; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C/Data-Structures/Queue (Queue_using_Stacks)

; 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"

@top1 = external dso_local global i32, align 4
@top2 = external dso_local global i32, align 4
@count = external dso_local global i32, align 4
@.str.11 = external hidden unnamed_addr constant [16 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

declare i32 @printf(ptr noundef, ...) #1

; Function Attrs: nounwind uwtable
declare dso_local void @push1(i32 noundef) #2

; Function Attrs: nounwind uwtable
declare dso_local void @push2(i32 noundef) #2

; Function Attrs: nounwind uwtable
declare dso_local i32 @pop1() #2

; Function Attrs: nounwind uwtable
declare dso_local i32 @pop2() #2

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

; Function Attrs: nounwind uwtable
define dso_local void @dequeue() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = load i32, ptr @top1, align 4, !tbaa !5
  %4 = icmp eq i32 %3, -1
  br i1 %4, label %5, label %10

5:                                                ; preds = %0
  %6 = load i32, ptr @top2, align 4, !tbaa !5
  %7 = icmp eq i32 %6, -1
  br i1 %7, label %8, label %10

8:                                                ; preds = %5
  %9 = call i32 (ptr, ...) @printf(ptr noundef @.str.11)
  br label %36

10:                                               ; preds = %5, %0
  call void @llvm.lifetime.start.p0(i64 4, ptr %1) #3
  store i32 0, ptr %1, align 4, !tbaa !5
  br label %11

11:                                               ; preds = %18, %10
  %12 = load i32, ptr %1, align 4, !tbaa !5
  %13 = load i32, ptr @count, align 4, !tbaa !5
  %14 = icmp sle i32 %12, %13
  br i1 %14, label %16, label %15

15:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 4, ptr %1) #3
  br label %21

16:                                               ; preds = %11
  %17 = call i32 @pop1()
  call void @push2(i32 noundef %17)
  br label %18

18:                                               ; preds = %16
  %19 = load i32, ptr %1, align 4, !tbaa !5
  %20 = add nsw i32 %19, 1
  store i32 %20, ptr %1, align 4, !tbaa !5
  br label %11, !llvm.loop !9

21:                                               ; preds = %15
  %22 = call i32 @pop2()
  %23 = load i32, ptr @count, align 4, !tbaa !5
  %24 = add nsw i32 %23, -1
  store i32 %24, ptr @count, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %25

25:                                               ; preds = %32, %21
  %26 = load i32, ptr %2, align 4, !tbaa !5
  %27 = load i32, ptr @count, align 4, !tbaa !5
  %28 = icmp sle i32 %26, %27
  br i1 %28, label %30, label %29

29:                                               ; preds = %25
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  br label %35

30:                                               ; preds = %25
  %31 = call i32 @pop2()
  call void @push1(i32 noundef %31)
  br label %32

32:                                               ; preds = %30
  %33 = load i32, ptr %2, align 4, !tbaa !5
  %34 = add nsw i32 %33, 1
  store i32 %34, ptr %2, align 4, !tbaa !5
  br label %25, !llvm.loop !11

35:                                               ; preds = %29
  br label %36

36:                                               ; preds = %35, %8
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { "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 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; 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"

@top1 = external dso_local local_unnamed_addr global i32, align 4
@top2 = external dso_local local_unnamed_addr global i32, align 4
@count = external dso_local local_unnamed_addr global i32, align 4
@.str.11 = external hidden unnamed_addr constant [16 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
declare dso_local void @push1(i32 noundef) local_unnamed_addr #1

; Function Attrs: nounwind uwtable
declare dso_local void @push2(i32 noundef) local_unnamed_addr #1

; Function Attrs: nounwind uwtable
declare dso_local i32 @pop1() local_unnamed_addr #1

; Function Attrs: nounwind uwtable
declare dso_local i32 @pop2() local_unnamed_addr #1

; Function Attrs: nounwind uwtable
define dso_local void @dequeue() local_unnamed_addr #1 {
  %1 = load i32, ptr @top1, align 4, !tbaa !5
  %2 = icmp eq i32 %1, -1
  %3 = load i32, ptr @top2, align 4
  %4 = icmp eq i32 %3, -1
  %or.cond = select i1 %2, i1 %4, i1 false
  br i1 %or.cond, label %6, label %.preheader

.preheader:                                       ; preds = %0
  %5 = load i32, ptr @count, align 4, !tbaa !5
  %.not7 = icmp slt i32 %5, 0
  br i1 %.not7, label %._crit_edge, label %.lr.ph

6:                                                ; preds = %0
  %7 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.11)
  br label %.loopexit

._crit_edge:                                      ; preds = %.lr.ph, %.preheader
  %8 = tail call i32 @pop2()
  %9 = load i32, ptr @count, align 4, !tbaa !5
  %10 = add nsw i32 %9, -1
  store i32 %10, ptr @count, align 4, !tbaa !5
  %.not69 = icmp slt i32 %9, 1
  br i1 %.not69, label %.loopexit, label %.lr.ph12

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %.058 = phi i32 [ %12, %.lr.ph ], [ 0, %.preheader ]
  %11 = tail call i32 @pop1()
  tail call void @push2(i32 noundef %11)
  %12 = add nuw nsw i32 %.058, 1
  %13 = load i32, ptr @count, align 4, !tbaa !5
  %.not.not = icmp slt i32 %.058, %13
  br i1 %.not.not, label %.lr.ph, label %._crit_edge, !llvm.loop !9

.lr.ph12:                                         ; preds = %._crit_edge, %.lr.ph12
  %.010 = phi i32 [ %15, %.lr.ph12 ], [ 0, %._crit_edge ]
  %14 = tail call i32 @pop2()
  tail call void @push1(i32 noundef %14)
  %15 = add nuw nsw i32 %.010, 1
  %16 = load i32, ptr @count, align 4, !tbaa !5
  %.not6.not = icmp slt i32 %.010, %16
  br i1 %.not6.not, label %.lr.ph12, label %.loopexit, !llvm.loop !11

.loopexit:                                        ; preds = %.lr.ph12, %._crit_edge, %6
  ret void
}

attributes #0 = { nofree nounwind "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 = { 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" }

!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/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


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