[aarch64-port-dev ] RFR: 8191955: AArch64: incorrect prefetch distance causes an internal error

[White, Derek]

Hi Andrew,

AllocatePrefetchDistanceConstraintFunc is the bounds-checking function for AllocatePrefetchDistance. It's not possible run with -1 specified on the command line (with or without Ningsheng's patch).

> java -XX:AllocatePrefetchDistance=-1 -version
AllocatePrefetchDistance (-1) must be between 0 and 512
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

- Derek

> -----Original Message-----
> From: aarch64-port-dev [mailto:aarch64-port-dev-
> bounces at openjdk.java.net] On Behalf Of Andrew Haley
> Sent: Tuesday, November 28, 2017 8:20 AM
> To: Ningsheng Jian <ningsheng.jian at linaro.org>
> Cc: hotspot compiler <hotspot-compiler-dev at openjdk.java.net>; aarch64-
> port-dev <aarch64-port-dev at openjdk.java.net>
> Subject: Re: [aarch64-port-dev ] RFR: 8191955: AArch64: incorrect prefetch
> distance causes an internal error
> 
> On 28/11/17 10:31, Ningsheng Jian wrote:
> > OK, AllocatePrefetchDistanceConstraintFunc has constraint to make sure
> > it should be [0, 512], which does not match document...
> 
> OK, but this patch is about AllocatePrefetchDistance.  Does your patch work
> with -1?
> 
> --
> Andrew Haley
> Java Platform Lead Engineer
> Red Hat UK Ltd. <https://www.redhat.com>
> EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671