From 3f916501c91d3f6f37b1d43276c440343f9454f6 Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Mon, 10 Mar 2008 15:17:11 +0000
Subject: [PATCH] Add transfer function support for pointer arithmetic where
 the increment/decrement operand is on the left side.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@48144 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Analysis/PathSensitive/GRExprEngine.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/clang/Analysis/PathSensitive/GRExprEngine.h b/include/clang/Analysis/PathSensitive/GRExprEngine.h
index 4cf9f2042f..ad592b7477 100644
--- a/include/clang/Analysis/PathSensitive/GRExprEngine.h
+++ b/include/clang/Analysis/PathSensitive/GRExprEngine.h
@@ -428,7 +428,17 @@ protected:
         return TF->EvalBinOp(BasicVals, Op, cast<LVal>(L), cast<NonLVal>(R));
     }
     
-    return TF->EvalBinOp(BasicVals, Op, cast<NonLVal>(L), cast<NonLVal>(R));
+    if (isa<LVal>(R)) {
+      // Support pointer arithmetic where the increment/decrement operand
+      // is on the left and the pointer on the right.
+      
+      assert (Op == BinaryOperator::Add || Op == BinaryOperator::Sub);
+
+      // Commute the operands.      
+      return TF->EvalBinOp(BasicVals, Op, cast<LVal>(R), cast<NonLVal>(L));
+    }
+    else
+      return TF->EvalBinOp(BasicVals, Op, cast<NonLVal>(L), cast<NonLVal>(R));
   }
   
   void EvalCall(NodeSet& Dst, CallExpr* CE, LVal L, NodeTy* Pred) {
-- 
2.40.0