; LLVM IR from 6leetcode/6leetcode :: questions/Algorithms/0231. Power of Two (c1)

; 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: nounwind uwtable
define dso_local zeroext i1 @isPowerOfTwo(i32 noundef %0) #0 {
  %2 = alloca i1, align 1
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = 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 0, ptr %4, align 4, !tbaa !5
  br label %6

6:                                                ; preds = %21, %1
  %7 = load i32, ptr %3, align 4, !tbaa !5
  %8 = icmp sgt i32 %7, 0
  br i1 %8, label %9, label %24

9:                                                ; preds = %6
  %10 = load i32, ptr %3, align 4, !tbaa !5
  %11 = and i32 %10, 1
  %12 = icmp ne i32 %11, 0
  br i1 %12, label %13, label %20

13:                                               ; preds = %9
  %14 = load i32, ptr %4, align 4, !tbaa !5
  %15 = add nsw i32 %14, 1
  store i32 %15, ptr %4, align 4, !tbaa !5
  %16 = load i32, ptr %4, align 4, !tbaa !5
  %17 = icmp sgt i32 %16, 1
  br i1 %17, label %18, label %19

18:                                               ; preds = %13
  store i1 false, ptr %2, align 1
  store i32 1, ptr %5, align 4
  br label %27

19:                                               ; preds = %13
  br label %20

20:                                               ; preds = %19, %9
  br label %21

21:                                               ; preds = %20
  %22 = load i32, ptr %3, align 4, !tbaa !5
  %23 = ashr i32 %22, 1
  store i32 %23, ptr %3, align 4, !tbaa !5
  br label %6, !llvm.loop !9

24:                                               ; preds = %6
  %25 = load i32, ptr %4, align 4, !tbaa !5
  %26 = icmp eq i32 %25, 1
  store i1 %26, ptr %2, align 1
  store i32 1, ptr %5, align 4
  br label %27

27:                                               ; preds = %24, %18
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  %28 = load i1, ptr %2, align 1
  ret i1 %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 = { 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/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: nofree norecurse nosync nounwind memory(none) uwtable
define dso_local zeroext i1 @isPowerOfTwo(i32 noundef %0) local_unnamed_addr #0 {
  %2 = icmp sgt i32 %0, 0
  br i1 %2, label %.lr.ph, label %.loopexit

.lr.ph:                                           ; preds = %1, %6
  %.011 = phi i32 [ %.1, %6 ], [ 0, %1 ]
  %.0610 = phi i32 [ %7, %6 ], [ %0, %1 ]
  %3 = and i32 %.0610, 1
  %.not = icmp eq i32 %3, 0
  br i1 %.not, label %6, label %4

4:                                                ; preds = %.lr.ph
  %5 = icmp sgt i32 %.011, 0
  br i1 %5, label %.loopexit, label %6

6:                                                ; preds = %.lr.ph, %4
  %.1 = phi i32 [ 1, %4 ], [ %.011, %.lr.ph ]
  %7 = lshr i32 %.0610, 1
  %.not12 = icmp ult i32 %.0610, 2
  br i1 %.not12, label %._crit_edge.loopexit, label %.lr.ph, !llvm.loop !5

._crit_edge.loopexit:                             ; preds = %6
  %8 = icmp eq i32 %.1, 1
  br label %.loopexit

.loopexit:                                        ; preds = %4, %1, %._crit_edge.loopexit
  %.07 = phi i1 [ false, %1 ], [ %8, %._crit_edge.loopexit ], [ false, %4 ]
  ret i1 %.07
}

attributes #0 = { nofree norecurse nosync nounwind 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" }

!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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GVNPass,GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass