[aarch64-port-dev ] RFR: AArch64: -XX:-UseOnStackReplacement does not work together with -XX:+TieredCompilation.

[Andrew Haley]

On 25/07/16 10:22, Ningsheng Jian wrote:
> otspot patch [1] introduces a test case
> hotspot/test/compiler/interpreter/DisableOSRTest.java which also
> exposes the same issue on aarch64.
> 
> I.e. with -XX:-UseOnStackReplacement and -XX:+TieredCompilation
> options, there are still OSR compilations found from
> -XX:+PrintCompilation.
> 
> On x86, the increment_mask_and_jump just jumps to the next instruction
> if backedge_counter_overflow is not generated. So there is no such
> issue - but is it intended?
> 
> The following fix on AArch64 is to revert [2] to align with x86 code
> and assign the correct branch target based on the
> UseOnStackReplacement option.
> 
> http://people.linaro.org/~ningsheng.jian/disable-osr/webrev.00/

The patch is good, thanks.

Darn, I missed this patch.  Looks like it missed JDK 9.  We'll sort
this out when JDK 10 is fully open for business.

Andrew.