; LLVM IR from begeekmyfriend/leetcode :: 0089_gray_code (gray_code)

; 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"

@stderr = external global ptr, align 8
@.str = external hidden unnamed_addr constant [17 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local ptr @grayCode(i32 noundef, ptr noundef) #0

; 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

; Function Attrs: nounwind uwtable
define dso_local i32 @main(i32 noundef %0, ptr noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca ptr, align 8
  store i32 0, ptr %3, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !9
  %9 = load i32, ptr %4, align 4, !tbaa !5
  %10 = icmp ne i32 %9, 2
  br i1 %10, label %11, label %14

11:                                               ; preds = %2
  %12 = load ptr, ptr @stderr, align 8, !tbaa !9
  %13 = call i32 (ptr, ptr, ...) @fprintf(ptr noundef %12, ptr noundef @.str) #6
  call void @exit(i32 noundef -1) #7
  unreachable

14:                                               ; preds = %2
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #6
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #6
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #6
  %15 = load ptr, ptr %5, align 8, !tbaa !9
  %16 = getelementptr inbounds ptr, ptr %15, i64 1
  %17 = load ptr, ptr %16, align 8, !tbaa !9
  %18 = call i32 @atoi(ptr noundef %17) #8
  %19 = call ptr @grayCode(i32 noundef %18, ptr noundef %7)
  store ptr %19, ptr %8, align 8, !tbaa !9
  store i32 0, ptr %6, align 4, !tbaa !5
  br label %20

20:                                               ; preds = %31, %14
  %21 = load i32, ptr %6, align 4, !tbaa !5
  %22 = load i32, ptr %7, align 4, !tbaa !5
  %23 = icmp slt i32 %21, %22
  br i1 %23, label %24, label %34

24:                                               ; preds = %20
  %25 = load ptr, ptr %8, align 8, !tbaa !9
  %26 = load i32, ptr %6, align 4, !tbaa !5
  %27 = sext i32 %26 to i64
  %28 = getelementptr inbounds i32, ptr %25, i64 %27
  %29 = load i32, ptr %28, align 4, !tbaa !5
  %30 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i32 noundef %29)
  br label %31

31:                                               ; preds = %24
  %32 = load i32, ptr %6, align 4, !tbaa !5
  %33 = add nsw i32 %32, 1
  store i32 %33, ptr %6, align 4, !tbaa !5
  br label %20, !llvm.loop !11

34:                                               ; preds = %20
  %35 = call i32 (ptr, ...) @printf(ptr noundef @.str.2)
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #6
  ret i32 0
}

; Function Attrs: nounwind
declare i32 @fprintf(ptr noundef, ptr noundef, ...) #2

; Function Attrs: noreturn nounwind
declare void @exit(i32 noundef) #3

; Function Attrs: inlinehint nounwind willreturn memory(read) uwtable
declare i32 @atoi(ptr noundef nonnull) #4

declare i32 @printf(ptr noundef, ...) #5

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 "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 = { noreturn 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 #4 = { inlinehint nounwind willreturn memory(read) 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 #5 = { "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 #6 = { nounwind }
attributes #7 = { noreturn nounwind }
attributes #8 = { nounwind willreturn memory(read) }

!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 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !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"

@stderr = external local_unnamed_addr global ptr, align 8
@.str = external hidden unnamed_addr constant [17 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local ptr @grayCode(i32 noundef, ptr noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nounwind uwtable
define dso_local noundef i32 @main(i32 noundef %0, ptr nocapture noundef readonly %1) local_unnamed_addr #0 {
  %3 = alloca i32, align 4
  %.not = icmp eq i32 %0, 2
  br i1 %.not, label %7, label %4

4:                                                ; preds = %2
  %5 = load ptr, ptr @stderr, align 8, !tbaa !5
  %6 = tail call i32 (ptr, ptr, ...) @fprintf(ptr noundef %5, ptr noundef nonnull @.str) #5
  tail call void @exit(i32 noundef -1) #6
  unreachable

7:                                                ; preds = %2
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #7
  %8 = getelementptr inbounds i8, ptr %1, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !5
  %10 = tail call i32 @atoi(ptr nocapture noundef %9) #8
  %11 = call ptr @grayCode(i32 noundef %10, ptr noundef nonnull %3)
  %12 = load i32, ptr %3, align 4, !tbaa !9
  %13 = icmp sgt i32 %12, 0
  br i1 %13, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %7, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %7 ]
  %14 = getelementptr inbounds i32, ptr %11, i64 %indvars.iv
  %15 = load i32, ptr %14, align 4, !tbaa !9
  %16 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %15)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %17 = load i32, ptr %3, align 4, !tbaa !9
  %18 = sext i32 %17 to i64
  %19 = icmp slt i64 %indvars.iv.next, %18
  br i1 %19, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge:                                      ; preds = %.lr.ph, %7
  %20 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #7
  ret i32 0
}

; Function Attrs: nofree nounwind
declare noundef i32 @fprintf(ptr nocapture noundef, ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: noreturn nounwind
declare void @exit(i32 noundef) local_unnamed_addr #3

; Function Attrs: inlinehint mustprogress nofree nounwind willreturn memory(read) uwtable
declare i32 @atoi(ptr nocapture noundef nonnull) local_unnamed_addr #4

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #3 = { noreturn 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 #4 = { inlinehint mustprogress nofree nounwind willreturn memory(read) 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 #5 = { cold nounwind }
attributes #6 = { noreturn nounwind }
attributes #7 = { nounwind }
attributes #8 = { nounwind willreturn memory(read) }

!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"}


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