[llvm] AMDGPU: Add baseline test for nofpclass on call results (PR #167263)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,199 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck %s
+
+; Check that nofpclass attributes on call returns are used in
+; selectiondag.
+
+define internal float @func_f32(ptr addrspace(1) %ptr) {
+; CHECK-LABEL: func_f32:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    global_load_dword v0, v[0:1], off glc
+; CHECK-NEXT:    s_waitcnt vmcnt(0)
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %ld = load volatile float, ptr addrspace(1) %ptr
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arsenm wrote:

Just provide a value. Attributor would be able to fold these into one value if it was a return of constant, though we happen to not run it in codegen anymore 

https://github.com/llvm/llvm-project/pull/167263