; LLVM IR from Leet-Us-Code/DSA-A-Z-Practice :: Sid's Levels/Level - 2/Bitmasking/Finding Square.ll (Z6squarei)

; 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 uwtable
define dso_local noundef i32 @_Z6squarei(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  %6 = load i32, ptr %3, align 4, !tbaa !5
  %7 = icmp eq i32 %6, 0
  br i1 %7, label %8, label %9

8:                                                ; preds = %1
  store i32 0, ptr %2, align 4
  br label %34

9:                                                ; preds = %1
  %10 = load i32, ptr %3, align 4, !tbaa !5
  %11 = icmp slt i32 %10, 0
  br i1 %11, label %12, label %15

12:                                               ; preds = %9
  %13 = load i32, ptr %3, align 4, !tbaa !5
  %14 = sub nsw i32 0, %13
  store i32 %14, ptr %3, align 4, !tbaa !5
  br label %15

15:                                               ; preds = %12, %9
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  %16 = load i32, ptr %3, align 4, !tbaa !5
  %17 = ashr i32 %16, 1
  store i32 %17, ptr %4, align 4, !tbaa !5
  %18 = load i32, ptr %3, align 4, !tbaa !5
  %19 = and i32 %18, 1
  %20 = icmp ne i32 %19, 0
  br i1 %20, label %21, label %29

21:                                               ; preds = %15
  %22 = load i32, ptr %4, align 4, !tbaa !5
  %23 = call noundef i32 @_Z6squarei(i32 noundef %22)
  %24 = shl i32 %23, 2
  %25 = load i32, ptr %4, align 4, !tbaa !5
  %26 = shl i32 %25, 2
  %27 = add nsw i32 %24, %26
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %2, align 4
  store i32 1, ptr %5, align 4
  br label %33

29:                                               ; preds = %15
  %30 = load i32, ptr %4, align 4, !tbaa !5
  %31 = call noundef i32 @_Z6squarei(i32 noundef %30)
  %32 = shl i32 %31, 2
  store i32 %32, ptr %2, align 4
  store i32 1, ptr %5, align 4
  br label %33

33:                                               ; preds = %29, %21
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %34

34:                                               ; preds = %33, %8
  %35 = load i32, ptr %2, align 4
  ret i32 %35
}

; 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 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"}


; 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 nosync nounwind willreturn memory(none) uwtable
define dso_local noundef i32 @_Z6squarei(i32 noundef %0) local_unnamed_addr #0 {
  %2 = icmp eq i32 %0, 0
  br i1 %2, label %common.ret, label %3

3:                                                ; preds = %1
  %spec.select = tail call i32 @llvm.abs.i32(i32 %0, i1 true)
  %4 = lshr i32 %spec.select, 1
  %5 = and i32 %spec.select, 1
  %.not = icmp eq i32 %5, 0
  %6 = tail call noundef i32 @_Z6squarei(i32 noundef %4)
  br i1 %.not, label %11, label %7

common.ret:                                       ; preds = %1, %11, %7
  %common.ret.op = phi i32 [ %10, %7 ], [ %12, %11 ], [ 0, %1 ]
  ret i32 %common.ret.op

7:                                                ; preds = %3
  %8 = add i32 %6, %4
  %9 = shl i32 %8, 2
  %10 = or disjoint i32 %9, 1
  br label %common.ret

11:                                               ; preds = %3
  %12 = shl i32 %6, 2
  br label %common.ret
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.abs.i32(i32, i1 immarg) #1

attributes #0 = { mustprogress nofree 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 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)"}


; Effective O3 passes: GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass