[llvm] [AMDGPU] Modify Dyn Alloca test case to account for Machine-Verifier behavior (PR #120393)

[via llvm-commits]

https://github.com/easyonaadit created https://github.com/llvm/llvm-project/pull/120393

Machine-Verifier crashes in kernel functions, 
but fails gracefully in device functions.

This is due to the buffer resource descriptor selected
during G-ISEL, before the fallback path. 
Kernel functions select `$private_rsrc_reg` 
where machine-verifier complains: `$private_rsrc_reg is not a SReg_128 register.`
While device functions use `$sgpr0_sgpr1_sgpr2_sgpr3`.

Modifying test case to capture both behaviors, this is related to https://github.com/llvm/llvm-project/pull/120063


>From 7e44fbac4eff5ef09f7c5bc79a03253611a548e6 Mon Sep 17 00:00:00 2001
From: easyonaadit <aaditya.alokdeshpande at amd.com>
Date: Wed, 18 Dec 2024 14:42:36 +0530
Subject: [PATCH] Modifying test case to capture machine verifier errors

---
 .../GlobalISel/dynamic-alloca-divergent.ll    | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/llvm/test/CodeGen/AMDGPU/GlobalISel/dynamic-alloca-divergent.ll b/llvm/test/CodeGen/AMDGPU/GlobalISel/dynamic-alloca-divergent.ll
index 5dae7885f6bfb1..e0f22bc32b63c8 100644
--- a/llvm/test/CodeGen/AMDGPU/GlobalISel/dynamic-alloca-divergent.ll
+++ b/llvm/test/CodeGen/AMDGPU/GlobalISel/dynamic-alloca-divergent.ll
@@ -1,25 +1,30 @@
-; RUN: not llc -global-isel -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -global-isel-abort=2 -pass-remarks-missed="gisel.*" -verify-machineinstrs -o /dev/null 2>&1 %s | FileCheck -check-prefix=ERR %s
+; RUN: not --crash llc -global-isel -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -global-isel-abort=2 -pass-remarks-missed="gisel.*" -verify-machineinstrs -o /dev/null 2>&1 %s | FileCheck -check-prefix=ERR_KERNEL %s
+; RUN: not llc -global-isel -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -global-isel-abort=2 -pass-remarks-missed="gisel.*" -o /dev/null 2>&1 %s | FileCheck -check-prefix=ERR %s
+
+; ERR_KERNEL: remark: <unknown>:0:0: cannot select: %{{[0-9]+}}:sreg_32(p5) = G_DYN_STACKALLOC %{{[0-9]+}}:vgpr(s32), 1 (in function: kernel_dynamic_stackalloc_vgpr_align4)
+; ERR_KERNEL-NEXT: warning: Instruction selection used fallback path for kernel_dynamic_stackalloc_vgpr_align4
+; ERR_KERNEL-NEXT: error: <unknown>:0:0: in function kernel_dynamic_stackalloc_vgpr_align4 void (ptr addrspace(1)): unsupported dynamic alloca
 
 ; ERR: remark: <unknown>:0:0: cannot select: %{{[0-9]+}}:sreg_32(p5) = G_DYN_STACKALLOC %{{[0-9]+}}:vgpr(s32), 1 (in function: kernel_dynamic_stackalloc_vgpr_align4)
 ; ERR-NEXT: warning: Instruction selection used fallback path for kernel_dynamic_stackalloc_vgpr_align4
 ; ERR-NEXT: error: <unknown>:0:0: in function kernel_dynamic_stackalloc_vgpr_align4 void (ptr addrspace(1)): unsupported dynamic alloca
 
-; ERR: remark: <unknown>:0:0: cannot select: %{{[0-9]+}}:sreg_32(p5) = G_DYN_STACKALLOC %{{[0-9]+}}:vgpr(s32), 1 (in function: func_dynamic_stackalloc_vgpr_align4)
-; ERR-NEXT: warning: Instruction selection used fallback path for func_dynamic_stackalloc_vgpr_align4
-; ERR-NEXT: error: <unknown>:0:0: in function func_dynamic_stackalloc_vgpr_align4 void (i32): unsupported dynamic alloca
-
 define amdgpu_kernel void @kernel_dynamic_stackalloc_vgpr_align4(ptr addrspace(1) %ptr) {
   %id = call i32 @llvm.amdgcn.workitem.id.x()
   %gep = getelementptr i32, ptr addrspace(1) %ptr, i32 %id
   %n = load i32, ptr addrspace(1) %gep
   %alloca = alloca i32, i32 %n, align 4, addrspace(5)
-  store volatile ptr addrspace(5) %alloca, ptr addrspace(1) undef
+  store volatile i32 5, ptr addrspace(5) %alloca
   ret void
 }
 
+; ERR: remark: <unknown>:0:0: cannot select: %{{[0-9]+}}:sreg_32(p5) = G_DYN_STACKALLOC %{{[0-9]+}}:vgpr(s32), 1 (in function: func_dynamic_stackalloc_vgpr_align4)
+; ERR-NEXT: warning: Instruction selection used fallback path for func_dynamic_stackalloc_vgpr_align4
+; ERR-NEXT: error: <unknown>:0:0: in function func_dynamic_stackalloc_vgpr_align4 void (i32): unsupported dynamic alloca
+
 define void @func_dynamic_stackalloc_vgpr_align4(i32 %n) {
   %alloca = alloca i32, i32 %n, align 4, addrspace(5)
-  store volatile ptr addrspace(5) %alloca, ptr addrspace(1) undef
+  store volatile i32 10, ptr addrspace(5) %alloca
   ret void
 }