[clang] [llvm] [compiler-rt] [AArch64][SME] Add support for sme-fa64 (PR #70809)

[Sander de Smalen via cfe-commits]

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@@ -0,0 +1,33 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mattr=+sve -mattr=+sme-fa64 -force-streaming-compatible-sve < %s | FileCheck %s -check-prefix=FA64
+; RUN: llc -mattr=+sve -force-streaming-compatible-sve < %s | FileCheck %s -check-prefix=NO-FA64
+
+
+target triple = "aarch64-unknown-linux-gnu"
+
+define half @fadda_v4f16(half %start, <4 x half> %a) {
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sdesmalen-arm wrote:

Could you add a similar test where a Neon instruction would be used when `sme-fa64` is set? (and where it would be scalarised otherwise)

https://github.com/llvm/llvm-project/pull/70809