Std.Sub
Subroutine.
Subroutine is a set of blocks. The first block of a function is considered an entry block.
longer mangled every time the program is updated. It is done only once when the program is lifted (see Program.lift
).
create ?name ()
creates a new subroutine.
Creates a subroutine that includes given arguments and blocks. The order of the terms is preserved with the first block being the entry block. No references between blocks are added, so the blocks shall be correctly linked and be reachable from the entry block.
If tid
is not specied then a fresh one is generated. if name
is not specified then a fresh name is derived from the tid
.
lift entry
takes an basic block of assembler instructions, as an entry and lifts it to the subroutine term.
val name : t -> string
name sub
returns a subroutine name
ssa sub
returns sub
in SSA form. If program is already in SSA, then do nothing (see also is_ssa
). The underlying algorithm produces a semi-pruned SSA form. To represent different versions of the same variable we use variable versions. Any definition of a variable increases its version number. So, the zero version is reserved for variables that weren't defined before the first use.
val is_ssa : t -> bool
is_ssa sub
is true
if sub
was transformed into an SSA form. This is O(1) predicate that doesn't really check, that a subroutine is in an SSA form, so it is a responsibility of a user to preserve the SSA form on any transformation.
free_vars sub
computes a set of variables that are free in a given subroutine sub
. The variable is considered free if it is used before defined or is not locally bound. If sub
is in an SSA form, then the set is computed trivially, thanks to a naming scheme. If program is not in an SSA form, then a BFS on a dominators tree is used.
val to_graph : t -> Graphs.Tid.t
to_graph sub
builds a graph of subroutine sub
.
Graph nodes are block term identifiers and edges are labeled with term identifiers of the jmp terms that correspond to the given edge.
Graphs.Tid.start
and Graphs.Tid.exit
so that all nodes that has in-degree 0
or that start a strongly connected component are connected to the start
node (the same for exit
but on the reversed graph.
Edges from start
to other nodes are labeled with the Graphs.Tid.start
tid.
Edges from nodes to the exit
node are labeled with the Graphs.Tid.exit
tid.
val to_cfg : t -> Graphs.Ir.t
to_cfg sub
builds a graph representation of a subroutine sub
. All graph operations are mapped to corresponding Term
operations. See Graphlib
.Ir for more information.
val of_cfg : Graphs.Ir.t -> t
of_cfg cfg
extracts a sub term
from a given graph cfg
. Since Graphlib
.Ir module builds term incrementally this operation is just a projection, i.e., it has O(0) complexity.
val compute_liveness : t -> (tid, Var.Set.t) Graphlib.Std.Solution.t
compute_liveness sub
computes a set of live variables for each block.
For a block b
and solution s = compute_liveness sub
, Solution.get s (Term.tid b)
is a set of variables that are live at the _exit_ from this block.
A set of variables that are live (free) in the whole subroutine is the set of variables that are live at the Graphs.Tid.start
node.
When the subroutine is in the SSA form then the phi-nodes have the following semantics.
Informally, a phi-node defines the values on the corresponding edges of the predecessors.
flatten sub
returns sub
in flattened form in which all operands are trivial. @see Blk.flatten for more information about flattening.
val aliases : string list tag
other names for the given subroutine.
val const : unit tag
A subroutine doesn't examine any values except its arguments, and have no effects except the return value. Basically this is just slightly more strict class than the pure attribute below, since function is not allowed to read global memory. Note that a function that has pointer arguments and examines the data pointed to is not const. Likewise, a function that calls a non-const function usually is not be const. It does not make sense for a const function to return void
val pure : unit tag
A subroutine have no effects except the return value and their return value depends only on the parameters and/or global variables.
val stub : unit tag
A subroutine is a stub
val extern : unit tag
A subroutine is visible outside of the compilation unit
val leaf : unit tag
a subroutine doesn't contain any calls in any disguise, i.e., no longjmps, indirect calls, exceptions, etc.
val malloc : unit tag
A subroutine is malloc-like, i.e., the pointer P returned by the subroutine cannot alias any other pointer valid when the function returns, and moreover no pointers to valid objects occur in any storage addressed by P.
val noreturn : unit tag
A subroutine will not return (either loop infinitely or abort a program)
val returns_twice : unit tag
A subroutine may return more than one time. Examples of such functions are setjmp and vfork
val nothrow : unit tag
A subroutine doesn't throw exceptions
val entry_point : unit tag
a subroutine is the binary entry point
val intrinsic : unit tag
a subroutine is an intrinisic or special instruction not a real subroutine.
module Builder : sig ... end
Subroutine builder
module KB : sig ... end
val pp_slots : string list -> Stdlib.Format.formatter -> t -> unit
pp_slots names
prints slots that are in names
.
include Regular.Std.Regular.S with type t := t
include Core_kernel.Bin_prot.Binable.S with type t := t
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (int -> t) Bin_prot.Read.reader
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_reader_t : t Bin_prot.Type_class.reader
val bin_t : t Bin_prot.Type_class.t
include Regular.Std.Printable.S with type t := t
val to_string : t -> string
to_string x
returns a human-readable representation of x
val str : unit -> t -> string
str () t
is formatted output function that matches "%a" conversion format specifier in functions, that prints to string, e.g., sprintf
, failwithf
, errorf
and, surprisingly all Lwt
printing function, including Lwt_io.printf
and logging (or any other function with type ('a,unit,string,...) formatN`. Example:
Or_error.errorf "type %a is not valid for %a"
Type.str ty Exp.str exp
val pps : unit -> t -> string
synonym for str
val ppo : Core_kernel.Out_channel.t -> t -> unit
will print to a standard output_channel
, useful for using in printf
, fprintf
, etc.
