; LLVM IR from UtkarshPathrabe/Competitive-Coding :: Model Algorithms/Backtracking/Graph Coloring.ll (Z6IsSafeii)

; 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"

@V = external dso_local global i32, align 4
@Graph = external dso_local global [100 x [100 x i32]], align 16
@Color = external dso_local global [100 x i32], align 16

; 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: mustprogress nounwind uwtable
define dso_local noundef zeroext i1 @_Z6IsSafeii(i32 noundef %0, i32 noundef %1) #1 {
  %3 = alloca i1, align 1
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  store i32 0, ptr %6, align 4, !tbaa !5
  br label %8

8:                                                ; preds = %31, %2
  %9 = load i32, ptr %6, align 4, !tbaa !5
  %10 = load i32, ptr @V, align 4, !tbaa !5
  %11 = icmp slt i32 %9, %10
  br i1 %11, label %13, label %12

12:                                               ; preds = %8
  store i32 2, ptr %7, align 4
  br label %34

13:                                               ; preds = %8
  %14 = load i32, ptr %4, align 4, !tbaa !5
  %15 = sext i32 %14 to i64
  %16 = getelementptr inbounds [100 x [100 x i32]], ptr @Graph, i64 0, i64 %15
  %17 = load i32, ptr %6, align 4, !tbaa !5
  %18 = sext i32 %17 to i64
  %19 = getelementptr inbounds [100 x i32], ptr %16, i64 0, i64 %18
  %20 = load i32, ptr %19, align 4, !tbaa !5
  %21 = icmp ne i32 %20, 0
  br i1 %21, label %22, label %30

22:                                               ; preds = %13
  %23 = load i32, ptr %5, align 4, !tbaa !5
  %24 = load i32, ptr %6, align 4, !tbaa !5
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds [100 x i32], ptr @Color, i64 0, i64 %25
  %27 = load i32, ptr %26, align 4, !tbaa !5
  %28 = icmp eq i32 %23, %27
  br i1 %28, label %29, label %30

29:                                               ; preds = %22
  store i1 false, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %34

30:                                               ; preds = %22, %13
  br label %31

31:                                               ; preds = %30
  %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 %8, !llvm.loop !9

34:                                               ; preds = %29, %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %35 = load i32, ptr %7, align 4
  switch i32 %35, label %39 [
    i32 2, label %36
    i32 1, label %37
  ]

36:                                               ; preds = %34
  store i1 true, ptr %3, align 1
  br label %37

37:                                               ; preds = %36, %34
  %38 = load i1, ptr %3, align 1
  ret i1 %38

39:                                               ; preds = %34
  unreachable
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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"}
!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"

@V = external dso_local local_unnamed_addr global i32, align 4
@Graph = external dso_local local_unnamed_addr global [100 x [100 x i32]], align 16
@Color = external dso_local local_unnamed_addr global [100 x i32], align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef zeroext i1 @_Z6IsSafeii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = load i32, ptr @V, align 4, !tbaa !5
  %4 = icmp slt i32 %3, 1
  br i1 %4, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2
  %5 = sext i32 %0 to i64
  %6 = zext nneg i32 %3 to i64
  %wide.trip.count = zext nneg i32 %3 to i64
  br label %7

7:                                                ; preds = %.lr.ph, %15
  %indvars.iv = phi i64 [ 0, %.lr.ph ], [ %indvars.iv.next, %15 ]
  %8 = phi i1 [ false, %.lr.ph ], [ %16, %15 ]
  %9 = getelementptr inbounds [100 x [100 x i32]], ptr @Graph, i64 0, i64 %5, i64 %indvars.iv
  %10 = load i32, ptr %9, align 4, !tbaa !5
  %.not = icmp eq i32 %10, 0
  br i1 %.not, label %15, label %11

11:                                               ; preds = %7
  %12 = getelementptr inbounds [100 x i32], ptr @Color, i64 0, i64 %indvars.iv
  %13 = load i32, ptr %12, align 4, !tbaa !5
  %14 = icmp eq i32 %13, %1
  br i1 %14, label %._crit_edge, label %15

15:                                               ; preds = %7, %11
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %16 = icmp uge i64 %indvars.iv.next, %6
  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond, label %._crit_edge, label %7, !llvm.loop !9

._crit_edge:                                      ; preds = %15, %11, %2
  %.lcssa = phi i1 [ true, %2 ], [ %8, %11 ], [ %16, %15 ]
  ret i1 %.lcssa
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(read, argmem: none, inaccessiblemem: 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 = !{!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: CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass