Add an inlining stage for single callsite methods

.github/workflows/main.yml

@@ -130,7 +130,7 @@ jobs:
           - os: ubuntu-24.04
             env:
               JDK_VERSION: "latest"
-              GATE_TAGS: "build,debuginfotest"
+              GATE_TAGS: "build,debuginfotest,scismoketest"
               PRIMARY: "substratevm"
           - env:
               JDK_VERSION: "latest"

substratevm/mx.substratevm/mx_substratevm.py

@@ -262,6 +262,7 @@ def __getattr__(self, name):
     'terminus',
     'debuginfotest',
     'standalone_pointsto_unittests',
+    'scismoketest',
     'native_unittests',
     'all_native_unittests',
     'java_desktop_integration',
@@ -508,6 +509,11 @@ def svm_gate_body(args, tasks):
                 with native_image_context(IMAGE_ASSERTION_FLAGS) as native_image:
                     layereddebuginfotest(['--output-path', svmbuild_dir()] + args.extra_image_builder_arguments)
 
+    with Task('image scismoketest', tasks, tags=[GraalTags.scismoketest]) as t:
+        if t:
+            with native_image_context(IMAGE_ASSERTION_FLAGS) as native_image:
+                scismoketest(['--output-path', svmbuild_dir()] + args.extra_image_builder_arguments)
+
     with Task('image debughelpertest', tasks, tags=[GraalTags.debuginfotest]) as t:
         if t:
             if mx.is_windows():
@@ -1482,6 +1488,117 @@ def testhello_ni_args(cincludepath, sourcepath):
         '-H:DebugInfoSourceSearchPath=' + sourcepath,
     ])
 
+
+def _run_scismoke_binary(binary_path):
+    expected_output = 'PASS' + os.linesep
+    actual_output = []
+
+    def _collector(x):
+        actual_output.append(x)
+        mx.log(x)
+
+    mx.run([binary_path], out=_collector)
+
+    # Basic correctness check.
+    if ''.join(actual_output) != expected_output:
+        mx.abort('Unexpected output: ' + str(actual_output) + ' != ' + str([expected_output]))
+
+
+class _ScismokeHistogramTracker:
+    _HISTOGRAM_HEADER = 'Code Size; Nodes Parsing'
+    _HISTOGRAM_FOOTER = 'Size all methods'
+
+    def __init__(self):
+        self.in_histogram = False
+        self.has_single = False
+        self.has_multi = False
+        self.verified_histogram = False
+
+    def process_line(self, line):
+        # Only verify within method histogram bounds.
+        if line.startswith(self._HISTOGRAM_HEADER):
+            self.in_histogram = True
+            self.verified_histogram = True
+        elif self.in_histogram:
+            if line.startswith(self._HISTOGRAM_FOOTER):
+                self.in_histogram = False
+            else:
+                if 'singleCallsiteHelper' in line:
+                    self.has_single = True
+                if 'multiCallsiteHelper' in line:
+                    self.has_multi = True
+
+
+def _find_methodhistogram_file(reports_dir):
+    matches = glob(join(reports_dir, 'methodhistogram_*.txt'))
+    if not matches:
+        return None
+    return max(matches, key=os.path.getmtime)
+
+
+def _parse_methodhistogram_file(histogram_file):
+    tracker = _ScismokeHistogramTracker()
+    with open(histogram_file, 'r', encoding='utf-8') as histogram:
+        for line in histogram:
+            tracker.process_line(line.rstrip('\n'))
+    return tracker
+
+
+def _build_scismoke_image(native_image, build_args, reports_dir):
+    def _log_output(line):
+        mx.log(line)
+
+    native_image(build_args, out=_log_output, err=_log_output)
+    histogram_file = _find_methodhistogram_file(reports_dir)
+    if histogram_file is None:
+        mx.abort('PrintMethodHistogram report not found in ' + reports_dir)
+    mx.log('Parsing method histogram from: ' + histogram_file)
+    tracker = _parse_methodhistogram_file(histogram_file)
+    if not tracker.verified_histogram:
+        mx.abort('PrintMethodHistogram output not found in ' + histogram_file)
+    return tracker
+
+
+def _assert_scismoke_histogram(tracker, is_sci_enabled, variant_name):
+    if not tracker.has_multi:
+        mx.abort(variant_name + ': multiCallsiteHelper should always appear in histogram')
+    if is_sci_enabled:
+        if tracker.has_single:
+            mx.abort(variant_name + ': singleCallsiteHelper should not appear in histogram with SCI enabled')
+    elif not tracker.has_single:
+        mx.abort(variant_name + ': singleCallsiteHelper should appear in histogram with SCI disabled')
+
+
+def _scismoketest(native_image, path, args):
+    mx_util.ensure_dir_exists(path)
+
+    base_args = [
+        '--native-image-info',
+        '-cp', classpath('com.oracle.svm.test.sci'),
+        '--initialize-at-build-time=com.oracle.svm.test.sci',
+        'com.oracle.svm.test.sci.SciSmoke',
+    ] + args
+
+    def build_and_run(variant_name, sci_flag, is_sci_enabled):
+        variant_path = join(path, variant_name)
+        mx_util.ensure_dir_exists(variant_path)
+        binary_path = join(variant_path, 'scismoke')
+        build_args = base_args + svm_experimental_options([
+            sci_flag,
+            '-H:+PrintMethodHistogram',
+        ]) + [
+            '-o', binary_path,
+        ]
+        reports_dir = join(variant_path, 'reports')
+        mx.log(f'native_image {build_args}')
+        tracker = _build_scismoke_image(native_image, build_args, reports_dir)
+        _assert_scismoke_histogram(tracker, is_sci_enabled, variant_name)
+        _run_scismoke_binary(binary_path)
+
+    build_and_run('sci_on', '-H:+AOTSingleCallsiteInline', True)
+    build_and_run('sci_off', '-H:-AOTSingleCallsiteInline', False)
+
+
 def _gdbdebughelperstest(native_image, path, with_isolates_only, args):
 
     # ====== check gdb version ======
@@ -2386,6 +2503,25 @@ def run_helloworld_command(args, config, command_name, native_image_wrapper=None
         config=config,
     )
 
+@mx.command(suite_name=suite.name, command_name='scismoketest', usage_msg='[options]')
+def scismoketest(args, config=None):
+    """
+    Build and run a simple app with AOTSingleCallsiteInline enabled and disabled.
+    The output of the app is verified for correctness.
+    PrintMethodHistogram is parsed to verify the expected inlining happened.
+    """
+    parser = ArgumentParser(prog='mx scismoketest')
+    all_args = ['--output-path', '--build-only']
+    masked_args = [_mask(arg, all_args) for arg in args]
+    parser.add_argument(all_args[0], metavar='<output-path>', nargs=1, help='Path of the generated image', default=[svmbuild_dir()])
+    parser.add_argument('image_args', nargs='*', default=[])
+    parsed = parser.parse_args(masked_args)
+    output_path = unmask(parsed.output_path)[0]
+    native_image_context_run(
+        lambda native_image, a:
+            _scismoketest(native_image, output_path, a), unmask(parsed.image_args),
+        config=config
+    )
 
 @mx.command(suite_name=suite.name, command_name='debuginfotest', usage_msg='[options]')
 def debuginfotest(args, config=None):

substratevm/mx.substratevm/suite.py

@@ -1274,6 +1274,19 @@
             "testProject": True,
         },
 
+        "com.oracle.svm.test.sci": {
+            "subDir": "src",
+            "sourceDirs": ["src"],
+            "dependencies": [
+                "SVM",
+            ],
+            "checkstyle": "com.oracle.svm.test",
+            "workingSets": "SVM",
+            "javaCompliance": "22+",
+            "spotbugs": "false",
+            "jacoco": "exclude",
+        },
+
         "com.oracle.svm.with.space.test": {
             "subDir": "src",
             "sourceDirs": ["src"],

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/SubstrateOptions.java

@@ -1,5 +1,6 @@
 /*
- * Copyright (c) 2013, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2026, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2026, 2026, IBM Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -891,6 +892,10 @@ public static long getTearDownFailureNanos() {
     @Option(help = "Perform trivial method inlining in the AOT compiled native image")//
     public static final HostedOptionKey<Boolean> AOTTrivialInline = new HostedOptionKey<>(true);
 
+    @LayerVerifiedOption(kind = Kind.Changed, severity = Severity.Error)//
+    @Option(help = "Perform single callsite method inlining in the AOT compiled native image", stability = OptionStability.EXPERIMENTAL)//
+    public static final HostedOptionKey<Boolean> AOTSingleCallsiteInline = new HostedOptionKey<>(false);
+
     @LayerVerifiedOption(kind = Kind.Removed, severity = Severity.Warn, positional = false)//
     @Option(help = "file:doc-files/NeverInlineHelp.txt", type = OptionType.Debug)//
     public static final HostedOptionKey<AccumulatingLocatableMultiOptionValue.Strings> NeverInline = new HostedOptionKey<>(AccumulatingLocatableMultiOptionValue.Strings.build());

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/code/CompilationInfo.java

@@ -1,5 +1,6 @@
 /*
- * Copyright (c) 2013, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2026, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2026, 2026, IBM Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,6 +26,7 @@
 package com.oracle.svm.hosted.code;
 
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 
 import com.oracle.graal.pointsto.flow.AnalysisParsedGraph;
@@ -45,6 +47,9 @@
 import jdk.graal.compiler.options.OptionValues;
 
 public class CompilationInfo {
+    int sizeLastRound;
+
+    AtomicInteger callsites = new AtomicInteger();
 
     protected final HostedMethod method;