; LLVM IR from TheAlgorithms/C-Plus-Plus :: data_structures/doubly_linked_list.ll (ZN18double_linked_list6searchEi)

; Unoptimized IR (clang -disable-llvm-passes):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%struct.node = type { i32, ptr, ptr }

@start = external dso_local global ptr, align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [7 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [11 x i8], align 1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress uwtable
define dso_local void @_ZN18double_linked_list6searchEi(ptr noundef nonnull align 1 dereferenceable(1) %0, i32 noundef %1) #1 align 2 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  %7 = load ptr, ptr %3, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %8 = load ptr, ptr @start, align 8, !tbaa !5
  store ptr %8, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  store i32 0, ptr %6, align 4, !tbaa !9
  br label %9

9:                                                ; preds = %20, %2
  %10 = load ptr, ptr %5, align 8, !tbaa !5
  %11 = icmp ne ptr %10, null
  br i1 %11, label %12, label %24

12:                                               ; preds = %9
  %13 = load ptr, ptr %5, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.node, ptr %13, i32 0, i32 0
  %15 = load i32, ptr %14, align 8, !tbaa !11
  %16 = load i32, ptr %4, align 4, !tbaa !9
  %17 = icmp eq i32 %15, %16
  br i1 %17, label %18, label %20

18:                                               ; preds = %12
  %19 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str)
  store i32 1, ptr %6, align 4, !tbaa !9
  br label %24

20:                                               ; preds = %12
  %21 = load ptr, ptr %5, align 8, !tbaa !5
  %22 = getelementptr inbounds %struct.node, ptr %21, i32 0, i32 2
  %23 = load ptr, ptr %22, align 8, !tbaa !13
  store ptr %23, ptr %5, align 8, !tbaa !5
  br label %9, !llvm.loop !14

24:                                               ; preds = %18, %9
  %25 = load i32, ptr %6, align 4, !tbaa !9
  %26 = icmp eq i32 %25, 0
  br i1 %26, label %27, label %29

27:                                               ; preds = %24
  %28 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str.1)
  br label %29

29:                                               ; preds = %27, %24
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  ret void
}

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #2 = { inlinehint mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #3 = { nounwind }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"_ZTS4node", !10, i64 0, !6, i64 8, !6, i64 16}
!13 = !{!12, !6, i64 16}
!14 = distinct !{!14, !15}
!15 = !{!"llvm.loop.mustprogress"}


; Optimized IR (opt -passes='default<O3>'):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }

@start = external dso_local local_unnamed_addr global ptr, align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [7 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [11 x i8], align 1

; Function Attrs: mustprogress uwtable
define dso_local void @_ZN18double_linked_list6searchEi(ptr nocapture noundef nonnull readnone align 1 dereferenceable(1) %0, i32 noundef %1) local_unnamed_addr #0 align 2 {
  %.056 = load ptr, ptr @start, align 8, !tbaa !5
  %.not7 = icmp eq ptr %.056, null
  br i1 %.not7, label %.critedge, label %.lr.ph

3:                                                ; preds = %.lr.ph
  %4 = getelementptr inbounds i8, ptr %.058, i64 16
  %.05 = load ptr, ptr %4, align 8, !tbaa !5
  %.not = icmp eq ptr %.05, null
  br i1 %.not, label %.critedge, label %.lr.ph, !llvm.loop !9

.lr.ph:                                           ; preds = %2, %3
  %.058 = phi ptr [ %.05, %3 ], [ %.056, %2 ]
  %5 = load i32, ptr %.058, align 8, !tbaa !11
  %6 = icmp eq i32 %5, %1
  br i1 %6, label %.critedge, label %3

.critedge:                                        ; preds = %3, %.lr.ph, %2
  %.str.sink = phi ptr [ @.str.1, %2 ], [ @.str, %.lr.ph ], [ @.str.1, %3 ]
  %7 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull %.str.sink)
  ret void
}

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #1

attributes #0 = { mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { inlinehint mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!12, !13, i64 0}
!12 = !{!"_ZTS4node", !13, i64 0, !6, i64 8, !6, i64 16}
!13 = !{!"int", !7, i64 0}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass