[clang] [llvm] [BPF] Add load-acquire and store-release instructions under -mcpu=v4 (PR #108636)

[Peilin Ye via cfe-commits]

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@@ -0,0 +1,142 @@
+; RUN: llc < %s -march=bpfel -mcpu=v4 -verify-machineinstrs -show-mc-encoding \
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peilin-ye wrote:

> again

Thanks for pointing this out, but I do want to test the MC encoding.  It looks like at the moment a lot of tests under `llvm/test/CodeGen/BPF/` are doing this:

```shell
$ git grep --files-with-matches '\-show-mc-encoding' -- llvm/test/CodeGen/BPF/ | wc -l
18
```

I think we can do a separate PR to move all the "test MC encoding" bits from `llvm/test/CodeGen/BPF/` to `llvm/test/MC/BPF/`, if needed.

https://github.com/llvm/llvm-project/pull/108636