; LLVM IR from amritansh22/Data-Structures-and-Algorithms-in-cpp :: square_root.ll (Z9floorSqrti)

; 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 @_Z9floorSqrti(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  store i32 1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  %9 = load i32, ptr %3, align 4, !tbaa !5
  store i32 %9, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  br label %10

10:                                               ; preds = %43, %1
  %11 = load i32, ptr %4, align 4, !tbaa !5
  %12 = load i32, ptr %5, align 4, !tbaa !5
  %13 = icmp sle i32 %11, %12
  br i1 %13, label %14, label %44

14:                                               ; preds = %10
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  %15 = load i32, ptr %4, align 4, !tbaa !5
  %16 = load i32, ptr %5, align 4, !tbaa !5
  %17 = add nsw i32 %15, %16
  %18 = sdiv i32 %17, 2
  store i32 %18, ptr %7, align 4, !tbaa !5
  %19 = load i32, ptr %7, align 4, !tbaa !5
  %20 = load i32, ptr %7, align 4, !tbaa !5
  %21 = mul nsw i32 %19, %20
  %22 = load i32, ptr %3, align 4, !tbaa !5
  %23 = icmp eq i32 %21, %22
  br i1 %23, label %24, label %26

24:                                               ; preds = %14
  %25 = load i32, ptr %7, align 4, !tbaa !5
  store i32 %25, ptr %2, align 4
  store i32 1, ptr %8, align 4
  br label %41

26:                                               ; preds = %14
  %27 = load i32, ptr %7, align 4, !tbaa !5
  %28 = load i32, ptr %7, align 4, !tbaa !5
  %29 = mul nsw i32 %27, %28
  %30 = load i32, ptr %3, align 4, !tbaa !5
  %31 = icmp sgt i32 %29, %30
  br i1 %31, label %32, label %35

32:                                               ; preds = %26
  %33 = load i32, ptr %7, align 4, !tbaa !5
  %34 = sub nsw i32 %33, 1
  store i32 %34, ptr %5, align 4, !tbaa !5
  br label %39

35:                                               ; preds = %26
  %36 = load i32, ptr %7, align 4, !tbaa !5
  %37 = add nsw i32 %36, 1
  store i32 %37, ptr %4, align 4, !tbaa !5
  %38 = load i32, ptr %7, align 4, !tbaa !5
  store i32 %38, ptr %6, align 4, !tbaa !5
  br label %39

39:                                               ; preds = %35, %32
  br label %40

40:                                               ; preds = %39
  store i32 0, ptr %8, align 4
  br label %41

41:                                               ; preds = %40, %24
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  %42 = load i32, ptr %8, align 4
  switch i32 %42, label %46 [
    i32 0, label %43
  ]

43:                                               ; preds = %41
  br label %10, !llvm.loop !9

44:                                               ; preds = %10
  %45 = load i32, ptr %6, align 4, !tbaa !5
  store i32 %45, ptr %2, align 4
  store i32 1, ptr %8, align 4
  br label %46

46:                                               ; preds = %44, %41
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  %47 = load i32, ptr %2, align 4
  ret i32 %47
}

; 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"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(none) uwtable
define dso_local noundef i32 @_Z9floorSqrti(i32 noundef %0) local_unnamed_addr #0 {
  %.not35 = icmp sgt i32 %0, 0
  tail call void @llvm.assume(i1 %.not35)
  br label %.lr.ph

.lr.ph:                                           ; preds = %1, %5
  %.01938 = phi i32 [ %.120, %5 ], [ undef, %1 ]
  %.02237 = phi i32 [ %.123, %5 ], [ %0, %1 ]
  %.02536 = phi i32 [ %.126, %5 ], [ 1, %1 ]
  %2 = add nuw nsw i32 %.02237, %.02536
  %3 = lshr i32 %2, 1
  %4 = mul nuw nsw i32 %3, %3
  %.not30 = icmp eq i32 %4, %0
  br i1 %.not30, label %.thread, label %5

5:                                                ; preds = %.lr.ph
  %6 = icmp ugt i32 %4, %0
  %7 = add nsw i32 %3, -1
  %8 = add nuw nsw i32 %3, 1
  %.126 = select i1 %6, i32 %.02536, i32 %8
  %.123 = select i1 %6, i32 %7, i32 %.02237
  %.120 = select i1 %6, i32 %.01938, i32 %3
  %.not = icmp sgt i32 %.126, %.123
  br i1 %.not, label %.thread, label %.lr.ph

.thread:                                          ; preds = %5, %.lr.ph
  %.2 = phi i32 [ %3, %.lr.ph ], [ %.120, %5 ]
  ret i32 %.2
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(inaccessiblemem: write)
declare void @llvm.assume(i1 noundef) #1

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(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" }
attributes #1 = { nocallback nofree nosync nounwind willreturn memory(inaccessiblemem: write) }

!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)"}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass