; LLVM IR from Chasmiccoder/Algos-for-Amigos :: Mathematics/Series (p01_fibonacci_series)

; 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: 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 @_Z61naive_approach_last_digit_of_sum_of_first_n_fibonacci_numbersx(i64 noundef %0) #1 {
  %2 = alloca i64, align 8
  %3 = alloca i64, align 8
  %4 = alloca i64, align 8
  %5 = alloca i64, align 8
  %6 = alloca i64, align 8
  %7 = alloca i64, align 8
  store i64 %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #2
  store i64 1, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  store i64 1, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  store i64 0, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  store i64 2, ptr %6, align 8, !tbaa !5
  br label %8

8:                                                ; preds = %23, %1
  %9 = load i64, ptr %6, align 8, !tbaa !5
  %10 = load i64, ptr %2, align 8, !tbaa !5
  %11 = icmp sle i64 %9, %10
  br i1 %11, label %13, label %12

12:                                               ; preds = %8
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  br label %26

13:                                               ; preds = %8
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #2
  %14 = load i64, ptr %5, align 8, !tbaa !5
  store i64 %14, ptr %7, align 8, !tbaa !5
  %15 = load i64, ptr %4, align 8, !tbaa !5
  store i64 %15, ptr %5, align 8, !tbaa !5
  %16 = load i64, ptr %4, align 8, !tbaa !5
  %17 = load i64, ptr %7, align 8, !tbaa !5
  %18 = add nsw i64 %16, %17
  store i64 %18, ptr %4, align 8, !tbaa !5
  %19 = load i64, ptr %4, align 8, !tbaa !5
  %20 = srem i64 %19, 10
  %21 = load i64, ptr %3, align 8, !tbaa !5
  %22 = add nsw i64 %21, %20
  store i64 %22, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #2
  br label %23

23:                                               ; preds = %13
  %24 = load i64, ptr %6, align 8, !tbaa !5
  %25 = add nsw i64 %24, 1
  store i64 %25, ptr %6, align 8, !tbaa !5
  br label %8, !llvm.loop !9

26:                                               ; preds = %12
  %27 = load i64, ptr %3, align 8, !tbaa !5
  %28 = srem i64 %27, 10
  %29 = trunc i64 %28 to i32
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #2
  ret i32 %29
}

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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"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"

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) uwtable
define dso_local noundef range(i32 -9, 10) i32 @_Z61naive_approach_last_digit_of_sum_of_first_n_fibonacci_numbersx(i64 noundef %0) local_unnamed_addr #0 {
  %.not13 = icmp slt i64 %0, 2
  br i1 %.not13, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %1
  %2 = add nsw i64 %0, -1
  %xtraiter = and i64 %2, 1
  %3 = icmp eq i64 %0, 2
  br i1 %3, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i64 %2, -2
  br label %.lr.ph

._crit_edge.loopexit.unr-lcssa:                   ; preds = %.lr.ph, %.lr.ph.preheader
  %.lcssa.ph = phi i64 [ poison, %.lr.ph.preheader ], [ %14, %.lr.ph ]
  %.017.unr = phi i64 [ 1, %.lr.ph.preheader ], [ %14, %.lr.ph ]
  %.01115.unr = phi i64 [ 0, %.lr.ph.preheader ], [ %9, %.lr.ph ]
  %.01214.unr = phi i64 [ 1, %.lr.ph.preheader ], [ %12, %.lr.ph ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge.loopexit, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa
  %4 = add nsw i64 %.01115.unr, %.01214.unr
  %5 = srem i64 %4, 10
  %6 = add nsw i64 %.017.unr, %5
  br label %._crit_edge.loopexit

._crit_edge.loopexit:                             ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil
  %.lcssa = phi i64 [ %.lcssa.ph, %._crit_edge.loopexit.unr-lcssa ], [ %6, %.lr.ph.epil ]
  %7 = srem i64 %.lcssa, 10
  %8 = trunc nsw i64 %7 to i32
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %1
  %.0.lcssa = phi i32 [ 1, %1 ], [ %8, %._crit_edge.loopexit ]
  ret i32 %.0.lcssa

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader.new
  %.017 = phi i64 [ 1, %.lr.ph.preheader.new ], [ %14, %.lr.ph ]
  %.01115 = phi i64 [ 0, %.lr.ph.preheader.new ], [ %9, %.lr.ph ]
  %.01214 = phi i64 [ 1, %.lr.ph.preheader.new ], [ %12, %.lr.ph ]
  %niter = phi i64 [ 0, %.lr.ph.preheader.new ], [ %niter.next.1, %.lr.ph ]
  %9 = add nsw i64 %.01115, %.01214
  %10 = srem i64 %9, 10
  %11 = add nsw i64 %.017, %10
  %12 = add nsw i64 %.01214, %9
  %13 = srem i64 %12, 10
  %14 = add nsw i64 %11, %13
  %niter.next.1 = add i64 %niter, 2
  %niter.ncmp.1 = icmp eq i64 %niter.next.1, %unroll_iter
  br i1 %niter.ncmp.1, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !5
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass