[clang] [AArch64][SME2] Enable bfm builtins for sme2 (PR #71927)

[Sam Tebbs via cfe-commits]

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@@ -1992,3 +1986,12 @@ let TargetGuard = "sme2" in {
   def SVADD_SINGLE_X2 : SInst<"svadd[_single_{d}_x2]", "22d", "cUcsUsiUilUl", MergeNone, "aarch64_sve_add_single_x2", [IsStreaming], []>;
   def SVADD_SINGLE_X4 : SInst<"svadd[_single_{d}_x4]", "44d", "cUcsUsiUilUl", MergeNone, "aarch64_sve_add_single_x4", [IsStreaming], []>;
 }
+
+let TargetGuard = "sve2p1|sme2" in {
+// == BFloat16 multiply-subtract ==
+  def SVBFMLSLB : SInst<"svbfmlslb[_{d}]", "dd$$", "f", MergeNone, "aarch64_sve_bfmlslb", [IsOverloadNone], []>;
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SamTebbs33 wrote:

That makes sense :+1: 

https://github.com/llvm/llvm-project/pull/71927