; LLVM IR from lzyrapx/Competitive-Programming :: 百度之星/2019/1002.ll (Z6updatei)

; 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"

@a = external dso_local global [1000123 x i32], align 16
@pos = external dso_local global [1000123 x i32], align 16
@num = external dso_local global i32, align 4

; Function Attrs: mustprogress uwtable
define dso_local void @_Z6updatei(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  store i32 1, ptr %3, align 4, !tbaa !5
  br label %5

5:                                                ; preds = %36, %1
  %6 = load i32, ptr %3, align 4, !tbaa !5
  %7 = load i32, ptr @num, align 4, !tbaa !5
  %8 = icmp sle i32 %6, %7
  br i1 %8, label %10, label %9

9:                                                ; preds = %5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  br label %39

10:                                               ; preds = %5
  %11 = load i32, ptr %2, align 4, !tbaa !5
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds [1000123 x i32], ptr @a, i64 0, i64 %12
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #4
  %14 = load i32, ptr %3, align 4, !tbaa !5
  %15 = sext i32 %14 to i64
  %16 = getelementptr inbounds [1000123 x i32], ptr @a, i64 0, i64 %15
  %17 = load i32, ptr %16, align 4, !tbaa !5
  %18 = load i32, ptr %3, align 4, !tbaa !5
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds [1000123 x i32], ptr @pos, i64 0, i64 %19
  %21 = load i32, ptr %20, align 4, !tbaa !5
  %22 = load i32, ptr %2, align 4, !tbaa !5
  %23 = sext i32 %22 to i64
  %24 = getelementptr inbounds [1000123 x i32], ptr @pos, i64 0, i64 %23
  %25 = load i32, ptr %24, align 4, !tbaa !5
  %26 = sub nsw i32 %21, %25
  %27 = call i32 @llvm.abs.i32(i32 %26, i1 true)
  %28 = add nsw i32 %27, 1
  %29 = sdiv i32 %28, 2
  %30 = add nsw i32 %17, %29
  store i32 %30, ptr %4, align 4, !tbaa !5
  %31 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3minIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) %13, ptr noundef nonnull align 4 dereferenceable(4) %4)
  %32 = load i32, ptr %31, align 4, !tbaa !5
  %33 = load i32, ptr %2, align 4, !tbaa !5
  %34 = sext i32 %33 to i64
  %35 = getelementptr inbounds [1000123 x i32], ptr @a, i64 0, i64 %34
  store i32 %32, ptr %35, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #4
  br label %36

36:                                               ; preds = %10
  %37 = load i32, ptr %3, align 4, !tbaa !5
  %38 = add nsw i32 %37, 1
  store i32 %38, ptr %3, align 4, !tbaa !5
  br label %5, !llvm.loop !9

39:                                               ; preds = %9
  ret void
}

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

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3minIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) #2

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.abs.i32(i32, i1 immarg) #3

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

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 = { inlinehint 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 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
attributes #4 = { 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"}
!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"

@a = external dso_local global [1000123 x i32], align 16
@pos = external dso_local local_unnamed_addr global [1000123 x i32], align 16
@num = external dso_local local_unnamed_addr global i32, align 4

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z6updatei(i32 noundef %0) local_unnamed_addr #0 {
  %2 = alloca i32, align 4
  %3 = load i32, ptr @num, align 4, !tbaa !5
  %.not7 = icmp slt i32 %3, 1
  br i1 %.not7, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1
  %4 = sext i32 %0 to i64
  %5 = getelementptr inbounds [1000123 x i32], ptr @a, i64 0, i64 %4
  %6 = getelementptr inbounds [1000123 x i32], ptr @pos, i64 0, i64 %4
  br label %7

._crit_edge:                                      ; preds = %7, %1
  ret void

7:                                                ; preds = %.lr.ph, %7
  %indvars.iv = phi i64 [ 1, %.lr.ph ], [ %indvars.iv.next, %7 ]
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #4
  %8 = getelementptr inbounds [1000123 x i32], ptr @a, i64 0, i64 %indvars.iv
  %9 = load i32, ptr %8, align 4, !tbaa !5
  %10 = getelementptr inbounds [1000123 x i32], ptr @pos, i64 0, i64 %indvars.iv
  %11 = load i32, ptr %10, align 4, !tbaa !5
  %12 = load i32, ptr %6, align 4, !tbaa !5
  %13 = sub nsw i32 %11, %12
  %14 = call i32 @llvm.abs.i32(i32 %13, i1 true)
  %15 = add nuw nsw i32 %14, 1
  %16 = lshr i32 %15, 1
  %17 = add nsw i32 %16, %9
  store i32 %17, ptr %2, align 4, !tbaa !5
  %18 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3minIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) %5, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %19 = load i32, ptr %18, align 4, !tbaa !5
  store i32 %19, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #4
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %20 = load i32, ptr @num, align 4, !tbaa !5
  %21 = sext i32 %20 to i64
  %.not.not = icmp slt i64 %indvars.iv, %21
  br i1 %.not.not, label %7, label %._crit_edge, !llvm.loop !9
}

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

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3minIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

; Function Attrs: mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.abs.i32(i32, i1 immarg) #3

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

attributes #0 = { 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { inlinehint 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 = { mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none) }
attributes #4 = { 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"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass