[clang] [llvm] [X86] Enable HasFastHalfType to prevent FP16 promotion and perform FABS/FNEG lowering (PR #189395)

[Simon Pilgrim via cfe-commits]

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@@ -0,0 +1,46 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+sse2 | FileCheck %s --check-prefixes=SSE2
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+avx | FileCheck %s --check-prefixes=AVX
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+f16c | FileCheck %s --check-prefixes=F16C
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RKSimon wrote:

we should be testing this with fast-isel

https://github.com/llvm/llvm-project/pull/189395