; LLVM IR from tangjz/acm-icpc :: 51nod/1399.ll (Z7sum_fibx)

; 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"

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3fibx(i64 noundef) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z7sum_fibx(i64 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i64, align 8
  %4 = alloca i32, align 4
  store i64 %0, ptr %3, align 8, !tbaa !5
  %5 = load i64, ptr %3, align 8, !tbaa !5
  %6 = icmp sle i64 %5, 0
  br i1 %6, label %7, label %8

7:                                                ; preds = %1
  store i32 0, ptr %2, align 4
  br label %22

8:                                                ; preds = %1
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  %9 = load i64, ptr %3, align 8, !tbaa !5
  %10 = add nsw i64 %9, 2
  %11 = call noundef i32 @_Z3fibx(i64 noundef %10)
  %12 = sub nsw i32 %11, 1
  store i32 %12, ptr %4, align 4, !tbaa !9
  %13 = load i32, ptr %4, align 4, !tbaa !9
  %14 = icmp slt i32 %13, 0
  br i1 %14, label %15, label %18

15:                                               ; preds = %8
  %16 = load i32, ptr %4, align 4, !tbaa !9
  %17 = add nsw i32 %16, 1000000007
  br label %20

18:                                               ; preds = %8
  %19 = load i32, ptr %4, align 4, !tbaa !9
  br label %20

20:                                               ; preds = %18, %15
  %21 = phi i32 [ %17, %15 ], [ %19, %18 ]
  store i32 %21, ptr %2, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %22

22:                                               ; preds = %20, %7
  %23 = load i32, ptr %2, align 4
  ret i32 %23
}

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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !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"

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3fibx(i64 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z7sum_fibx(i64 noundef %0) local_unnamed_addr #0 {
  %2 = icmp slt i64 %0, 1
  br i1 %2, label %8, label %3

3:                                                ; preds = %1
  %4 = add nuw nsw i64 %0, 2
  %5 = tail call noundef i32 @_Z3fibx(i64 noundef %4)
  %6 = icmp slt i32 %5, 1
  %.v = select i1 %6, i32 1000000006, i32 -1
  %7 = add nsw i32 %.v, %5
  br label %8

8:                                                ; preds = %1, %3
  %.0 = phi i32 [ %7, %3 ], [ 0, %1 ]
  ret i32 %.0
}

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)"}


; Effective O3 passes: GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass