Handle Expr-nospecialize

Author: mlechu

src/ast.jl

@@ -498,17 +498,20 @@ end
 # the middle of a pass.
 const CompileHints = Base.ImmutableDict{Symbol,Any}
 
-function setmeta(ex::SyntaxTree; kws...)
+function setmeta!(ex::SyntaxTree; kws...)
     @assert length(kws) == 1 # todo relax later ?
     key = first(keys(kws))
     value = first(values(kws))
     meta = begin
         m = get(ex, :meta, nothing)
         isnothing(m) ? CompileHints(key, value) : CompileHints(m, key, value)
     end
-    setattr(ex; meta=meta)
+    setattr!(ex; meta=meta)
+    ex
 end
 
+setmeta(ex::SyntaxTree; kws...) = setmeta!(copy_node(ex); kws...)
+
 function getmeta(ex::SyntaxTree, name::Symbol, default)
     meta = get(ex, :meta, nothing)
     isnothing(meta) ? default : get(meta, name, default)

src/compat.jl

@@ -191,7 +191,7 @@ function _insert_convert_expr(@nospecialize(e), graph::SyntaxGraph, src::SourceA
     maybe_kind = find_kind(string(e.head))
     st_k = isnothing(maybe_kind) ? K"None" : maybe_kind
     st_flags = 0x0000
-    child_exprs = copy(e.args)
+    child_exprs::Vector{Any} = copy(e.args)
 
     # The following are special cases where the kind, flags, or children are
     # different from what we guessed above.
@@ -247,9 +247,21 @@ function _insert_convert_expr(@nospecialize(e), graph::SyntaxGraph, src::SourceA
         # Existing behaviour appears to just ignore any extra args
         return _insert_convert_expr(e.args[1], graph, src)
     elseif e.head === :meta
-        @assert nargs <= 2
         @assert e.args[1] isa Symbol
-        child_exprs[1] = Expr(:sym_not_identifier, e.args[1])
+        if e.args[1] === :nospecialize
+            if nargs > 2
+                st_k = K"block"
+                # Kick the can down the road
+                child_exprs = map(c->Expr(:meta, :nospecialize, c), child_exprs[2:end])
+            else
+                st_id, src = _insert_convert_expr(e.args[2], graph, src)
+                setmeta!(SyntaxTree(graph, st_id); nospecialize=true)
+                return st_id, src
+            end
+        else
+            @assert nargs === 1
+            child_exprs[1] = Expr(:sym_not_identifier, e.args[1])
+        end
     elseif e.head === Symbol("'")
         @assert nargs === 1
         st_k = K"call"
@@ -394,14 +406,19 @@ function _insert_convert_expr(@nospecialize(e), graph::SyntaxGraph, src::SourceA
 
     st_flags |= JS.NON_TERMINAL_FLAG
     st_id = _insert_tree_node(graph, st_k, src, st_flags)
+    st_child_ids, last_src = _insert_expr_children(child_exprs, graph, src)
+    setchildren!(graph, st_id, st_child_ids)
+    return st_id, last_src
+end
+
+function _insert_expr_children(child_exprs::Vector{Any}, graph::SyntaxGraph,
+                               src::SourceAttrType)
     st_child_ids = NodeId[]
     last_src = src
     for c in child_exprs
         (c_id, c_src) = _insert_convert_expr(c, graph, last_src)
         isnothing(c_id) || push!(st_child_ids, c_id)
         last_src = something(c_src, src)
     end
-
-    setchildren!(graph, st_id, st_child_ids)
-    return (st_id, last_src)
+    return st_child_ids, last_src
 end

src/syntax_graph.jl

@@ -246,13 +246,17 @@ function attrnames(ex::SyntaxTree)
     [name for (name, value) in pairs(attrs) if haskey(value, ex._id)]
 end
 
-function setattr(ex::SyntaxTree; extra_attrs...)
+function copy_node(ex::SyntaxTree)
     graph = syntax_graph(ex)
     id = newnode!(graph)
     if !is_leaf(ex)
         setchildren!(graph, id, _node_ids(graph, children(ex)...))
     end
-    ex2 = SyntaxTree(graph, id)
+    SyntaxTree(graph, id)
+end
+
+function setattr(ex::SyntaxTree; extra_attrs...)
+    ex2 = copy_node(ex)
     copy_attrs!(ex2, ex, true)
     setattr!(ex2; extra_attrs...)
     ex2