'hwarith' Dialect

Types and operations for the HWArith dialect This dialect defines the HWArith dialect, modeling bit-width aware arithmetic operations.

Operations

hwarith.add (::circt::hwarith::AddOp)

Bitwidth-aware integer addition.

Syntax:

operation ::= `hwarith.add` $inputs attr-dict `:` functional-type($inputs, $result)

The add operation takes two operands and returns one result. The result type is inferred from the operand types, which may be signed or unsigned scalar integer types of arbitrary bitwidth.

Examples:

%0 = hwarith.add %10, %11 : (ui3, ui4) -> ui5
%1 = hwarith.add %12, %13 : (si3, si3) -> si4
%2 = hwarith.add %14, %15 : (ui3, si4) -> si5
%3 = hwarith.add %16, %17 : (si4, ui6) -> si8

Traits: AlwaysSpeculatableImplTrait, Commutative

Interfaces: ConditionallySpeculatable, InferTypeOpInterface, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Operands:

Results:

hwarith.cast (::circt::hwarith::CastOp)

Signedness-aware cast.

Syntax:

operation ::= `hwarith.cast` $in attr-dict `:` functional-type($in, $out)

The cast operation takes one operand and returns one result. Both, the result type and the operand type can be of any scalar integer type with arbitrary bitwidth. However, at least one of them needs to be a HWArithIntegerType.

†) prohibited because of the ambiguity whether a sign or a zero extension is required.

Examples:

%0 = hwarith.cast %10 : (ui3) -> si5
%1 = hwarith.cast %11 : (si3) -> si4
%2 = hwarith.cast %12 : (si7) -> ui4
%3 = hwarith.cast %13 : (i7) -> si5
%3 = hwarith.cast %13 : (si14) -> i4

Traits: AlwaysSpeculatableImplTrait

Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Operands:

Results:

hwarith.constant (::circt::hwarith::ConstantOp)

Produce a constant value

The constant operation produces a sign-aware constant value.

  %result = hwarith.constant 42 : t1

Traits: AlwaysSpeculatableImplTrait, ConstantLike, FirstAttrDerivedResultType

Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Attributes:

Results:

hwarith.div (::circt::hwarith::DivOp)

Bitwidth-aware integer division.

Syntax:

operation ::= `hwarith.div` $inputs attr-dict `:` functional-type($inputs, $result)

The div operation takes two operands and returns one result. The result type is inferred from the operand types, which may be signed or unsigned scalar integer types of arbitrary bitwidth.

Examples:

%0 = hwarith.div %10, %11 : (ui3, ui4) -> ui3
%1 = hwarith.div %12, %13 : (si3, si3) -> si4
%2 = hwarith.div %14, %15 : (ui3, si4) -> si4
%3 = hwarith.div %16, %17 : (si4, ui6) -> si4

Traits: AlwaysSpeculatableImplTrait

Interfaces: ConditionallySpeculatable, InferTypeOpInterface, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Operands:

Results:

hwarith.icmp (::circt::hwarith::ICmpOp)

Sign- and bitwidth-aware integer comparison.

Syntax:

operation ::= `hwarith.icmp` $predicate $lhs `,` $rhs  attr-dict `:` type($lhs) `,` type($rhs)

The icmp operation compares two integers using a predicate. If the predicate is true, returns 1, otherwise returns 0. This operation always returns a one bit wide result of type ui1. Both operand types may be signed or unsigned scalar integer types of arbitrary bitwidth.

Examples:

%0 = hwarith.icmp lt %10, %11 : ui5, ui6
%1 = hwarith.icmp lt %12, %13 : si3, si4
%2 = hwarith.icmp lt %12, %11 : si3, ui6

Traits: AlwaysSpeculatableImplTrait

Interfaces: ConditionallySpeculatable, InferTypeOpInterface, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Attributes:

Operands:

Results:

hwarith.mul (::circt::hwarith::MulOp)

Bitwidth-aware integer multiplication.

Syntax:

operation ::= `hwarith.mul` $inputs attr-dict `:` functional-type($inputs, $result)

The mul operation takes two operands and returns one result. The result type is inferred from the operand types, which may be signed or unsigned scalar integer types of arbitrary bitwidth.

Examples:

%0 = hwarith.mul %10, %11 : (ui3, ui4) -> ui7
%1 = hwarith.mul %12, %13 : (si3, si3) -> si6
%2 = hwarith.mul %14, %15 : (si3, ui5) -> si8

Traits: AlwaysSpeculatableImplTrait, Commutative

Interfaces: ConditionallySpeculatable, InferTypeOpInterface, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Operands:

Results:

hwarith.sub (::circt::hwarith::SubOp)

Bitwidth-aware integer subtraction.

Syntax:

operation ::= `hwarith.sub` $inputs attr-dict `:` functional-type($inputs, $result)

The sub operation takes two operands and returns one result. The result type is inferred from the operand types, which may be signed or unsigned scalar integer types of arbitrary bitwidth.

Examples:

%0 = hwarith.sub %10, %11 : (ui3, ui4) -> si5
%1 = hwarith.sub %12, %13 : (si3, si3) -> si4
%2 = hwarith.sub %14, %15 : (ui3, si4) -> si5
%3 = hwarith.sub %16, %17 : (si4, ui6) -> si8

Traits: AlwaysSpeculatableImplTrait

Interfaces: ConditionallySpeculatable, InferTypeOpInterface, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Operands:

Results:

Type constraints

an arbitrary precision integer with signedness semantics

'hwarith' Dialect Docs

• HW Arith Dialect Rationale