; LLVM IR from UtkarshPathrabe/Competitive-Coding :: Model Algorithms/Dynamic Programming/Fibonacci Numbers/Fibonacci Using Recursion.l_07627ca0 (Reci)

; 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"

@fib = external dso_local global [100 x i64], align 16

; Function Attrs: mustprogress uwtable
define dso_local noundef i64 @_Z13Fibonacci_Reci(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  %3 = load i32, ptr %2, align 4, !tbaa !5
  %4 = sext i32 %3 to i64
  %5 = getelementptr inbounds [100 x i64], ptr @fib, i64 0, i64 %4
  %6 = load i64, ptr %5, align 8, !tbaa !9
  %7 = icmp slt i64 %6, 0
  br i1 %7, label %8, label %35

8:                                                ; preds = %1
  %9 = load i32, ptr %2, align 4, !tbaa !5
  %10 = icmp eq i32 %9, 0
  br i1 %10, label %11, label %15

11:                                               ; preds = %8
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds [100 x i64], ptr @fib, i64 0, i64 %13
  store i64 0, ptr %14, align 8, !tbaa !9
  br label %34

15:                                               ; preds = %8
  %16 = load i32, ptr %2, align 4, !tbaa !5
  %17 = icmp eq i32 %16, 1
  br i1 %17, label %18, label %22

18:                                               ; preds = %15
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [100 x i64], ptr @fib, i64 0, i64 %20
  store i64 1, ptr %21, align 8, !tbaa !9
  br label %33

22:                                               ; preds = %15
  %23 = load i32, ptr %2, align 4, !tbaa !5
  %24 = sub nsw i32 %23, 1
  %25 = call noundef i64 @_Z13Fibonacci_Reci(i32 noundef %24)
  %26 = load i32, ptr %2, align 4, !tbaa !5
  %27 = sub nsw i32 %26, 2
  %28 = call noundef i64 @_Z13Fibonacci_Reci(i32 noundef %27)
  %29 = add nsw i64 %25, %28
  %30 = load i32, ptr %2, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [100 x i64], ptr @fib, i64 0, i64 %31
  store i64 %29, ptr %32, align 8, !tbaa !9
  br label %33

33:                                               ; preds = %22, %18
  br label %34

34:                                               ; preds = %33, %11
  br label %35

35:                                               ; preds = %34, %1
  %36 = load i32, ptr %2, align 4, !tbaa !5
  %37 = sext i32 %36 to i64
  %38 = getelementptr inbounds [100 x i64], ptr @fib, i64 0, i64 %37
  %39 = load i64, ptr %38, align 8, !tbaa !9
  ret i64 %39
}

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" }

!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 = !{!"long long", !7, i64 0}


; 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"

@fib = external dso_local local_unnamed_addr global [100 x i64], align 16

; Function Attrs: mustprogress nofree nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef i64 @_Z13Fibonacci_Reci(i32 noundef %0) local_unnamed_addr #0 {
  %2 = sext i32 %0 to i64
  %3 = getelementptr inbounds [100 x i64], ptr @fib, i64 0, i64 %2
  %4 = load i64, ptr %3, align 8, !tbaa !5
  %5 = icmp slt i64 %4, 0
  br i1 %5, label %6, label %14

6:                                                ; preds = %1
  switch i32 %0, label %8 [
    i32 0, label %.sink.split
    i32 1, label %7
  ]

7:                                                ; preds = %6
  br label %.sink.split

8:                                                ; preds = %6
  %9 = add nsw i32 %0, -1
  %10 = tail call noundef i64 @_Z13Fibonacci_Reci(i32 noundef %9)
  %11 = add nsw i32 %0, -2
  %12 = tail call noundef i64 @_Z13Fibonacci_Reci(i32 noundef %11)
  %13 = add nsw i64 %12, %10
  br label %.sink.split

.sink.split:                                      ; preds = %6, %7, %8
  %.sink = phi i64 [ %13, %8 ], [ 1, %7 ], [ 0, %6 ]
  store i64 %.sink, ptr %3, align 8, !tbaa !5
  br label %14

14:                                               ; preds = %.sink.split, %1
  %15 = phi i64 [ %4, %1 ], [ %.sink, %.sink.split ]
  ret i64 %15
}

attributes #0 = { mustprogress nofree nosync nounwind memory(readwrite, argmem: none, 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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,InstCombinePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass