RFR(S): : 8211332: Space for stub routines (code_size2) is too small on new Skylake CPUs

[Vladimir Kozlov]

+1

Thanks,
Vladimir

On 10/2/18 3:53 AM, Thomas Stüfe wrote:
> This looks good. Thanks for fixing!
> 
> Best Regards, Thomas
> On Tue, Oct 2, 2018 at 12:37 PM Schmelter, Ralf <ralf.schmelter at sap.com> wrote:
>>
>> Please review this change which increases the space available for stub routines on Windows x86.
>>
>>
>>
>> bug: https://bugs.openjdk.java.net/browse/JDK-8211332<https://bugs.openjdk.java.net/browse/JDK-8211350>
>>
>> webrev: http://cr.openjdk.java.net/~clanger/webrevs/8211332.0/
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>>
>>
>> My Windows x86 slowdebug build crashed in StubRoutines::initialize1(), since the estimated code size (code_size2 defined in stub_routines_x86.hpp) for the initial stubs was too low. I've increase code_size2 by 500 bytes per step, until the assertions vanished.
>>
>>
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>> This seems to be 'caused' the new -XX:UseBASE64Intrinsics flag, which is only turned on if the machine supports the AVX-512VL and AVX-512BW extensions, which is the case for Skylake-SP and Skylake X and later/better CPUs.
>>
>>
>>
>> Best regards,
>>
>> Ralf Schmelter