[llvm] AMDGPU: Fix the double rounding issue in v2f64 -> v2f16 conversion (PR #135659)

[Matt Arsenault via llvm-commits]

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+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx950 -global-isel=0 < %s | FileCheck -check-prefixes=GFX950,GFX950-SAFE-SDAG %s
+; RUN: llc -mtriple=amdgcn -mcpu=gfx950 -global-isel=0 < %s | FileCheck -check-prefixes=GFX950,GFX950-SAFE-GISEL %s
+; RUN: llc -mtriple=amdgcn -mcpu=gfx950 -global-isel=0 -enable-unsafe-fp-math < %s | FileCheck -check-prefixes=GFX950,GFX950-UNSAFE %s
+; RUN: llc -mtriple=amdgcn -mcpu=gfx950 -global-isel=0 -enable-unsafe-fp-math < %s | FileCheck -check-prefixes=GFX950,GFX950-UNSAFE %s
+
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arsenm wrote:

Globalisel part untested, this does not have any globalisel=1 run lines. 

Also why the fpmath suffix, this does not involve fpmath metadata 

These cases should just be in the other fptrunc test? 

https://github.com/llvm/llvm-project/pull/135659