RFR: 8296630: Fix SkipIfEqual on AArch64 and RISC-V [v2]

[Andrew Haley]

On Fri, 11 Nov 2022 08:34:10 GMT, Yadong Wang <yadongwang at openjdk.org> wrote:

>> SkipIfEqual was supposed to load a flag value from some memory, compare it with a input boolean value, and jump to a specific label they a equals. The implementation on x86 and s390 platforms meets expectations, and ppc uses SkipIfEqualZero. However, on AArch64 and RISC-V platforms, the input argument "value" is not used, and jumping-if-equal-zero is generated only. That's not correct, but works well since only false passed on all call sites so far.
>> 
>> AArch64 tier1, riscv hotspot & jdk tier1 have been tested.
>> Additional cases with dtrace tested on AArch64:
>> test/hotspot/jtreg/serviceability/dtrace/DTraceOptionsTest.java
>> test/hotspot/jtreg/compiler/runtime/Test8168712.java
>
> Yadong Wang has updated the pull request incrementally with one additional commit since the last revision:
> 
>   reverse branch order

Marked as reviewed by aph (Reviewer).

-------------

PR: https://git.openjdk.org/jdk/pull/11076