; LLVM IR from HarshCasper/NeoAlgo :: C-Plus-Plus/ds (Find_first_and_last_positions_of_an_element_in_a_sorted_array)

; 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"

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z15First_positionsPiii(ptr noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  store i32 %2, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  store i32 -1, ptr %8, align 4, !tbaa !9
  store i32 0, ptr %7, align 4, !tbaa !9
  br label %9

9:                                                ; preds = %24, %3
  %10 = load i32, ptr %7, align 4, !tbaa !9
  %11 = load i32, ptr %5, align 4, !tbaa !9
  %12 = icmp slt i32 %10, %11
  br i1 %12, label %13, label %27

13:                                               ; preds = %9
  %14 = load ptr, ptr %4, align 8, !tbaa !5
  %15 = load i32, ptr %7, align 4, !tbaa !9
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds i32, ptr %14, i64 %16
  %18 = load i32, ptr %17, align 4, !tbaa !9
  %19 = load i32, ptr %6, align 4, !tbaa !9
  %20 = icmp eq i32 %18, %19
  br i1 %20, label %21, label %23

21:                                               ; preds = %13
  %22 = load i32, ptr %7, align 4, !tbaa !9
  store i32 %22, ptr %8, align 4, !tbaa !9
  br label %27

23:                                               ; preds = %13
  br label %24

24:                                               ; preds = %23
  %25 = load i32, ptr %7, align 4, !tbaa !9
  %26 = add nsw i32 %25, 1
  store i32 %26, ptr %7, align 4, !tbaa !9
  br label %9, !llvm.loop !11

27:                                               ; preds = %21, %9
  %28 = load i32, ptr %8, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  ret i32 %28
}

; 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"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"

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read) uwtable
define dso_local noundef i32 @_Z15First_positionsPiii(ptr nocapture noundef readonly %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = icmp sgt i32 %1, 0
  br i1 %4, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %3
  %wide.trip.count = zext nneg i32 %1 to i64
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %8
  %indvars.iv = phi i64 [ 0, %.lr.ph.preheader ], [ %indvars.iv.next, %8 ]
  %5 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %6 = load i32, ptr %5, align 4, !tbaa !5
  %7 = icmp eq i32 %6, %2
  br i1 %7, label %._crit_edge.loopexit.split.loop.exit, label %8

8:                                                ; preds = %.lr.ph
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

._crit_edge.loopexit.split.loop.exit:             ; preds = %.lr.ph
  %9 = trunc nuw nsw i64 %indvars.iv to i32
  br label %._crit_edge

._crit_edge:                                      ; preds = %8, %._crit_edge.loopexit.split.loop.exit, %3
  %.0 = phi i32 [ -1, %3 ], [ %9, %._crit_edge.loopexit.split.loop.exit ], [ -1, %8 ]
  ret i32 %.0
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read) 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: GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass