; LLVM IR from yinqiwen/ardb :: src/common/util/string_helper.ll (ZN4ardb11str_tolowerEPc)

; 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"

; 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 ptr @_ZN4ardb11str_tolowerEPc(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  %4 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %4, ptr %3, align 8, !tbaa !5
  br label %5

5:                                                ; preds = %9, %1
  %6 = load ptr, ptr %3, align 8, !tbaa !5
  %7 = load i8, ptr %6, align 1, !tbaa !9
  %8 = icmp ne i8 %7, 0
  br i1 %8, label %9, label %18

9:                                                ; preds = %5
  %10 = load ptr, ptr %3, align 8, !tbaa !5
  %11 = load i8, ptr %10, align 1, !tbaa !9
  %12 = sext i8 %11 to i32
  %13 = call i32 @tolower(i32 noundef %12) #4
  %14 = trunc i32 %13 to i8
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  store i8 %14, ptr %15, align 1, !tbaa !9
  %16 = load ptr, ptr %3, align 8, !tbaa !5
  %17 = getelementptr inbounds i8, ptr %16, i32 1
  store ptr %17, ptr %3, align 8, !tbaa !5
  br label %5, !llvm.loop !10

18:                                               ; preds = %5
  %19 = load ptr, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  ret ptr %19
}

; Function Attrs: nounwind willreturn memory(read)
declare i32 @tolower(i32 noundef) #2

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 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 #3 = { nounwind }
attributes #4 = { 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++ TBAA"}
!9 = !{!7, !7, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"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: mustprogress nofree nounwind memory(readwrite, inaccessiblemem: read) uwtable
define dso_local noundef ptr @_ZN4ardb11str_tolowerEPc(ptr noundef returned %0) local_unnamed_addr #0 {
  %2 = load i8, ptr %0, align 1, !tbaa !5
  %.not7 = icmp eq i8 %2, 0
  br i1 %.not7, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1, %.lr.ph
  %3 = phi i8 [ %8, %.lr.ph ], [ %2, %1 ]
  %.08 = phi ptr [ %7, %.lr.ph ], [ %0, %1 ]
  %4 = sext i8 %3 to i32
  %5 = tail call i32 @tolower(i32 noundef %4) #2
  %6 = trunc i32 %5 to i8
  store i8 %6, ptr %.08, align 1, !tbaa !5
  %7 = getelementptr inbounds i8, ptr %.08, i64 1
  %8 = load i8, ptr %7, align 1, !tbaa !5
  %.not = icmp eq i8 %8, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8

._crit_edge:                                      ; preds = %.lr.ph, %1
  ret ptr %0
}

; Function Attrs: mustprogress nofree nounwind willreturn memory(read)
declare i32 @tolower(i32 noundef) local_unnamed_addr #1

attributes #0 = { mustprogress nofree nounwind memory(readwrite, inaccessiblemem: 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 #1 = { mustprogress nofree 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 = { 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++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


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