; RUN: opt %s -S -passes=instcombine -o - | FileCheck %s

;; $ cat test.cpp
;; class a {
;;   float b;
;; };
;; class c {
;; public:
;;   a d();
;; };
;; class e {
;; public:
;;   c &f();
;; };
;; class g {
;; public:
;;   void h(a &);
;; };
;; class j {
;;   g k;
;;   e l;
;;   e m;
;;   bool n;
;;   void o();
;; };
;; void j::o() {
;;   int i;
;;   a p;
;;   i = 0;
;;   for (; i < 3; i++)
;;     if (n)
;;       p = l.f().d();
;;     else
;;       p = m.f().d();
;;   k.h(p);
;; }
;;
;; Generated by grabbing IR before instcombine in:
;; $ clang++ -O2 -g -c test.cpp -Xclang -fexperimental-assignment-tracking

;; Before instcombine runs we have an unrolled loop (3 iterations). Each
;; unrolled section is an if-diamond with a store in if.then and if.else
;; block. The "same" stores in each unrolled section have the same
;; DIAssignID. Instcombine is going to sink the stores from if.then and if.else
;; into if.end for each unrolled section. This involves merging the DIAssignID
;; of the two stores. Check that each merge updates all linked instructions
;; with the same DIAssignID attachments too.

; CHECK: if.then:
; CHECK: call void @llvm.dbg.assign(metadata float %call2, metadata ![[var:[0-9]+]], metadata !DIExpression(), metadata ![[id:[0-9]+]], metadata ptr %p, metadata !DIExpression()), !dbg
; CHECK: br label %for.inc

; CHECK: if.else:
; CHECK: call void @llvm.dbg.assign(metadata float %call5, metadata ![[var]], metadata !DIExpression(), metadata ![[id]], metadata ptr %p, metadata !DIExpression()), !dbg
; CHECK: br label %for.inc

; CHECK: for.inc:
; CHECK-NEXT: %storemerge = phi float [ %call2, %if.then ], [ %call5, %if.else ]
; CHECK-NEXT: store float %storemerge, ptr %p, align 4{{.+}}!DIAssignID ![[id]]

; CHECK: if.then.1:
; CHECK: call void @llvm.dbg.assign(metadata float %call2.1, metadata ![[var]], metadata !DIExpression(), metadata ![[id]], metadata ptr %p, metadata !DIExpression()), !dbg
; CHECK: br label %for.inc.1

; CHECK: if.else.1:
; CHECK: call void @llvm.dbg.assign(metadata float %call5.1, metadata ![[var]], metadata !DIExpression(), metadata ![[id]], metadata ptr %p, metadata !DIExpression()), !dbg
; CHECK: br label %for.inc.1

; CHECK: for.inc.1:
; CHECK-NEXT: %storemerge1 = phi float [ %call2.1, %if.then.1 ], [ %call5.1, %if.else.1 ]
; CHECK-NEXT: store float %storemerge1, ptr %p, align 4{{.+}}!DIAssignID ![[id]]

; CHECK: if.then.2:
; CHECK: call void @llvm.dbg.assign(metadata float %call2.2, metadata ![[var]], metadata !DIExpression(), metadata ![[id]], metadata ptr %p, metadata !DIExpression()), !dbg
; CHECK: br label %for.inc.2

; CHECK: if.else.2:
; CHECK: call void @llvm.dbg.assign(metadata float %call5.2, metadata ![[var]], metadata !DIExpression(), metadata ![[id]], metadata ptr %p, metadata !DIExpression()), !dbg
; CHECK:  br label %for.inc.2

; CHECK: for.inc.2:
; CHECK-NEXT: %storemerge2 = phi float [ %call2.2, %if.then.2 ], [ %call5.2, %if.else.2 ]
; CHECK-NEXT: store float %storemerge2, ptr %p, align 4{{.+}}!DIAssignID ![[id]]

%class.j = type { %class.g, %class.e, %class.e, i8 }
%class.g = type { i8 }
%class.e = type { i8 }
%class.a = type { float }
%class.c = type { i8 }

; Function Attrs: uwtable
define dso_local void @_ZN1j1oEv(ptr %this) local_unnamed_addr #0 align 2 !dbg !7 {
entry:
  %p = alloca %class.a, align 4, !DIAssignID !49
  call void @llvm.dbg.assign(metadata i1 undef, metadata !48, metadata !DIExpression(), metadata !49, metadata ptr %p, metadata !DIExpression()), !dbg !50
  %0 = bitcast ptr %p to ptr, !dbg !51
  call void @llvm.lifetime.start.p0i8(i64 4, ptr nonnull %0) #4, !dbg !51
  %n = getelementptr inbounds %class.j, ptr %this, i64 0, i32 3
  %l = getelementptr inbounds %class.j, ptr %this, i64 0, i32 1
  %ref.tmp.sroa.0.0..sroa_idx = getelementptr inbounds %class.a, ptr %p, i64 0, i32 0
  %m = getelementptr inbounds %class.j, ptr %this, i64 0, i32 2
  %1 = load i8, ptr %n, align 1, !dbg !52
  %tobool.not = icmp eq i8 %1, 0, !dbg !52
  br i1 %tobool.not, label %if.else, label %if.then, !dbg !64

if.then:                                          ; preds = %entry
  %call = tail call nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr nonnull %l), !dbg !65
  %call2 = tail call float @_ZN1c1dEv(ptr nonnull %call), !dbg !66
  store float %call2, ptr %ref.tmp.sroa.0.0..sroa_idx, align 4, !dbg !67, !DIAssignID !71
  call void @llvm.dbg.assign(metadata float %call2, metadata !48, metadata !DIExpression(), metadata !71, metadata ptr %ref.tmp.sroa.0.0..sroa_idx, metadata !DIExpression()), !dbg !50
  br label %for.inc, !dbg !72

if.else:                                          ; preds = %entry
  %call4 = tail call nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr nonnull %m), !dbg !73
  %call5 = tail call float @_ZN1c1dEv(ptr nonnull %call4), !dbg !74
  store float %call5, ptr %ref.tmp.sroa.0.0..sroa_idx, align 4, !dbg !75, !DIAssignID !76
  call void @llvm.dbg.assign(metadata float %call5, metadata !48, metadata !DIExpression(), metadata !76, metadata ptr %ref.tmp.sroa.0.0..sroa_idx, metadata !DIExpression()), !dbg !50
  br label %for.inc

for.inc:                                          ; preds = %if.then, %if.else
  %2 = load i8, ptr %n, align 1, !dbg !52
  %tobool.not.1 = icmp eq i8 %2, 0, !dbg !52
  br i1 %tobool.not.1, label %if.else.1, label %if.then.1, !dbg !64

if.then.1:                                        ; preds = %for.inc
  %call.1 = tail call nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr nonnull %l), !dbg !65
  %call2.1 = tail call float @_ZN1c1dEv(ptr nonnull %call.1), !dbg !66
  store float %call2.1, ptr %ref.tmp.sroa.0.0..sroa_idx, align 4, !dbg !67, !DIAssignID !71
  call void @llvm.dbg.assign(metadata float %call2.1, metadata !48, metadata !DIExpression(), metadata !71, metadata ptr %ref.tmp.sroa.0.0..sroa_idx, metadata !DIExpression()), !dbg !50
  br label %for.inc.1, !dbg !72

if.else.1:                                        ; preds = %for.inc
  %call4.1 = tail call nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr nonnull %m), !dbg !73
  %call5.1 = tail call float @_ZN1c1dEv(ptr nonnull %call4.1), !dbg !74
  store float %call5.1, ptr %ref.tmp.sroa.0.0..sroa_idx, align 4, !dbg !75, !DIAssignID !76
  call void @llvm.dbg.assign(metadata float %call5.1, metadata !48, metadata !DIExpression(), metadata !76, metadata ptr %ref.tmp.sroa.0.0..sroa_idx, metadata !DIExpression()), !dbg !50
  br label %for.inc.1

for.inc.1:                                        ; preds = %if.else.1, %if.then.1
  %3 = load i8, ptr %n, align 1, !dbg !52
  %tobool.not.2 = icmp eq i8 %3, 0, !dbg !52
  br i1 %tobool.not.2, label %if.else.2, label %if.then.2, !dbg !64

