Fix compiler pushing /measurement/ pulses to later time

src/qibolab/compilers/compiler.py

@@ -104,7 +104,6 @@ def _compile_gate(
         platform,
         sequence,
         virtual_z_phases,
-        moment_start,
         delays,
         wire_names,
     ):
@@ -120,13 +119,12 @@ def _compile_gate(
 
         # update global pulse sequence
         # determine the right start time based on the availability of the qubits involved
-        all_qubits = {*gate_sequence.qubits, *gate.qubits}
+        all_qubits = {*gate_sequence.qubits, *gate.qubits, *gate_phases.keys()}
         start = max(
-            *[
+            [
                 sequence.get_qubit_pulses(qubit).finish + delays[qubit]
                 for qubit in all_qubits
-            ],
-            moment_start,
+            ]
         )
         # shift start time and phase according to the global sequence
         for pulse in gate_sequence:
@@ -159,7 +157,6 @@ def compile(self, circuit, platform):
         # process circuit gates
         delays = defaultdict(int)
         for moment in circuit.queue.moments:
-            moment_start = sequence.finish
             for gate in set(filter(lambda x: x is not None, moment)):
                 if isinstance(gate, gates.Align):
                     for qubit in gate.qubits:
@@ -170,7 +167,6 @@ def compile(self, circuit, platform):
                     platform,
                     sequence,
                     virtual_z_phases,
-                    moment_start,
                     delays,
                     circuit.wire_names,
                 )

tests/test_compiler.py

@@ -0,0 +1,64 @@
+import numpy as np
+import pytest
+from qibo import Circuit, gates
+
+from qibolab import create_platform
+from qibolab.compilers.compiler import Compiler
+
+
+@pytest.fixture
+def dummy():
+    return create_platform("dummy")
+
+
+@pytest.fixture
+def dummy_couplers():
+    return create_platform("dummy_couplers")
+
+
+@pytest.fixture
+def compiler():
+    return Compiler.default()
+
+
+def test_measurement_timings(dummy, compiler):
+    q0, q1 = 0, 1
+    circ = Circuit(2)
+    circ.add(gates.GPI2(q0, phi=0.0))
+    circ.add(gates.GPI2(q1, phi=np.pi / 2))
+    circ.add(gates.GPI2(q1, phi=np.pi))
+
+    # put measurement in different moments
+    circ.add(gates.M(q0))
+    circ.add(gates.M(q1))
+
+    # make sure they are in different moments before proceeding
+    assert not any(
+        [
+            len([gate for gate in m if isinstance(gate, gates.M)]) == 2
+            for m in circ.queue.moments
+        ]
+    )
+
+    circ._wire_names = [q0, q1]
+    sequence, _ = compiler.compile(circ, dummy)
+
+    MEASUREMENT_DURATION = 2000
+    for pulse in sequence.ro_pulses:
+        # assert that measurements don't happen one after another
+        assert not pulse.start >= MEASUREMENT_DURATION
+
+
+def test_coupler_pulse_timing(dummy_couplers, compiler):
+    q0, q1, q2 = 0, 1, 2
+    circ = Circuit(3)
+    circ.add(gates.GPI2(q0, phi=0.0))
+    circ.add(gates.GPI2(q0, phi=np.pi))
+    circ.add(gates.GPI2(q1, phi=0.0))
+    circ.add(gates.CZ(q1, q2))
+
+    circ._wire_names = [q0, q1, q2]
+    sequence, _ = compiler.compile(circ, dummy_couplers)
+
+    coupler_pulse = sequence.cf_pulses[0]
+    assert coupler_pulse.start == 40