; LLVM IR from bqi343/cp-notebook :: Contests/USACO Solutions/2008-09/lfence.ll (ZmiRKSt4pairIiiES2_)

; 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 @_ZmiRKSt4pairIiiES2_(ptr noundef nonnull align 4 dereferenceable(8) %0, ptr noundef nonnull align 4 dereferenceable(8) %1) #1 {
  %3 = alloca %"struct.std::pair", align 4
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  %9 = getelementptr inbounds %"struct.std::pair", ptr %8, i32 0, i32 0
  %10 = load i32, ptr %9, align 4, !tbaa !9
  %11 = load ptr, ptr %5, align 8, !tbaa !5
  %12 = getelementptr inbounds %"struct.std::pair", ptr %11, i32 0, i32 0
  %13 = load i32, ptr %12, align 4, !tbaa !9
  %14 = sub nsw i32 %10, %13
  store i32 %14, ptr %6, align 4, !tbaa !12
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds %"struct.std::pair", ptr %15, i32 0, i32 1
  %17 = load i32, ptr %16, align 4, !tbaa !13
  %18 = load ptr, ptr %5, align 8, !tbaa !5
  %19 = getelementptr inbounds %"struct.std::pair", ptr %18, i32 0, i32 1
  %20 = load i32, ptr %19, align 4, !tbaa !13
  %21 = sub nsw i32 %17, %20
  store i32 %21, ptr %7, align 4, !tbaa !12
  call void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXaaclsr5_PCCPE22_MoveConstructiblePairIT_T0_EEclsr5_PCCPE30_ImplicitlyMoveConvertiblePairIS3_S4_EEEbE4typeELb1EEEOS3_OS4_(ptr noundef nonnull align 4 dereferenceable(8) %3, ptr noundef nonnull align 4 dereferenceable(4) %6, ptr noundef nonnull align 4 dereferenceable(4) %7)
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  %22 = load i64, ptr %3, align 4
  ret i64 %22
}

; 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !11, i64 0}
!10 = !{!"_ZTSSt4pairIiiE", !11, i64 0, !11, i64 4}
!11 = !{!"int", !7, i64 0}
!12 = !{!11, !11, i64 0}
!13 = !{!10, !11, i64 4}


; 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 @_ZmiRKSt4pairIiiES2_(ptr nocapture noundef nonnull readonly align 4 dereferenceable(8) %0, ptr nocapture noundef nonnull readonly align 4 dereferenceable(8) %1) local_unnamed_addr #1 {
  %3 = alloca %"struct.std::pair", align 8
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %4) #2
  %6 = load i32, ptr %0, align 4, !tbaa !5
  %7 = load i32, ptr %1, align 4, !tbaa !5
  %8 = sub nsw i32 %6, %7
  store i32 %8, ptr %4, align 4, !tbaa !10
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %5) #2
  %9 = getelementptr inbounds i8, ptr %0, i64 4
  %10 = load i32, ptr %9, align 4, !tbaa !11
  %11 = getelementptr inbounds i8, ptr %1, i64 4
  %12 = load i32, ptr %11, align 4, !tbaa !11
  %13 = sub nsw i32 %10, %12
  store i32 %13, ptr %5, align 4, !tbaa !10
  call void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXaaclsr5_PCCPE22_MoveConstructiblePairIT_T0_EEclsr5_PCCPE30_ImplicitlyMoveConvertiblePairIS3_S4_EEEbE4typeELb1EEEOS3_OS4_(ptr noundef nonnull align 4 dereferenceable(8) %3, 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 nonnull %5) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %4) #2
  %14 = load i64, ptr %3, align 8
  ret i64 %14
}

; 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, !7, i64 0}
!6 = !{!"_ZTSSt4pairIiiE", !7, i64 0, !7, i64 4}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!7, !7, i64 0}
!11 = !{!6, !7, i64 4}


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