; LLVM IR from Izaron/ACM-ICPC :: Russian Council of School Olympiads (R.S.O.Sh.)/IOIP/IOIP 2013/hat.ll (Z4gettxx)

; 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
define dso_local noundef i32 @_Z4gettxx(i64 noundef %0, i64 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i64, align 8
  %5 = alloca i64, align 8
  store i64 %0, ptr %4, align 8, !tbaa !5
  store i64 %1, ptr %5, align 8, !tbaa !5
  %6 = load i64, ptr %4, align 8, !tbaa !5
  %7 = icmp eq i64 %6, 1
  br i1 %7, label %8, label %9

8:                                                ; preds = %2
  store i32 0, ptr %3, align 4
  br label %28

9:                                                ; preds = %2
  %10 = load i64, ptr %4, align 8, !tbaa !5
  %11 = load i64, ptr %5, align 8, !tbaa !5
  %12 = sdiv i64 %11, 2
  %13 = icmp sle i64 %10, %12
  br i1 %13, label %14, label %19

14:                                               ; preds = %9
  %15 = load i64, ptr %4, align 8, !tbaa !5
  %16 = load i64, ptr %5, align 8, !tbaa !5
  %17 = sdiv i64 %16, 2
  %18 = call noundef i32 @_Z4gettxx(i64 noundef %15, i64 noundef %17)
  store i32 %18, ptr %3, align 4
  br label %28

19:                                               ; preds = %9
  %20 = load i64, ptr %4, align 8, !tbaa !5
  %21 = load i64, ptr %5, align 8, !tbaa !5
  %22 = sdiv i64 %21, 2
  %23 = sub nsw i64 %20, %22
  %24 = load i64, ptr %5, align 8, !tbaa !5
  %25 = sdiv i64 %24, 2
  %26 = call noundef i32 @_Z4gettxx(i64 noundef %23, i64 noundef %25)
  %27 = add nsw i32 %26, 1
  store i32 %27, ptr %3, align 4
  br label %28

28:                                               ; preds = %19, %14, %8
  %29 = load i32, ptr %3, align 4
  ret i32 %29
}

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


; 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 i32 @_Z4gettxx(i64 noundef %0, i64 noundef %1) local_unnamed_addr #0 {
  %3 = icmp eq i64 %0, 1
  br i1 %3, label %tailrecurse.outer._crit_edge, label %tailrecurse.outer.split

tailrecurse.outer.split:                          ; preds = %2, %tailrecurse.outer
  %.tr11.ph14 = phi i64 [ %4, %tailrecurse.outer ], [ %1, %2 ]
  %.tr.ph13 = phi i64 [ %5, %tailrecurse.outer ], [ %0, %2 ]
  %accumulator.tr.ph12 = phi i32 [ %6, %tailrecurse.outer ], [ 0, %2 ]
  br label %tailrecurse

tailrecurse:                                      ; preds = %tailrecurse.outer.split, %tailrecurse
  %.tr11 = phi i64 [ %4, %tailrecurse ], [ %.tr11.ph14, %tailrecurse.outer.split ]
  %4 = sdiv i64 %.tr11, 2
  %.not = icmp slt i64 %4, %.tr.ph13
  br i1 %.not, label %tailrecurse.outer, label %tailrecurse

tailrecurse.outer:                                ; preds = %tailrecurse
  %5 = sub nsw i64 %.tr.ph13, %4
  %6 = add nuw nsw i32 %accumulator.tr.ph12, 1
  %7 = icmp eq i64 %5, 1
  br i1 %7, label %tailrecurse.outer._crit_edge, label %tailrecurse.outer.split

tailrecurse.outer._crit_edge:                     ; preds = %tailrecurse.outer, %2
  %accumulator.tr.ph.lcssa = phi i32 [ 0, %2 ], [ %6, %tailrecurse.outer ]
  ret i32 %accumulator.tr.ph.lcssa
}

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)"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyCFGPass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass