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include module type of struct include Hardcaml.Bits end
val compare : t -> t -> Base.Int.t
include Hardcaml.Comb.S with type t := t
val sexp_of_t : t -> Ppx_sexp_conv_lib.Sexp.t
include Base.Equal.S with type t := t
val equal : t Base.Equal.equal
val empty : t

the empty signal

val is_empty : t -> Base.Bool.t
val (--) : t -> Base.String.t -> t

names a signal

let a = a -- "a" in ...

signals may have multiple names.

val width : t -> Base.Int.t

returns the width (number of bits) of a signal.

let w = width s in ...

val address_bits_for : Base.Int.t -> Base.Int.t

addess_bits_for num_elements returns the address width required to index num_elements.

It is the same as Int.ceil_log2, except it wll return a minimum value of 1 (since you cannot have 0 width vectors). Raises if num_elements is < 0.

val num_bits_to_represent : Base.Int.t -> Base.Int.t

num_bits_to_represent x returns the number of bits required to represent the number x, which should be >= 0.

val of_constant : Hardcaml.Constant.t -> t
val to_constant : t -> Hardcaml.Constant.t
val constb : Base.String.t -> t

convert binary string to constant

val consti : width:Base.Int.t -> Base.Int.t -> t

convert integer to constant

val consti32 : width:Base.Int.t -> Base.Int32.t -> t
val consti64 : width:Base.Int.t -> Base.Int64.t -> t
val consthu : width:Base.Int.t -> Base.String.t -> t

convert unsigned hex string to constant

val consths : width:Base.Int.t -> Base.String.t -> t

convert signed hex string to constant

val constd : width:Base.Int.t -> Base.String.t -> t

convert decimal string to constant

val constv : Base.String.t -> t

convert verilog style string to constant

val constibl : Base.Int.t Base.List.t -> t

convert IntbitsList to constant

val const : Base.String.t -> t

convert verilog style or binary string to constant

val concat : t Base.List.t -> t

concat ts concatenates a list of signals - the msb of the head of the list will become the msb of the result.

let c = concat [ a; b; c ] in ...

concat raises if ts is empty or if any t in ts is empty.

val concat_e : t Base.List.t -> t

same as concat except empty signals are first filtered out

val (@:) : t -> t -> t

concatenate two signals.

let c = a @: b in ...

equivalent to concat [ a; b ]

val vdd : t

logic 1

val is_vdd : t -> Base.Bool.t
val gnd : t

logic 0

val is_gnd : t -> Base.Bool.t
val zero : Base.Int.t -> t

zero w makes a the zero valued constant of width w

val ones : Base.Int.t -> t

ones w makes a constant of all ones of width w

val one : Base.Int.t -> t

one w makes a one valued constant of width w

val select : t -> Base.Int.t -> Base.Int.t -> t

select t hi lo selects from t bits in the range hi...lo, inclusive. select raises unless hi and lo fall within 0 .. width t - 1 and hi >= lo.

val select_e : t -> Base.Int.t -> Base.Int.t -> t

same as select except invalid indices return empty

val bit : t -> Base.Int.t -> t

select a single bit

val msb : t -> t

get most significant bit

val lsbs : t -> t

get least significant bits

val lsb : t -> t

get least significant bit

val msbs : t -> t

get most significant bits

val drop_bottom : t -> Base.Int.t -> t

drop_bottom s n drop bottom n bits of s

val drop_top : t -> Base.Int.t -> t

drop_top s n drop top n bits of s

val sel_bottom : t -> Base.Int.t -> t

sel_bottom s n select bottom n bits of s

val sel_top : t -> Base.Int.t -> t

sel_top s n select top n bits of s

val insert : into:t -> t -> at_offset:Base.Int.t -> t

insert ~into:t x ~at_offset insert x into t at given offet

val sel : t -> (Base.Int.t * Base.Int.t) -> t
val mux : t -> t Base.List.t -> t

multiplexer.

let m = mux sel inputs in ...

Given l = List.length inputs and w = width sel the following conditions must hold.

l <= 2**w, l >= 2

If l < 2**w, the last input is repeated.

All inputs provided must have the same width, which will in turn be equal to the width of m.

val mux2 : t -> t -> t -> t

mux2 c t f 2 input multiplexer. Selects t if c is high otherwise f.

t and f must have same width and c must be 1 bit.

Equivalent to mux c [f; t]

val mux_init : t -> Base.Int.t -> f:(Base.Int.t -> t) -> t
val cases : t -> t -> (Base.Int.t * t) Base.List.t -> t

case mux

val matches : ?resize:(t -> Base.Int.t -> t) -> ?default:t -> t -> (Base.Int.t * t) Base.List.t -> t

match mux

val (&:) : t -> t -> t

logical and

val (&:.) : t -> Base.Int.t -> t
val (&&:) : t -> t -> t

a <>:. 0 &: b <>:. 0

val (|:) : t -> t -> t

logical or

val (|:.) : t -> Base.Int.t -> t
val (||:) : t -> t -> t

a <>:. 0 |: b <>:. 0

val (^:) : t -> t -> t

logic xor

val (^:.) : t -> Base.Int.t -> t
val (~:) : t -> t

logical not

val (+:) : t -> t -> t

addition

val (+:.) : t -> Base.Int.t -> t
val (-:) : t -> t -> t

subtraction

val (-:.) : t -> Base.Int.t -> t
val negate : t -> t

negation

val (*:) : t -> t -> t

unsigned multiplication

val (*+) : t -> t -> t

signed multiplication

val (==:) : t -> t -> t

equality

val (==:.) : t -> Base.Int.t -> t
val (<>:) : t -> t -> t

inequality

val (<>:.) : t -> Base.Int.t -> t
val (<:) : t -> t -> t

less than

val (<:.) : t -> Base.Int.t -> t
val lt : t -> t -> t
val (>:) : t -> t -> t

greater than

val (>:.) : t -> Base.Int.t -> t
val (<=:) : t -> t -> t

less than or equal to

val (<=:.) : t -> Base.Int.t -> t
val (>=:) : t -> t -> t

greater than or equal to

val (>=:.) : t -> Base.Int.t -> t
val (<+) : t -> t -> t

signed less than

val (<+.) : t -> Base.Int.t -> t
val (>+) : t -> t -> t

signed greater than

val (>+.) : t -> Base.Int.t -> t
val (<=+) : t -> t -> t

signed less than or equal to

val (<=+.) : t -> Base.Int.t -> t
val (>=+) : t -> t -> t

signed greated than or equal to

val (>=+.) : t -> Base.Int.t -> t
val to_string : t -> Base.String.t

create string from signal

val to_int : t -> Base.Int.t

to_int t treats t as unsigned and resizes it to fit exactly within an OCaml Int.t.

  • If width t > Int.num_bits then the upper bits are truncated.
  • If width t >= Int.num_bits and bit t (Int.num_bits-1) = vdd (i.e. the msb of the resulting Int.t is set), then the result is negative.
  • If t is Signal.t and not a constant value, an exception is raised.
val to_sint : t -> Base.Int.t

to_sint t treats t as signed and resizes it to fit exactly within an OCaml Int.t.

  • If width t > Int.num_bits then the upper bits are truncated.
  • If t is Signal.t and not a constant value, an exception is raised.
val to_int32 : t -> Base.Int32.t
val to_sint32 : t -> Base.Int32.t
val to_int64 : t -> Base.Int64.t
val to_sint64 : t -> Base.Int64.t
val to_bstr : t -> Base.String.t

create binary string from signal

val bits : t -> t Base.List.t

convert signal to a list of bits, msb first

val to_array : t -> t Base.Array.t

to_array s convert signal s to array of bits with lsb at index 0

val of_array : t Base.Array.t -> t

of_array a convert array a of bits to signal with lsb at index 0

val repeat : t -> Base.Int.t -> t

repeat signal n times

val split_in_half : t -> t * t

split signal in half

val split : ?exact:Base.Bool.t -> part_width:Base.Int.t -> t -> t Base.List.t

Split signal into a list of signals with width equal to part_width. The least significant bits are at the head of the returned list. If exact is true the input signal width must be exactly divisable by part_width.

val sll : t -> Base.Int.t -> t

shift left logical

val srl : t -> Base.Int.t -> t

shift right logical

val sra : t -> Base.Int.t -> t

shift right arithmetic

val log_shift : (t -> Base.Int.t -> t) -> t -> t -> t

shift by variable amount

val uresize : t -> Base.Int.t -> t

uresize t w returns the unsigned resize of t to width w. If w = width t, this is a no-op. If w < width t, this selects the w low bits of t. If w > width t, this extends t with zero (width t - w).

val sresize : t -> Base.Int.t -> t

sresize t w returns the signed resize of t to width w. If w = width t, this is a no-op. If w < width t, this selects the w low bits of t. If w > width t, this extends t with width t - w copies of msb t.

val ue : t -> t

unsigned resize by +1 bit

val se : t -> t

signed resize by +1 bit

val resize_list : resize:(t -> Base.Int.t -> t) -> t Base.List.t -> t Base.List.t

resize_list ?resize l finds the maximum width in l and applies resize el max to each element.

val resize_op2 : resize:(t -> Base.Int.t -> t) -> (t -> t -> t) -> t -> t -> t

resize_op2 ~resize f a b applies resize x w to a and b where w is the maximum of their widths. It then returns f a b

val reduce : f:('a -> 'a -> 'a) -> 'a Base.List.t -> 'a

fold 'op' though list

val reverse : t -> t

reverse bits

val mod_counter : max:Base.Int.t -> t -> t

mod_counter max t is if t = max then 0 else (t + 1), and can be used to count from 0 to (max-1) then from zero again. If max == 1<<n, then a comparator is not generated and overflow arithmetic used instead. If

val tree : arity:Base.Int.t -> f:('a Base.List.t -> 'a) -> 'a Base.List.t -> 'a

tree ~arity ~f input creates a tree of operations. The arity of the operator is configurable. tree raises if input = [].

val priority_select : ?branching_factor:Base.Int.t -> t Hardcaml.With_valid.t Base.List.t -> t Hardcaml.With_valid.t

priority_select cases returns the value associated with the first case whose valid signal is high. valid will be set low in the returned With_valid.t if no case is selected.

val priority_select_with_default : ?branching_factor:Base.Int.t -> t Hardcaml.With_valid.t Base.List.t -> default:t -> t

Same as priority_select except returns default if no case matches.

val onehot_select : ?branching_factor:Base.Int.t -> t Hardcaml.With_valid.t Base.List.t -> t

Select a case where one and only one valid signal is enabled. If more than one case is valid then the return value is undefined. If no cases are valid, 0 is returned by the current implementation, though this should not be relied upon.

val popcount : ?branching_factor:Base.Int.t -> t -> t

popcount t returns the number of bits set in t.

val is_pow2 : ?branching_factor:Base.Int.t -> t -> t

is_pow2 t returns a bit to indicate if t is a power of 2.

val leading_ones : ?branching_factor:Base.Int.t -> t -> t

leading_ones t returns the number of consecutive 1s from the most significant bit of t down.

val trailing_ones : ?branching_factor:Base.Int.t -> t -> t

trailing_ones t returns the number of consecutive 1s from the least significant bit of t up.

val leading_zeros : ?branching_factor:Base.Int.t -> t -> t

leading_zeros t returns the number of consecutive 0s from the most significant bit of t down.

val trailing_zeros : ?branching_factor:Base.Int.t -> t -> t

trailing_zeros t returns the number of consecutive 0s from the least significant bit of t up.

val floor_log2 : ?branching_factor:Base.Int.t -> t -> t Hardcaml.With_valid.t

floor_log2 x returns the floor of log-base-2 of x. x is treated as unsigned and an error is indicated by valid = gnd in the return value if x = 0.

val ceil_log2 : ?branching_factor:Base.Int.t -> t -> t Hardcaml.With_valid.t

ceil_log2 x returns the ceiling of log-base-2 of x. x is treated as unsigned and an error is indicated by valid = gnd in the return value if x = 0.

val binary_to_onehot : t -> t

convert binary to onehot

val onehot_to_binary : t -> t

convert onehot to binary

val binary_to_gray : t -> t

convert binary to gray code

val gray_to_binary : t -> t

convert gray code to binary

val random : width:Base.Int.t -> t

create random constant vector of given width

module type TypedMath = Hardcaml.Bits.TypedMath
module Unsigned = Hardcaml.Bits.Unsigned
module Signed = Hardcaml.Bits.Signed
module Uop = Hardcaml.Bits.Uop

Unsigned operations compatible with type t

module Sop = Hardcaml.Bits.Sop

Signed operations compatible with type t

include Base.Comparator.S with type t := t
type comparator_witness = Hardcaml.Bits.comparator_witness
module Mutable = Hardcaml.Bits.Mutable

Mutable is a mutable bits used by Cyclesim for efficiency.

Pretty printer.

val to_hstr : t -> String.t
val to_ustr : t -> string
val to_sstr : t -> String.t