Request for reviews (M): 8001183: incorrect results of char vectors right shift operaiton
dean.long at oracle.com
Mon Oct 22 22:00:58 PDT 2012
The @summary for the new TestShortVector.java mentions "char" not "short".
What is this new short test checking for (I thought the bug was only
If there is a problem with shorts too, then wouldn't we need a test for
On 10/22/2012 04:13 PM, Vladimir Kozlov wrote:
> In java when small integer values are loaded they are converted to Int
> with sign extension for byte and short or with zero extension for
> boolean and char. Any following arithmetic operation may produce
> result which will not fit into value of the original type. Because of
> that right shift vector operations produce incorrect result when they
> operate on not just loaded data.
> Generate right shift vector operations only if the preceding operation
> is load.
> To get correct result of boolean and char vectors arithmetic right
> shift operation we should use unsigned right shift operation.
> Disable unsigned right shift for vectors with signed elements (byte,
> short) in shared code since they are not valid on all platforms.
> Added new regression tests prepared by Dean Long and me.
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