From: Ted Kremenek <kremenek@apple.com>
Date: Wed, 23 Apr 2008 05:03:18 +0000 (+0000)
Subject: Remove false path where the default branch in a switch statement would
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5014ab113eb211b8320ae30b173d7020352663c6;p=clang

Remove false path where the default branch in a switch statement would
always be taken even if it was not feasible.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@50132 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/GRExprEngine.cpp b/lib/Analysis/GRExprEngine.cpp
index d5b2ce8b35..6072094d05 100644
--- a/lib/Analysis/GRExprEngine.cpp
+++ b/lib/Analysis/GRExprEngine.cpp
@@ -562,6 +562,7 @@ void GRExprEngine::ProcessSwitch(SwitchNodeBuilder& builder) {
 
   APSInt V1(bits, false);
   APSInt V2 = V1;
+  bool DefaultFeasible = false;
   
   for (iterator I = builder.begin(), EI = builder.end(); I != EI; ++I) {
 
@@ -617,8 +618,10 @@ void GRExprEngine::ProcessSwitch(SwitchNodeBuilder& builder) {
       isFeasible = false;
       StNew = Assume(DefaultSt, Res, false, isFeasible);
       
-      if (isFeasible)
+      if (isFeasible) {
+        DefaultFeasible = true;
         DefaultSt = StNew;
+      }
 
       // Concretize the next value in the range.
       if (V1 == V2)
@@ -632,7 +635,7 @@ void GRExprEngine::ProcessSwitch(SwitchNodeBuilder& builder) {
   
   // If we reach here, than we know that the default branch is
   // possible.  
-  builder.generateDefaultCaseNode(DefaultSt);
+  if (DefaultFeasible) builder.generateDefaultCaseNode(DefaultSt);
 }
 
 //===----------------------------------------------------------------------===//