RFR: 8324734: Remove too-strict assert(VM_Version::supports_evex()) in Assembler::locate_operand()

[Vladimir Kozlov]

On Fri, 26 Jan 2024 15:18:39 GMT, Roman Kennke <rkennke at openjdk.org> wrote:

> Details see bug report. The gist is that HotSpot downgrades to UseAVX=2 on some processors, and reports supports_evex() == false, but the instruction decoder can still encounter EVEX instructions when (e.g.) hitting a SIGBUS in memset() - which does have EVEX instructions.
> 
> Testing:
>  - [x] runtime/Unsafe/InternalErrorTest.java
>  - [x] tier1

The assert is there to make sure HotSpot generates correct code.
What output you get in your test case with this change? You still crash in `memset`.

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PR Review: https://git.openjdk.org/jdk/pull/17590#pullrequestreview-1846415132