[AnnotationRemarks] Add test for annotation remarks with dbg locations.

The test illustrates that we not pick the debug location from the
function directly. This will be fixed in a follow-up patch.

Author: fhahn

llvm/test/Transforms/Util/annotation-remarks-dbg-info.ll

@@ -0,0 +1,77 @@
+; RUN: opt -annotation-remarks -pass-remarks-missed='annotation-remarks' -disable-output -pass-remarks-output=%t.opt.yaml %s
+; RUN: FileCheck --input-file=%t.opt.yaml %s
+; RUN: opt -passes='annotation-remarks' -pass-remarks-missed='annotation-remarks' -disable-output -pass-remarks-output=%t.opt.yaml %s
+; RUN: FileCheck --input-file=%t.opt.yaml %s
+
+; Make sure a suitable location is used for the function start when emitting
+; the annotation summary remarks.
+
+; CHECK:      --- !Analysis
+; CHECK-NEXT: Pass:            annotation-remarks
+; CHECK-NEXT: Name:            AnnotationSummary
+; CHECK-NEXT: DebugLoc: { File: test.c, Line: 400, Column: 3 }
+; CHECK-NEXT: Function:        test1
+; CHECK-NEXT: Args:
+; CHECK-NEXT:   - String:          'Annotated '
+; CHECK-NEXT:   - count:           '4'
+; CHECK-NEXT:   - String:          ' instructions with '
+; CHECK-NEXT:   - type:            _remarks1
+; CHECK-NEXT: ...
+; CHECK-NEXT: --- !Analysis
+; CHECK-NEXT: Pass:            annotation-remarks
+; CHECK-NEXT: Name:            AnnotationSummary
+; CHECK-NEXT: DebugLoc: { File: test.c, Line: 400, Column: 3 }
+; CHECK-NEXT: Function:        test1
+; CHECK-NEXT: Args:
+; CHECK-NEXT:   - String:          'Annotated '
+; CHECK-NEXT:   - count:           '3'
+; CHECK-NEXT:   - String:          ' instructions with '
+; CHECK-NEXT:   - type:            _remarks2
+; CHECK-NEXT: ...
+; CHECK-NEXT: --- !Analysis
+; CHECK-NEXT: Pass:            annotation-remarks
+; CHECK-NEXT: Name:            AnnotationSummary
+; CHECK-NEXT: Function:        test2
+; CHECK-NEXT: Args:
+; CHECK-NEXT:   - String:          'Annotated '
+; CHECK-NEXT:   - count:           '2'
+; CHECK-NEXT:   - String:          ' instructions with '
+; CHECK-NEXT:   - type:            _remarks1
+; CHECK-NEXT: ...
+
+define void @test1(float* %a) !dbg !7 {
+entry:
+  %a.addr = alloca float*, align 8, !dbg !16, !annotation !5
+  store float* null, float** %a.addr, align 8, !annotation !6
+  store float* %a, float** %a.addr, align 8, !annotation !5
+  ret void, !annotation !5
+}
+
+define void @test2(float* %a) !dbg !17 {
+entry:
+  %a.addr = alloca float*, align 8, !annotation !6
+  ret void, !dbg !18, !annotation !6
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "test.c", directory: "/test")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{!"_remarks1", !"_remarks2"}
+!6 = !{!"_remarks1"}
+!7 = distinct !DISubprogram(name: "test1", scope: !1, file: !1, line: 11, type: !8, scopeLine: 10, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !14)
+!8 = !DISubroutineType(types: !9)
+!9 = !{null, !10, !10, !13}
+!10 = !DIDerivedType(tag: DW_TAG_restrict_type, baseType: !11)
+!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 32, align: 32)
+!12 = !DIBasicType(name: "float", size: 32, align: 32, encoding: DW_ATE_float)
+!13 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!14 = !{!15}
+!15 = !DILocalVariable(name: "a", arg: 1, scope: !7, file: !1, line: 1, type: !10)
+!16 = !DILocation(line: 400, column: 3, scope: !7)
+!17 = distinct !DISubprogram(name: "test2", scope: !1, file: !1, line: 21, type: !8, scopeLine: 20, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !14)
+!18 = !DILocation(line: 200, column: 3, scope: !17)