; LLVM IR from Lodour/ACM-CheatSheet :: src/2_数学/1_素数/1_埃氏筛.ll (Z8GetPrimev)

; 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"

@notprime = external dso_local global <{ i8, i8, [1000098 x i8] }>, align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z8GetPrimev() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %1) #2
  store i32 2, ptr %1, align 4, !tbaa !5
  br label %4

4:                                                ; preds = %37, %0
  %5 = load i32, ptr %1, align 4, !tbaa !5
  %6 = icmp slt i32 %5, 1000100
  br i1 %6, label %8, label %7

7:                                                ; preds = %4
  store i32 2, ptr %2, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %1) #2
  br label %40

8:                                                ; preds = %4
  %9 = load i32, ptr %1, align 4, !tbaa !5
  %10 = sext i32 %9 to i64
  %11 = getelementptr inbounds [1000100 x i8], ptr @notprime, i64 0, i64 %10
  %12 = load i8, ptr %11, align 1, !tbaa !9, !range !11, !noundef !12
  %13 = trunc i8 %12 to i1
  br i1 %13, label %36, label %14

14:                                               ; preds = %8
  %15 = load i32, ptr %1, align 4, !tbaa !5
  %16 = load i32, ptr %1, align 4, !tbaa !5
  %17 = sdiv i32 1000100, %16
  %18 = icmp sle i32 %15, %17
  br i1 %18, label %19, label %36

19:                                               ; preds = %14
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  %20 = load i32, ptr %1, align 4, !tbaa !5
  %21 = load i32, ptr %1, align 4, !tbaa !5
  %22 = mul nsw i32 %20, %21
  store i32 %22, ptr %3, align 4, !tbaa !5
  br label %23

23:                                               ; preds = %31, %19
  %24 = load i32, ptr %3, align 4, !tbaa !5
  %25 = icmp slt i32 %24, 1000100
  br i1 %25, label %27, label %26

26:                                               ; preds = %23
  store i32 5, ptr %2, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  br label %35

27:                                               ; preds = %23
  %28 = load i32, ptr %3, align 4, !tbaa !5
  %29 = sext i32 %28 to i64
  %30 = getelementptr inbounds [1000100 x i8], ptr @notprime, i64 0, i64 %29
  store i8 1, ptr %30, align 1, !tbaa !9
  br label %31

31:                                               ; preds = %27
  %32 = load i32, ptr %1, align 4, !tbaa !5
  %33 = load i32, ptr %3, align 4, !tbaa !5
  %34 = add nsw i32 %33, %32
  store i32 %34, ptr %3, align 4, !tbaa !5
  br label %23, !llvm.loop !13

35:                                               ; preds = %26
  br label %36

36:                                               ; preds = %35, %14, %8
  br label %37

37:                                               ; preds = %36
  %38 = load i32, ptr %1, align 4, !tbaa !5
  %39 = add nsw i32 %38, 1
  store i32 %39, ptr %1, align 4, !tbaa !5
  br label %4, !llvm.loop !15

40:                                               ; preds = %7
  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: 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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"}
!9 = !{!10, !10, i64 0}
!10 = !{!"bool", !7, i64 0}
!11 = !{i8 0, i8 2}
!12 = !{}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = distinct !{!15, !14}


; 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"

@notprime = external dso_local local_unnamed_addr global <{ i8, i8, [1000098 x i8] }>, align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
define dso_local void @_Z8GetPrimev() local_unnamed_addr #0 {
  br label %2

1:                                                ; preds = %.loopexit
  ret void

2:                                                ; preds = %0, %.loopexit
  %indvars.iv23 = phi i64 [ 5, %0 ], [ %indvars.iv.next24, %.loopexit ]
  %indvars.iv18 = phi i64 [ 2, %0 ], [ %indvars.iv.next19, %.loopexit ]
  %indvars.iv16 = phi i32 [ 4, %0 ], [ %indvars.iv.next17, %.loopexit ]
  %3 = getelementptr inbounds [1000100 x i8], ptr @notprime, i64 0, i64 %indvars.iv18
  %4 = load i8, ptr %3, align 1, !tbaa !5, !range !9, !noundef !10
  %5 = trunc nuw i8 %4 to i1
  br i1 %5, label %.loopexit, label %6

6:                                                ; preds = %2
  %7 = trunc nuw nsw i64 %indvars.iv18 to i32
  %8 = udiv i32 1000100, %7
  %9 = zext nneg i32 %8 to i64
  %.not = icmp ule i64 %indvars.iv18, %9
  %10 = mul nuw nsw i64 %indvars.iv18, %indvars.iv18
  %11 = icmp ult i64 %10, 1000100
  %or.cond = select i1 %.not, i1 %11, i1 false
  br i1 %or.cond, label %.lr.ph.preheader, label %.loopexit

.lr.ph.preheader:                                 ; preds = %6
  %12 = zext i32 %indvars.iv16 to i64
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %indvars.iv20 = phi i64 [ %indvars.iv.next21, %.lr.ph ], [ %12, %.lr.ph.preheader ]
  %13 = getelementptr inbounds [1000100 x i8], ptr @notprime, i64 0, i64 %indvars.iv20
  store i8 1, ptr %13, align 1, !tbaa !5
  %indvars.iv.next21 = add nuw nsw i64 %indvars.iv20, %indvars.iv18
  %14 = icmp ult i64 %indvars.iv.next21, 1000100
  br i1 %14, label %.lr.ph, label %.loopexit, !llvm.loop !11

.loopexit:                                        ; preds = %.lr.ph, %2, %6
  %indvars.iv.next19 = add nuw nsw i64 %indvars.iv18, 1
  %indvars.iv.next24 = add nuw nsw i64 %indvars.iv23, 2
  %15 = trunc nuw nsw i64 %indvars.iv23 to i32
  %indvars.iv.next17 = add i32 %indvars.iv16, %15
  %exitcond.not = icmp eq i64 %indvars.iv.next19, 1000100
  br i1 %exitcond.not, label %1, label %2, !llvm.loop !13
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: 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 = !{!6, !6, i64 0}
!6 = !{!"bool", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{i8 0, i8 2}
!10 = !{}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !12}


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