Test stats collection

proto/swift_proto_library.bzl

@@ -74,12 +74,18 @@ def _swift_proto_library_impl(ctx):
     direct_swift_proto_cc_info = direct_providers.direct_swift_proto_cc_info
     direct_swift_info = direct_providers.direct_swift_info
     direct_swift_proto_info = direct_providers.direct_swift_proto_info
+    direct_stats_files = getattr(
+        direct_output_group_info,
+        "swift_stats",
+        depset(),
+    ).to_list()
     direct_files = compact(
         [module.swift.swiftdoc for module in direct_swift_info.direct_modules] +
         [module.swift.swiftinterface for module in direct_swift_info.direct_modules] +
         [module.swift.private_swiftinterface for module in direct_swift_info.direct_modules] +
         [module.swift.swiftmodule for module in direct_swift_info.direct_modules] +
-        [module.swift.swiftsourceinfo for module in direct_swift_info.direct_modules],
+        [module.swift.swiftsourceinfo for module in direct_swift_info.direct_modules] +
+        direct_stats_files,
     )
 
     return [

proto/swift_proto_library_group.bzl

@@ -104,12 +104,18 @@ def _swift_proto_library_group_impl(ctx):
     direct_swift_proto_cc_info = proto_target[SwiftProtoCcInfo]
     direct_swift_info = proto_target[SwiftInfo]
     direct_swift_proto_info = proto_target[SwiftProtoInfo]
+    direct_stats_files = getattr(
+        direct_output_group_info,
+        "swift_stats",
+        depset(),
+    ).to_list()
     direct_files = compact(
         [module.swift.swiftdoc for module in direct_swift_info.direct_modules] +
         [module.swift.swiftinterface for module in direct_swift_info.direct_modules] +
         [module.swift.private_swiftinterface for module in direct_swift_info.direct_modules] +
         [module.swift.swiftmodule for module in direct_swift_info.direct_modules] +
-        [module.swift.swiftsourceinfo for module in direct_swift_info.direct_modules],
+        [module.swift.swiftsourceinfo for module in direct_swift_info.direct_modules] +
+        direct_stats_files,
     )
 
     return [

swift/internal/compiling.bzl

@@ -42,6 +42,7 @@ load(
     "SWIFT_FEATURE_EMIT_BC",
     "SWIFT_FEATURE_EMIT_C_MODULE",
     "SWIFT_FEATURE_EMIT_PRIVATE_SWIFTINTERFACE",
+    "SWIFT_FEATURE_EMIT_STATS",
     "SWIFT_FEATURE_EMIT_SWIFTDOC",
     "SWIFT_FEATURE_EMIT_SWIFTINTERFACE",
     "SWIFT_FEATURE_ENABLE_EMBEDDED",
@@ -567,6 +568,9 @@ def compile(
                 represents the location where macro expansion files were written
                 (only in debug/fastbuild and only when the toolchain supports
                 macros).
+
+            *   `stats_directory`: A directory-type `File` that represents the
+                location where Swift compilation statistics were written.
     """
     toolchains = gather_toolchains(
         swift_toolchain = swift_toolchain,
@@ -658,6 +662,7 @@ def compile(
     if split_derived_file_generation:
         all_compile_outputs = compact([
             compile_outputs.indexstore_directory,
+            compile_outputs.stats_directory,
         ]) + compile_outputs.object_files + compile_outputs.const_values_files
         all_derived_outputs = compact([
             # The `.swiftmodule` file is explicitly listed as the first output
@@ -686,6 +691,7 @@ def compile(
             compile_outputs.generated_header_file,
             compile_outputs.indexstore_directory,
             compile_outputs.macro_expansion_directory,
+            compile_outputs.stats_directory,
         ]) + compile_outputs.object_files + compile_outputs.const_values_files
         all_derived_outputs = []
 
@@ -960,6 +966,7 @@ to use swift_common.compile(include_dev_srch_paths = ...) instead.\
             const_values_files = compile_outputs.const_values_files,
             indexstore_directory = compile_outputs.indexstore_directory,
             macro_expansion_directory = compile_outputs.macro_expansion_directory,
+            stats_directory = compile_outputs.stats_directory,
         ),
         swift_info = SwiftInfo(
             modules = [module_context],
@@ -1523,6 +1530,16 @@ def _declare_compile_outputs(
         indexstore_directory = None
         include_index_unit_paths = False
 
+    if is_feature_enabled(
+        feature_configuration = feature_configuration,
+        feature_name = SWIFT_FEATURE_EMIT_STATS,
+    ):
+        stats_directory = actions.declare_directory(
+            "{}.swift-stats".format(target_name),
+        )
+    else:
+        stats_directory = None
+
     if not output_nature.emits_multiple_objects:
         # If we're emitting a single object, we don't use an object map; we just
         # declare the output file that the compiler will generate and there are
@@ -1607,6 +1624,7 @@ def _declare_compile_outputs(
         object_files = object_files,
         output_file_map = output_file_map,
         derived_files_output_file_map = derived_files_output_file_map,
+        stats_directory = stats_directory,
         swiftdoc_file = swiftdoc_file,
         swiftinterface_file = swiftinterface_file,
         swiftmodule_file = swiftmodule_file,

swift/internal/feature_names.bzl

@@ -415,6 +415,10 @@ SWIFT_FEATURE_SUPPRESS_WARNINGS = "swift.suppress_warnings"
 # Pass -warnings-as-errors to the compiler.
 SWIFT_FEATURE_TREAT_WARNINGS_AS_ERRORS = "swift.treat_warnings_as_errors"
 
+# If enabled, Swift compilation actions emit unified compilation statistics into
+# a declared output directory.
+SWIFT_FEATURE_EMIT_STATS = "swift.emit_stats"
+
 # A feature that adds target_name in output path to support building
 # multiple frameworks with different target name, but same module name.
 SWIFT_FEATURE_ADD_TARGET_NAME_TO_OUTPUT = "swift.add_target_name_to_output"

swift/internal/output_groups.bzl

@@ -39,6 +39,7 @@ def supplemental_compilation_output_groups(
     const_values_files = []
     indexstore_files = list(additional_indexstore_files)
     macro_expansions_files = []
+    stats_files = []
 
     for outputs in supplemental_outputs:
         if outputs.ast_files:
@@ -49,6 +50,9 @@ def supplemental_compilation_output_groups(
             indexstore_files.append(outputs.indexstore_directory)
         if outputs.macro_expansion_directory:
             macro_expansions_files.append(outputs.macro_expansion_directory)
+        stats_directory = getattr(outputs, "stats_directory", None)
+        if stats_directory:
+            stats_files.append(stats_directory)
 
     output_groups = {}
     if ast_files:
@@ -59,4 +63,6 @@ def supplemental_compilation_output_groups(
         output_groups["swift_index_store"] = depset(indexstore_files)
     if macro_expansions_files:
         output_groups["macro_expansions"] = depset(macro_expansions_files)
+    if stats_files:
+        output_groups["swift_stats"] = depset(stats_files)
     return output_groups

swift/swift_binary.bzl

@@ -43,6 +43,7 @@ load(
 )
 load(
     "//swift/internal:utils.bzl",
+    "compact",
     "expand_locations",
     "get_providers",
     "include_developer_search_paths",
@@ -88,6 +89,7 @@ def _swift_binary_impl(ctx):
     output_groups = {}
     module_contexts = []
     additional_linking_contexts = []
+    default_compile_outputs = []
 
