8237542: JMapHeapConfigTest.java doesn't work with negative jlong values

Reviewed-by: sspitsyn, shade

src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/tools/HeapSummary.java

@@ -280,14 +280,10 @@ public class HeapSummary extends Tool {
       printValMB(System.out, title, value);
    }
 
-   private static final double FACTOR = 1024*1024;
    private void printValMB(PrintStream tty, String title, long value) {
-      if (value < 0) {
-        tty.println(alignment + title +   (value >>> 20)  + " MB");
-      } else {
-        double mb = value/FACTOR;
-        tty.println(alignment + title + value + " (" + mb + "MB)");
-      }
+       double valueMB = value >>> 20;  // unsigned divide by 1024*1024
+       String valueUnsigned = Long.toUnsignedString(value, 10);
+       tty.println(alignment + title + valueUnsigned + " (" + valueMB + "MB)");
    }
 
    private void printValue(String title, long value) {

test/jdk/sun/tools/jhsdb/heapconfig/JMapHeapConfigTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2023, 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
@@ -53,15 +53,13 @@ public class JMapHeapConfigTest {
         "MaxHeapFreeRatio",
         "MaxHeapSize",
         "NewSize",
+        "MaxNewSize",
         "OldSize",
         "NewRatio",
         "SurvivorRatio",
         "MetaspaceSize",
-        "CompressedClassSpaceSize"};
-
-    // Test can't deal with negative jlongs:
-    //  ignoring MaxMetaspaceSize
-    //  ignoring MaxNewSize
+        "CompressedClassSpaceSize",
+        "MaxMetaspaceSize"};
 
     static final String desiredMaxHeapSize = "-Xmx128m";
 
@@ -152,6 +150,11 @@ public class JMapHeapConfigTest {
             throw new RuntimeException("Test FAILED jmap exits with non zero exit code " + exitcode);
         }
 
+        System.out.println("Jmap Output:");
+        for (String line : tmt.getToolOutput()) {
+            System.out.println(line);
+        }
+
         Map<String,String> parsedJmapOutput = parseJMapOutput(tmt.getToolOutput());
         Map<String,String> parsedVMOutput = tmt.parseFlagsFinal();