; LLVM IR from wrnlb666/yet-another-string-library-in-c :: yasli (str_to_lower)

; 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"

%struct.string_t = type { i64, i64, [1 x i8] }

; 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: nounwind uwtable
define dso_local void @str_to_lower(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i64, align 8
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  store i64 0, ptr %3, align 8, !tbaa !9
  br label %6

6:                                                ; preds = %32, %1
  %7 = load i64, ptr %3, align 8, !tbaa !9
  %8 = load ptr, ptr %2, align 8, !tbaa !5
  %9 = getelementptr inbounds %struct.string_t, ptr %8, i32 0, i32 0
  %10 = load i64, ptr %9, align 8, !tbaa !11
  %11 = icmp ult i64 %7, %10
  br i1 %11, label %13, label %12

12:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  br label %35

13:                                               ; preds = %6
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  %14 = call ptr @__ctype_tolower_loc() #4
  %15 = load ptr, ptr %14, align 8, !tbaa !5
  %16 = load ptr, ptr %2, align 8, !tbaa !5
  %17 = getelementptr inbounds %struct.string_t, ptr %16, i32 0, i32 2
  %18 = load i64, ptr %3, align 8, !tbaa !9
  %19 = getelementptr inbounds [1 x i8], ptr %17, i64 0, i64 %18
  %20 = load i8, ptr %19, align 1, !tbaa !13
  %21 = sext i8 %20 to i32
  %22 = sext i32 %21 to i64
  %23 = getelementptr inbounds i32, ptr %15, i64 %22
  %24 = load i32, ptr %23, align 4, !tbaa !14
  store i32 %24, ptr %4, align 4, !tbaa !14
  %25 = load i32, ptr %4, align 4, !tbaa !14
  store i32 %25, ptr %5, align 4, !tbaa !14
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  %26 = load i32, ptr %5, align 4, !tbaa !14
  %27 = trunc i32 %26 to i8
  %28 = load ptr, ptr %2, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.string_t, ptr %28, i32 0, i32 2
  %30 = load i64, ptr %3, align 8, !tbaa !9
  %31 = getelementptr inbounds [1 x i8], ptr %29, i64 0, i64 %30
  store i8 %27, ptr %31, align 1, !tbaa !13
  br label %32

32:                                               ; preds = %13
  %33 = load i64, ptr %3, align 8, !tbaa !9
  %34 = add i64 %33, 1
  store i64 %34, ptr %3, align 8, !tbaa !9
  br label %6, !llvm.loop !16

35:                                               ; preds = %12
  ret void
}

; Function Attrs: nounwind willreturn memory(none)
declare ptr @__ctype_tolower_loc() #2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 willreturn memory(none) "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 }
attributes #4 = { nounwind willreturn memory(none) }

!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 = !{!"long", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"string_t", !10, i64 0, !10, i64 8, !7, i64 16}
!13 = !{!7, !7, i64 0}
!14 = !{!15, !15, i64 0}
!15 = !{!"int", !7, i64 0}
!16 = distinct !{!16, !17}
!17 = !{!"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"

; Function Attrs: nofree nosync nounwind memory(read, argmem: readwrite, inaccessiblemem: none) uwtable
define dso_local void @str_to_lower(ptr nocapture noundef %0) local_unnamed_addr #0 {
  %2 = load i64, ptr %0, align 8, !tbaa !5
  %.not = icmp eq i64 %2, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1
  %3 = tail call ptr @__ctype_tolower_loc() #2
  %4 = getelementptr inbounds i8, ptr %0, i64 16
  br label %5

._crit_edge:                                      ; preds = %5, %1
  ret void

5:                                                ; preds = %.lr.ph, %5
  %.08 = phi i64 [ 0, %.lr.ph ], [ %13, %5 ]
  %6 = load ptr, ptr %3, align 8, !tbaa !10
  %7 = getelementptr inbounds [1 x i8], ptr %4, i64 0, i64 %.08
  %8 = load i8, ptr %7, align 1, !tbaa !12
  %9 = sext i8 %8 to i64
  %10 = getelementptr inbounds i32, ptr %6, i64 %9
  %11 = load i32, ptr %10, align 4, !tbaa !13
  %12 = trunc i32 %11 to i8
  store i8 %12, ptr %7, align 1, !tbaa !12
  %13 = add nuw i64 %.08, 1
  %14 = load i64, ptr %0, align 8, !tbaa !5
  %15 = icmp ult i64 %13, %14
  br i1 %15, label %5, label %._crit_edge, !llvm.loop !15
}

; Function Attrs: mustprogress nofree nosync nounwind willreturn memory(none)
declare ptr @__ctype_tolower_loc() local_unnamed_addr #1

attributes #0 = { nofree nosync nounwind memory(read, argmem: readwrite, 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" }
attributes #1 = { mustprogress nofree nosync nounwind willreturn memory(none) "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 willreturn memory(none) }

!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, !7, i64 0}
!6 = !{!"string_t", !7, i64 0, !7, i64 8, !8, i64 16}
!7 = !{!"long", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!11, !11, i64 0}
!11 = !{!"any pointer", !8, i64 0}
!12 = !{!8, !8, i64 0}
!13 = !{!14, !14, i64 0}
!14 = !{!"int", !8, i64 0}
!15 = distinct !{!15, !16}
!16 = !{!"llvm.loop.mustprogress"}


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