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

[David Green 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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davemgreen wrote:

Yes that sounds right. It is needed to make the patterns match properly, as a bfcvtn will naturally produce a 64bit vector, and v4bf16 is a 64bit vector. Other instructions that use SIMDMixedTwoVector like XTN use the same type.

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