[llvm-commits] [llvm] r138243 - /llvm/trunk/lib/Transforms/Scalar/ObjCARC.cpp

[Dan Gohman]

Author: djg
Date: Mon Aug 22 12:29:37 2011
New Revision: 138243

URL: http://llvm.org/viewvc/llvm-project?rev=138243&view=rev
Log:
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Modified:
    llvm/trunk/lib/Transforms/Scalar/ObjCARC.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/ObjCARC.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/ObjCARC.cpp?rev=138243&r1=138242&r2=138243&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/ObjCARC.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/ObjCARC.cpp Mon Aug 22 12:29:37 2011
@@ -344,6 +344,10 @@
       break;
     default:
       // For anything else, check all the operands.
+      // Note that this includes both operands of a Store: while the first
+      // operand isn't actually being dereferenced, it is being stored to
+      // memory where we can no longer track who might read it and dereference
+      // it, so we have to consider it potentially used.
       for (User::const_op_iterator OI = I->op_begin(), OE = I->op_end();
            OI != OE; ++OI)
         if (IsPotentialUse(*OI))