     # If the binary has sources, compile those first and collect the outputs to
     # be passed to the linker.
@@ -134,6 +136,9 @@ def _swift_binary_impl(ctx):
         output_groups = supplemental_compilation_output_groups(
             supplemental_outputs,
         )
+        default_compile_outputs = compact([
+            supplemental_outputs.stats_directory,
+        ])
     else:
         compile_result = None
         entry_point_function_name = None
@@ -196,7 +201,9 @@ def _swift_binary_impl(ctx):
         DefaultInfo(
             executable = linking_outputs.executable,
             files = depset(
-                [linking_outputs.executable] + additional_debug_outputs,
+                [linking_outputs.executable] +
+                additional_debug_outputs +
+                default_compile_outputs,
             ),
             runfiles = ctx.runfiles(
                 collect_data = True,

swift/swift_compiler_plugin.bzl

@@ -49,6 +49,7 @@ load(
 )
 load(
     "//swift/internal:utils.bzl",
+    "compact",
     "expand_locations",
     "get_providers",
 )
@@ -112,6 +113,9 @@ def _swift_compiler_plugin_impl(ctx):
     module_contexts.append(module_context)
     compilation_outputs = compile_result.compilation_outputs
     supplemental_outputs = compile_result.supplemental_outputs
+    default_compile_outputs = compact([
+        supplemental_outputs.stats_directory,
+    ])
 
     # Apply the optional debugging outputs extension if the toolchain defines
     # one.
@@ -189,7 +193,9 @@ def _swift_compiler_plugin_impl(ctx):
         DefaultInfo(
             executable = binary_linking_outputs.executable,
             files = depset(
-                [binary_linking_outputs.executable] + additional_debug_outputs,
+                [binary_linking_outputs.executable] +
+                additional_debug_outputs +
+                default_compile_outputs,
             ),
             runfiles = ctx.runfiles(
                 collect_data = True,

swift/swift_library.bzl

@@ -256,6 +256,7 @@ def _swift_library_impl(ctx):
         module_context.swift.private_swiftinterface,
         module_context.swift.swiftmodule,
         module_context.swift.swiftsourceinfo,
+        supplemental_outputs.stats_directory,
         linking_output.library_to_link.static_library,
         linking_output.library_to_link.pic_static_library,
     ])

swift/swift_test.bzl

@@ -50,6 +50,7 @@ load(
 )
 load(
     "//swift/internal:utils.bzl",
+    "compact",
     "expand_locations",
     "get_providers",
     "include_developer_search_paths",
@@ -496,12 +497,18 @@ def _swift_test_impl(ctx):
         {"TEST_BINARIES_FOR_LLVM_COV": linking_outputs.executable.short_path},
         expanded_env.get_expanded_env(ctx, {}),
     )
+    default_compile_outputs = compact([
+        getattr(outputs, "stats_directory", None)
+        for outputs in all_supplemental_outputs
+    ])
 
     return [
         DefaultInfo(
             executable = linking_outputs.executable,
             files = depset(
-                [linking_outputs.executable] + additional_debug_outputs,
+                [linking_outputs.executable] +
+                additional_debug_outputs +
+                default_compile_outputs,
             ),
             runfiles = ctx.runfiles(
                 collect_data = True,

swift/toolchains/config/compile_config.bzl

@@ -51,6 +51,7 @@ load(
     "SWIFT_FEATURE_EMIT_BC",
     "SWIFT_FEATURE_EMIT_C_MODULE",
     "SWIFT_FEATURE_EMIT_PRIVATE_SWIFTINTERFACE",
+    "SWIFT_FEATURE_EMIT_STATS",
     "SWIFT_FEATURE_EMIT_SWIFTDOC",
     "SWIFT_FEATURE_EMIT_SWIFTINTERFACE",
     "SWIFT_FEATURE_ENABLE_BARE_SLASH_REGEX",
@@ -283,6 +284,13 @@ def compile_action_configs(
             configurators = [_constant_value_extraction_configurator],
         ),
 
+        # Configure compiler statistics output.
+        ActionConfigInfo(
+            actions = [SWIFT_ACTION_COMPILE],
+            configurators = [_stats_output_configurator],
+            features = [SWIFT_FEATURE_EMIT_STATS],
+        ),
+
         # Link Time Optimization (LTO).
         ActionConfigInfo(
             actions = all_compile_action_names(),
@@ -2398,6 +2406,14 @@ def _constant_value_extraction_configurator(prerequisites, args):
         inputs = [prerequisites.const_gather_protocols_file],
     )
 