if.then.2:                                        ; preds = %for.inc.1
  %call.2 = tail call nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr nonnull %l), !dbg !65
  %call2.2 = tail call float @_ZN1c1dEv(ptr nonnull %call.2), !dbg !66
  store float %call2.2, ptr %ref.tmp.sroa.0.0..sroa_idx, align 4, !dbg !67, !DIAssignID !71
  call void @llvm.dbg.assign(metadata float %call2.2, metadata !48, metadata !DIExpression(), metadata !71, metadata ptr %ref.tmp.sroa.0.0..sroa_idx, metadata !DIExpression()), !dbg !50
  br label %for.inc.2, !dbg !72

if.else.2:                                        ; preds = %for.inc.1
  %call4.2 = tail call nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr nonnull %m), !dbg !73
  %call5.2 = tail call float @_ZN1c1dEv(ptr nonnull %call4.2), !dbg !74
  store float %call5.2, ptr %ref.tmp.sroa.0.0..sroa_idx, align 4, !dbg !75, !DIAssignID !76
  call void @llvm.dbg.assign(metadata float %call5.2, metadata !48, metadata !DIExpression(), metadata !76, metadata ptr %ref.tmp.sroa.0.0..sroa_idx, metadata !DIExpression()), !dbg !50
  br label %for.inc.2

for.inc.2:                                        ; preds = %if.else.2, %if.then.2
  %k = getelementptr inbounds %class.j, ptr %this, i64 0, i32 0, !dbg !77
  call void @_ZN1g1hER1a(ptr %k, ptr nonnull align 4 dereferenceable(4) %p), !dbg !78
  call void @llvm.lifetime.end.p0i8(i64 4, ptr nonnull %0) #4, !dbg !79
  ret void, !dbg !79
}

; Function Attrs: argmemonly nofree nosync nounwind willreturn
declare void @llvm.lifetime.start.p0i8(i64 immarg, ptr nocapture) #1

declare dso_local nonnull align 1 dereferenceable(1) ptr @_ZN1e1fEv(ptr) local_unnamed_addr #2

declare dso_local float @_ZN1c1dEv(ptr) local_unnamed_addr #2

; Function Attrs: argmemonly nofree nosync nounwind willreturn
declare void @llvm.lifetime.end.p0i8(i64 immarg, ptr nocapture) #1

declare dso_local void @_ZN1g1hER1a(ptr, ptr nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

; Function Attrs: nofree nosync nounwind readnone speculatable willreturn
declare void @llvm.dbg.assign(metadata, metadata, metadata, metadata, metadata, metadata) #3

!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4, !5, !1000}
!llvm.ident = !{!6}

