8034775: Failing to initialize VM when running with negative value for -XX:CICompilerCount

Summary: Ensure appropriate min. number of compiler threads (1 for non-tiered, and 2 for tiered)
Reviewed-by: kvn

src/share/vm/runtime/arguments.cpp

@@ -2462,6 +2462,10 @@ bool Arguments::check_vm_args_consistency() {
   status &= verify_interval(SafepointPollOffset, 0, os::vm_page_size() - BytesPerWord, "SafepointPollOffset");
 #endif
 
+  // TieredCompilation needs at least 2 compiler threads.
+  const int num_min_compiler_threads = (TieredCompilation) ? 2 : 1;
+  status &=verify_min_value(CICompilerCount, num_min_compiler_threads, "CICompilerCount");
+
   return status;
 }
 

test/compiler/startup/NumCompilerThreadsCheck.java

+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8034775
+ * @summary Ensures correct minimal number of compiler threads (provided by -XX:CICompilerCount=)
+ * @library /testlibrary
+ */
+import com.oracle.java.testlibrary.*;
+
+public class NumCompilerThreadsCheck {
+  public static void main(String[] args) throws Exception {
+    ProcessBuilder pb = ProcessTools.createJavaProcessBuilder("-XX:CICompilerCount=-1");
+    OutputAnalyzer out = new OutputAnalyzer(pb.start());
+
+    String expectedOutput = "CICompilerCount of -1 is invalid";
+    out.shouldContain(expectedOutput);
+  }
+}