8024517: runtime/CDSCompressedKPtrs/XShareAuto.java failed with RuntimeException

Summary: Make sure CDS is off by default when running server compiler.
Reviewed-by: dholmes, coleenp

src/share/vm/runtime/arguments.cpp

@@ -1096,6 +1096,7 @@ void Arguments::set_mode_flags(Mode mode) {
   }
 }
 
+#if defined(COMPILER2) || defined(_LP64) || !INCLUDE_CDS
 // Conflict: required to use shared spaces (-Xshare:on), but
 // incompatible command line options were chosen.
 
@@ -1108,6 +1109,7 @@ static void no_shared_spaces() {
     FLAG_SET_DEFAULT(UseSharedSpaces, false);
   }
 }
+#endif
 
 void Arguments::set_tiered_flags() {
   // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
@@ -1492,16 +1494,18 @@ void Arguments::set_ergonomics_flags() {
         FLAG_SET_ERGO(bool, UseParallelGC, true);
       }
     }
-    // Shared spaces work fine with other GCs but causes bytecode rewriting
-    // to be disabled, which hurts interpreter performance and decreases
-    // server performance.   On server class machines, keep the default
-    // off unless it is asked for.  Future work: either add bytecode rewriting
-    // at link time, or rewrite bytecodes in non-shared methods.
-    if (!DumpSharedSpaces && !RequireSharedSpaces &&
-        (FLAG_IS_DEFAULT(UseSharedSpaces) || !UseSharedSpaces)) {
-      no_shared_spaces();
-    }
   }
+#ifdef COMPILER2
+  // Shared spaces work fine with other GCs but causes bytecode rewriting
+  // to be disabled, which hurts interpreter performance and decreases
+  // server performance.  When -server is specified, keep the default off
+  // unless it is asked for.  Future work: either add bytecode rewriting
+  // at link time, or rewrite bytecodes in non-shared methods.
+  if (!DumpSharedSpaces && !RequireSharedSpaces &&
+      (FLAG_IS_DEFAULT(UseSharedSpaces) || !UseSharedSpaces)) {
+    no_shared_spaces();
+  }
+#endif
 
 #ifndef ZERO
 #ifdef _LP64

test/runtime/CDSCompressedKPtrs/XShareAuto.java

@@ -33,16 +33,9 @@ import com.oracle.java.testlibrary.*;
 
 public class XShareAuto {
     public static void main(String[] args) throws Exception {
-        if (!Platform.is64bit()) {
-            System.out.println("ObjectAlignmentInBytes for CDS is only " +
-                "supported on 64bit platforms; this plaform is " +
-                System.getProperty("sun.arch.data.model"));
-            System.out.println("Skipping the test");
-            return;
-        }
         ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
-            "-XX:+UnlockDiagnosticVMOptions", "-XX:SharedArchiveFile=./sample.jsa",
-            "-Xshare:dump");
+            "-server", "-XX:+UnlockDiagnosticVMOptions",
+            "-XX:SharedArchiveFile=./sample.jsa", "-Xshare:dump");
         OutputAnalyzer output = new OutputAnalyzer(pb.start());
         output.shouldContain("Loading classes to share");
         output.shouldHaveExitValue(0);