; LLVM IR from bqi343/cp-notebook :: Contests/USACO Solutions/2018-19/Open 2019/Gold/walk (13:15).ll (Z4rhshi)

; 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"

%"struct.std::pair" = type { i32, i32 }

; 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 uwtable
define dso_local i64 @_Z4rhshi(i32 noundef %0) #1 {
  %2 = alloca %"struct.std::pair", align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  %6 = load i32, ptr %3, align 4, !tbaa !5
  %7 = ashr i32 %6, 16
  store i32 %7, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  %8 = load i32, ptr %3, align 4, !tbaa !5
  %9 = and i32 %8, 65535
  store i32 %9, ptr %5, align 4, !tbaa !5
  call void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXaaclsr5_PCCPE22_MoveConstructiblePairIT_T0_EEclsr5_PCCPE30_ImplicitlyMoveConvertiblePairIS3_S4_EEEbE4typeELb1EEEOS3_OS4_(ptr noundef nonnull align 4 dereferenceable(8) %2, ptr noundef nonnull align 4 dereferenceable(4) %4, ptr noundef nonnull align 4 dereferenceable(4) %5)
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  %10 = load i64, ptr %2, align 4
  ret i64 %10
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXaaclsr5_PCCPE22_MoveConstructiblePairIT_T0_EEclsr5_PCCPE30_ImplicitlyMoveConvertiblePairIS3_S4_EEEbE4typeELb1EEEOS3_OS4_(ptr noundef nonnull align 4 dereferenceable(8), ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) unnamed_addr #2 align 2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #2 = { 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 #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++ 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"

%"struct.std::pair" = type { i32, i32 }

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

; Function Attrs: mustprogress 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 i64 @_Z4rhshi(i32 noundef %0) local_unnamed_addr #1 {
  %2 = alloca %"struct.std::pair", align 8
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #2
  %5 = ashr i32 %0, 16
  store i32 %5, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %4) #2
  %6 = and i32 %0, 65535
  store i32 %6, ptr %4, align 4, !tbaa !5
  call void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXaaclsr5_PCCPE22_MoveConstructiblePairIT_T0_EEclsr5_PCCPE30_ImplicitlyMoveConvertiblePairIS3_S4_EEEbE4typeELb1EEEOS3_OS4_(ptr noundef nonnull align 4 dereferenceable(8) %2, ptr noundef nonnull align 4 dereferenceable(4) %3, ptr noundef nonnull align 4 dereferenceable(4) %4)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %4) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #2
  %7 = load i64, ptr %2, align 8
  ret i64 %7
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXaaclsr5_PCCPE22_MoveConstructiblePairIT_T0_EEclsr5_PCCPE30_ImplicitlyMoveConvertiblePairIS3_S4_EEEbE4typeELb1EEEOS3_OS4_(ptr noundef nonnull align 4 dereferenceable(8), ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) unnamed_addr #1 align 2

attributes #0 = { mustprogress 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}


; Effective O3 passes: GlobalOptPass,InferAlignmentPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass