; LLVM IR from AlgoGenesis/C :: Backtracking Algorithms/Permutations and Combinations (Program)

; 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"

@.str = external hidden unnamed_addr constant [4 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @swap(ptr 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 void @permute(ptr noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %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
  store i32 %2, ptr %6, align 4, !tbaa !9
  %8 = load i32, ptr %5, align 4, !tbaa !9
  %9 = load i32, ptr %6, align 4, !tbaa !9
  %10 = icmp eq i32 %8, %9
  br i1 %10, label %11, label %14

11:                                               ; preds = %3
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = call i32 (ptr, ...) @printf(ptr noundef @.str, ptr noundef %12)
  br label %46

14:                                               ; preds = %3
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  %15 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %15, ptr %7, align 4, !tbaa !9
  br label %16

16:                                               ; preds = %42, %14
  %17 = load i32, ptr %7, align 4, !tbaa !9
  %18 = load i32, ptr %6, align 4, !tbaa !9
  %19 = icmp sle i32 %17, %18
  br i1 %19, label %21, label %20

20:                                               ; preds = %16
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  br label %45

21:                                               ; preds = %16
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = load i32, ptr %5, align 4, !tbaa !9
  %24 = sext i32 %23 to i64
  %25 = getelementptr inbounds i8, ptr %22, i64 %24
  %26 = load ptr, ptr %4, align 8, !tbaa !5
  %27 = load i32, ptr %7, align 4, !tbaa !9
  %28 = sext i32 %27 to i64
  %29 = getelementptr inbounds i8, ptr %26, i64 %28
  call void @swap(ptr noundef %25, ptr noundef %29)
  %30 = load ptr, ptr %4, align 8, !tbaa !5
  %31 = load i32, ptr %5, align 4, !tbaa !9
  %32 = add nsw i32 %31, 1
  %33 = load i32, ptr %6, align 4, !tbaa !9
  call void @permute(ptr noundef %30, i32 noundef %32, i32 noundef %33)
  %34 = load ptr, ptr %4, align 8, !tbaa !5
  %35 = load i32, ptr %5, align 4, !tbaa !9
  %36 = sext i32 %35 to i64
  %37 = getelementptr inbounds i8, ptr %34, i64 %36
  %38 = load ptr, ptr %4, align 8, !tbaa !5
  %39 = load i32, ptr %7, align 4, !tbaa !9
  %40 = sext i32 %39 to i64
  %41 = getelementptr inbounds i8, ptr %38, i64 %40
  call void @swap(ptr noundef %37, ptr noundef %41)
  br label %42

42:                                               ; preds = %21
  %43 = load i32, ptr %7, align 4, !tbaa !9
  %44 = add nsw i32 %43, 1
  store i32 %44, ptr %7, align 4, !tbaa !9
  br label %16, !llvm.loop !11

45:                                               ; preds = %20
  br label %46

46:                                               ; preds = %45, %11
  ret void
}

declare i32 @printf(ptr noundef, ...) #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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { "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 = { 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"

@.str = external hidden unnamed_addr constant [4 x i8], align 1

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

; Function Attrs: nounwind uwtable
define dso_local void @permute(ptr noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = icmp eq i32 %1, %2
  br i1 %4, label %9, label %.preheader

.preheader:                                       ; preds = %3
  %.not19 = icmp sgt i32 %1, %2
  br i1 %.not19, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %.preheader
  %5 = sext i32 %1 to i64
  %6 = getelementptr inbounds i8, ptr %0, i64 %5
  %7 = add nsw i32 %1, 1
  %8 = add i32 %2, 1
  br label %11

9:                                                ; preds = %3
  %10 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str, ptr noundef %0)
  br label %.loopexit

11:                                               ; preds = %.lr.ph, %11
  %indvars.iv = phi i64 [ %5, %.lr.ph ], [ %indvars.iv.next, %11 ]
  %12 = getelementptr inbounds i8, ptr %0, i64 %indvars.iv
  tail call void @swap(ptr noundef %6, ptr noundef %12)
  tail call void @permute(ptr noundef %0, i32 noundef %7, i32 noundef %2)
  tail call void @swap(ptr noundef %6, ptr noundef %12)
  %indvars.iv.next = add nsw i64 %indvars.iv, 1
  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
  %exitcond.not = icmp eq i32 %8, %lftr.wideiv
  br i1 %exitcond.not, label %.loopexit, label %11, !llvm.loop !5

.loopexit:                                        ; preds = %11, %.preheader, %9
  ret void
}

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #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" }
attributes #1 = { 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" }

!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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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