; LLVM IR from sachuverma/DataStructures-Algorithms :: DSA Crack Sheet/solutions/Majority Element.ll (Z13findCandidatePii)

; 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 @_Z13findCandidatePii(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 0, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  store i32 1, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  store i32 1, ptr %7, align 4, !tbaa !9
  br label %8

8:                                                ; preds = %37, %2
  %9 = load i32, ptr %7, align 4, !tbaa !9
  %10 = load i32, ptr %4, align 4, !tbaa !9
  %11 = icmp slt i32 %9, %10
  br i1 %11, label %13, label %12

12:                                               ; preds = %8
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  br label %40

13:                                               ; preds = %8
  %14 = load ptr, ptr %3, align 8, !tbaa !5
  %15 = load i32, ptr %5, 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 ptr, ptr %3, align 8, !tbaa !5
  %20 = load i32, ptr %7, 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 = icmp eq i32 %18, %23
  br i1 %24, label %25, label %28

25:                                               ; preds = %13
  %26 = load i32, ptr %6, align 4, !tbaa !9
  %27 = add nsw i32 %26, 1
  store i32 %27, ptr %6, align 4, !tbaa !9
  br label %31

28:                                               ; preds = %13
  %29 = load i32, ptr %6, align 4, !tbaa !9
  %30 = add nsw i32 %29, -1
  store i32 %30, ptr %6, align 4, !tbaa !9
  br label %31

31:                                               ; preds = %28, %25
  %32 = load i32, ptr %6, align 4, !tbaa !9
  %33 = icmp eq i32 %32, 0
  br i1 %33, label %34, label %36

34:                                               ; preds = %31
  %35 = load i32, ptr %7, align 4, !tbaa !9
  store i32 %35, ptr %5, align 4, !tbaa !9
  store i32 1, ptr %6, align 4, !tbaa !9
  br label %36

36:                                               ; preds = %34, %31
  br label %37

37:                                               ; preds = %36
  %38 = load i32, ptr %7, align 4, !tbaa !9
  %39 = add nsw i32 %38, 1
  store i32 %39, ptr %7, align 4, !tbaa !9
  br label %8, !llvm.loop !11

40:                                               ; preds = %12
  %41 = load ptr, ptr %3, align 8, !tbaa !5
  %42 = load i32, ptr %5, align 4, !tbaa !9
  %43 = sext i32 %42 to i64
  %44 = getelementptr inbounds i32, ptr %41, i64 %43
  %45 = load i32, ptr %44, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i32 %45
}

; 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 @_Z13findCandidatePii(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i32 %1, 1
  br i1 %3, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %2
  %wide.trip.count = zext nneg i32 %1 to i64
  %4 = add nsw i64 %wide.trip.count, -1
  %xtraiter = and i64 %4, 1
  %5 = icmp eq i32 %1, 2
  br i1 %5, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i64 %4, -2
  br label %.lr.ph

._crit_edge.loopexit.unr-lcssa:                   ; preds = %.lr.ph, %.lr.ph.preheader
  %.114.lcssa.ph = phi i32 [ poison, %.lr.ph.preheader ], [ %.114.1, %.lr.ph ]
  %indvars.iv.unr = phi i64 [ 1, %.lr.ph.preheader ], [ %indvars.iv.next.1, %.lr.ph ]
  %.01216.unr = phi i32 [ 1, %.lr.ph.preheader ], [ %.2.1, %.lr.ph ]
  %.01315.unr = phi i32 [ 0, %.lr.ph.preheader ], [ %.114.1, %.lr.ph ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge.loopexit, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa
  %6 = sext i32 %.01315.unr to i64
  %7 = getelementptr inbounds i32, ptr %0, i64 %6
  %8 = load i32, ptr %7, align 4, !tbaa !5
  %9 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv.unr
  %10 = load i32, ptr %9, align 4, !tbaa !5
  %11 = icmp eq i32 %8, %10
  %.1.v.epil = select i1 %11, i32 1, i32 -1
  %.1.epil = sub i32 0, %.01216.unr
  %12 = icmp eq i32 %.1.v.epil, %.1.epil
  %13 = trunc nuw nsw i64 %indvars.iv.unr to i32
  %.114.epil = select i1 %12, i32 %13, i32 %.01315.unr
  br label %._crit_edge.loopexit

._crit_edge.loopexit:                             ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil
  %.114.lcssa = phi i32 [ %.114.lcssa.ph, %._crit_edge.loopexit.unr-lcssa ], [ %.114.epil, %.lr.ph.epil ]
  %14 = sext i32 %.114.lcssa to i64
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %2
  %.013.lcssa = phi i64 [ 0, %2 ], [ %14, %._crit_edge.loopexit ]
  %15 = getelementptr inbounds i32, ptr %0, i64 %.013.lcssa
  %16 = load i32, ptr %15, align 4, !tbaa !5
  ret i32 %16

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader.new
  %indvars.iv = phi i64 [ 1, %.lr.ph.preheader.new ], [ %indvars.iv.next.1, %.lr.ph ]
  %.01216 = phi i32 [ 1, %.lr.ph.preheader.new ], [ %.2.1, %.lr.ph ]
  %.01315 = phi i32 [ 0, %.lr.ph.preheader.new ], [ %.114.1, %.lr.ph ]
  %niter = phi i64 [ 0, %.lr.ph.preheader.new ], [ %niter.next.1, %.lr.ph ]
  %17 = sext i32 %.01315 to i64
  %18 = getelementptr inbounds i32, ptr %0, i64 %17
  %19 = load i32, ptr %18, align 4, !tbaa !5
  %20 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %21 = load i32, ptr %20, align 4, !tbaa !5
  %22 = icmp eq i32 %19, %21
  %.1.v = select i1 %22, i32 1, i32 -1
  %.1 = add nsw i32 %.1.v, %.01216
  %23 = icmp eq i32 %.1, 0
  %24 = trunc nuw nsw i64 %indvars.iv to i32
  %.114 = select i1 %23, i32 %24, i32 %.01315
  %.2 = tail call i32 @llvm.umax.i32(i32 %.1, i32 1)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %25 = sext i32 %.114 to i64
  %26 = getelementptr inbounds i32, ptr %0, i64 %25
  %27 = load i32, ptr %26, align 4, !tbaa !5
  %28 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv.next
  %29 = load i32, ptr %28, align 4, !tbaa !5
  %30 = icmp eq i32 %27, %29
  %.1.v.1 = select i1 %30, i32 1, i32 -1
  %.1.1 = add nsw i32 %.1.v.1, %.2
  %31 = icmp eq i32 %.1.1, 0
  %32 = trunc nuw nsw i64 %indvars.iv.next to i32
  %.114.1 = select i1 %31, i32 %32, i32 %.114
  %.2.1 = tail call i32 @llvm.umax.i32(i32 %.1.1, i32 1)
  %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv, 2
  %niter.next.1 = add i64 %niter, 2
  %niter.ncmp.1 = icmp eq i64 %niter.next.1, %unroll_iter
  br i1 %niter.ncmp.1, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !9
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.umax.i32(i32, i32) #1

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" }
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}
!10 = !{!"llvm.loop.mustprogress"}


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