[llvm] [AMDGPU] Add custom lowering of llvm.convert.from.arbitrary.fp for FP8 (PR #194144)

[Dmitry Sidorov via llvm-commits]

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@@ -0,0 +1,102 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc < %s -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1250 | FileCheck -check-prefix=GFX1250 %s
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MrSidims wrote:

Ah, apologies, I took at quick glance at [arbitrary-fp-to-float.ll#L11](https://github.com/llvm/llvm-project/blob/main/llvm/test/CodeGen/AMDGPU/arbitrary-fp-to-float.ll#L11C15-L11C52) and assumed it's tested. But existing testing is not enough. Will extend it.

https://github.com/llvm/llvm-project/pull/194144