; LLVM IR from JessonYue/LeetCodeLearning :: Array/wuchao/other/7-16 c实现string函数 (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"

; Function Attrs: nounwind uwtable
define dso_local ptr @strcpy(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = call i64 @stringLen(ptr noundef %5)
  %7 = mul i64 %6, 1
  %8 = call noalias ptr @malloc(i64 noundef %7) #4
  store ptr %8, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  store i32 0, ptr %4, align 4, !tbaa !9
  br label %9

9:                                                ; preds = %17, %1
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = load i32, ptr %4, align 4, !tbaa !9
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds i8, ptr %10, i64 %12
  %14 = load i8, ptr %13, align 1, !tbaa !11
  %15 = sext i8 %14 to i32
  %16 = icmp ne i32 %15, 0
  br i1 %16, label %17, label %29

17:                                               ; preds = %9
  %18 = load ptr, ptr %2, align 8, !tbaa !5
  %19 = load i32, ptr %4, align 4, !tbaa !9
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds i8, ptr %18, i64 %20
  %22 = load i8, ptr %21, align 1, !tbaa !11
  %23 = load ptr, ptr %3, align 8, !tbaa !5
  %24 = load i32, ptr %4, align 4, !tbaa !9
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds i8, ptr %23, i64 %25
  store i8 %22, ptr %26, align 1, !tbaa !11
  %27 = load i32, ptr %4, align 4, !tbaa !9
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %4, align 4, !tbaa !9
  br label %9, !llvm.loop !12

29:                                               ; preds = %9
  %30 = load ptr, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  ret ptr %30
}

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

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #2

; Function Attrs: nounwind uwtable
declare dso_local i64 @stringLen(ptr noundef) #0

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

attributes #0 = { 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 = { nounwind allocsize(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 }
attributes #4 = { nounwind allocsize(0) }

!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 = 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"

; Function Attrs: nounwind uwtable
define dso_local noalias noundef ptr @strcpy(ptr noundef %0) local_unnamed_addr #0 {
  %2 = tail call i64 @stringLen(ptr noundef %0)
  %3 = tail call noalias ptr @malloc(i64 noundef %2) #2
  %4 = load i8, ptr %0, align 1, !tbaa !5
  %.not8 = icmp eq i8 %4, 0
  br i1 %.not8, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %1 ]
  %5 = phi i8 [ %8, %.lr.ph ], [ %4, %1 ]
  %6 = getelementptr inbounds i8, ptr %3, i64 %indvars.iv
  store i8 %5, ptr %6, align 1, !tbaa !5
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %7 = getelementptr inbounds i8, ptr %0, i64 %indvars.iv.next
  %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 %3
}

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #1

; Function Attrs: nounwind uwtable
declare dso_local i64 @stringLen(ptr noundef) local_unnamed_addr #0

attributes #0 = { 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 nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "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 allocsize(0) }

!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 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


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