145 lines
5.6 KiB
OCaml
145 lines
5.6 KiB
OCaml
(***********************************************************************)
|
|
(* *)
|
|
(* Objective Caml *)
|
|
(* *)
|
|
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
|
|
(* *)
|
|
(* Copyright 1996 Institut National de Recherche en Informatique et *)
|
|
(* en Automatique. All rights reserved. This file is distributed *)
|
|
(* under the terms of the GNU Library General Public License, with *)
|
|
(* the special exception on linking described in file ../LICENSE. *)
|
|
(* *)
|
|
(***********************************************************************)
|
|
|
|
(* $Id$ *)
|
|
|
|
(** 32-bit integers.
|
|
|
|
This module provides operations on the type [int32]
|
|
of signed 32-bit integers. Unlike the built-in [int] type,
|
|
the type [int32] is guaranteed to be exactly 32-bit wide on all
|
|
platforms. All arithmetic operations over [int32] are taken
|
|
modulo 2{^32}.
|
|
|
|
Performance notice: values of type [int32] occupy more memory
|
|
space than values of type [int], and arithmetic operations on
|
|
[int32] are generally slower than those on [int]. Use [int32]
|
|
only when the application requires exact 32-bit arithmetic. *)
|
|
|
|
val zero : int32
|
|
(** The 32-bit integer 0. *)
|
|
|
|
val one : int32
|
|
(** The 32-bit integer 1. *)
|
|
|
|
val minus_one : int32
|
|
(** The 32-bit integer -1. *)
|
|
|
|
external neg : int32 -> int32 = "%int32_neg"
|
|
(** Unary negation. *)
|
|
|
|
external add : int32 -> int32 -> int32 = "%int32_add"
|
|
(** Addition. *)
|
|
|
|
external sub : int32 -> int32 -> int32 = "%int32_sub"
|
|
(** Subtraction. *)
|
|
|
|
external mul : int32 -> int32 -> int32 = "%int32_mul"
|
|
(** Multiplication. *)
|
|
|
|
external div : int32 -> int32 -> int32 = "%int32_div"
|
|
(** Integer division. Raise [Division_by_zero] if the second
|
|
argument is zero. *)
|
|
|
|
external rem : int32 -> int32 -> int32 = "%int32_mod"
|
|
(** Integer remainder. If [x >= 0] and [y > 0], the result
|
|
of [Int32.rem x y] satisfies the following properties:
|
|
[0 <= Int32.rem x y < y] and
|
|
[x = Int32.add (Int32.mul (Int32.div x y) y) (Int32.rem x y)].
|
|
If [y = 0], [Int32.rem x y] raises [Division_by_zero].
|
|
If [x < 0] or [y < 0], the result of [Int32.rem x y] is
|
|
not specified and depends on the platform. *)
|
|
|
|
val succ : int32 -> int32
|
|
(** Successor. [Int32.succ x] is [Int32.add x Int32.one]. *)
|
|
|
|
val pred : int32 -> int32
|
|
(** Predecessor. [Int32.pred x] is [Int32.sub x Int32.one]. *)
|
|
|
|
val abs : int32 -> int32
|
|
(** Return the absolute value of its argument. *)
|
|
|
|
val max_int : int32
|
|
(** The greatest representable 32-bit integer, 2{^31} - 1. *)
|
|
|
|
val min_int : int32
|
|
(** The smallest representable 32-bit integer, -2{^31}. *)
|
|
|
|
|
|
external logand : int32 -> int32 -> int32 = "%int32_and"
|
|
(** Bitwise logical and. *)
|
|
|
|
external logor : int32 -> int32 -> int32 = "%int32_or"
|
|
(** Bitwise logical or. *)
|
|
|
|
external logxor : int32 -> int32 -> int32 = "%int32_xor"
|
|
(** Bitwise logical exclusive or. *)
|
|
|
|
val lognot : int32 -> int32
|
|
(** Bitwise logical negation *)
|
|
|
|
external shift_left : int32 -> int -> int32 = "%int32_lsl"
|
|
(** [Int32.shift_left x y] shifts [x] to the left by [y] bits.
|
|
The result is unspecified if [y < 0] or [y >= 32]. *)
|
|
|
|
external shift_right : int32 -> int -> int32 = "%int32_asr"
|
|
(** [Int32.shift_right x y] shifts [x] to the right by [y] bits.
|
|
This is an arithmetic shift: the sign bit of [x] is replicated
|
|
and inserted in the vacated bits.
|
|
The result is unspecified if [y < 0] or [y >= 32]. *)
|
|
|
|
external shift_right_logical : int32 -> int -> int32 = "%int32_lsr"
|
|
(** [Int32.shift_right_logical x y] shifts [x] to the right by [y] bits.
|
|
This is a logical shift: zeroes are inserted in the vacated bits
|
|
regardless of the sign of [x].
|
|
The result is unspecified if [y < 0] or [y >= 32]. *)
|
|
|
|
external of_int : int -> int32 = "%int32_of_int"
|
|
(** Convert the given integer (type [int]) to a 32-bit integer (type [int32]). *)
|
|
|
|
external to_int : int32 -> int = "%int32_to_int"
|
|
(** Convert the given 32-bit integer (type [int32]) to an
|
|
integer (type [int]). On 32-bit platforms, the 32-bit integer
|
|
is taken modulo 2{^31}, i.e. the high-order bit is lost
|
|
during the conversion. On 64-bit platforms, the conversion
|
|
is exact. *)
|
|
|
|
external of_float : float -> int32 = "int32_of_float"
|
|
(** Convert the given floating-point number to a 32-bit integer,
|
|
discarding the fractional part (truncate towards 0).
|
|
The result of the conversion is undefined if, after truncation,
|
|
the number is outside the range \[{!Int32.min_int}, {!Int32.max_int}\]. *)
|
|
|
|
external to_float : int32 -> float = "int32_to_float"
|
|
(** Convert the given 32-bit integer to a floating-point number. *)
|
|
|
|
external of_string : string -> int32 = "int32_of_string"
|
|
(** Convert the given string to a 32-bit integer.
|
|
The string is read in decimal (by default) or in hexadecimal,
|
|
octal or binary if the string begins with [0x], [0o] or [0b]
|
|
respectively.
|
|
Raise [Failure "int_of_string"] if the given string is not
|
|
a valid representation of an integer. *)
|
|
|
|
val to_string : int32 -> string
|
|
(** Return the string representation of its argument, in signed decimal. *)
|
|
|
|
external format : string -> int32 -> string = "int32_format"
|
|
(** [Int32.format fmt n] return the string representation of the
|
|
32-bit integer [n] in the format specified by [fmt].
|
|
[fmt] is a [Printf]-style format containing exactly
|
|
one [%d], [%i], [%u], [%x], [%X] or [%o] conversion specification.
|
|
This function is deprecated; use {!Printf.sprintf} with a [%lx] format
|
|
instead. *)
|
|
|