go/src/cmd/compile/internal/ir/copy.go

// Copy returns a shallow copy of n.
func Copy(n Node) Node { … }

// DeepCopy returns a “deep” copy of n, with its entire structure copied
// (except for shared nodes like ONAME, ONONAME, OLITERAL, and OTYPE).
// If pos.IsKnown(), it sets the source position of newly allocated Nodes to pos.
func DeepCopy(pos src.XPos, n Node) Node { … }

// DeepCopyList returns a list of deep copies (using DeepCopy) of the nodes in list.
func DeepCopyList(pos src.XPos, list []Node) []Node { … }