Module Flambda_utils

Utility functions for the Flambda intermediate language.

Access functions

find_declaration f decl raises Not_found if f is not in decl.

val find_declaration_variable : Closure_id.t -> Flambda.function_declarations -> Variable.t

find_declaration_variable f decl raises Not_found if f is not in decl.

find_free_variable v clos raises Not_found if c is not in clos.

Utility functions

val function_arity : Flambda.function_declaration -> int
val variables_bound_by_the_closure : Closure_id.t -> Flambda.function_declarations -> Variable.Set.t

Variables "bound by a closure" are those variables free in the corresponding function's body that are neither:

  • bound as parameters of that function; nor
  • bound by the let binding that introduces the function declaration(s). In particular, if f, g and h are being introduced by a simultaneous, possibly mutually-recursive let binding then none of f, g or h are bound in any of the closures for f, g and h.
val can_be_merged : Flambda.t -> Flambda.t -> bool

If can_be_merged f1 f2 is true, it is safe to merge switch branches containing f1 and f2.

val description_of_toplevel_node : Flambda.t -> string
val make_closure_declaration : is_classic_mode:bool -> id:Variable.t -> body:Flambda.t -> params:Parameter.t list -> stub:bool -> Flambda.t
val toplevel_substitution : Variable.t Variable.Map.t -> Flambda.expr -> Flambda.expr
val toplevel_substitution_named : Variable.t Variable.Map.t -> Flambda.named -> Flambda.named
val bind : bindings:(Variable.t * Flambda.named) list -> body:Flambda.t -> Flambda.t

bind [var1, expr1; ...; varN, exprN] body binds using Immutable Let expressions the given (var, expr) pairs around the body.

val name_expr_from_var : var:Variable.t -> Flambda.named -> Flambda.t
val initialize_symbols : Flambda.program -> (Symbol.t * Tag.t * Flambda.t list) list
val imported_symbols : Flambda.program -> Symbol.Set.t
val needed_import_symbols : Flambda.program -> Symbol.Set.t
val introduce_needed_import_symbols : Flambda.program -> Flambda.program
val root_symbol : Flambda.program -> Symbol.t
val might_raise_static_exn : Flambda.named -> Static_exception.t -> bool

Returns true iff the given term might raise the given static exception.

Creates a map from closure IDs to set_of_closure IDs by iterating over all sets of closures in the given program.

val all_lifted_constants : Flambda.program -> (Symbol.t * Flambda.constant_defining_value) list

The definitions of all constants that have been lifted out to Let_symbol or Let_rec_symbol constructions.

val all_lifted_constants_as_map : Flambda.program -> Flambda.constant_defining_value Symbol.Map.t

Like all_lifted_constant_symbols, but returns a map instead of a list.

val all_lifted_constant_sets_of_closures : Flambda.program -> Set_of_closures_id.Set.t

The identifiers of all constant sets of closures that have been lifted out to Let_symbol or Let_rec_symbol constructions.

val all_lifted_constant_closures : Flambda.program -> Closure_id.Set.t
val all_sets_of_closures : Flambda.program -> Flambda.set_of_closures list

All sets of closures in the given program (whether or not bound to a symbol.)

val substitute_read_symbol_field_for_variables : (Symbol.t * int list) Variable.Map.t -> Flambda.t -> Flambda.t
module Switch_storer : sig ... end

For the compilation of switch statements.

val fun_vars_referenced_in_decls : Flambda.function_declarations -> closure_symbol:(Closure_id.t -> Symbol.t) -> Variable.Set.t Variable.Map.t

Within a set of function declarations there is a set of function bodies, each of which may (or may not) reference one of the other functions in the same set. Initially such intra-set references are by Vars (known as "fun_var"s) but if the function is lifted by Lift_constants then the references will be translated to Symbols. This means that optimization passes that need to identify whether a given "fun_var" (i.e. a key in the funs map in a value of type function_declarations) is used in one of the function bodies need to examine the free_symbols as well as the free_variables members of function_declarations. This function makes that process easier by computing all used "fun_var"s in the bodies of the given set of function declarations, including the cases where the references are Symbols. The returned value is a map from "fun_var"s to the "fun_var"s (if any) used in the body of the function associated with that "fun_var".

val closures_required_by_entry_point : entry_point:Closure_id.t -> closure_symbol:(Closure_id.t -> Symbol.t) -> Flambda.function_declarations -> Variable.Set.t

Computes the set of closure_id in the set of closures that are required used (transitively) the entry_point

val all_functions_parameters : Flambda.function_declarations -> Variable.Set.t
val contains_stub : Flambda.function_declarations -> bool
val projection_to_named : Projection.t -> Flambda.named
type specialised_to_same_as =
| Not_specialised
| Specialised_and_aliased_to of Variable.Set.t
val parameters_specialised_to_the_same_variable : function_decls:Flambda.function_declarations -> specialised_args:Flambda.specialised_to Variable.Map.t -> specialised_to_same_as list Variable.Map.t

For each parameter in a given set of function declarations and the usual specialised-args mapping, determine which other parameters are specialised to the same variable as that parameter. The result is presented as a map from fun_vars to lists, corresponding componentwise to the usual params list in the corresponding function declaration.