[llvm] [AArch64] Only create called thunks when hardening against SLS (PR #97472)

[Kristof Beyls via llvm-commits]

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@@ -46,13 +40,5 @@ body:             |
 
 
 ...
----
-name:            __llvm_slsblr_thunk_x8
-tracksRegLiveness: true
-body:             |
-  bb.0.entry:
-    liveins: $x8
 
-    BR $x8
----------------
kbeyls wrote:

ah, yes, I was confused and didn't spot these were input lines....
I looked a bit more now at all of the existing SLS-hardening tests, and the content of the thunk is already tested in https://github.com/llvm/llvm-project/blob/f15266e9d5d87a291a515064f8f0dd5f0c412ed3/llvm/test/CodeGen/AArch64/speculation-hardening-sls.ll#L195

So, there isn't really a need to test for it separately here.
Apologies for giving you more work here!

I think it's fine for the test to go in as is; and it's equally fine for the test to go in without the CHECK lines for the content of the thunk. I'll leave it to you to make that decision.

https://github.com/llvm/llvm-project/pull/97472