; LLVM IR from steps3d/graphics-book :: Code/Core (stringUtils)

; 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"

%"class.std::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32)) #0 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress uwtable
declare void @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6substrEmm(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8, ptr noundef nonnull align 8 dereferenceable(32), i64 noundef, i64 noundef) #2 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) #0 align 2

; Function Attrs: mustprogress uwtable
declare void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2ERKS4_(ptr noundef nonnull align 8 dereferenceable(32), ptr noundef nonnull align 8 dereferenceable(32)) unnamed_addr #2 align 2

; Function Attrs: mustprogress uwtable
define dso_local void @_Z11getFileNameRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull align 8 dereferenceable(32) %1) #2 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i8, align 1
  store ptr %0, ptr %3, align 8
  store ptr %1, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  %9 = load ptr, ptr %4, align 8, !tbaa !5
  %10 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %9) #3
  %11 = trunc i64 %10 to i32
  store i32 %11, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  %12 = load i32, ptr %5, align 4, !tbaa !9
  %13 = sub nsw i32 %12, 1
  store i32 %13, ptr %6, align 4, !tbaa !9
  br label %14

14:                                               ; preds = %44, %2
  %15 = load i32, ptr %6, align 4, !tbaa !9
  %16 = icmp sge i32 %15, 0
  br i1 %16, label %18, label %17

17:                                               ; preds = %14
  store i32 2, ptr %7, align 4
  br label %47

18:                                               ; preds = %14
  call void @llvm.lifetime.start.p0(i64 1, ptr %8) #3
  %19 = load ptr, ptr %4, align 8, !tbaa !5
  %20 = load i32, ptr %6, align 4, !tbaa !9
  %21 = sext i32 %20 to i64
  %22 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %19, i64 noundef %21) #3
  %23 = load i8, ptr %22, align 1, !tbaa !11
  store i8 %23, ptr %8, align 1, !tbaa !11
  %24 = load i8, ptr %8, align 1, !tbaa !11
  %25 = sext i8 %24 to i32
  %26 = icmp eq i32 %25, 92
  br i1 %26, label %35, label %27

27:                                               ; preds = %18
  %28 = load i8, ptr %8, align 1, !tbaa !11
  %29 = sext i8 %28 to i32
  %30 = icmp eq i32 %29, 47
  br i1 %30, label %35, label %31

31:                                               ; preds = %27
  %32 = load i8, ptr %8, align 1, !tbaa !11
  %33 = sext i8 %32 to i32
  %34 = icmp eq i32 %33, 58
  br i1 %34, label %35, label %40

35:                                               ; preds = %31, %27, %18
  %36 = load ptr, ptr %4, align 8, !tbaa !5
  %37 = load i32, ptr %6, align 4, !tbaa !9
  %38 = add nsw i32 %37, 1
  %39 = sext i32 %38 to i64
  call void @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6substrEmm(ptr dead_on_unwind writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull align 8 dereferenceable(32) %36, i64 noundef %39, i64 noundef -1)
  store i32 1, ptr %7, align 4
  br label %41

40:                                               ; preds = %31
  store i32 0, ptr %7, align 4
  br label %41

41:                                               ; preds = %40, %35
  call void @llvm.lifetime.end.p0(i64 1, ptr %8) #3
  %42 = load i32, ptr %7, align 4
  switch i32 %42, label %47 [
    i32 0, label %43
  ]

43:                                               ; preds = %41
  br label %44

44:                                               ; preds = %43
  %45 = load i32, ptr %6, align 4, !tbaa !9
  %46 = add nsw i32 %45, -1
  store i32 %46, ptr %6, align 4, !tbaa !9
  br label %14, !llvm.loop !12

47:                                               ; preds = %41, %17
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  %48 = load i32, ptr %7, align 4
  switch i32 %48, label %51 [
    i32 2, label %49
  ]

49:                                               ; preds = %47
  %50 = load ptr, ptr %4, align 8, !tbaa !5
  call void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2ERKS4_(ptr noundef nonnull align 8 dereferenceable(32) %0, ptr noundef nonnull align 8 dereferenceable(32) %50)
  store i32 1, ptr %7, align 4
  br label %51

51:                                               ; preds = %49, %47
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  ret void
}

attributes #0 = { 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 #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { mustprogress 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 #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++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!7, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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"

%"class.std::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress uwtable
declare void @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6substrEmm(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8, ptr noundef nonnull align 8 dereferenceable(32), i64 noundef, i64 noundef) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress uwtable
declare void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2ERKS4_(ptr noundef nonnull align 8 dereferenceable(32), ptr noundef nonnull align 8 dereferenceable(32)) unnamed_addr #1 align 2

; Function Attrs: mustprogress uwtable
define dso_local void @_Z11getFileNameRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull align 8 dereferenceable(32) %1) local_unnamed_addr #1 {
  %3 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #2
  %4 = trunc i64 %3 to i32
  %5 = icmp slt i32 %4, 1
  br i1 %5, label %.critedge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %2
  %6 = and i64 %3, 2147483647
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.backedge
  %indvars.iv = phi i64 [ %6, %.lr.ph.preheader ], [ %indvars.iv.next, %.backedge ]
  %indvars.iv.next = add nsw i64 %indvars.iv, -1
  %7 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %indvars.iv.next) #2
  %8 = load i8, ptr %7, align 1, !tbaa !5
  switch i8 %8, label %.backedge [
    i8 92, label %9
    i8 58, label %9
    i8 47, label %9
  ]

9:                                                ; preds = %.lr.ph, %.lr.ph, %.lr.ph
  tail call void @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6substrEmm(ptr dead_on_unwind writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %indvars.iv, i64 noundef -1)
  switch i8 %8, label %.backedge [
    i8 92, label %.loopexit
    i8 58, label %.loopexit
    i8 47, label %.loopexit
  ]

.backedge:                                        ; preds = %9, %.lr.ph
  %10 = icmp ult i64 %indvars.iv, 2
  br i1 %10, label %.critedge, label %.lr.ph, !llvm.loop !8

.critedge:                                        ; preds = %.backedge, %2
  tail call void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2ERKS4_(ptr noundef nonnull align 8 dereferenceable(32) %0, ptr noundef nonnull align 8 dereferenceable(32) %1)
  br label %.loopexit

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

attributes #0 = { 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 #1 = { mustprogress 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 }

!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: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass