Bug 1872666 - Remove OrderedDict code from YAML file loading. r=iain,profiler-reviewers,canaltinova

`mach` requires Python 3.7+ since bug 1734402, and Python 3.7 made preserving
dictionary insertion order an official part of the language.

Also use `safe_load` instead of `load` because it doesn't require a loader argument
and is safer (although it doesn't really matter for this use case).

Differential Revision: https://phabricator.services.mozilla.com/D197497

js/src/jit/GenerateABIFunctionType.py

@@ -1,5 +1,3 @@
-from collections import OrderedDict
-
 import buildconfig
 import six
 import yaml
@@ -40,20 +38,7 @@ def load_yaml(yaml_path):
     pp.do_filter("substitution")
     pp.do_include(yaml_path)
     contents = pp.out.getvalue()
-
-    # Load into an OrderedDict to ensure order is preserved. Note: Python 3.7+
-    # also preserves ordering for normal dictionaries.
-    # Code based on https://stackoverflow.com/a/21912744.
-    class OrderedLoader(yaml.Loader):
-        pass
-
-    def construct_mapping(loader, node):
-        loader.flatten_mapping(node)
-        return OrderedDict(loader.construct_pairs(node))
-
-    tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
-    OrderedLoader.add_constructor(tag, construct_mapping)
-    return yaml.load(contents, OrderedLoader)
+    return yaml.safe_load(contents)
 
 
 def cpp_arg_type(arg_type):

js/src/jit/GenerateCacheIRFiles.py

@@ -4,8 +4,6 @@
 
 # This script generates jit/CacheIROpsGenerated.h from CacheIROps.yaml
 
-from collections import OrderedDict
-
 import buildconfig
 import six
 import yaml
@@ -46,20 +44,7 @@ def load_yaml(yaml_path):
     pp.do_filter("substitution")
     pp.do_include(yaml_path)
     contents = pp.out.getvalue()
-
-    # Load into an OrderedDict to ensure order is preserved. Note: Python 3.7+
-    # also preserves ordering for normal dictionaries.
-    # Code based on https://stackoverflow.com/a/21912744.
-    class OrderedLoader(yaml.Loader):
-        pass
-
-    def construct_mapping(loader, node):
-        loader.flatten_mapping(node)
-        return OrderedDict(loader.construct_pairs(node))
-
-    tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
-    OrderedLoader.add_constructor(tag, construct_mapping)
-    return yaml.load(contents, OrderedLoader)
+    return yaml.safe_load(contents)
 
 
 # Information for generating CacheIRWriter code for a single argument. Tuple
@@ -476,7 +461,7 @@ def generate_cacheirops_header(c_out, yaml_path):
         name = op["name"]
 
         args = op["args"]
-        assert args is None or isinstance(args, OrderedDict)
+        assert args is None or isinstance(args, dict)
 
         shared = op["shared"]
         assert isinstance(shared, bool)

js/src/jit/GenerateLIRFiles.py

@@ -5,8 +5,6 @@
 # This script generates jit/LIROpsGenerated.h (list of LIR instructions)
 # from LIROps.yaml.
 
-from collections import OrderedDict
-
 import buildconfig
 import six
 import yaml
@@ -37,20 +35,7 @@ def load_yaml(yaml_path):
     pp.do_filter("substitution")
     pp.do_include(yaml_path)
     contents = pp.out.getvalue()
-
-    # Load into an OrderedDict to ensure order is preserved. Note: Python 3.7
-    # also preserves ordering for normal dictionaries.
-    # Code based on https://stackoverflow.com/a/21912744.
-    class OrderedLoader(yaml.Loader):
-        pass
-
-    def construct_mapping(loader, node):
-        loader.flatten_mapping(node)
-        return OrderedDict(loader.construct_pairs(node))
-
-    tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
-    OrderedLoader.add_constructor(tag, construct_mapping)
-    return yaml.load(contents, OrderedLoader)
+    return yaml.safe_load(contents)
 
 
 def generate_header(c_out, includeguard, contents):
@@ -256,10 +241,10 @@ def generate_lir_header(c_out, yaml_path):
                 assert result_types[result_type]
 
             operands = op.get("operands", None)
-            assert operands is None or OrderedDict
+            assert operands is None or isinstance(operands, dict)
 
             arguments = op.get("arguments", None)
-            assert arguments is None or isinstance(arguments, OrderedDict)
+            assert arguments is None or isinstance(arguments, dict)
 
             num_temps = op.get("num_temps", 0)
             assert num_temps is None or int

js/src/jit/GenerateMIRFiles.py

@@ -5,8 +5,6 @@
 # This script generates jit/MIROpsGenerated.h (list of MIR instructions)
 # from MIROps.yaml, as well as MIR op definitions.
 
