; LLVM IR from imteekay/algorithms :: computer_science/algorithms/recursion (reverse)

; 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 [3 x i8], align 1

; Function Attrs: nounwind uwtable
define dso_local i32 @reverse(ptr noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  %4 = load ptr, ptr %3, align 8, !tbaa !5
  %5 = call i64 @strlen(ptr noundef %4) #3
  %6 = icmp eq i64 %5, 0
  br i1 %6, label %7, label %8

7:                                                ; preds = %1
  store i32 0, ptr %2, align 4
  br label %24

8:                                                ; preds = %1
  %9 = load ptr, ptr %3, align 8, !tbaa !5
  %10 = load ptr, ptr %3, align 8, !tbaa !5
  %11 = call i64 @strlen(ptr noundef %10) #3
  %12 = sub i64 %11, 1
  %13 = getelementptr inbounds i8, ptr %9, i64 %12
  %14 = load i8, ptr %13, align 1, !tbaa !9
  %15 = sext i8 %14 to i32
  %16 = call i32 (ptr, ...) @printf(ptr noundef @.str, i32 noundef %15)
  %17 = load ptr, ptr %3, align 8, !tbaa !5
  %18 = load ptr, ptr %3, align 8, !tbaa !5
  %19 = call i64 @strlen(ptr noundef %18) #3
  %20 = sub i64 %19, 1
  %21 = getelementptr inbounds i8, ptr %17, i64 %20
  store i8 0, ptr %21, align 1, !tbaa !9
  %22 = load ptr, ptr %3, align 8, !tbaa !5
  %23 = call i32 @reverse(ptr noundef %22)
  store i32 %23, ptr %2, align 4
  br label %24

24:                                               ; preds = %8, %7
  %25 = load i32, ptr %2, align 4
  ret i32 %25
}

; Function Attrs: nounwind willreturn memory(read)
declare i64 @strlen(ptr noundef) #1

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 = { nounwind willreturn memory(read) "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 = { "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 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 = !{!7, !7, i64 0}


; 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 [3 x i8], align 1

; Function Attrs: nofree nounwind uwtable
define dso_local noundef i32 @reverse(ptr nocapture noundef %0) local_unnamed_addr #0 {
  %invariant.gep = getelementptr i8, ptr %0, i64 -1
  %2 = tail call i64 @strlen(ptr noundef nonnull dereferenceable(1) %0) #3
  %.not = icmp eq i64 %2, 0
  br i1 %.not, label %tailrecurse._crit_edge, label %tailrecurse

tailrecurse:                                      ; preds = %1, %tailrecurse
  %3 = phi i64 [ %8, %tailrecurse ], [ %2, %1 ]
  %gep = getelementptr i8, ptr %invariant.gep, i64 %3
  %4 = load i8, ptr %gep, align 1, !tbaa !5
  %5 = sext i8 %4 to i32
  %6 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str, i32 noundef %5)
  %7 = tail call i64 @strlen(ptr noundef nonnull dereferenceable(1) %0) #3
  %gep9 = getelementptr i8, ptr %invariant.gep, i64 %7
  store i8 0, ptr %gep9, align 1, !tbaa !5
  %8 = tail call i64 @strlen(ptr noundef nonnull dereferenceable(1) %0) #3
  %9 = icmp eq i64 %8, 0
  br i1 %9, label %tailrecurse._crit_edge, label %tailrecurse

tailrecurse._crit_edge:                           ; preds = %tailrecurse, %1
  ret i32 0
}

; Function Attrs: mustprogress nofree nounwind willreturn memory(argmem: read)
declare i64 @strlen(ptr nocapture noundef) local_unnamed_addr #1

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

attributes #0 = { nofree 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 nofree nounwind willreturn memory(argmem: read) "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 = { 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 = { 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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}


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