[llvm] AMDGPU: Add tests for atomics with AGPR operands (PR #155820)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,237 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx90a -verify-machineinstrs < %s | FileCheck %s
+
+define void @ds_atomic_cmpxchg_i32_ret_av_av__av(ptr addrspace(3) %ptr) #0 {
+; CHECK-LABEL: ds_atomic_cmpxchg_i32_ret_av_av__av:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    ;;#ASMSTART
+; CHECK-NEXT:    ; def v1
+; CHECK-NEXT:    ;;#ASMEND
+; CHECK-NEXT:    ;;#ASMSTART
+; CHECK-NEXT:    ; def v2
+; CHECK-NEXT:    ;;#ASMEND
+; CHECK-NEXT:    ds_cmpst_rtn_b32 v0, v0, v1, v2 offset:40
+; CHECK-NEXT:    s_waitcnt lgkmcnt(0)
+; CHECK-NEXT:    ;;#ASMSTART
+; CHECK-NEXT:    ; use v0
+; CHECK-NEXT:    ;;#ASMEND
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %gep.0 = getelementptr inbounds [512 x i32], ptr addrspace(3) %ptr, i32 0, i32 10
+  %data0 = call i32 asm "; def $0", "=^VA"()
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arsenm wrote:

Uses AV class 

https://github.com/llvm/llvm-project/pull/155820