passes -> pipelines and documentation.

frontend/catalyst/compilation_pipelines.py

@@ -432,17 +432,20 @@ class QJIT:
             after the Python process ends. If ``False``, these representations
             will instead be stored in a temporary folder, which will be deleted
             as soon as the QJIT instance is deleted.
+        pipelines (Optional(List[AnyType]): A list of pipelines to be executed. The elements of
+            the list are asked to implement a run method which takes the output of the previous run
+            as an input to the next element, and so on.
         compile_options (Optional[CompileOptions]): Common compilation options
     """
 
     # pylint: disable=too-many-arguments
-    def __init__(self, fn, target, keep_intermediate, passes, compile_options=None):
+    def __init__(self, fn, target, keep_intermediate, pipelines, compile_options=None):
         self.qfunc = fn
         self.c_sig = None
         functools.update_wrapper(self, fn)
         self.compile_options = compile_options
         self._compiler = Compiler()
-        self.passes = passes
+        self.pipelines = pipelines
         self._jaxpr = None
         self._mlir = None
         self._llvmir = None
@@ -518,7 +521,7 @@ def compile(self):
         shared_object = self._compiler.run(
             self.mlir_module,
             keep_intermediate=self.keep_intermediate,
-            passes=self.passes,
+            pipelines=self.pipelines,
             options=self.compile_options,
         )
         self._llvmir = self._compiler.get_output_of("LLVMDialectToLLVMIR")
@@ -559,7 +562,13 @@ def __call__(self, *args, **kwargs):
 
 
 def qjit(
-    fn=None, *, target="binary", keep_intermediate=False, verbose=False, logfile=None, passes=None
+    fn=None,
+    *,
+    target="binary",
+    keep_intermediate=False,
+    verbose=False,
+    logfile=None,
+    pipelines=None,
 ):
     """A just-in-time decorator for PennyLane and JAX programs using Catalyst.
 
@@ -582,6 +591,9 @@ def qjit(
         verbosity (int): Verbosity level (0 - disabled, >0 - enabled)
         logfile (Optional[TextIOWrapper]): File object to write verose messages to (default -
             sys.stderr).
+        pipelines (Optional(List[AnyType]): A list of pipelines to be executed. The elements of
+            the list are asked to implement a run method which takes the output of the previous run
+            as an input to the next element, and so on.
 
     Returns:
         QJIT object.
@@ -648,9 +660,9 @@ def circuit(x: complex, z: ShapedArray(shape=(3,), dtype=jnp.float64)):
     """
 
     if fn is not None:
-        return QJIT(fn, target, keep_intermediate, passes, CompileOptions(verbose, logfile))
+        return QJIT(fn, target, keep_intermediate, pipelines, CompileOptions(verbose, logfile))
 
     def wrap_fn(fn):
-        return QJIT(fn, target, keep_intermediate, passes, CompileOptions(verbose, logfile))
+        return QJIT(fn, target, keep_intermediate, pipelines, CompileOptions(verbose, logfile))
 
     return wrap_fn

frontend/catalyst/compiler.py

@@ -407,7 +407,7 @@ def __init__(self):
         # pylint: disable=consider-using-with
         self.workspace = tempfile.TemporaryDirectory()
 
-    def run(self, mlir_module, keep_intermediate=False, passes=None, options=None):
+    def run(self, mlir_module, keep_intermediate=False, pipelines=None, options=None):
         """Compile an MLIR module to a shared object.
 
         .. note::
@@ -417,7 +417,7 @@ def run(self, mlir_module, keep_intermediate=False, passes=None, options=None):
 
         Args:
             mlir_module (Module): the MLIR module
-            passes (List[Any]): the list of compilation passes
+            pipelines (List[Any]): the list of compilation pipelines
 
         Returns:
             Shared object
@@ -436,8 +436,8 @@ def run(self, mlir_module, keep_intermediate=False, passes=None, options=None):
         else:
             workspace_name = self.workspace.name
 
-        if passes is None:
-            passes = [
+        if pipelines is None:
+            pipelines = [
                 MHLOPass,
                 QuantumCompilationPass,
                 BufferizationPass,
@@ -453,41 +453,41 @@ def run(self, mlir_module, keep_intermediate=False, passes=None, options=None):
         with open(filename, "w", encoding="utf-8") as f:
             mlir_module.operation.print(f, print_generic_op_form=False, assume_verified=True)
 
-        for _pass in passes:
-            output = _pass.run(filename, options=options)
-            self.pass_pipeline_output[_pass] = output
+        for pipeline in pipelines:
+            output = pipeline.run(filename, options=options)
+            self.pass_pipeline_output[pipeline] = output
             filename = os.path.abspath(output)
 
         return filename
 
     @staticmethod
-    def _get_class_from_string(_pass):
-        return getattr(sys.modules[__name__], _pass)
+    def _get_class_from_string(pipeline):
+        return getattr(sys.modules[__name__], pipeline)
 
-    def _get_output_file_of(self, _pass):
-        cls = Compiler._get_class_from_string(_pass)
+    def _get_output_file_of(self, pipeline):
+        cls = Compiler._get_class_from_string(pipeline)
         return self.pass_pipeline_output.get(cls)
 
-    def get_output_of(self, _pass):
-        """Get the output IR of a pass.
+    def get_output_of(self, pipeline):
+        """Get the output IR of a pipeline.
         Args:
-            _pass (str): name of pass class
+            pipeline (str): name of pass class
 
         Returns
             (str): output IR
         """
         try:
-            fname = self._get_output_file_of(_pass)
+            fname = self._get_output_file_of(pipeline)
         except AttributeError as e:
-            raise ValueError(f"Output for pass {_pass} not found.") from e
+            raise ValueError(f"Output for pass {pipeline} not found.") from e
         with open(fname, "r", encoding="utf-8") as f:
             txt = f.read()
         return txt
 
-    def print(self, _pass):
+    def print(self, pipeline):
         """Print the output IR of pass.
         Args:
-            _pass (str): name of pass class
+            pipeline (str): name of pass class
         """
-        txt = self.get_output_of(_pass)
+        txt = self.get_output_of(pipeline)
         print(txt)

frontend/test/pytest/test_compiler.py

@@ -81,6 +81,7 @@ def test_no_executable(self):
         """Test that executable was set from a custom PassPipeline."""
 
         class CustomClassWithNoExecutable(PassPipeline):
+            # pylint: disable=missing-class-docstring
             _default_flags = ["some-command-but-it-is-actually-a-flag"]
 
         with pytest.raises(ValueError, match="Executable not specified."):
@@ -165,9 +166,9 @@ def workflow():
 
         mlir_module, _, _ = get_mlir(workflow)
         # This means that we are not running any pass.
-        passes = []
+        pipelines = []
         identity_compiler = Compiler()
-        identity_compiler.run(mlir_module, keep_intermediate=True, passes=passes)
+        identity_compiler.run(mlir_module, keep_intermediate=True, pipelines=pipelines)
         directory = os.path.join(os.getcwd(), workflow.__name__)
         assert os.path.exists(directory)
         files = os.listdir(directory)
@@ -185,9 +186,9 @@ def workflow():
 
         mlir_module, _, _ = get_mlir(workflow)
         # This means that we are not running any pass.
-        passes = []
+        pipelines = []
         identity_compiler = Compiler()
-        identity_compiler.run(mlir_module, passes=passes)
+        identity_compiler.run(mlir_module, pipelines=pipelines)
         files = os.listdir(identity_compiler.workspace.name)
         # The directory is non-empty. Should at least contain the original .mlir file
         assert files