Improve polybench usage and launcher help messages

Author: DSouzaM

truffle/mx.truffle/mx_polybench/command.py

@@ -69,9 +69,9 @@ def parser_help_message(cls):
         return (
             "additional benchmark arguments. By default, arguments are passed to the Polybench launcher, "
             f"but you may use flags to forward arguments to specific components: "
-            f"{cls.MX_BENCHMARK_FLAG} for mx benchmark, "
-            f"{cls.VM_FLAG} for the host VM or native-image, or "
-            f"{cls.POLYBENCH_FLAG} for the Polybench launcher. "
+            f'"{cls.MX_BENCHMARK_FLAG}" for mx benchmark, '
+            f'"{cls.VM_FLAG}" for the host VM or native-image, or '
+            f'"{cls.POLYBENCH_FLAG}" for the Polybench launcher (pass "--help" to see launcher help). '
             f'For example: "-i 2 {cls.MX_BENCHMARK_FLAG} --fail-fast {cls.VM_FLAG} -ea '
             f'{cls.POLYBENCH_FLAG} --engine.TraceCompilation=true".'
         )
@@ -410,6 +410,7 @@ def _create_parser() -> ArgumentParser:
             "It is a thin wrapper around Polybench's mx benchmark integration that makes it easy to discover and run benchmarks. "
             "It also supports batch execution of the benchmarks in a suite, which is convenient for defining CI jobs."
         ),
+        usage="%(prog)s [options*] benchmarks [benchmark_arguments*]",
     )
 
     parser.add_argument(

truffle/src/org.graalvm.polybench/src/org/graalvm/polybench/PolyBenchLauncher.java

@@ -314,6 +314,16 @@ protected void printHelp(OptionCategory maxCategory) {
         }
     }
 
+    /**
+     * Suppress the runtime options printed by the parent implementation. Some of these options
+     * (like --jvm, --native) are handled by mx polybench, so using them in the launcher is
+     * discouraged (and confusing).
+     */
+    @Override
+    protected void printDefaultHelp(OptionCategory helpCategory) {
+        printHelp(helpCategory);
+    }
+
     static String getExtension(String path) {
         int lastDot = path.lastIndexOf('.');
         if (lastDot < 0) {