[llvm] [AArch64][Build Attributes] Improve Parsing and Formatting (PR #126530)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,50 @@
+// RUN: llvm-mc -triple=aarch64 %s -o - | FileCheck %s --check-prefix=ASM
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MaskRay wrote:

For llvm-mc, omit `-o -` (default)

https://github.com/llvm/llvm-project/pull/126530