review request (L): 7032323: code changes for JSR 292 EG adjustments to API, through Public Review

[Y. S. Ramakrishna]

John, you state that validity is not a stable property.
Is invalidity a stable property, or not even that is.

-- ramki
(who doesn't yet know what a switchpoint is)

On 05/26/11 10:11, Tom Rodriguez wrote:
> isValid looks fine.
> 
> tom
> 
> On May 26, 2011, at 1:31 AM, John Rose wrote:
> 
>> On May 25, 2011, at 11:58 PM, Tom Rodriguez wrote:
>>
>>> Overall it seems ok.  A few minor oddities:
>>>
>>> MethodHandle.java
>>>
>>> variable arity is sometimes hyphenated.  It seems more correct without but be consistent.
>> Replaced hyphen by space.
>>
>>> AdapterMethodHandle.java:
>>>
>>> The new value srcSlot appears unused.
>> Right; it doesn't have any use.  Deleted.
>>
>>> Should this just go away:
>>>
>>> -        if (argCount <= 2)  return false;  // must be a swap, not a rotate
>>> +        //if (argCount <= 2)  return false;  // must be a swap, not a rotate
>> Yes.  Turns out that if you need to swap an int and a long, it has to be rendered as one or two rotates.
>>
>> Thanks, Tom.
>>
>> -- John
>>
>> P.S.  One more bit to review:  I might add the following to SwitchPoint.java, depending on what the EG says today.
>>
>>    /**
>>     * Determines if this switchpoint is still valid.
>>     * <p>
>>     * Since invalidation is a global and immediate operation,
>>     * this query must be sequenced with any
>>     * other threads that could invalidate this switchpoint.
>>     * It may therefore be expensive.
>>     * <p>
>>     * In addition, due to concurrent invalidations by other threads,
>>     * a switchpoint may report itself as valid, and yet become
>>     * invalid before the querying thread begins to act on the
>>     * supposed validity.
>>     * @return true if this switchpoint has never been invalidated
>>     */
>>    public boolean isValid() {
>>        return (mcs.getTarget() == K_true);
>>    }
>>
>>> tom
>>>
>>> On May 25, 2011, at 3:30 AM, John Rose wrote:
>>>
>>>> This is the last major bundle of changes for JDK 7.
>>>> http://cr.openjdk.java.net/~jrose/7032323/webrev.00/
>>
>