+def _stats_output_configurator(prerequisites, args):
+    """Adds flags related to Swift compile statistics output."""
+    args.add(
+        "-Xwrapped-swift=-stats-output-dir={}".format(
+            prerequisites.stats_directory.path,
+        ),
+    )
+
 def _upcoming_and_experimental_features_configurator(prerequisites, args):
     """Adds upcoming and experimental features to the command line."""
     args.add_all(

test/BUILD

@@ -25,6 +25,7 @@ load(":private_deps_tests.bzl", "private_deps_test_suite")
 load(":private_swiftinterface_tests.bzl", "private_swiftinterface_test_suite")
 load(":runtime_deps_tests.bzl", "runtime_deps_test_suite")
 load(":split_derived_files_tests.bzl", "split_derived_files_test_suite")
+load(":stats_output_tests.bzl", "stats_output_test_suite")
 load(":swift_binary_linking_tests.bzl", "swift_binary_linking_test_suite")
 load(":swift_through_non_swift_tests.bzl", "swift_through_non_swift_test_suite")
 load(":swift_toolchain_tests.bzl", "swift_toolchain_test_suite")
@@ -75,6 +76,8 @@ private_deps_test_suite(name = "private_deps")
 
 split_derived_files_test_suite(name = "split_derived_files")
 
+stats_output_test_suite(name = "stats_output")
+
 swift_binary_linking_test_suite(name = "swift_binary_rules")
 
 swift_through_non_swift_test_suite(name = "swift_through_non_swift")

test/stats_output_tests.bzl

@@ -0,0 +1,87 @@
+"""Tests for `swift.emit_stats`."""
+
+load(
+    "//test/rules:action_command_line_test.bzl",
+    "action_command_line_test",
+    "make_action_command_line_test_rule",
+)
+load(
+    "//test/rules:provider_test.bzl",
+    "make_provider_test_rule",
+)
+
+stats_output_command_line_test = make_action_command_line_test_rule(
+    config_settings = {
+        "//command_line_option:features": [
+            "swift.emit_stats",
+        ],
+    },
+)
+
+stats_output_provider_test = make_provider_test_rule(
+    config_settings = {
+        "//command_line_option:features": [
+            "swift.emit_stats",
+        ],
+    },
+)
+
+def stats_output_test_suite(name, tags = []):
+    """Test suite for Swift stats output.
+
+    Args:
+        name: The base name to be used in targets created by this macro.
+        tags: Additional tags to apply to each test.
+    """
+    all_tags = [name] + tags
+
+    action_command_line_test(
+        name = "{}_disabled_by_default".format(name),
+        mnemonic = "SwiftCompile",
+        not_expected_argv = [
+            "-stats-output-dir",
+        ],
+        tags = all_tags,
+        target_under_test = "//test/fixtures/debug_settings:simple",
+    )
+
+    stats_output_command_line_test(
+        name = "{}_command_line".format(name),
+        expected_argv = [
+            "-Xwrapped-swift=-stats-output-dir=$(BIN_DIR)/test/fixtures/debug_settings/simple.swift-stats",
+        ],
+        mnemonic = "SwiftCompile",
+        not_expected_argv = [
+            "-trace-stats-events",
+        ],
+        tags = all_tags,
+        target_under_test = "//test/fixtures/debug_settings:simple",
+    )
+
+    stats_output_provider_test(
+        name = "{}_default_files".format(name),
+        expected_files = [
+            "test/fixtures/debug_settings/simple.swift-stats",
+            "*",
+        ],
+        field = "files",
+        provider = "DefaultInfo",
+        tags = all_tags,
+        target_under_test = "//test/fixtures/debug_settings:simple",
+    )
+
+    stats_output_provider_test(
+        name = "{}_output_group".format(name),
+        expected_files = [
+            "test/fixtures/debug_settings/simple.swift-stats",
+        ],
+        field = "swift_stats",
+        provider = "OutputGroupInfo",
+        tags = all_tags,
+        target_under_test = "//test/fixtures/debug_settings:simple",
+    )
+
+    native.test_suite(
+        name = name,
+        tags = all_tags,
+    )