Frama-C API - Alpha

Alpha conversion.

type 'a undoAlphaElement

This is the type of the elements that are recorded by the alpha conversion functions in order to be able to undo changes to the tables they modify. Useful for implementing scoping

type 'a alphaTableData

This is the type of the elements of the alpha renaming table. These elements can carry some data associated with each occurrence of the name.

type 'a alphaTable = (string, (string, 'a alphaTableData Stdlib.ref) Stdlib.Hashtbl.t) Stdlib.Hashtbl.t

type for alpha conversion table. We split the lookup in two to avoid creating accidental collisions when converting x_0 into x_0_0 if the original code contains both.

val newAlphaName : alphaTable:'a alphaTable -> undolist:'a undoAlphaElement list Stdlib.ref option -> lookupname:string -> data:'a -> string * 'a

Create a new name based on a given name. The new name is formed from a prefix (obtained from the given name by stripping a suffix consisting of _ followed by only digits), followed by a special separator and then by a positive integer suffix. The first argument is a table mapping name prefixes to some data that specifies what suffixes have been used and how to create the new one. This function updates the table with the new largest suffix generated. The "undolist" argument, when present, will be used by the function to record information that can be used by Alpha.undoAlphaChanges to undo those changes. Note that the undo information will be in reverse order in which the action occurred. Returns the new name and, if different from the lookupname, the location of the previous occurrence. This function knows about the location implicitly from the (Current_loc.get ()).

val registerAlphaName : alphaTable:'a alphaTable -> lookupname:string -> data:'a -> unit

Register a name with an alpha conversion table to ensure that when later we call newAlphaName we do not end up generating this one

val getAlphaPrefix : lookupname:string -> string * string

Split the name in preparation for newAlphaName. Returns a pair (prefix, infix) where prefix is the index in the outer table, while infix is the index in the inner table.

val undoAlphaChanges : alphaTable:'a alphaTable -> undolist:'a undoAlphaElement list -> unit

Undo the changes to a table