; LLVM IR from upupming/algorithm :: acwing/算法竞赛进阶指南/0x29-总结与练习/186. 巴士.ll (Z5checkii)

; 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"

@bus = external dso_local global [60 x i32], align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef zeroext i1 @_Z5checkii(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i1, align 1
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %8 = load i32, ptr %4, align 4, !tbaa !5
  store i32 %8, ptr %6, align 4, !tbaa !5
  br label %9

9:                                                ; preds = %21, %2
  %10 = load i32, ptr %6, align 4, !tbaa !5
  %11 = icmp slt i32 %10, 60
  br i1 %11, label %13, label %12

12:                                               ; preds = %9
  store i32 2, ptr %7, align 4
  br label %25

13:                                               ; preds = %9
  %14 = load i32, ptr %6, align 4, !tbaa !5
  %15 = sext i32 %14 to i64
  %16 = getelementptr inbounds [60 x i32], ptr @bus, i64 0, i64 %15
  %17 = load i32, ptr %16, align 4, !tbaa !5
  %18 = icmp ne i32 %17, 0
  br i1 %18, label %20, label %19

19:                                               ; preds = %13
  store i1 false, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %25

20:                                               ; preds = %13
  br label %21

21:                                               ; preds = %20
  %22 = load i32, ptr %5, align 4, !tbaa !5
  %23 = load i32, ptr %6, align 4, !tbaa !5
  %24 = add nsw i32 %23, %22
  store i32 %24, ptr %6, align 4, !tbaa !5
  br label %9, !llvm.loop !9

25:                                               ; preds = %19, %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %26 = load i32, ptr %7, align 4
  switch i32 %26, label %30 [
    i32 2, label %27
    i32 1, label %28
  ]

27:                                               ; preds = %25
  store i1 true, ptr %3, align 1
  br label %28

28:                                               ; preds = %27, %25
  %29 = load i1, ptr %3, align 1
  ret i1 %29

30:                                               ; preds = %25
  unreachable
}

; 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 = 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"

@bus = external dso_local local_unnamed_addr global [60 x i32], align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef zeroext i1 @_Z5checkii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i32 %0, 59
  br i1 %3, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %2
  %4 = sext i32 %0 to i64
  %5 = sext i32 %1 to i64
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader
  %indvars.iv = phi i64 [ %4, %.lr.ph.preheader ], [ %indvars.iv.next, %.lr.ph ]
  %6 = getelementptr inbounds [60 x i32], ptr @bus, i64 0, i64 %indvars.iv
  %7 = load i32, ptr %6, align 4, !tbaa !5
  %.not.not = icmp ne i32 %7, 0
  %indvars.iv.next = add nsw i64 %indvars.iv, %5
  %8 = icmp slt i64 %indvars.iv.next, 60
  %or.cond.not = select i1 %.not.not, i1 %8, i1 false
  br i1 %or.cond.not, label %.lr.ph, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.lcssa = phi i1 [ true, %2 ], [ %.not.not, %.lr.ph ]
  ret i1 %.lcssa
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(read, 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 = !{!"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: CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass