[llvm] [X86] Promote approximate v8f16 FMA to v8f32 (PR #228900)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,1048 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mcpu=x86-64-v2 | FileCheck %s --check-prefix=NOFMA
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mcpu=x86-64-v3 | FileCheck %s --check-prefix=FMA
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mcpu=x86-64-v4 -mattr=+avx512fp16 | FileCheck %s --check-prefix=FP16
+
+; Check v8f16 FMA lowering with approximate, exact, and native FP16 paths.
+
+define <8 x half> @afn_fma(<8 x half> %a, <8 x half> %b, <8 x half> %c) nounwind {
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RKSimon wrote:

Rename to fma-anf-vXf16.ll and add some similar tests other vector types (e.g. v4f16/v16f16) to ensure legalization is working correctly

https://github.com/llvm/llvm-project/pull/228900