[llvm] [AMDGPU] Restore the default rounding mode before calls and returns (PR #222247)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,120 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgcn -mcpu=gfx900 < %s | FileCheck %s
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arsenm wrote:

```suggestion
; RUN: llc -mtriple=amdgpu9.00 < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/222247