Enable profiling for GwtIncompatibleStripper and improve profiling output.

This change extends the profiling support to the GwtIncompatibleStripper by using the shared `compiler_java_binary` macro. The profiling logic in `j2cl_common.bzl` is refactored to be reusable and now includes the action mnemonic in the profile output filename for better clarity.

Additionally we now print the matched targets and corresponding pprof commands for convenience.

PiperOrigin-RevId: 887081179

Author: gkdn

BUILD

@@ -97,7 +97,8 @@ bool_flag(
 # Flag to enable profiling for particular targets.
 # Example usage:
 #   blaze build <my_binary> --//:profiling_filter=<target_pattern>
-#   pprof --flame blaze-bin/<target>.profile
+#   pprof --flame blaze-bin/<target>_<mnemonic>.profile
+# You should also see the matched targets & corresponding pprof command in the blaze output.
 string_flag(
     name = "profiling_filter",
     build_setting_default = "<disabled>",

build_defs/internal_do_not_use/j2cl_common.bzl

@@ -266,13 +266,24 @@ def get_jdk_system(java_toolchain, javac_opts):
     # TODO(b/197211878): Switch to a public API when available.
     return java_toolchain._bootclasspath_info._system_inputs.to_list() if not jdk_system_already_set else []
 
+def _add_profiling_support(ctx, mnemonic, outputs, args):
+    if ctx.attr._profiling_filter[BuildSettingInfo].value in str(ctx.label):
+        profile_output = ctx.actions.declare_file(ctx.label.name + "_" + mnemonic + ".profile")
+        outputs.append(profile_output)
+        args.add("-profileOutput", profile_output)
+        print("Profiling %s %s" % (ctx.label, mnemonic))  # buildifier: disable=print
+        print("pprof --flame %s" % profile_output.path)  # buildifier: disable=print
+
 def _strip_incompatible_annotation(ctx, name, java_srcs, mnemonic, strip_annotations):
     # Paths are matched by Kythe to identify generated J2CL sources.
     output_file = ctx.actions.declare_file(name + "_j2cl_stripped-src.jar")
 
+    mnemonic = mnemonic + "Strip"
+    outputs = [output_file]
     args = ctx.actions.args()
     args.use_param_file("@%s", use_always = True)
     args.set_param_file_format("multiline")
+    _add_profiling_support(ctx, mnemonic, outputs, args)
     args.add("-d", output_file)
     args.add_all(strip_annotations, format_each = "-annotation=%s")
     args.add_all(java_srcs)
@@ -281,15 +292,15 @@ def _strip_incompatible_annotation(ctx, name, java_srcs, mnemonic, strip_annotat
     ctx.actions.run(
         progress_message = "Stripping %s from %s" % (formatted_annotations, name),
         inputs = java_srcs,
-        outputs = [output_file],
+        outputs = outputs,
         executable = ctx.executable._j2cl_stripper,
         arguments = [args],
         env = dict(LANG = "en_US.UTF-8"),
         execution_requirements = {
             "supports-multiplex-workers": "1",
             "supports-multiplex-sandboxing": "1",
         },
-        mnemonic = mnemonic + "Strip",
+        mnemonic = mnemonic,
     )
 
     return output_file
@@ -355,6 +366,7 @@ def _j2cl_transpile(
         klib_provider,
         klib_friends):
     """ Takes Java provider and translates it into Closure style JS in a zip bundle."""
+    mnemonic = "J2cl" if backend == "CLOSURE" else "J2wasm"
     is_klibs_enabled = klib_common.is_klibs_experiment_enabled(ctx) and (kt_srcs or kt_common_srcs)
 
     if "-Xstdlib-compilation" in kotlincopts:
@@ -387,6 +399,7 @@ def _j2cl_transpile(
     args = ctx.actions.args()
     args.use_param_file("@%s", use_always = True)
     args.set_param_file_format("multiline")
+    _add_profiling_support(ctx, mnemonic, outputs, args)
     args.add_joined("-classpath", classpath, join_with = ctx.configuration.host_path_separator)
     args.add_all("-system", jdk_system, expand_directories = False)
 
@@ -411,11 +424,6 @@ def _j2cl_transpile(
 
     args.add("-experimentalBackend", backend)
 
-    if ctx.attr._profiling_filter[BuildSettingInfo].value in str(ctx.label):
-        profile_output = ctx.actions.declare_file(ctx.label.name + ".profile")
-        outputs.append(profile_output)
-        args.add("-profileOutput", profile_output)
-
     if backend == "WASM":
         # Add a prefix to where the Java source files will be located relative to the source map.
         args.add(output_dir.short_path, format = "-sourceMappingPathPrefix=%s/")
@@ -465,7 +473,7 @@ def _j2cl_transpile(
             "supports-multiplex-sandboxing": "1",
             "supports-worker-cancellation": "1",
         },
-        mnemonic = "J2cl" if backend == "CLOSURE" else "J2wasm",
+        mnemonic = mnemonic,
     )
 
 def _create_js_lib_struct(j2cl_info, extra_providers = []):
@@ -511,6 +519,9 @@ J2CL_JAVA_TOOLCHAIN_ATTRS = {
         cfg = "exec",
         executable = True,
     ),
+    "_profiling_filter": attr.label(
+        default = Label("//:profiling_filter"),
+    ),
 }
 
 J2CL_TOOLCHAIN_ATTRS = {
@@ -522,9 +533,6 @@ J2CL_TOOLCHAIN_ATTRS = {
     "_java_frontend": attr.label(
         default = Label("//:experimental_java_frontend"),
     ),
-    "_profiling_filter": attr.label(
-        default = Label("//:profiling_filter"),
-    ),
     "_zip": attr.label(
         executable = True,
         cfg = "exec",

tools/java/com/google/j2cl/tools/gwtincompatible/BUILD

@@ -4,7 +4,7 @@
 #   J2CL.
 
 load("@rules_java//java:defs.bzl", "java_binary", "java_library")
-load("//transpiler/java/com/google/j2cl/common/bazel:jvm_flags.bzl", "JVM_FLAGS")
+load("//transpiler/java/com/google/j2cl/common/bazel:compiler_java_binary.bzl", "compiler_java_binary")
 
 package(
     default_applicable_licenses = ["//:j2cl_license"],
@@ -45,11 +45,8 @@ java_library(
     ],
 )
 
-java_binary(
+compiler_java_binary(
     name = "GwtIncompatibleStripper_worker",
-    jvm_flags = JVM_FLAGS,
     main_class = "com.google.j2cl.tools.gwtincompatible.BazelGwtIncompatibleStripper",
-    use_launcher = False,
-    visibility = ["//build_defs:toolchain_users"],
     runtime_deps = [":gwtincompatible_worker_lib"],
 )

transpiler/java/com/google/j2cl/common/bazel/BUILD

@@ -21,3 +21,8 @@ java_library(
         "//transpiler/java/com/google/j2cl/common/bazel/profiler",
     ],
 )
+
+config_setting(
+    name = "profiling_disabled",
+    flag_values = {"//:profiling_filter": "<disabled>"},
+)

…j2cl/transpiler/compiler_java_binary.bzl …cl/common/bazel/compiler_java_binary.bzltranspiler/java/com/google/j2cl/transpiler/compiler_java_binary.bzl renamed to transpiler/java/com/google/j2cl/common/bazel/compiler_java_binary.bzl transpiler/java/com/google/j2cl/transpiler/compiler_java_binary.bzl renamed to transpiler/java/com/google/j2cl/common/bazel/compiler_java_binary.bzl

@@ -1,26 +1,26 @@
 load("@rules_java//java:java_binary.bzl", "java_binary")
-load("//transpiler/java/com/google/j2cl/common/bazel:jvm_flags.bzl", "JVM_FLAGS")
+load(":jvm_flags.bzl", "JVM_FLAGS")
 
-visibility("private")
+visibility(["//..."])
 
 def compiler_java_binary(name, runtime_deps = [], extra_jvm_flags = [], **kwargs):
     java_binary(
         name = name,
         jvm_flags = JVM_FLAGS + extra_jvm_flags + select({
-            ":profiling_disabled": [],
+            "//transpiler/java/com/google/j2cl/common/bazel:profiling_disabled": [],
             "//conditions:default": [
                 "-XX:GoogleAgentFlags=-contentionz,-codez,-histogram,-heapz,-native_heapz," +
                 "cpu_profile_stack_limit:256,cpu_samples:200",
             ],
         }),
         runtime_deps = runtime_deps + select({
-            ":profiling_disabled": [],
+            "//transpiler/java/com/google/j2cl/common/bazel:profiling_disabled": [],
             "//conditions:default": [
                 "//transpiler/java/com/google/j2cl/common/bazel/profiler:profiler_impl",
             ],
         }),
         launcher = select({
-            ":profiling_disabled": None,
+            "//transpiler/java/com/google/j2cl/common/bazel:profiling_disabled": None,
             "//conditions:default": "//devtools/java/launcher:run_java",
         }),
         visibility = ["//build_defs:toolchain_users"],

transpiler/java/com/google/j2cl/transpiler/BUILD

@@ -1,5 +1,5 @@
 load("@rules_java//java:defs.bzl", "java_binary", "java_library")
-load(":compiler_java_binary.bzl", "compiler_java_binary")
+load("//transpiler/java/com/google/j2cl/common/bazel:compiler_java_binary.bzl", "compiler_java_binary")
 
 package(
     default_applicable_licenses = ["//:j2cl_license"],
@@ -125,8 +125,3 @@ compiler_java_binary(
     main_class = "com.google.j2cl.transpiler.BazelJ2wasmBundler",
     runtime_deps = [":bazelj2wasmbundler_lib"],
 )
-
-config_setting(
-    name = "profiling_disabled",
-    flag_values = {"//:profiling_filter": "<disabled>"},
-)