-from collections import OrderedDict
-
 import buildconfig
 import six
 import yaml
@@ -47,20 +45,7 @@ def load_yaml(yaml_path):
     pp.do_filter("substitution")
     pp.do_include(yaml_path)
     contents = pp.out.getvalue()
-
-    # Load into an OrderedDict to ensure order is preserved. Note: Python 3.7+
-    # also preserves ordering for normal dictionaries.
-    # Code based on https://stackoverflow.com/a/21912744.
-    class OrderedLoader(yaml.Loader):
-        pass
-
-    def construct_mapping(loader, node):
-        loader.flatten_mapping(node)
-        return OrderedDict(loader.construct_pairs(node))
-
-    tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
-    OrderedLoader.add_constructor(tag, construct_mapping)
-    return yaml.load(contents, OrderedLoader)
+    return yaml.safe_load(contents)
 
 
 type_policies = {
@@ -322,10 +307,10 @@ def generate_mir_header(c_out, yaml_path):
 
         if gen_boilerplate:
             operands = op.get("operands", None)
-            assert operands is None or isinstance(operands, OrderedDict)
+            assert operands is None or isinstance(operands, dict)
 
             arguments = op.get("arguments", None)
-            assert arguments is None or isinstance(arguments, OrderedDict)
+            assert arguments is None or isinstance(arguments, dict)
 
             no_type_policy = op.get("type_policy", None)
             assert no_type_policy in (None, "none")

js/src/wasm/GenerateBuiltinModules.py

@@ -1,5 +1,3 @@
-from collections import OrderedDict
-
 import buildconfig
 import six
 import yaml
@@ -40,20 +38,7 @@ def load_yaml(yaml_path):
     pp.do_filter("substitution")
     pp.do_include(yaml_path)
     contents = pp.out.getvalue()
-
-    # Load into an OrderedDict to ensure order is preserved. Note: Python 3.7+
-    # also preserves ordering for normal dictionaries.
-    # Code based on https://stackoverflow.com/a/21912744.
-    class OrderedLoader(yaml.Loader):
-        pass
-
-    def construct_mapping(loader, node):
-        loader.flatten_mapping(node)
-        return OrderedDict(loader.construct_pairs(node))
-
-    tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
-    OrderedLoader.add_constructor(tag, construct_mapping)
-    return yaml.load(contents, OrderedLoader)
+    return yaml.safe_load(contents)
 
 
 def cppBool(v):

mozglue/baseprofiler/build/generate_profiling_categories.py

@@ -5,8 +5,6 @@
 # This script generates ProfilingCategoryList.h and profiling_categories.rs
 # files from profiling_categories.yaml.
 
-from collections import OrderedDict
-
 import yaml
 
 CPP_HEADER_TEMPLATE = """\
@@ -104,21 +102,8 @@ def generate_rust_file(c_out, contents):
 
 
 def load_yaml(yaml_path):
-    # Load into an OrderedDict to ensure order is preserved. Note: Python 3.7+
-    # also preserves ordering for normal dictionaries.
-    # Code based on https://stackoverflow.com/a/21912744.
-    class OrderedLoader(yaml.Loader):
-        pass
-
-    def construct_mapping(loader, node):
-        loader.flatten_mapping(node)
-        return OrderedDict(loader.construct_pairs(node))
-
-    tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
-    OrderedLoader.add_constructor(tag, construct_mapping)
-
     file_handler = open(yaml_path)
-    return yaml.load(file_handler, OrderedLoader)
+    return yaml.safe_load(file_handler)
 
 
 def generate_category_macro(name, label, color, subcategories):