; LLVM IR from Ubpa/USTC_CG :: Homeworks/4_MinSurfMeshPara/project/src/Basic (StrAPI)

; 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 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) #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 nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32)) #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 uwtable
define dso_local void @_ZN4Ubpa6StrAPI12DelTailAfterERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEc(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull align 8 dereferenceable(32) %1, i8 noundef signext %2) #0 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i8, align 1
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  store ptr %0, ptr %4, align 8
  store ptr %1, ptr %5, align 8, !tbaa !5
  store i8 %2, ptr %6, align 1, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %9) #3
  %11 = trunc i64 %10 to i32
  %12 = sub nsw i32 %11, 1
  store i32 %12, ptr %7, align 4, !tbaa !10
  br label %13

13:                                               ; preds = %32, %3
  %14 = load i32, ptr %7, align 4, !tbaa !10
  %15 = icmp sge i32 %14, 0
  br i1 %15, label %17, label %16

16:                                               ; preds = %13
  store i32 2, ptr %8, align 4
  br label %35

17:                                               ; preds = %13
  %18 = load ptr, ptr %5, align 8, !tbaa !5
  %19 = load i32, ptr %7, align 4, !tbaa !10
  %20 = sext i32 %19 to i64
  %21 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %18, i64 noundef %20) #3
  %22 = load i8, ptr %21, align 1, !tbaa !9
  %23 = sext i8 %22 to i32
  %24 = load i8, ptr %6, align 1, !tbaa !9
  %25 = sext i8 %24 to i32
  %26 = icmp eq i32 %23, %25
  br i1 %26, label %27, label %31

27:                                               ; preds = %17
  %28 = load ptr, ptr %5, align 8, !tbaa !5
  %29 = load i32, ptr %7, align 4, !tbaa !10
  %30 = sext i32 %29 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) %28, i64 noundef 0, i64 noundef %30)
  store i32 1, ptr %8, align 4
  br label %35

31:                                               ; preds = %17
  br label %32

32:                                               ; preds = %31
  %33 = load i32, ptr %7, align 4, !tbaa !10
  %34 = add nsw i32 %33, -1
  store i32 %34, ptr %7, align 4, !tbaa !10
  br label %13, !llvm.loop !12

35:                                               ; preds = %27, %16
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  %36 = load i32, ptr %8, align 4
  switch i32 %36, label %40 [
    i32 2, label %37
    i32 1, label %39
  ]

37:                                               ; preds = %35
  %38 = load ptr, ptr %5, 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) %38)
  br label %39

39:                                               ; preds = %37, %35
  ret void

40:                                               ; preds = %35
  unreachable
}

; 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) #2 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 #0 align 2

attributes #0 = { 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 #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #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 = !{!7, !7, i64 0}
!10 = !{!11, !11, i64 0}
!11 = !{!"int", !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 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 #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress uwtable
define dso_local void @_ZN4Ubpa6StrAPI12DelTailAfterERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEc(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull align 8 dereferenceable(32) %1, i8 noundef signext %2) local_unnamed_addr #0 {
  %4 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #2
  %5 = and i64 %4, 4294967295
  br label %6

6:                                                ; preds = %9, %3
  %indvars.iv = phi i64 [ %10, %9 ], [ %5, %3 ]
  %7 = trunc nuw i64 %indvars.iv to i32
  %8 = icmp sgt i32 %7, 0
  br i1 %8, label %9, label %15

9:                                                ; preds = %6
  %10 = add nsw i64 %indvars.iv, -1
  %11 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %10) #2
  %12 = load i8, ptr %11, align 1, !tbaa !5
  %13 = icmp eq i8 %12, %2
  br i1 %13, label %14, label %6, !llvm.loop !8

14:                                               ; preds = %9
  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 0, i64 noundef %10)
  br label %16

15:                                               ; preds = %6
  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 %16

16:                                               ; preds = %14, %15
  ret void
}

; 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 #1 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 #0 align 2

attributes #0 = { 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 #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 }

!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,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass