Fix bugs in simplified lowering relating to int32/uint32 signs.

src/compiler/basic-block-instrumentor.cc

Index: src/compiler/basic-block-instrumentor.cc
diff --git a/src/compiler/basic-block-instrumentor.cc b/src/compiler/basic-block-instrumentor.cc
index 708ec497d4f9d8445a7abd1fc15b63cb981b16db..59bb7f415853ecc5e993e2287692c2ca1ebc9764 100644
--- a/src/compiler/basic-block-instrumentor.cc
+++ b/src/compiler/basic-block-instrumentor.cc
@@ -69,7 +69,7 @@ BasicBlockProfiler::Data* BasicBlockInstrumentor::Instrument(
   CommonOperatorBuilder common(graph->zone());
   Node* zero = graph->NewNode(common.Int32Constant(0));
   Node* one = graph->NewNode(common.Int32Constant(1));
-  MachineOperatorBuilder machine;
+  MachineOperatorBuilder machine(graph->zone());
   BasicBlockVector* blocks = schedule->rpo_order();
   size_t block_number = 0;
   for (BasicBlockVector::iterator it = blocks->begin(); block_number < n_blocks;