; LLVM IR from sachuverma/DataStructures-Algorithms :: DSA Crack Sheet/solutions/Allocate minimum number of pages.ll (Z9findPagesPiii)

; 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 zeroext i1 @_Z13canDistrubutePiiii(ptr noundef, i32 noundef, i32 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 @_Z9findPagesPiii(ptr noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  %11 = alloca i32, align 4
  %12 = alloca i32, align 4
  %13 = alloca i32, align 4
  store ptr %0, ptr %5, align 8, !tbaa !5
  store i32 %1, ptr %6, align 4, !tbaa !9
  store i32 %2, 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
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #2
  store i32 0, ptr %9, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #2
  store i32 0, ptr %10, align 4, !tbaa !9
  br label %14

14:                                               ; preds = %27, %3
  %15 = load i32, ptr %10, align 4, !tbaa !9
  %16 = load i32, ptr %6, align 4, !tbaa !9
  %17 = icmp slt i32 %15, %16
  br i1 %17, label %19, label %18

18:                                               ; preds = %14
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #2
  br label %30

19:                                               ; preds = %14
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = load i32, ptr %10, align 4, !tbaa !9
  %22 = sext i32 %21 to i64
  %23 = getelementptr inbounds i32, ptr %20, i64 %22
  %24 = load i32, ptr %23, align 4, !tbaa !9
  %25 = load i32, ptr %9, align 4, !tbaa !9
  %26 = add nsw i32 %25, %24
  store i32 %26, ptr %9, align 4, !tbaa !9
  br label %27

27:                                               ; preds = %19
  %28 = load i32, ptr %10, align 4, !tbaa !9
  %29 = add nsw i32 %28, 1
  store i32 %29, ptr %10, align 4, !tbaa !9
  br label %14, !llvm.loop !11

30:                                               ; preds = %18
  call void @llvm.lifetime.start.p0(i64 4, ptr %11) #2
  store i32 0, ptr %11, align 4, !tbaa !9
  %31 = load i32, ptr %6, align 4, !tbaa !9
  %32 = load i32, ptr %7, align 4, !tbaa !9
  %33 = icmp slt i32 %31, %32
  br i1 %33, label %34, label %35

34:                                               ; preds = %30
  store i32 -1, ptr %4, align 4
  store i32 1, ptr %12, align 4
  br label %60

35:                                               ; preds = %30
  br label %36

36:                                               ; preds = %57, %35
  %37 = load i32, ptr %11, align 4, !tbaa !9
  %38 = load i32, ptr %9, align 4, !tbaa !9
  %39 = icmp sle i32 %37, %38
  br i1 %39, label %40, label %58

40:                                               ; preds = %36
  call void @llvm.lifetime.start.p0(i64 4, ptr %13) #2
  %41 = load i32, ptr %11, align 4, !tbaa !9
  %42 = load i32, ptr %9, align 4, !tbaa !9
  %43 = add nsw i32 %41, %42
  %44 = sdiv i32 %43, 2
  store i32 %44, ptr %13, align 4, !tbaa !9
  %45 = load ptr, ptr %5, align 8, !tbaa !5
  %46 = load i32, ptr %6, align 4, !tbaa !9
  %47 = load i32, ptr %7, align 4, !tbaa !9
  %48 = load i32, ptr %13, align 4, !tbaa !9
  %49 = call noundef zeroext i1 @_Z13canDistrubutePiiii(ptr noundef %45, i32 noundef %46, i32 noundef %47, i32 noundef %48)
  br i1 %49, label %50, label %54

50:                                               ; preds = %40
  %51 = load i32, ptr %13, align 4, !tbaa !9
  store i32 %51, ptr %8, align 4, !tbaa !9
  %52 = load i32, ptr %13, align 4, !tbaa !9
  %53 = sub nsw i32 %52, 1
  store i32 %53, ptr %9, align 4, !tbaa !9
  br label %57

54:                                               ; preds = %40
  %55 = load i32, ptr %13, align 4, !tbaa !9
  %56 = add nsw i32 %55, 1
  store i32 %56, ptr %11, align 4, !tbaa !9
  br label %57

57:                                               ; preds = %54, %50
  call void @llvm.lifetime.end.p0(i64 4, ptr %13) #2
  br label %36, !llvm.loop !13

58:                                               ; preds = %36
  %59 = load i32, ptr %8, align 4, !tbaa !9
  store i32 %59, ptr %4, align 4
  store i32 1, ptr %12, align 4
  br label %60

