[llvm] [AMDGPU] Convert flat scratch SS->SV in FI elimination (PR #166979)

[Diana Picus via llvm-commits]

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@@ -0,0 +1,630 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; REQUIRES: amdgpu-registered-target
+; Ensure we don't crash with: "Cannot scavenge register in FI elimination!"
+; RUN: llc < %s -verify-machineinstrs -O0 -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a | FileCheck %s --check-prefix=GFX90A
+; RUN: llc < %s -verify-machineinstrs -O0 -mtriple=amdgcn-amd-amdhsa -mcpu=gfx950 | FileCheck %s --check-prefix=GFX950
+
+target datalayout = "e-p:64:64-p1:64:64-p2:32:32-p3:32:32-p4:64:64-p5:32:32-p6:32:32-p7:160:256:256:32-p8:128:128-p9:192:256:256:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-S32-A5-G1-ni:7:8:9"
+target triple = "amdgcn-amd-amdhsa"
+
+define amdgpu_kernel void @issue155902(i64 %arg2, i64 %arg3, i64 %arg4, i64 %arg5, i64 %arg6, i64 %arg7, i64 %arg8, i64 %arg9, i64 %arg10, i64 %arg11, i64 %arg12, i64 %arg13, i64 %arg14, i64 %arg15, i64 %arg16, i64 %arg17, i64 %arg18, i64 %arg19, i64 %arg20, i64 %arg21, i64 %arg22, i64 %arg23, i64 %arg24, i64 %arg25, i64 %arg26, i64 %arg27, i64 %arg28, i64 %arg29, i64 %arg30, i64 %arg31, i64 %arg32, i64 %arg33, i64 %arg1, i64 %arg35, i64 %arg34, i64 %arg, i64 %arg38, i64 %arg39, i64 %arg40, i64 %arg41, i64 %arg42, i64 %arg43, i64 %arg44, i64 %arg37, i64 %arg46, i64 %arg47, i64 %arg48, i64 %arg49, i64 %arg45, i64 %arg36) {
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rovka wrote:

Please make it easy for people to figure out how many args there are (i.e. start at arg0 or arg1 and increment only by 1, without gaps and inversions).

https://github.com/llvm/llvm-project/pull/166979