Added small unit test for symbol checking

Author: vyom1611

llvm/test/CodeGen/NVPTX/nvptx-debug-symbol-name.ll

@@ -0,0 +1,42 @@
+; RUN: llc -mtriple=nvptx64-nvidia-cuda -mcpu=sm_86 < %s | FileCheck %s
+
+; CHECK: .global .align 1 .b8 __func___$__Z10foo_kernelv
+
+; ModuleID = 'test_module'
+source_filename = "test_module.cu"
+target datalayout = "e-i64:64-i128:128-v16:16-v32:32-n16:32:64"
+target triple = "nvptx64-nvidia-cuda"
+
+@__func__._Z10foo_kernelv = private unnamed_addr constant [11 x i8] c"foo_kernel\00", align 1, !dbg !0
+
+define dso_local void @_Z10foo_kernelv() #0 !dbg !20 {
+entry:
+  call void @_Z6escapePKc(ptr noundef @__func__._Z10foo_kernelv) #2, !dbg !23
+  ret void, !dbg !24
+}
+
+declare dso_local void @_Z6escapePKc(ptr noundef)
+
+attributes #0 = { noinline nounwind optnone "target-cpu"="sm_86" }
+attributes #1 = { nounwind }
+attributes #2 = { nounwind }
+
+!llvm.dbg.cu = !{!14}
+!llvm.ident = !{!18}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(scope: null, file: !2, name: "__func__", linkageName: "__func__._Z10foo_kernelv", line: 6, type: !3, isLocal: true, isDefinition: true)
+!2 = !DIFile(filename: "test_module.cu", directory: "/")
+!3 = !DICompositeType(tag: DW_TAG_array_type, baseType: !4, size: 88, elements: !6)
+!4 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !5)
+!5 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
+!6 = !{!7}
+!7 = !DISubrange(count: 11)
+!14 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !2, producer: "clang version 20.0.0git", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !16, nameTableKind: None)
+!16 = !{!0}
+!18 = !{!"clang version 20.0.0git"}
+!20 = distinct !DISubprogram(name: "foo_kernel", linkageName: "_Z10foo_kernelv", scope: !2, file: !2, line: 4, type: !21, scopeLine: 5, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !14)
+!21 = !DISubroutineType(types: !22)
+!22 = !{null}
+!23 = !DILocation(line: 6, column: 5, scope: !20)
+!24 = !DILocation(line: 7, column: 1, scope: !20)