microquantum.ir.passes¶

IR transformation passes.

Provides the IRPass / IRPassManager abstraction and a small initial set of correct structural transformations:

RemoveIdentityGates — drops gates that are structurally identity (identity gates, zero-angle rotations, empty conditional blocks).
CancelAdjacentInverse — cancels adjacent U, U-dagger pairs on the same qubits (self-inverse gates, known inverse pairs, opposite rotations).
CombineRotations — merges adjacent same-axis rotation gates on one qubit into a single rotation (R(a) R(b) -> R(a + b)).
BindParameters — substitutes symbolic parameters with numeric values, producing an executable (bound) IR.
GateDecomposition — expands a gate into a supported basis gate set (exact, standard identities only).

All passes are NumPy-free and produce new IRCircuit objects, leaving the input untouched.

Module Contents¶

class microquantum.ir.passes.IRPass[source]¶

Bases: abc.ABC

Abstract base class for IR transformation passes.

A pass inspects and transforms an IRCircuit into a new IRCircuit. Passes never mutate their input.

property name: str[source]¶

Abstractmethod:
Return type:: str

Human-readable pass name.

abstractmethod run(ir)[source]¶

Return the transformed IR circuit.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit)
Return type:: microquantum.ir.circuit_ir.IRCircuit

class microquantum.ir.passes.IRPassManager(passes=None)[source]¶

Runs an ordered pipeline of IR passes.

Example:

pm = IRPassManager([RemoveIdentityGates(), CancelAdjacentInverse()])
optimized = pm.run(ir)

Parameters:: passes (Optional[list[IRPass]])

property passes: list[IRPass][source]¶

The registered passes.

Return type:: list[IRPass]

append_pass(pass_)[source]¶

Append a single pass and return self.

Parameters:: pass_ (IRPass)
Return type:: IRPassManager

run(ir)[source]¶

Run all passes sequentially, feeding each output into the next.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit) – The input IR circuit.
Returns:: The IR after all passes have been applied.
Return type:: microquantum.ir.circuit_ir.IRCircuit

class microquantum.ir.passes.RemoveIdentityGates[source]¶

Bases: IRPass

Remove structurally-identity operations.

Drops id gates, zero-angle rotation gates, and empty conditional blocks (recursively).

property name: str[source]¶

Human-readable pass name.

Return type:: str

run(ir)[source]¶

Return the transformed IR circuit.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit)
Return type:: microquantum.ir.circuit_ir.IRCircuit

class microquantum.ir.passes.CancelAdjacentInverse[source]¶

Bases: IRPass

Cancel adjacent inverse gate pairs on the same qubits.

Recognizes self-inverse gates (H, X, Y, Z, CNOT, CZ, SWAP), the standard inverse pairs (S/Sdg, T/Tdg) and opposite rotations (R(a) R(-a)). Barriers and non-gate nodes act as separators.

property name: str[source]¶

Human-readable pass name.

Return type:: str

run(ir)[source]¶

Return the transformed IR circuit.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit)
Return type:: microquantum.ir.circuit_ir.IRCircuit

class microquantum.ir.passes.CombineRotations[source]¶

Bases: IRPass

Fuse adjacent same-axis rotations on one qubit: R(a) R(b) -> R(a+b).

property name: str[source]¶

Human-readable pass name.

Return type:: str

run(ir)[source]¶

Return the transformed IR circuit.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit)
Return type:: microquantum.ir.circuit_ir.IRCircuit

class microquantum.ir.passes.BindParameters(param_map)[source]¶

Bases: IRPass

Bind symbolic parameters to numeric values.

Parameters:: param_map (Mapping[Union[str, microquantum.core.parameter.Parameter], float]) – Mapping from Parameter (or parameter name) to a numeric value. Parameters absent from the mapping remain symbolic in the output IR.

property name: str[source]¶

Human-readable pass name.

Return type:: str

run(ir)[source]¶

Return the transformed IR circuit.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit)
Return type:: microquantum.ir.circuit_ir.IRCircuit

class microquantum.ir.passes.GateDecomposition(basis_gates)[source]¶

Bases: IRPass

Expand gates not in the target basis.

Only standard, exact identities are used:

cz(c, t) -> h(t), cnot(c, t), h(t) (basis has h and cnot)
swap(a, b) -> cnot(a,b), cnot(b,a), cnot(a,b) (basis has cnot)

Gates that cannot be decomposed are left in place; use the compiler’s diagnostics to detect them.

The basis is normalized to MicroQuantum IR gate names, so a Target spelling the controlled-NOT as "cx" is equivalent to the IR’s "cnot".

Parameters:: basis_gates (Union[microquantum.core.device.Target, Iterable[str]]) – The supported gate-name set (e.g. a Target’s native_gates).

property name: str[source]¶

Human-readable pass name.

Return type:: str

run(ir)[source]¶

Return the transformed IR circuit.

Parameters:: ir (microquantum.ir.circuit_ir.IRCircuit)
Return type:: microquantum.ir.circuit_ir.IRCircuit

to_dict()[source]¶

Pass configuration for diagnostics.

Return type:: dict[str, Any]

microquantum.ir.passes.optimize(ir, level=1)[source]¶

Run the standard optimization pipeline on ir.

Parameters:

ir (microquantum.ir.circuit_ir.IRCircuit) – The IR circuit to optimize.
level (int) – 0 = returns input unchanged, 1 = identity removal + inverse cancellation, 2 = additionally fuses same-axis rotations.

Returns:

The optimized IR circuit.

Return type:

microquantum.ir.circuit_ir.IRCircuit