Module Bit_utils

module Bit_utils: sig .. end
Some bit manipulations.

val sizeofchar : unit -> Integer.t
sizeof(char) in bits
val sizeofpointer : unit -> int
sizeof(char* ) in bits
val sizeof : Cil_types.typ -> Int_Base.t
sizeof ty is the size of ty in bits. This function may return Int_Base.top.
val osizeof : Cil_types.typ -> Int_Base.t
osizeof ty is the size of ty in bytes. This function may return Int_Base.top.
exception Neither_Int_Nor_Enum_Nor_Pointer
val is_signed_int_enum_pointer : Cil_types.typ -> bool
true means that the type is signed.
Raises Neither_Int_Nor_Enum_Nor_Pointer if the sign of the type is not meaningful.
val signof_typeof_lval : Cil_types.lval -> bool
Returns the sign of type of the lval. true means that the type is signed.
val sizeof_vid : Cil_types.varinfo -> Int_Base.t
Returns the size of the type of the variable in bits.
val sizeof_lval : Cil_types.lval -> Int_Base.t
Returns the size of the type of the left value in bits.
val sizeof_pointed : Cil_types.typ -> Int_Base.t
Returns the size of the type pointed by a pointer or array type in bits. Never call it on a non pointer or non array type .
val osizeof_pointed : Cil_types.typ -> Int_Base.t
Returns the size of the type pointed by a pointer or array type in bytes. Never call it on a non pointer or array type.
val sizeof_pointed_lval : Cil_types.lval -> Int_Base.t
Returns the size of the type pointed by a pointer type of the lval in bits. Never call it on a non pointer type lval.
val max_bit_address : unit -> Integer.t
Returns the maximal possible offset in bits of a memory base.
val max_bit_size : unit -> Integer.t
Returns the maximal possible size in bits of a memory base.
val max_byte_address : unit -> Integer.t
Since Aluminium-20160501
Returns the maximal possible offset in bytes of a memory base.
val max_byte_size : unit -> Integer.t
Since Aluminium-20160501
Returns the maximal possible size in bytes of a memory base.

Pretty printing


val pretty_bits : Cil_types.typ ->
use_align:bool ->
align:Abstract_interp.Rel.t ->
rh_size:Integer.t ->
start:Integer.t ->
stop:Integer.t -> Format.formatter -> bool * Cil_types.typ option
Pretty prints a range of bits in a type for the user. Tries to find field names and array indexes, whenever possible.

Mapping from numeric offsets to symbolic ones.


type offset_match = 
| MatchType of Cil_types.typ (*
Offset that has this type (modulo attributes)
*)
| MatchSize of Integer.t (*
Offset that has a type of this size
*)
| MatchFirst (*
Return first symbolic offset that matches
*)
We want to find a symbolic offset that corresponds to a numeric one, with one additional criterion:
exception NoMatchingOffset
val find_offset : Cil_types.typ ->
offset:Integer.t ->
offset_match -> Cil_types.offset * Cil_types.typ
find_offset typ ~offset ~size finds a subtype t of typ that describes the type of the bits offset..offset+size-1 in typ. May return a subtype of typ, or a type that is a sub-array of an array type in typ. Also returns a Cil_types.offset off that corresponds to offset. (But we do not have the guarantee that typeof(off) == typ, because of sub-arrays.)
Raises NoMatchingOffset when no offset matches.