[PATCH] [X86] replace (atomic fetch_add of 0) by (mfence; mov)

[David Majnemer]

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Comment at: lib/Target/X86/X86ISelDAGToDAG.cpp:1810-1811
@@ +1809,4 @@
+  // We must copy the information about the memory operand, but change the flags
+  // to remove
+  // the mayStore flag.
+  MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
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This should be on the previous line.

http://reviews.llvm.org/D5091