!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 12.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None)
!1 = !DIFile(filename: "test.cpp", directory: "/")
!2 = !{}
!3 = !{i32 7, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = !{i32 1, !"wchar_size", i32 4}
!6 = !{!"clang version 12.0.0"}
!7 = distinct !DISubprogram(name: "o", linkageName: "_ZN1j1oEv", scope: !8, file: !1, line: 23, type: !40, scopeLine: 23, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, declaration: !39, retainedNodes: !43)
!8 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "j", file: !1, line: 16, size: 32, flags: DIFlagTypePassByValue, elements: !9, identifier: "_ZTS1j")
!9 = !{!10, !22, !36, !37, !39}
!10 = !DIDerivedType(tag: DW_TAG_member, name: "k", scope: !8, file: !1, line: 17, baseType: !11, size: 8)
!11 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "g", file: !1, line: 12, size: 8, flags: DIFlagTypePassByValue, elements: !12, identifier: "_ZTS1g")
!12 = !{!13}
!13 = !DISubprogram(name: "h", linkageName: "_ZN1g1hER1a", scope: !11, file: !1, line: 14, type: !14, scopeLine: 14, flags: DIFlagPublic | DIFlagPrototyped, spFlags: DISPFlagOptimized)
!14 = !DISubroutineType(types: !15)
!15 = !{null, !16, !17}
!16 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !11, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
!17 = !DIDerivedType(tag: DW_TAG_reference_type, baseType: !18, size: 64)
!18 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "a", file: !1, line: 1, size: 32, flags: DIFlagTypePassByValue, elements: !19, identifier: "_ZTS1a")
!19 = !{!20}
!20 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !18, file: !1, line: 2, baseType: !21, size: 32)
!21 = !DIBasicType(name: "float", size: 32, encoding: DW_ATE_float)
!22 = !DIDerivedType(tag: DW_TAG_member, name: "l", scope: !8, file: !1, line: 18, baseType: !23, size: 8, offset: 8)
!23 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "e", file: !1, line: 8, size: 8, flags: DIFlagTypePassByValue, elements: !24, identifier: "_ZTS1e")
!24 = !{!25}
!25 = !DISubprogram(name: "f", linkageName: "_ZN1e1fEv", scope: !23, file: !1, line: 10, type: !26, scopeLine: 10, flags: DIFlagPublic | DIFlagPrototyped, spFlags: DISPFlagOptimized)
!26 = !DISubroutineType(types: !27)
!27 = !{!28, !35}
!28 = !DIDerivedType(tag: DW_TAG_reference_type, baseType: !29, size: 64)
!29 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "c", file: !1, line: 4, size: 8, flags: DIFlagTypePassByValue, elements: !30, identifier: "_ZTS1c")
!30 = !{!31}
!31 = !DISubprogram(name: "d", linkageName: "_ZN1c1dEv", scope: !29, file: !1, line: 6, type: !32, scopeLine: 6, flags: DIFlagPublic | DIFlagPrototyped, spFlags: DISPFlagOptimized)
!32 = !DISubroutineType(types: !33)
!33 = !{!18, !34}
!34 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !29, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
!35 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !23, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
!36 = !DIDerivedType(tag: DW_TAG_member, name: "m", scope: !8, file: !1, line: 19, baseType: !23, size: 8, offset: 16)
!37 = !DIDerivedType(tag: DW_TAG_member, name: "n", scope: !8, file: !1, line: 20, baseType: !38, size: 8, offset: 24)
!38 = !DIBasicType(name: "bool", size: 8, encoding: DW_ATE_boolean)
!39 = !DISubprogram(name: "o", linkageName: "_ZN1j1oEv", scope: !8, file: !1, line: 21, type: !40, scopeLine: 21, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized)
!40 = !DISubroutineType(types: !41)
!41 = !{null, !42}
!42 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !8, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
!43 = !{!44, !46, !48}
!44 = !DILocalVariable(name: "this", arg: 1, scope: !7, type: !45, flags: DIFlagArtificial | DIFlagObjectPointer)
!45 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !8, size: 64)
!46 = !DILocalVariable(name: "i", scope: !7, file: !1, line: 24, type: !47)
!47 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!48 = !DILocalVariable(name: "p", scope: !7, file: !1, line: 25, type: !18)
!49 = distinct !DIAssignID()
!50 = !DILocation(line: 0, scope: !7)
!51 = !DILocation(line: 25, column: 3, scope: !7)
!52 = !DILocation(line: 28, column: 9, scope: !53)
!53 = distinct !DILexicalBlock(scope: !54, file: !1, line: 28, column: 9)
!54 = distinct !DILexicalBlock(scope: !55, file: !1, line: 27, column: 3)
!55 = distinct !DILexicalBlock(scope: !7, file: !1, line: 27, column: 3)
!64 = !DILocation(line: 28, column: 9, scope: !54)
!65 = !DILocation(line: 29, column: 13, scope: !53)
!66 = !DILocation(line: 29, column: 17, scope: !53)
!67 = !DILocation(line: 29, column: 9, scope: !53)
!71 = distinct !DIAssignID()
!72 = !DILocation(line: 29, column: 7, scope: !53)
!73 = !DILocation(line: 31, column: 13, scope: !53)
!74 = !DILocation(line: 31, column: 17, scope: !53)
!75 = !DILocation(line: 31, column: 9, scope: !53)
!76 = distinct !DIAssignID()
!77 = !DILocation(line: 32, column: 3, scope: !7)
!78 = !DILocation(line: 32, column: 5, scope: !7)
!79 = !DILocation(line: 33, column: 1, scope: !7)
!1000 = !{i32 7, !"debug-info-assignment-tracking", i1 true}