Add type check to Measure stmt and test

Author: david-pl

src/bloqade/qasm2/dialects/core/stmts.py

@@ -51,6 +51,17 @@ class Measure(ir.Statement):
     carg: ir.SSAValue = info.argument(BitType | CRegType)
     """carg (Bit): The bit to store the result in."""
 
+    def check_type(self) -> None:
+        qarg_is_qubit = self.qarg.type.is_subseteq(QubitType)
+        carg_is_bit = self.carg.type.is_subseteq(BitType)
+        if (qarg_is_qubit and not carg_is_bit) or (not qarg_is_qubit and carg_is_bit):
+            raise ir.TypeCheckError(
+                self,
+                "Can't perform measurement with single (qu)bit and an entire register!",
+                help="Instead of `measure(qreg[i], creg)` or `measure(qreg, creg[i])`"
+                "use `measure(qreg[i], creg[j])` or `measure(qreg, creg)`, respectively.",
+            )
+
 
 @statement(dialect=dialect)
 class CRegEq(ir.Statement):

test/pyqrack/test_target.py

@@ -1,5 +1,8 @@
 import math
 
+import pytest
+from kirin import ir
+
 from bloqade import qasm2
 from bloqade.pyqrack import PyQrack, reg
 
@@ -137,3 +140,15 @@ def measure_single_qubits():
     result_reg = target.run(measure_register)
 
     assert result_single == result_reg == [reg.Measurement.One, reg.Measurement.One]
+
+    @qasm2.main
+    def measurement_that_errors():
+        q = qasm2.qreg(1)
+        c = qasm2.creg(1)
+        qasm2.measure(q[0], c)
+
+    with pytest.raises(ir.TypeCheckError):
+        measurement_that_errors.code.verify_type()
+
+    with pytest.raises(RuntimeError):
+        target.run(measurement_that_errors)