From 448538d86054fb732d6ca873093334b7881dc4d8 Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Tue, 26 Feb 2008 23:04:29 +0000
Subject: [PATCH] Added boilerplate for plug-in transfer function support for
 CallExprs. GRSimpleVals performs the following action: invalidate all values
 passed-by-reference.

llvm-svn: 47638
---
 clang/Analysis/GRSimpleVals.cpp               | 25 +++++++++++++++++++
 clang/Analysis/GRSimpleVals.h                 |  7 ++++++
 .../Analysis/PathSensitive/GRExprEngine.h     |  2 +-
 .../Analysis/PathSensitive/GRTransferFuncs.h  | 10 ++++++++
 4 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/clang/Analysis/GRSimpleVals.cpp b/clang/Analysis/GRSimpleVals.cpp
index 549aa0bb4ff3..4d9dccf621e0 100644
--- a/clang/Analysis/GRSimpleVals.cpp
+++ b/clang/Analysis/GRSimpleVals.cpp
@@ -14,6 +14,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "GRSimpleVals.h"
+#include "ValueState.h"
 #include "clang/Basic/Diagnostic.h"
 
 using namespace clang;
@@ -329,3 +330,27 @@ RVal GRSimpleVals::EvalNE(ValueManager& ValMgr, LVal L, LVal R) {
   
   return NonLVal::MakeIntTruthVal(ValMgr, true);
 }
+
+//===----------------------------------------------------------------------===//
+// Transfer function for Function Calls.
+//===----------------------------------------------------------------------===//
+
+ValueStateImpl*
+GRSimpleVals::EvalCall(ValueStateManager& StateMgr, ValueManager& ValMgr,
+                           CallExpr* CE, LVal L, ValueStateImpl* StImpl) {
+  
+  ValueState St(StImpl);
+  
+  // Invalidate all arguments passed in by reference (LVals).
+
+  for (CallExpr::arg_iterator I = CE->arg_begin(), E = CE->arg_end();
+        I != E; ++I) {
+
+    RVal V = StateMgr.GetRVal(St, *I);
+    
+    if (isa<LVal>(V))
+      St = StateMgr.SetRVal(St, cast<LVal>(V), UnknownVal());
+  }
+  
+  return St.getImpl();
+}
diff --git a/clang/Analysis/GRSimpleVals.h b/clang/Analysis/GRSimpleVals.h
index 870166e8f4b7..10d4acd4b9f2 100644
--- a/clang/Analysis/GRSimpleVals.h
+++ b/clang/Analysis/GRSimpleVals.h
@@ -50,6 +50,13 @@ public:
   virtual RVal EvalBinOp(ValueManager& ValMgr, BinaryOperator::Opcode Op,
                          LVal L, NonLVal R);  
   
+  // Calls.
+  
+  virtual ValueStateImpl* EvalCall(ValueStateManager& StateMgr,
+                                   ValueManager& ValMgr,
+                                   CallExpr* CE, LVal L,
+                                   ValueStateImpl* StImpl);
+  
 protected:
   
   // Equality operators for LVals.
diff --git a/clang/include/clang/Analysis/PathSensitive/GRExprEngine.h b/clang/include/clang/Analysis/PathSensitive/GRExprEngine.h
index a5f88354b8f8..5c9092943bbd 100644
--- a/clang/include/clang/Analysis/PathSensitive/GRExprEngine.h
+++ b/clang/include/clang/Analysis/PathSensitive/GRExprEngine.h
@@ -410,7 +410,7 @@ protected:
   }
   
   StateTy EvalCall(CallExpr* CE, LVal L, StateTy St) {
-    return St;     
+    return StateTy(TF->EvalCall(StateMgr, ValMgr, CE, L, St.getImpl()));
   }
   
   StateTy MarkBranch(StateTy St, Stmt* Terminator, bool branchTaken);
diff --git a/clang/include/clang/Analysis/PathSensitive/GRTransferFuncs.h b/clang/include/clang/Analysis/PathSensitive/GRTransferFuncs.h
index 2a8ec2b6f77c..b4953d6401de 100644
--- a/clang/include/clang/Analysis/PathSensitive/GRTransferFuncs.h
+++ b/clang/include/clang/Analysis/PathSensitive/GRTransferFuncs.h
@@ -19,6 +19,9 @@
 
 namespace clang {
   
+  class ValueStateImpl;
+  class ValueStateManager;
+  
 class GRTransferFuncs {
 public:
   GRTransferFuncs() {}
@@ -47,6 +50,13 @@ public:
   
   virtual RVal EvalBinOp(ValueManager& ValMgr, BinaryOperator::Opcode Op,
                          LVal L, NonLVal R) = 0;
+  
+  // Calls.
+  
+  virtual ValueStateImpl* EvalCall(ValueStateManager& StateMgr,
+                                   ValueManager& ValMgr,
+                                   CallExpr* CE, LVal L,
+                                   ValueStateImpl* StImpl) = 0;
 };
   
 } // end clang namespace