[llvm] [X86] Reimplement bundle alignment mode (PR #175830)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,57 @@
+# RUN: llvm-mc -filetype=obj -triple x86_64 %s -o - \
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MaskRay wrote:

Drop `-o -` from llvm-mc lines here and everywhere

https://github.com/llvm/llvm-project/pull/175830