r201829 - [analyzer] Fix a bug in IdenticalExprChecker concerning while loops.

[Jordan Rose]

Author: jrose
Date: Thu Feb 20 18:18:31 2014
New Revision: 201829

URL: http://llvm.org/viewvc/llvm-project?rev=201829&view=rev
Log:
[analyzer] Fix a bug in IdenticalExprChecker concerning while loops.

Somehow both Daniel and I missed the fact that while loops are only identical
if they have identical bodies.

Patch by Daniel Fahlgren!

Modified:
    cfe/trunk/lib/StaticAnalyzer/Checkers/IdenticalExprChecker.cpp
    cfe/trunk/test/Analysis/identical-expressions.cpp

Modified: cfe/trunk/lib/StaticAnalyzer/Checkers/IdenticalExprChecker.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Checkers/IdenticalExprChecker.cpp?rev=201829&r1=201828&r2=201829&view=diff
==============================================================================
--- cfe/trunk/lib/StaticAnalyzer/Checkers/IdenticalExprChecker.cpp (original)
+++ cfe/trunk/lib/StaticAnalyzer/Checkers/IdenticalExprChecker.cpp Thu Feb 20 18:18:31 2014
@@ -361,8 +361,13 @@ static bool isIdenticalStmt(const ASTCon
     const WhileStmt *WStmt1 = cast<WhileStmt>(Stmt1);
     const WhileStmt *WStmt2 = cast<WhileStmt>(Stmt2);
 
-    return isIdenticalStmt(Ctx, WStmt1->getCond(), WStmt2->getCond(),
-                           IgnoreSideEffects);
+    if (!isIdenticalStmt(Ctx, WStmt1->getCond(), WStmt2->getCond(),
+                         IgnoreSideEffects))
+      return false;
+    if (!isIdenticalStmt(Ctx, WStmt1->getBody(), WStmt2->getBody(),
+                         IgnoreSideEffects))
+      return false;
+    return true;
   }
   case Stmt::IfStmtClass: {
     const IfStmt *IStmt1 = cast<IfStmt>(Stmt1);

Modified: cfe/trunk/test/Analysis/identical-expressions.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/identical-expressions.cpp?rev=201829&r1=201828&r2=201829&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/identical-expressions.cpp (original)
+++ cfe/trunk/test/Analysis/identical-expressions.cpp Thu Feb 20 18:18:31 2014
@@ -1287,6 +1287,17 @@ void test_identical_branches_while(bool
   }
 }
 
+void test_identical_branches_while_2(bool b) {
+  int i = 10;
+  if (b) { // no-warning
+    while (func())
+      i--;
+  } else {
+    while (func())
+      i++;
+  }
+}
+
 void test_identical_branches_do_while(bool b) {
   int i = 10;
   if (b) { // expected-warning {{true and false branches are identical}}