; LLVM IR from upupming/algorithm :: acwing/算法竞赛进阶指南/0x41-并查集/237. 程序自动分析.ll (Z5mergeii)

; 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"

@fa = external dso_local global [1000010 x i32], align 16
@sz = external dso_local global [1000010 x i32], align 16

; 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
declare dso_local noundef i32 @_Z3geti(i32 noundef) #1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z5mergeii(i32 noundef %0, i32 noundef %1) #1 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  %8 = load i32, ptr %3, align 4, !tbaa !5
  %9 = call noundef i32 @_Z3geti(i32 noundef %8)
  store i32 %9, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %10 = load i32, ptr %4, align 4, !tbaa !5
  %11 = call noundef i32 @_Z3geti(i32 noundef %10)
  store i32 %11, ptr %6, align 4, !tbaa !5
  %12 = load i32, ptr %5, align 4, !tbaa !5
  %13 = load i32, ptr %6, align 4, !tbaa !5
  %14 = icmp eq i32 %12, %13
  br i1 %14, label %15, label %16

15:                                               ; preds = %2
  store i32 1, ptr %7, align 4
  br label %55

16:                                               ; preds = %2
  %17 = load i32, ptr %5, align 4, !tbaa !5
  %18 = sext i32 %17 to i64
  %19 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %18
  %20 = load i32, ptr %19, align 4, !tbaa !5
  %21 = load i32, ptr %6, align 4, !tbaa !5
  %22 = sext i32 %21 to i64
  %23 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %22
  %24 = load i32, ptr %23, align 4, !tbaa !5
  %25 = icmp slt i32 %20, %24
  br i1 %25, label %26, label %40

26:                                               ; preds = %16
  %27 = load i32, ptr %6, align 4, !tbaa !5
  %28 = load i32, ptr %5, align 4, !tbaa !5
  %29 = sext i32 %28 to i64
  %30 = getelementptr inbounds [1000010 x i32], ptr @fa, i64 0, i64 %29
  store i32 %27, ptr %30, align 4, !tbaa !5
  %31 = load i32, ptr %5, align 4, !tbaa !5
  %32 = sext i32 %31 to i64
  %33 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %32
  %34 = load i32, ptr %33, align 4, !tbaa !5
  %35 = load i32, ptr %6, align 4, !tbaa !5
  %36 = sext i32 %35 to i64
  %37 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %36
  %38 = load i32, ptr %37, align 4, !tbaa !5
  %39 = add nsw i32 %38, %34
  store i32 %39, ptr %37, align 4, !tbaa !5
  br label %54

40:                                               ; preds = %16
  %41 = load i32, ptr %5, align 4, !tbaa !5
  %42 = load i32, ptr %6, align 4, !tbaa !5
  %43 = sext i32 %42 to i64
  %44 = getelementptr inbounds [1000010 x i32], ptr @fa, i64 0, i64 %43
  store i32 %41, ptr %44, align 4, !tbaa !5
  %45 = load i32, ptr %6, align 4, !tbaa !5
  %46 = sext i32 %45 to i64
  %47 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %46
  %48 = load i32, ptr %47, align 4, !tbaa !5
  %49 = load i32, ptr %5, align 4, !tbaa !5
  %50 = sext i32 %49 to i64
  %51 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %50
  %52 = load i32, ptr %51, align 4, !tbaa !5
  %53 = add nsw i32 %52, %48
  store i32 %53, ptr %51, align 4, !tbaa !5
  br label %54

54:                                               ; preds = %40, %26
  store i32 0, ptr %7, align 4
  br label %55

55:                                               ; preds = %54, %15
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  %56 = load i32, ptr %7, align 4
  switch i32 %56, label %58 [
    i32 0, label %57
    i32 1, label %57
  ]

57:                                               ; preds = %55, %55
  ret void

58:                                               ; preds = %55
  unreachable
}

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 = { 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"

@fa = external dso_local local_unnamed_addr global [1000010 x i32], align 16
@sz = external dso_local local_unnamed_addr global [1000010 x i32], align 16

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3geti(i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
define dso_local void @_Z5mergeii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = tail call noundef i32 @_Z3geti(i32 noundef %0)
  %4 = tail call noundef i32 @_Z3geti(i32 noundef %1)
  %5 = icmp eq i32 %3, %4
  br i1 %5, label %15, label %.sink.split

.sink.split:                                      ; preds = %2
  %6 = sext i32 %3 to i64
  %7 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %6
  %8 = load i32, ptr %7, align 4, !tbaa !5
  %9 = sext i32 %4 to i64
  %10 = getelementptr inbounds [1000010 x i32], ptr @sz, i64 0, i64 %9
  %11 = load i32, ptr %10, align 4, !tbaa !5
  %12 = icmp slt i32 %8, %11
  %13 = add nsw i32 %11, %8
  %. = select i1 %12, i64 %6, i64 %9
  %.18 = select i1 %12, i32 %4, i32 %3
  %.19 = select i1 %12, ptr %10, ptr %7
  %14 = getelementptr inbounds [1000010 x i32], ptr @fa, i64 0, i64 %.
  store i32 %.18, ptr %14, align 4, !tbaa !5
  store i32 %13, ptr %.19, align 4, !tbaa !5
  br label %15

15:                                               ; preds = %.sink.split, %2
  ret void
}

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" }

!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: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass