; LLVM IR from sachuverma/DataStructures-Algorithms :: DSA Crack Sheet/solutions/Majority Element.ll (Z15majorityElementPii)

; 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
declare dso_local noundef i32 @_Z13findCandidatePii(ptr noundef, i32 noundef) #0

; 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

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z15majorityElementPii(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %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
  %9 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %10 = load ptr, ptr %4, align 8, !tbaa !5
  %11 = load i32, ptr %5, align 4, !tbaa !9
  %12 = call noundef i32 @_Z13findCandidatePii(ptr noundef %10, i32 noundef %11)
  store i32 %12, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  store i32 0, ptr %7, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  store i32 0, ptr %8, align 4, !tbaa !9
  br label %13

13:                                               ; preds = %30, %2
  %14 = load i32, ptr %8, align 4, !tbaa !9
  %15 = load i32, ptr %5, align 4, !tbaa !9
  %16 = icmp slt i32 %14, %15
  br i1 %16, label %18, label %17

17:                                               ; preds = %13
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  br label %33

18:                                               ; preds = %13
  %19 = load ptr, ptr %4, align 8, !tbaa !5
  %20 = load i32, ptr %8, align 4, !tbaa !9
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds i32, ptr %19, i64 %21
  %23 = load i32, ptr %22, align 4, !tbaa !9
  %24 = load i32, ptr %6, align 4, !tbaa !9
  %25 = icmp eq i32 %23, %24
  br i1 %25, label %26, label %29

26:                                               ; preds = %18
  %27 = load i32, ptr %7, align 4, !tbaa !9
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %7, align 4, !tbaa !9
  br label %29

29:                                               ; preds = %26, %18
  br label %30

30:                                               ; preds = %29
  %31 = load i32, ptr %8, align 4, !tbaa !9
  %32 = add nsw i32 %31, 1
  store i32 %32, ptr %8, align 4, !tbaa !9
  br label %13, !llvm.loop !11

33:                                               ; preds = %17
  %34 = load i32, ptr %7, align 4, !tbaa !9
  %35 = load i32, ptr %5, align 4, !tbaa !9
  %36 = sdiv i32 %35, 2
  %37 = icmp sgt i32 %34, %36
  br i1 %37, label %38, label %40

38:                                               ; preds = %33
  %39 = load i32, ptr %6, align 4, !tbaa !9
  store i32 %39, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %41

40:                                               ; preds = %33
  store i32 -1, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %41

41:                                               ; preds = %40, %38
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %42 = load i32, ptr %3, align 4
  ret i32 %42
}

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 nounwind uwtable
declare dso_local noundef i32 @_Z13findCandidatePii(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z15majorityElementPii(ptr noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = tail call noundef i32 @_Z13findCandidatePii(ptr noundef %0, i32 noundef %1)
  %4 = icmp sgt i32 %1, 0
  br i1 %4, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %2
  %wide.trip.count = zext nneg i32 %1 to i64
  %min.iters.check = icmp ult i32 %1, 8
  br i1 %min.iters.check, label %.lr.ph.preheader20, label %vector.ph

.lr.ph.preheader20:                               ; preds = %middle.block, %.lr.ph.preheader
  %indvars.iv.ph = phi i64 [ 0, %.lr.ph.preheader ], [ %n.vec, %middle.block ]
  %.01215.ph = phi i32 [ 0, %.lr.ph.preheader ], [ %14, %middle.block ]
  br label %.lr.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %wide.trip.count, 2147483640
  %broadcast.splatinsert = insertelement <4 x i32> poison, i32 %3, i64 0
  %broadcast.splat = shufflevector <4 x i32> %broadcast.splatinsert, <4 x i32> poison, <4 x i32> zeroinitializer
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %vec.phi = phi <4 x i32> [ zeroinitializer, %vector.ph ], [ %11, %vector.body ]
  %vec.phi18 = phi <4 x i32> [ zeroinitializer, %vector.ph ], [ %12, %vector.body ]
  %5 = getelementptr inbounds i32, ptr %0, i64 %index
  %6 = getelementptr inbounds i8, ptr %5, i64 16
  %wide.load = load <4 x i32>, ptr %5, align 4, !tbaa !5
  %wide.load19 = load <4 x i32>, ptr %6, align 4, !tbaa !5
  %7 = icmp eq <4 x i32> %wide.load, %broadcast.splat
  %8 = icmp eq <4 x i32> %wide.load19, %broadcast.splat
  %9 = zext <4 x i1> %7 to <4 x i32>
  %10 = zext <4 x i1> %8 to <4 x i32>
  %11 = add <4 x i32> %vec.phi, %9
  %12 = add <4 x i32> %vec.phi18, %10
  %index.next = add nuw i64 %index, 8
  %13 = icmp eq i64 %index.next, %n.vec
  br i1 %13, label %middle.block, label %vector.body, !llvm.loop !9

middle.block:                                     ; preds = %vector.body
  %bin.rdx = add <4 x i32> %12, %11
  %14 = tail call i32 @llvm.vector.reduce.add.v4i32(<4 x i32> %bin.rdx)
  %cmp.n = icmp eq i64 %n.vec, %wide.trip.count
  br i1 %cmp.n, label %._crit_edge, label %.lr.ph.preheader20

._crit_edge:                                      ; preds = %.lr.ph, %middle.block, %2
  %.012.lcssa = phi i32 [ 0, %2 ], [ %14, %middle.block ], [ %spec.select, %.lr.ph ]
  %15 = sdiv i32 %1, 2
  %16 = icmp sgt i32 %.012.lcssa, %15
  %. = select i1 %16, i32 %3, i32 -1
  ret i32 %.

.lr.ph:                                           ; preds = %.lr.ph.preheader20, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ %indvars.iv.ph, %.lr.ph.preheader20 ]
  %.01215 = phi i32 [ %spec.select, %.lr.ph ], [ %.01215.ph, %.lr.ph.preheader20 ]
  %17 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %18 = load i32, ptr %17, align 4, !tbaa !5
  %19 = icmp eq i32 %18, %3
  %20 = zext i1 %19 to i32
  %spec.select = add nuw nsw i32 %.01215, %20
  %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 !13
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.vector.reduce.add.v4i32(<4 x i32>) #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 speculatable willreturn memory(none) }

!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, !11, !12}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!"llvm.loop.isvectorized", i32 1}
!12 = !{!"llvm.loop.unroll.runtime.disable"}
!13 = distinct !{!13, !10, !12, !11}


; Effective O3 passes: GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopLoadEliminationPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,LoopVectorizePass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass