; LLVM IR from tangjz/acm-icpc :: lydsy/1543.ll (Z8dsu_findi)

; 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"

@dsu = external dso_local global [50001 x i32], align 16

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z8dsu_findi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  %3 = load i32, ptr %2, align 4, !tbaa !5
  %4 = sext i32 %3 to i64
  %5 = getelementptr inbounds [50001 x i32], ptr @dsu, i64 0, i64 %4
  %6 = load i32, ptr %5, align 4, !tbaa !5
  %7 = icmp slt i32 %6, 0
  br i1 %7, label %8, label %10

8:                                                ; preds = %1
  %9 = load i32, ptr %2, align 4, !tbaa !5
  br label %16

10:                                               ; preds = %1
  %11 = load i32, ptr %2, align 4, !tbaa !5
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds [50001 x i32], ptr @dsu, i64 0, i64 %12
  %14 = load i32, ptr %13, align 4, !tbaa !5
  %15 = call noundef i32 @_Z8dsu_findi(i32 noundef %14)
  br label %16

16:                                               ; preds = %10, %8
  %17 = phi i32 [ %9, %8 ], [ %15, %10 ]
  ret i32 %17
}

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"}


; 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"

@dsu = external dso_local local_unnamed_addr global [50001 x i32], align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef i32 @_Z8dsu_findi(i32 noundef %0) local_unnamed_addr #0 {
  br label %tailrecurse

tailrecurse:                                      ; preds = %tailrecurse, %1
  %.tr = phi i32 [ %0, %1 ], [ %4, %tailrecurse ]
  %2 = sext i32 %.tr to i64
  %3 = getelementptr inbounds [50001 x i32], ptr @dsu, i64 0, i64 %2
  %4 = load i32, ptr %3, align 4, !tbaa !5
  %5 = icmp slt i32 %4, 0
  br i1 %5, label %6, label %tailrecurse

6:                                                ; preds = %tailrecurse
  ret i32 %.tr
}

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"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass