Hotspot-compiled code on UltraSparcIII and IV can make bad conversions from long to float. It passes arguments incorrectly to SharedRuntime::l2f .

Problem is in 1.5.0_02 and not in 1.4.2_07.

Simple testcase below. Problem output:

(5.10)$ java -server -Xcomp Test
result 0 = 40.0
result 1 = 1.71798757E11
result 2 = 1.71798757E11
result 3 = 1.71798757E11
...testcase continues (showing wrong answers)...

problem: java -server -Xcomp Test
no problem: java -client -Xcomp Test

The testcase pauses for a keypress, for attaching debuggers.

Problem happens on US-III+ and US-IV, not on an Ultra-1, for example.

Testcase code below, attached is a version with additional comments.

----- start of testcase
$ cat Test.java

class Test {

        float [] fresults = new float[50];
        int fc = 0;

// variable names copied from SizeRequirements.java's expandedTile function:

        private void smallTest (int allocated, long min, long pref, long max ) {
                float totalPlay = Math.min(allocated - pref, max - pref);
                fresults[fc] = totalPlay;
                fc++;
        }


        public Test() {

        for (int i=0; i<5; i++) {
                smallTest(88, 48, 48, 65582);
                smallTest(88, 48, 48, 65582);
                smallTest(88, 48, 48, 65582);
        }
        for (int i=0; i<15; i++) {
                System.out.println("result " + i + " = " + fresults[i]);
        }

        try {
                int x = System.in.read();
        } catch (Exception e) {
        }

        fc = 0;
        for (int i=0; i<5; i++) {
                smallTest(88, 48, 48, 65582);
                smallTest(88, 48, 48, 65582);
                smallTest(88, 48, 48, 65582);
        }
        for (int i=0; i<15; i++) {
                System.out.println("result " + i + " = " + fresults[i]);
        }

        } // end constructor

        public static void main(String [] args) {
                Test t = new Test();
        } // end main



} // end class



----- end of testcase


This bug has a graphic side effect:

Swing menus are blank with -server -Xcomp in Java 1.5 on UltraSparcIII and IV.

.jpg attached.

Pull-down menus in Swing applications are blank in Java 1.5, if running with the JVM option -Xcomp.


Testcase:
java -server -Xcomp -jar ..../demo/jfc/SwingSet2/SwingSet2.jar

Workaround:

 .hotspot_compiler
exclude javax/swing/SizeRequirements expandedTile

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###@###.### 2005-03-24 16:40:46 GMT