Try adding armv8-a+lse

[kunalspathak]

Try and see if +lse is possible using clang9. If it is then for linux/arm64, we can just use !g_arm64_atomics_present check to call __sync_synchronize().

[ghost]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[kunalspathak]

Hhm, this might still be problematic for machines that doesn't have LSE because compiler, with +lse will always generate casal instruction and we will get errors like:

exit code 132 means SIGILL Illegal Instruction. Core dumped. Likely codegen issue.

[ghost]

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Issue Details

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Try and see if +lse is possible using clang9. If it is then for linux/arm64, we can just use !g_arm64_atomics_present check to call __sync_synchronize().

Author:	kunalspathak
Assignees:	kunalspathak
Labels:	area-CodeGen-coreclr
Milestone:	-

[kunalspathak]

Replaced by #71512