simplify targetstore creation

Author: aviatesk

src/codeedges.jl

@@ -255,10 +255,7 @@ function direct_links!(cl::CodeLinks, src::CodeInfo)
                     cl.nameassigns[name] = assign = Int[]
                 end
                 push!(assign, i)
-                targetstore = get(cl.namepreds, name, nothing)
-                if targetstore === nothing
-                    cl.namepreds[name] = targetstore = Links()
-                end
+                targetstore = get!(Links, cl.namepreds, name)
                 target = P(name, targetstore)
                 add_links!(target, stmt, cl)
             elseif name in (nothing, false)
@@ -281,10 +278,7 @@ function direct_links!(cl::CodeLinks, src::CodeInfo)
                 if isa(lhs, Symbol)
                     lhs = GlobalRef(cl.thismod, lhs)
                 end
-                targetstore = get(cl.namepreds, lhs, nothing)
-                if targetstore === nothing
-                    cl.namepreds[lhs] = targetstore = Links()
-                end
+                targetstore = get!(Links, cl.namepreds, lhs)
                 target = P(lhs, targetstore)
                 assign = get(cl.nameassigns, lhs, nothing)
                 if assign === nothing