[clang] [llvm] [AArch64] Improve bcvtn2 and remove aarch64_neon_bfcvt intrinsics (PR #120363)

[Sjoerd Meijer via llvm-commits]

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@@ -9053,22 +9053,19 @@ class SIMDThreeSameVectorBF16MatrixMul<string asm>
 
 let mayRaiseFPException = 1, Uses = [FPCR] in
 class SIMD_BFCVTN
-  : BaseSIMDMixedTwoVector<0, 0, 0b10, 0b10110, V128, V128,
+  : BaseSIMDMixedTwoVector<0, 0, 0b10, 0b10110, V128, V64,
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sjoerdmeijer wrote:

I haven't looked at how this change is used in the base class to be honest, but is my guess correct that due to this change, we see this line disappearing in llvm/test/CodeGen/AArch64/bf16-v4-instructions.ll:

    kill: def $d0 killed $d0 killed $q0

https://github.com/llvm/llvm-project/pull/120363