
-        
-        if (V->hasLocalStorage())
-          if (Expr* E = V->getInit())
-            if (!Live(V, AD)) {
-              // Special case: check for initializations with constants.
-              //
-              //  e.g. : int x = 0;
-              //
-              // If x is EVER assigned a new value later, don't issue
-              // a warning.  This is because such initialization can be
-              // due to defensive programming.
-              if (!E->isConstantExpr(Ctx,NULL))
-                Report(V, false, V->getLocation(), E->getSourceRange(), true);
-            }
-      }
-  }
-};
-  
-} // end anonymous namespace
-
-//===----------------------------------------------------------------------===//
-// Driver function to invoke the Dead-Stores checker on a CFG.
-//===----------------------------------------------------------------------===//
-
-void clang::CheckDeadStores(LiveVariables& L, BugReporter& BR) {  
-  DeadStoreObs A(BR.getContext(), BR, BR.getParentMap());
-  L.runOnAllBlocks(*BR.getCFG(), &A);
-}