Fix permute issue?

Author: ciaranra

python/quantum-pecos/src/pecos/slr/gen_codes/gen_qasm.py

@@ -125,8 +125,12 @@ def block_op_loop(self, block) -> None:
         if len(block.ops) == 0:
             self.write("")
         else:
-            # Save the current permutation map
-            saved_permutation_map = self.permutation_map.copy()
+            # Check if this block contains a Permute operation
+            # If so, we don't want to restore the permutation map
+            contains_permute = any(type(op).__name__ == "Permute" for op in block.ops if hasattr(op, '__class__'))
+            
+            # Save the current permutation map if needed
+            saved_permutation_map = None if contains_permute else self.permutation_map.copy()
 
             for op in block.ops:
                 # TODO: figure out how to identify Block types without using isinstance
@@ -135,8 +139,9 @@ def block_op_loop(self, block) -> None:
                 else:
                     self.write(self.generate_op(op))
 
-            # Restore the permutation map
-            self.permutation_map = saved_permutation_map
+            # Restore the permutation map if we saved it
+            if saved_permutation_map is not None:
+                self.permutation_map = saved_permutation_map
 
     def generate_op(self, op):
         op_name = type(op).__name__
@@ -145,12 +150,28 @@ def generate_op(self, op):
 
         if op_name == "Barrier":
             stat = True
-            qubits = (
-                ", ".join(str(q) for q in op.qregs)
-                if isinstance(op.qregs, list | tuple | set)
-                else op.qregs
-            )
-
+            # Process barrier operands
+            barrier_parts = []
+            for qreg in op.qregs:
+                if hasattr(qreg, 'sym') and hasattr(qreg, 'elems'):  # It's a register
+                    # Check if we need to apply permutation to any qubit in this register
+                    has_permutation = any(
+                        (qreg.sym, i) in self.permutation_map 
+                        for i in range(len(qreg.elems))
+                    )
+                    if not has_permutation:
+                        # No permutation, use compact register notation
+                        barrier_parts.append(qreg.sym)
+                    else:
+                        # Has permutation, list individual qubits
+                        for qubit in qreg.elems:
+                            barrier_parts.append(self.apply_permutation(qubit))
+                elif hasattr(qreg, 'reg') and hasattr(qreg, 'index'):  # It's a single qubit
+                    barrier_parts.append(self.apply_permutation(qreg))
+                else:
+                    barrier_parts.append(str(qreg))
+            
+            qubits = ", ".join(barrier_parts)
             op_str = f"barrier {qubits};"
         elif op_name == "Comment":
             txt = op.txt.split("\n")
@@ -595,8 +616,10 @@ def qgate_sq_qasm(self, op, repr_str: str | None = None):
 
         for q in op.qargs:
             if type(q).__name__ == "QReg":
-                lines = [f"{repr_str} {qubit};" for qubit in q]
-                str_list.extend(lines)
+                # Apply permutation to each qubit in the register
+                for qubit in q:
+                    q_str = self.apply_permutation(qubit)
+                    str_list.append(f"{repr_str} {q_str};")
 
             elif isinstance(q, tuple):
                 if len(q) != op.qsize:

python/quantum-pecos/src/pecos/slr/slr_converter.py

@@ -33,7 +33,7 @@ def generate(
         add_versions: bool = False,
     ) -> str:
         if target == Language.QASM:
-            generator = QASMGenerator(skip_headers=skip_headers)
+            generator = QASMGenerator(skip_headers=skip_headers, add_versions=add_versions)
         elif target in [Language.QIR, Language.QIRBC]:
             self._check_qir_imported()
             generator = QIRGenerator()

python/tests/pecos/regression/test_qasm/random_cases/test_permute.py

@@ -0,0 +1,67 @@
+# Copyright 2025 The PECOS Developers
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+# the License.You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations under the License.
+
+"""Testing SLR->QASM permute cases."""
+
+from pecos.qeclib import qubit as p
+from pecos.slr import Bit, Block, Comment, CReg, If, Main, Permute, QReg, Qubit, Repeat, SlrConverter
+
+from pecos.qeclib.steane.steane_class import Steane
+
+def test_permute1():
+    prog = Main(
+        a := Steane("a"),
+        b := Steane("b"),
+        meas := CReg("meas", 2),
+        Permute(a.d,
+                b.d),
+        Permute(a.a,
+                b.a),
+        a.mx(meas[0]),
+        b.my(meas[1]),
+    )
+
+    qasm = SlrConverter(prog).qasm()
+
+    print(qasm)
+
+    # Check that permutation was applied correctly
+    assert "ry(-pi/2) b_d[0];" in qasm.lower()
+    assert "measure b_d[0] -> a_raw_meas[0];" in qasm.lower()
+    assert "rx(-pi/2) a_d[0];" in qasm.lower()
+    assert "measure a_d[0] -> b_raw_meas[0];" in qasm.lower()
+
+def test_permute2():
+    def my_permute(a: Steane, b: Steane):
+        block = Block(
+            Permute(a.d,b.d),
+            Permute(a.a, b.a),
+        )
+        return block
+
+    prog = Main(
+        a := Steane("a"),
+        b := Steane("b"),
+        meas := CReg("meas", 2),
+        my_permute(a, b),
+        a.mx(meas[0]),
+        b.my(meas[1]),
+    )
+
+    qasm = SlrConverter(prog).qasm()
+
+    print(qasm)
+
+    # Check that permutation was applied correctly
+    assert "ry(-pi/2) b_d[0];" in qasm.lower()
+    assert "measure b_d[0] -> a_raw_meas[0];" in qasm.lower()
+    assert "rx(-pi/2) a_d[0];" in qasm.lower()
+    assert "measure a_d[0] -> b_raw_meas[0];" in qasm.lower()

python/tests/pecos/regression/test_qasm/random_cases/test_slr_phys.py

@@ -79,7 +79,6 @@ def test_bell():
     qasm = (
         "OPENQASM 2.0;\n"
         'include "hqslib1.inc";\n'
-        f"// Generated using: PECOS version {__version__}\n"
         "qreg q[2];\n"
         "creg m[2];\n"
         "h q[0];\n"
@@ -145,7 +144,6 @@ def __init__(self, q0: Qubit, q1: Qubit, m0: Bit, m1: Bit) -> None:
     qasm = (
         "OPENQASM 2.0;\n"
         'include "hqslib1.inc";\n'
-        f"// Generated using: PECOS version {__version__}\n"
         "qreg q[2];\n"
         "creg m[2];\n"
         "creg c[4];\n"
@@ -178,7 +176,6 @@ def test_strange_program() -> None:
     qasm = (
         "OPENQASM 2.0;\n"
         'include "hqslib1.inc";\n'
-        f"// Generated using: PECOS version {__version__}\n"
         "qreg q[2];\n"
         "creg c[4];\n"
         "creg b[4];\n"
@@ -187,7 +184,7 @@ def test_strange_program() -> None:
         "c = 3;\n"
         "// Here is some injected QASM:\n"
         "c = b & 1;\n"
-        "// Permuting: q[1] -> q[0], q[0] -> q[1]\n"
+        "// Permutation: q[0] -> q[1], q[1] -> q[0]\n"
         "h q[1];"
     )
 
@@ -223,7 +220,7 @@ def test_control_flow_qir():
         ),
         Barrier(q[0], q[1]),
         p.F4dg(q[1]),
-        p.Sdg(q[0]),
+        p.SZdg(q[0]),
         p.CX(q[0], q[1]),
         Barrier(q[1], q[0]),
         p.RX[0.3](q[0]),