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

[Yingchi Long via cfe-commits]

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@@ -0,0 +1,106 @@
+; RUN: llc < %s -march=bpfel -mcpu=v4 -verify-machineinstrs -show-mc-encoding \
+; RUN:   | FileCheck -check-prefixes=CHECK-LE %s
+; RUN: llc < %s -march=bpfeb -mcpu=v4 -verify-machineinstrs -show-mc-encoding \
+; RUN:   | FileCheck -check-prefixes=CHECK-BE %s
+
+; Source:
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inclyc wrote:

This IR file is simple enough, thus doesn't need the source.

Usually when testing a single instruction, we just write the IR files by hands, instead of generating them from clang.

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