60:                                               ; preds = %58, %34
  call void @llvm.lifetime.end.p0(i64 4, ptr %11) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  %61 = load i32, ptr %4, align 4
  ret i32 %61
}

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"}
!13 = distinct !{!13, !12}


; 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 zeroext i1 @_Z13canDistrubutePiiii(ptr noundef, i32 noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef range(i32 -1, 1073741824) i32 @_Z9findPagesPiii(ptr noundef %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.thread

.lr.ph.preheader:                                 ; preds = %3
  %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.preheader43, label %vector.ph

.lr.ph.preheader43:                               ; preds = %middle.block, %.lr.ph.preheader
  %indvars.iv.ph = phi i64 [ 0, %.lr.ph.preheader ], [ %n.vec, %middle.block ]
  %.02227.ph = phi i32 [ 0, %.lr.ph.preheader ], [ %10, %middle.block ]
  br label %.lr.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %wide.trip.count, 2147483640
  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 ], [ %7, %vector.body ]
  %vec.phi41 = phi <4 x i32> [ zeroinitializer, %vector.ph ], [ %8, %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.load42 = load <4 x i32>, ptr %6, align 4, !tbaa !5
  %7 = add <4 x i32> %wide.load, %vec.phi
  %8 = add <4 x i32> %wide.load42, %vec.phi41
  %index.next = add nuw i64 %index, 8
  %9 = icmp eq i64 %index.next, %n.vec
  br i1 %9, label %middle.block, label %vector.body, !llvm.loop !9

middle.block:                                     ; preds = %vector.body
  %bin.rdx = add <4 x i32> %8, %7
  %10 = 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.preheader43

._crit_edge:                                      ; preds = %.lr.ph, %middle.block
  %.lcssa = phi i32 [ %10, %middle.block ], [ %15, %.lr.ph ]
  %11 = icmp slt i32 %1, %2
  br i1 %11, label %.loopexit, label %.preheader

._crit_edge.thread:                               ; preds = %3
  %12 = icmp slt i32 %1, %2
  br i1 %12, label %.loopexit, label %.lr.ph33.preheader

.preheader:                                       ; preds = %._crit_edge
  %.not29 = icmp slt i32 %.lcssa, 0
  br i1 %.not29, label %.loopexit, label %.lr.ph33.preheader

.lr.ph33.preheader:                               ; preds = %._crit_edge.thread, %.preheader
  %.12331.ph = phi i32 [ %.lcssa, %.preheader ], [ 0, %._crit_edge.thread ]
  br label %.lr.ph33

.lr.ph:                                           ; preds = %.lr.ph.preheader43, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ %indvars.iv.ph, %.lr.ph.preheader43 ]
  %.02227 = phi i32 [ %15, %.lr.ph ], [ %.02227.ph, %.lr.ph.preheader43 ]
  %13 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %14 = load i32, ptr %13, align 4, !tbaa !5
  %15 = add nsw i32 %14, %.02227
  %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

.lr.ph33:                                         ; preds = %.lr.ph33.preheader, %.lr.ph33
  %.02032 = phi i32 [ %.1, %.lr.ph33 ], [ 0, %.lr.ph33.preheader ]
  %.12331 = phi i32 [ %.2, %.lr.ph33 ], [ %.12331.ph, %.lr.ph33.preheader ]
  %.02430 = phi i32 [ %.125, %.lr.ph33 ], [ 0, %.lr.ph33.preheader ]
  %16 = add nuw nsw i32 %.02032, %.12331
  %17 = lshr i32 %16, 1
  %18 = tail call noundef zeroext i1 @_Z13canDistrubutePiiii(ptr noundef %0, i32 noundef %1, i32 noundef %2, i32 noundef %17)
  %19 = add nsw i32 %17, -1
  %20 = add nuw nsw i32 %17, 1
  %.125 = select i1 %18, i32 %17, i32 %.02430
  %.2 = select i1 %18, i32 %19, i32 %.12331
  %.1 = select i1 %18, i32 %.02032, i32 %20
  %.not = icmp sgt i32 %.1, %.2
  br i1 %.not, label %.loopexit, label %.lr.ph33, !llvm.loop !14

.loopexit:                                        ; preds = %.lr.ph33, %._crit_edge.thread, %.preheader, %._crit_edge
  %.0 = phi i32 [ -1, %._crit_edge ], [ 0, %.preheader ], [ -1, %._crit_edge.thread ], [ %.125, %.lr.ph33 ]
  ret i32 %.0
}

; 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}
!14 = distinct !{!14, !10}


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