Subzero: Fold icmp into br/select lowering.

src/IceCfgNode.cpp

Index: src/IceCfgNode.cpp
diff --git a/src/IceCfgNode.cpp b/src/IceCfgNode.cpp
index a9b34fc6cd029b4dab305cf84b64b83537c3642a..fb2ab396c25b04507549c76b73a899e473558818 100644
--- a/src/IceCfgNode.cpp
+++ b/src/IceCfgNode.cpp
@@ -516,6 +516,7 @@ void CfgNode::genCode() {
   LoweringContext &Context = Target->getContext();
   // Lower the regular instructions.
   Context.init(this);
+  Target->initNodeForLowering(this);
   while (!Context.atEnd()) {
     InstList::iterator Orig = Context.getCur();
     if (llvm::isa<InstRet>(*Orig))