[llvm] [SFrames] Emit and relax FREs (PR #158154)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,87 @@
+// TODO: Add other architectures as they gain sframe support
+// REQUIRES: x86-registered-target
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MaskRay wrote:

MC/ELF/lit.local.cfg tests X86. `// REQUIRES: x86-registered-target` is not needed

Delete this TODO. Support for other architectures generally go to test/MC/$arch/

In newer tests, `# ` is more popular as RUN/CHECK prefixes and `## ` is for regular comments.

`llvm-mc` doesn't need `--assemble`

https://github.com/llvm/llvm-project/pull/158154