; LLVM IR from Muhammad-Magdi/problem-solving :: Backtracking (750 - 8 Queens Chess Problem)

; 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"

@t = external dso_local global i32, align 4
@a = external dso_local global i32, align 4
@b = external dso_local global i32, align 4
@.str.3 = external hidden unnamed_addr constant [1 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [43 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [6 x i8], align 1

declare i32 @puts(ptr noundef) #0

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z5solvei(i32 noundef) #1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z4initv() #2

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #3 {
  %1 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %2 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.4, ptr noundef @t)
  br label %3

3:                                                ; preds = %14, %0
  %4 = load i32, ptr @t, align 4, !tbaa !5
  %5 = add nsw i32 %4, -1
  store i32 %5, ptr @t, align 4, !tbaa !5
  %6 = icmp ne i32 %4, 0
  br i1 %6, label %7, label %15

7:                                                ; preds = %3
  %8 = call i32 @puts(ptr noundef @.str.5)
  %9 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.6, ptr noundef @a, ptr noundef @b)
  call void @_Z4initv()
  call void @_Z5solvei(i32 noundef 1)
  %10 = load i32, ptr @t, align 4, !tbaa !5
  %11 = icmp ne i32 %10, 0
  br i1 %11, label %12, label %14

12:                                               ; preds = %7
  %13 = call i32 @puts(ptr noundef @.str.3)
  br label %14

14:                                               ; preds = %12, %7
  br label %3, !llvm.loop !9

15:                                               ; preds = %3
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #0

attributes #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 = { 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 #2 = { 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 #3 = { mustprogress norecurse 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++ 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"

@t = external dso_local global i32, align 4
@a = external dso_local global i32, align 4
@b = external dso_local global i32, align 4
@.str.3 = external hidden unnamed_addr constant [1 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [43 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [6 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @puts(ptr nocapture noundef readonly) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z5solvei(i32 noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z4initv() local_unnamed_addr #2

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #3 {
  %1 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.4, ptr noundef nonnull @t)
  %2 = load i32, ptr @t, align 4, !tbaa !5
  %3 = add nsw i32 %2, -1
  store i32 %3, ptr @t, align 4, !tbaa !5
  %.not2 = icmp eq i32 %2, 0
  br i1 %.not2, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %7
  %4 = tail call i32 @puts(ptr noundef nonnull dereferenceable(1) @.str.5)
  %5 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.6, ptr noundef nonnull @a, ptr noundef nonnull @b)
  tail call void @_Z4initv()
  tail call void @_Z5solvei(i32 noundef 1)
  %6 = load i32, ptr @t, align 4, !tbaa !5
  %.not1 = icmp eq i32 %6, 0
  br i1 %.not1, label %.thread, label %7

.thread:                                          ; preds = %.lr.ph
  store i32 -1, ptr @t, align 4, !tbaa !5
  br label %._crit_edge

7:                                                ; preds = %.lr.ph
  %8 = tail call i32 @puts(ptr noundef nonnull dereferenceable(1) @.str.3)
  %.pre = load i32, ptr @t, align 4, !tbaa !5
  %9 = add nsw i32 %.pre, -1
  store i32 %9, ptr @t, align 4, !tbaa !5
  %.not = icmp eq i32 %.pre, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

._crit_edge:                                      ; preds = %7, %.thread, %0
  ret i32 0
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

attributes #0 = { nofree nounwind "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 = { 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 #2 = { 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 #3 = { mustprogress norecurse 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++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass