[llvm] [AArch64][SME] Lower memchr to __arm_sc_memchr in streaming[-compatible] functions (PR #168896)

[Benjamin Maxwell via llvm-commits]

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@@ -153,6 +153,160 @@ entry:
   ret void
 }
 
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MacDue wrote:

Added a test case :+1: 

https://github.com/llvm/llvm-project/pull/168896