[llvm] [MCA] Fix -mcpu=help flag (PR #173399)

[Aiden Grossman via llvm-commits]

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@@ -0,0 +1,9 @@
+# REQUIRES: aarch64-registered-target
+
+# RUN: llvm-mca -mtriple=aarch64-unknown-linux-gnu -mcpu=help %t.no-input 2>&1 | FileCheck %s
+
+// Ensures -mcpu=help prints target info without erroring on missing input.
+
+# CHECK: Available CPUs for this target:
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boomanaiden154 wrote:

Can we assert a CPU or two to ensure that the printing actually happens?

https://github.com/llvm/llvm-project/pull/173399