val pp_seq : Stdlib.Format.formatter -> t Core_kernel.Sequence.t -> unit
prints a sequence of values of type t
this will include pp
function from Core
that has type t printer
, and can be used in Format.printf
family of functions
include Core_kernel.Pretty_printer.S with type t := t
val pp : Base__.Formatter.t -> t -> unit
include Core_kernel.Comparable.S_binable with type t := t
module Replace_polymorphic_compare : sig ... end
val comparator : (t, comparator_witness) Core_kernel__.Comparator.comparator
module Map : sig ... end
module Set : sig ... end
include Core_kernel.Hashable.S_binable with type t := t
val hash_fold_t :
Ppx_hash_lib.Std.Hash.state ->
t ->
Ppx_hash_lib.Std.Hash.state
val hash : t -> Ppx_hash_lib.Std.Hash.hash_value
val hashable : t Core_kernel__.Hashtbl.Hashable.t
module Table : sig ... end
module Hash_set : sig ... end
module Hash_queue : sig ... end
include Regular.Std.Data.S with type t := t
name,Ver v,desc
information attached to a particular reader or writer.
Data representation version. After any change in data representation the version should be increased.
Serializers that are derived from a data representation must have the same version as a version of the data structure, from which it is derived. This kind of serializers can only read and write data of the same version.
Other serializers can actually read and write data independent on its representation version. A serializer, that can't store data of current version simply shouldn't be added to a set of serializers.
It is assumed, that if a reader and a writer has the same name and version, then whatever was written by the writer should be readable by the reader. The round-trip equality is not required, thus it is acceptable if some information is lost.
It is also possible, that a reader and a writer that has the same name are compatible. In that case it is recommended to use semantic versioning.
val size_in_bytes : ?ver:string -> ?fmt:string -> t -> int
size_in_bytes ?ver ?fmt datum
returns the amount of bytes that is needed to represent datum
in the given format and version
val of_bytes : ?ver:string -> ?fmt:string -> Regular.Std.bytes -> t
of_bytes ?ver ?fmt bytes
deserializes a value from bytes.
val to_bytes : ?ver:string -> ?fmt:string -> t -> Regular.Std.bytes
to_bytes ?ver ?fmt datum
serializes a datum
to a sequence of bytes.
val blit_to_bytes :
?ver:string ->
?fmt:string ->
Regular.Std.bytes ->
t ->
int ->
unit
blit_to_bytes ?ver ?fmt buffer datum offset
copies a serialized representation of datum into a buffer
, starting from the offset
.
val of_bigstring : ?ver:string -> ?fmt:string -> Core_kernel.bigstring -> t
of_bigstring ?ver ?fmt buf
deserializes a datum from bigstring
val to_bigstring : ?ver:string -> ?fmt:string -> t -> Core_kernel.bigstring
of_bigstring ?ver ?fmt datum
serializes a datum to a sequence of bytes represented as bigstring
val blit_to_bigstring :
?ver:string ->
?fmt:string ->
Core_kernel.bigstring ->
t ->
int ->
unit
blit_to_bigstring ?ver ?fmt buffer datum offset
copies a serialized representation of datum into a buffer
, starting from offset
.
module Io : sig ... end
Input/Output functions for the given datum.
module Cache : sig ... end
Data cache.
val add_reader :
?desc:string ->
ver:string ->
string ->
t Regular.Std.reader ->
unit
add_reader ?desc ~ver name reader
registers a new reader
with a provided name
, version ver
and optional description desc
val add_writer :
?desc:string ->
ver:string ->
string ->
t Regular.Std.writer ->
unit
add_writer ?desc ~ver name writer
registers a new writer
with a provided name
, version ver
and optional description desc
val available_readers : unit -> info list
available_reader ()
lists available readers for the data type
val default_reader : unit -> info
default_reader
returns information about default reader
set_default_reader ?ver name
sets new default reader. If version is not specified then the latest available version is used. Raises an exception if a reader with a given name doesn't exist.
with_reader ?ver name operation
temporary sets a default reader to a reader with a specified name and version. The default reader is restored after operation
is finished.
val available_writers : unit -> info list
available_writer ()
lists available writers for the data type
val default_writer : unit -> info
default_writer
returns information about the default writer
set_default_writer ?ver name
sets new default writer. If version is not specified then the latest available version is used. Raises an exception if a writer with a given name doesn't exist.
with_writer ?ver name operation
temporary sets a default writer to a writer with a specified name and version. The default writer is restored after operation
is finished.
val default_printer : unit -> info option
default_writer
optionally returns an information about default printer
set_default_printer ?ver name
sets new default printer. If version is not specified then the latest available version is used. Raises an exception if a printer with a given name doesn't exist.
with_printer ?ver name operation
temporary sets a default printer to a printer with a specified name and version. The default printer is restored after operation
is finished.
val find_reader : ?ver:string -> string -> t Regular.Std.reader option
find_reader ?ver name
lookups a reader with a given name. If version is not specified, then a reader with maximum version is returned.
val find_writer : ?ver:string -> string -> t Regular.Std.writer option
find_writer ?ver name
lookups a writer with a given name. If version is not specified, then a writer with maximum version is returned.