; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 10. Linked List/cpp/Checking if Linked List is sorted.ll (Z5sortlv)

; 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"

%struct.node = type { i32, ptr }

@head = external dso_local global ptr, align 8

; 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 nounwind uwtable
define dso_local noundef i32 @_Z5sortlv() #1 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #2
  store i32 -2147483648, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #2
  %5 = load ptr, ptr @head, align 8, !tbaa !9
  store ptr %5, ptr %3, align 8, !tbaa !9
  br label %6

6:                                                ; preds = %16, %0
  %7 = load ptr, ptr %3, align 8, !tbaa !9
  %8 = icmp ne ptr %7, null
  br i1 %8, label %9, label %23

9:                                                ; preds = %6
  %10 = load ptr, ptr %3, align 8, !tbaa !9
  %11 = getelementptr inbounds %struct.node, ptr %10, i32 0, i32 0
  %12 = load i32, ptr %11, align 8, !tbaa !11
  %13 = load i32, ptr %2, align 4, !tbaa !5
  %14 = icmp slt i32 %12, %13
  br i1 %14, label %15, label %16

15:                                               ; preds = %9
  store i32 0, ptr %1, align 4
  store i32 1, ptr %4, align 4
  br label %24

16:                                               ; preds = %9
  %17 = load ptr, ptr %3, align 8, !tbaa !9
  %18 = getelementptr inbounds %struct.node, ptr %17, i32 0, i32 0
  %19 = load i32, ptr %18, align 8, !tbaa !11
  store i32 %19, ptr %2, align 4, !tbaa !5
  %20 = load ptr, ptr %3, align 8, !tbaa !9
  %21 = getelementptr inbounds %struct.node, ptr %20, i32 0, i32 1
  %22 = load ptr, ptr %21, align 8, !tbaa !13
  store ptr %22, ptr %3, align 8, !tbaa !9
  br label %6, !llvm.loop !14

23:                                               ; preds = %6
  store i32 1, ptr %1, align 4
  store i32 1, ptr %4, align 4
  br label %24

24:                                               ; preds = %23, %15
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #2
  %25 = load i32, ptr %1, align 4
  ret i32 %25
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { mustprogress nounwind 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 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = !{!12, !6, i64 0}
!12 = !{!"_ZTS4node", !6, i64 0, !10, i64 8}
!13 = !{!12, !10, i64 8}
!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"

@head = external dso_local local_unnamed_addr global ptr, align 8

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, inaccessiblemem: none) uwtable
define dso_local noundef range(i32 0, 2) i32 @_Z5sortlv() local_unnamed_addr #0 {
  %.08 = load ptr, ptr @head, align 8, !tbaa !5
  %.not9 = icmp eq ptr %.08, null
  br i1 %.not9, label %._crit_edge, label %.lr.ph

1:                                                ; preds = %.lr.ph
  %2 = getelementptr inbounds i8, ptr %.011, i64 8
  %.0 = load ptr, ptr %2, align 8, !tbaa !5
  %.not = icmp eq ptr %.0, null
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

.lr.ph:                                           ; preds = %0, %1
  %.011 = phi ptr [ %.0, %1 ], [ %.08, %0 ]
  %.0510 = phi i32 [ %3, %1 ], [ -2147483648, %0 ]
  %3 = load i32, ptr %.011, align 8, !tbaa !11
  %4 = icmp slt i32 %3, %.0510
  br i1 %4, label %._crit_edge, label %1

._crit_edge:                                      ; preds = %.lr.ph, %1, %0
  %.06 = phi i32 [ 1, %0 ], [ 1, %1 ], [ 0, %.lr.ph ]
  ret i32 %.06
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(read, inaccessiblemem: none) 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}
!13 = !{!"int", !7, i64 0}


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