Re-introduced fallback

Author: zhenrongliew

src/bloqade/qasm2/emit/base.py

@@ -54,12 +54,7 @@ def emit_block(self, frame: EmitQASM2Frame, block: ir.Block) -> ast.Node | None:
         for stmt in block.stmts:
             result = self.frame_eval(frame, stmt)
             if isinstance(result, tuple):
-                if len(result) == 0:
-                    continue
-                keys = getattr(stmt, "_results", None) or getattr(stmt, "results", None)
-                if keys is None:
-                    continue
-                frame.set_values(keys, result)
+                frame.set_values(stmt.results, result)
         return None
 
     A = TypeVar("A")
@@ -84,3 +79,6 @@ def assert_node(
 
     def reset(self):
         pass
+
+    def eval_fallback(self, frame: EmitQASM2Frame, node: ir.Statement):
+        return tuple(None for _ in range(len(node.results)))

src/bloqade/qasm2/emit/gate.py

@@ -87,6 +87,5 @@ def emit_err(self, emit: EmitQASM2Gate, frame: EmitQASM2Frame, stmt):
         raise RuntimeError(f"illegal statement {stmt.name} for QASM2 gate routine")
 
     @interp.impl(func.Return)
-    @interp.impl(func.ConstantNone)
     def ignore(self, emit: EmitQASM2Gate, frame: EmitQASM2Frame, stmt):
         return ()

src/bloqade/stim/emit/stim_str.py

@@ -52,6 +52,9 @@ def reset(self):
         self.io.truncate(0)
         self.io.seek(0)
 
+    def eval_fallback(self, frame: EmitStimFrame, node: ir.Statement) -> tuple:
+        return tuple("" for _ in range(len(node.results)))
+
 
 @func.dialect.register(key="emit.stim")
 class FuncEmit(interp.MethodTable):
@@ -66,14 +69,3 @@ def emit_func(self, emit: EmitStimMain, frame: EmitStimFrame, stmt: func.Functio
                     frame.set_values(stmt_.results, res)
 
         return ()
-
-    @interp.impl(func.ConstantNone)
-    def emit_const_none(
-        self, emit: EmitStimMain, frame: EmitStimFrame, stmt: func.ConstantNone
-    ):
-        frame.set(stmt.result, "")
-        return (frame.get(stmt.result),)
-
-    @interp.impl(func.Return)
-    def emit_return(self, emit: EmitStimMain, frame: EmitStimFrame, stmt: func.Return):
-        return ()

test/qasm2/emit/test_qasm2.py

@@ -1,3 +1,4 @@
+import io
 from pathlib import Path
 from contextlib import redirect_stdout
 
@@ -29,15 +30,10 @@ def main():
     target = qasm2.emit.QASM2(custom_gate=True)
     ast = target.emit(main)
     filename = "t_qasm2.qasm"
-    # Read the filename and store in target
-    with open(Path(__file__).parent.resolve() / filename, "r") as io:
-        target = io.read()
-    # Output into filename in the current directory
-    out_path = Path(__file__).parent.resolve() / filename
-    with open(out_path, "w") as f:
-        with redirect_stdout(f):
-            qasm2.parse.pprint(ast)
-    # Read the filename again and store in generated
-    with open(Path(__file__).parent.resolve() / filename, "r") as io:
-        generated = io.read()
+    with open(Path(__file__).parent.resolve() / filename, "r") as txt:
+        target = txt.read()
+    buf = io.StringIO()
+    with redirect_stdout(buf):
+        qasm2.parse.pprint(ast)
+    generated = buf.getvalue()
     assert generated.strip() == target.strip()