; LLVM IR from zhemao/libds :: strutils (str_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"

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

4:                                                ; preds = %36, %1
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = load i32, ptr %3, align 4, !tbaa !9
  %7 = sext i32 %6 to i64
  %8 = getelementptr inbounds i8, ptr %5, i64 %7
  %9 = load i8, ptr %8, align 1, !tbaa !11
  %10 = icmp ne i8 %9, 0
  br i1 %10, label %11, label %39

11:                                               ; preds = %4
  %12 = call ptr @__ctype_b_loc() #4
  %13 = load ptr, ptr %12, align 8, !tbaa !5
  %14 = load ptr, ptr %2, align 8, !tbaa !5
  %15 = load i32, ptr %3, align 4, !tbaa !9
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds i8, ptr %14, i64 %16
  %18 = load i8, ptr %17, align 1, !tbaa !11
  %19 = sext i8 %18 to i32
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds i16, ptr %13, i64 %20
  %22 = load i16, ptr %21, align 2, !tbaa !12
  %23 = zext i16 %22 to i32
  %24 = and i32 %23, 256
  %25 = icmp ne i32 %24, 0
  br i1 %25, label %26, label %35

26:                                               ; preds = %11
  %27 = load ptr, ptr %2, align 8, !tbaa !5
  %28 = load i32, ptr %3, align 4, !tbaa !9
  %29 = sext i32 %28 to i64
  %30 = getelementptr inbounds i8, ptr %27, i64 %29
  %31 = load i8, ptr %30, align 1, !tbaa !11
  %32 = sext i8 %31 to i32
  %33 = add nsw i32 %32, 32
  %34 = trunc i32 %33 to i8
  store i8 %34, ptr %30, align 1, !tbaa !11
  br label %35

35:                                               ; preds = %26, %11
  br label %36

36:                                               ; preds = %35
  %37 = load i32, ptr %3, align 4, !tbaa !9
  %38 = add nsw i32 %37, 1
  store i32 %38, ptr %3, align 4, !tbaa !9
  br label %4, !llvm.loop !14

39:                                               ; preds = %4
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  ret void
}

; Function Attrs: nounwind willreturn memory(none)
declare ptr @__ctype_b_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 = !{!"int", !7, i64 0}
!11 = !{!7, !7, i64 0}
!12 = !{!13, !13, i64 0}
!13 = !{!"short", !7, i64 0}
!14 = distinct !{!14, !15}
!15 = !{!"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_lower(ptr nocapture noundef %0) local_unnamed_addr #0 {
  %2 = load i8, ptr %0, align 1, !tbaa !5
  %.not8 = icmp eq i8 %2, 0
  br i1 %.not8, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1
  %3 = tail call ptr @__ctype_b_loc() #2
  br label %4

4:                                                ; preds = %.lr.ph, %14
  %indvars.iv = phi i64 [ 0, %.lr.ph ], [ %indvars.iv.next, %14 ]
  %5 = phi i8 [ %2, %.lr.ph ], [ %16, %14 ]
  %6 = load ptr, ptr %3, align 8, !tbaa !8
  %7 = sext i8 %5 to i64
  %8 = getelementptr inbounds i16, ptr %6, i64 %7
  %9 = load i16, ptr %8, align 2, !tbaa !10
  %10 = and i16 %9, 256
  %.not7 = icmp eq i16 %10, 0
  br i1 %.not7, label %14, label %11

11:                                               ; preds = %4
  %12 = getelementptr inbounds i8, ptr %0, i64 %indvars.iv
  %13 = add i8 %5, 32
  store i8 %13, ptr %12, align 1, !tbaa !5
  br label %14

14:                                               ; preds = %4, %11
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %15 = getelementptr inbounds i8, ptr %0, i64 %indvars.iv.next
  %16 = load i8, ptr %15, align 1, !tbaa !5
  %.not = icmp eq i8 %16, 0
  br i1 %.not, label %._crit_edge, label %4, !llvm.loop !12

._crit_edge:                                      ; preds = %14, %1
  ret void
}

; Function Attrs: mustprogress nofree nosync nounwind willreturn memory(none)
declare ptr @__ctype_b_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, !6, i64 0}
!6 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"any pointer", !6, i64 0}
!10 = !{!11, !11, i64 0}
!11 = !{!"short", !6, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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