; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C/Algorithms/Backtracking (N-Queen)

; 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: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind uwtable
declare dso_local zeroext i1 @isSafe(ptr noundef, i32 noundef, i32 noundef) #1

; Function Attrs: nounwind uwtable
define dso_local zeroext i1 @solveNQUtil(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca i1, align 1
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  %8 = load i32, ptr %5, align 4, !tbaa !9
  %9 = icmp sge i32 %8, 4
  br i1 %9, label %10, label %11

10:                                               ; preds = %2
  store i1 true, ptr %3, align 1
  br label %49

11:                                               ; preds = %2
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  store i32 0, ptr %6, align 4, !tbaa !9
  br label %12

12:                                               ; preds = %43, %11
  %13 = load i32, ptr %6, align 4, !tbaa !9
  %14 = icmp slt i32 %13, 4
  br i1 %14, label %16, label %15

15:                                               ; preds = %12
  store i32 2, ptr %7, align 4
  br label %46

16:                                               ; preds = %12
  %17 = load ptr, ptr %4, align 8, !tbaa !5
  %18 = load i32, ptr %6, align 4, !tbaa !9
  %19 = load i32, ptr %5, align 4, !tbaa !9
  %20 = call zeroext i1 @isSafe(ptr noundef %17, i32 noundef %18, i32 noundef %19)
  br i1 %20, label %21, label %42

21:                                               ; preds = %16
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = load i32, ptr %6, align 4, !tbaa !9
  %24 = sext i32 %23 to i64
  %25 = getelementptr inbounds [4 x i32], ptr %22, i64 %24
  %26 = load i32, ptr %5, align 4, !tbaa !9
  %27 = sext i32 %26 to i64
  %28 = getelementptr inbounds [4 x i32], ptr %25, i64 0, i64 %27
  store i32 1, ptr %28, align 4, !tbaa !9
  %29 = load ptr, ptr %4, align 8, !tbaa !5
  %30 = load i32, ptr %5, align 4, !tbaa !9
  %31 = add nsw i32 %30, 1
  %32 = call zeroext i1 @solveNQUtil(ptr noundef %29, i32 noundef %31)
  br i1 %32, label %33, label %34

33:                                               ; preds = %21
  store i1 true, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %46

34:                                               ; preds = %21
  %35 = load ptr, ptr %4, align 8, !tbaa !5
  %36 = load i32, ptr %6, align 4, !tbaa !9
  %37 = sext i32 %36 to i64
  %38 = getelementptr inbounds [4 x i32], ptr %35, i64 %37
  %39 = load i32, ptr %5, align 4, !tbaa !9
  %40 = sext i32 %39 to i64
  %41 = getelementptr inbounds [4 x i32], ptr %38, i64 0, i64 %40
  store i32 0, ptr %41, align 4, !tbaa !9
  br label %42

42:                                               ; preds = %34, %16
  br label %43

43:                                               ; preds = %42
  %44 = load i32, ptr %6, align 4, !tbaa !9
  %45 = add nsw i32 %44, 1
  store i32 %45, ptr %6, align 4, !tbaa !9
  br label %12, !llvm.loop !11

46:                                               ; preds = %33, %15
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %47 = load i32, ptr %7, align 4
  switch i32 %47, label %51 [
    i32 2, label %48
    i32 1, label %49
  ]

48:                                               ; preds = %46
  store i1 false, ptr %3, align 1
  br label %49

49:                                               ; preds = %48, %46, %10
  %50 = load i1, ptr %3, align 1
  ret i1 %50

51:                                               ; preds = %46
  unreachable
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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/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: nounwind uwtable
declare dso_local zeroext i1 @isSafe(ptr noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local noundef zeroext i1 @solveNQUtil(ptr noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i32 %1, 3
  br i1 %3, label %.loopexit, label %.preheader

.preheader:                                       ; preds = %2
  %4 = sext i32 %1 to i64
  %5 = add nsw i32 %1, 1
  %6 = tail call zeroext i1 @isSafe(ptr noundef %0, i32 noundef 0, i32 noundef %1)
  br i1 %6, label %7, label %11

7:                                                ; preds = %.preheader
  %8 = getelementptr inbounds [4 x i32], ptr %0, i64 0, i64 %4
  store i32 1, ptr %8, align 4, !tbaa !5
  %9 = tail call zeroext i1 @solveNQUtil(ptr noundef %0, i32 noundef %5)
  br i1 %9, label %.loopexit, label %10

10:                                               ; preds = %7
  store i32 0, ptr %8, align 4, !tbaa !5
  br label %11

11:                                               ; preds = %.preheader, %10
  %12 = tail call zeroext i1 @isSafe(ptr noundef %0, i32 noundef 1, i32 noundef %1)
  br i1 %12, label %13, label %17

13:                                               ; preds = %11
  %14 = getelementptr inbounds [4 x i32], ptr %0, i64 1, i64 %4
  store i32 1, ptr %14, align 4, !tbaa !5
  %15 = tail call zeroext i1 @solveNQUtil(ptr noundef %0, i32 noundef %5)
  br i1 %15, label %.loopexit, label %16

16:                                               ; preds = %13
  store i32 0, ptr %14, align 4, !tbaa !5
  br label %17

17:                                               ; preds = %16, %11
  %18 = tail call zeroext i1 @isSafe(ptr noundef %0, i32 noundef 2, i32 noundef %1)
  br i1 %18, label %19, label %23

19:                                               ; preds = %17
  %20 = getelementptr inbounds [4 x i32], ptr %0, i64 2, i64 %4
  store i32 1, ptr %20, align 4, !tbaa !5
  %21 = tail call zeroext i1 @solveNQUtil(ptr noundef %0, i32 noundef %5)
  br i1 %21, label %.loopexit, label %22

22:                                               ; preds = %19
  store i32 0, ptr %20, align 4, !tbaa !5
  br label %23

23:                                               ; preds = %22, %17
  %24 = tail call zeroext i1 @isSafe(ptr noundef %0, i32 noundef 3, i32 noundef %1)
  br i1 %24, label %25, label %.loopexit

25:                                               ; preds = %23
  %26 = getelementptr inbounds [4 x i32], ptr %0, i64 3, i64 %4
  store i32 1, ptr %26, align 4, !tbaa !5
  %27 = tail call zeroext i1 @solveNQUtil(ptr noundef %0, i32 noundef %5)
  br i1 %27, label %.loopexit, label %28

28:                                               ; preds = %25
  store i32 0, ptr %26, align 4, !tbaa !5
  br label %.loopexit

.loopexit:                                        ; preds = %7, %13, %19, %25, %28, %23, %2
  %.1 = phi i1 [ true, %2 ], [ true, %7 ], [ true, %13 ], [ true, %19 ], [ true, %25 ], [ false, %28 ], [ false, %23 ]
  ret i1 %.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" }

!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"}


; Effective O3 passes: ConstraintEliminationPass,CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LICMPass,LoopRotatePass,LoopSimplifyPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass