[turbofan] First version of loop peeling.

src/compiler/common-operator.cc

Index: src/compiler/common-operator.cc
diff --git a/src/compiler/common-operator.cc b/src/compiler/common-operator.cc
index 54059ac29a6f09bf11f098d528315ec1f7815776..09f9a5a90d0babd92e26c5b91f9d77ed3eb5b455 100644
--- a/src/compiler/common-operator.cc
+++ b/src/compiler/common-operator.cc
@@ -486,6 +486,23 @@ const Operator* CommonOperatorBuilder::Projection(size_t index) {
       index);                                  // parameter
 }
 
+
+const Operator* CommonOperatorBuilder::ResizeMergeOrPhi(const Operator* op,
+                                                        int size) {
+  if (op->opcode() == IrOpcode::kPhi) {
+    return Phi(OpParameter<MachineType>(op), size);
+  } else if (op->opcode() == IrOpcode::kEffectPhi) {
+    return EffectPhi(size);
+  } else if (op->opcode() == IrOpcode::kMerge) {
+    return Merge(size);
+  } else if (op->opcode() == IrOpcode::kLoop) {
+    return Loop(size);
+  } else {
+    UNREACHABLE();
+    return nullptr;
+  }
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8