; LLVM IR from JessonYue/LeetCodeLearning :: Array/zhangjunwei/7.13-7.18 (str)

; 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 i32 @my_memcmp(ptr noundef %0, ptr noundef %1, i64 noundef %2) #1 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i64, align 8
  %7 = alloca ptr, align 8
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  store i64 %2, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #2
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #2
  store i32 0, ptr %9, align 4, !tbaa !11
  %10 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %10, ptr %7, align 8, !tbaa !5
  %11 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %11, ptr %8, align 8, !tbaa !5
  br label %12

12:                                               ; preds = %26, %3
  %13 = load i64, ptr %6, align 8, !tbaa !9
  %14 = icmp ult i64 0, %13
  br i1 %14, label %15, label %33

15:                                               ; preds = %12
  %16 = load ptr, ptr %7, align 8, !tbaa !5
  %17 = load i8, ptr %16, align 1, !tbaa !13
  %18 = zext i8 %17 to i32
  %19 = load ptr, ptr %8, align 8, !tbaa !5
  %20 = load i8, ptr %19, align 1, !tbaa !13
  %21 = zext i8 %20 to i32
  %22 = sub nsw i32 %18, %21
  store i32 %22, ptr %9, align 4, !tbaa !11
  %23 = icmp ne i32 %22, 0
  br i1 %23, label %24, label %25

24:                                               ; preds = %15
  br label %33

25:                                               ; preds = %15
  br label %26

26:                                               ; preds = %25
  %27 = load ptr, ptr %7, align 8, !tbaa !5
  %28 = getelementptr inbounds i8, ptr %27, i32 1
  store ptr %28, ptr %7, align 8, !tbaa !5
  %29 = load ptr, ptr %8, align 8, !tbaa !5
  %30 = getelementptr inbounds i8, ptr %29, i32 1
  store ptr %30, ptr %8, align 8, !tbaa !5
  %31 = load i64, ptr %6, align 8, !tbaa !9
  %32 = add i64 %31, -1
  store i64 %32, ptr %6, align 8, !tbaa !9
  br label %12, !llvm.loop !14

33:                                               ; preds = %24, %12
  %34 = load i32, ptr %9, align 4, !tbaa !11
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #2
  ret i32 %34
}

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 }

!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 = !{!"long", !7, i64 0}
!11 = !{!12, !12, i64 0}
!12 = !{!"int", !7, i64 0}
!13 = !{!7, !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 norecurse nosync nounwind memory(read, inaccessiblemem: none) uwtable
define dso_local range(i32 -255, 256) i32 @my_memcmp(ptr nocapture noundef readonly %0, ptr nocapture noundef readonly %1, i64 noundef %2) local_unnamed_addr #0 {
  %.not14 = icmp eq i64 %2, 0
  br i1 %.not14, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %3, %9
  %.0817 = phi ptr [ %11, %9 ], [ %1, %3 ]
  %.0916 = phi ptr [ %10, %9 ], [ %0, %3 ]
  %.01015 = phi i64 [ %12, %9 ], [ %2, %3 ]
  %4 = load i8, ptr %.0916, align 1, !tbaa !5
  %5 = zext i8 %4 to i32
  %6 = load i8, ptr %.0817, align 1, !tbaa !5
  %7 = zext i8 %6 to i32
  %8 = sub nsw i32 %5, %7
  %.not13 = icmp eq i32 %8, 0
  br i1 %.not13, label %9, label %._crit_edge

9:                                                ; preds = %.lr.ph
  %10 = getelementptr inbounds i8, ptr %.0916, i64 1
  %11 = getelementptr inbounds i8, ptr %.0817, i64 1
  %12 = add i64 %.01015, -1
  %.not = icmp eq i64 %12, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8

._crit_edge:                                      ; preds = %9, %.lr.ph, %3
  %.1 = phi i32 [ 0, %3 ], [ %8, %.lr.ph ], [ 0, %9 ]
  ret i32 %.1
}

attributes #0 = { nofree norecurse nosync nounwind memory(read, 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" }

!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: GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass