; LLVM IR from UtkarshPathrabe/Competitive-Coding :: Model Algorithms/Pattern Searching (KMP Pattern Searching)

; 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: mustprogress uwtable
define dso_local void @_Z10computeLPSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEPi(ptr noundef %0, ptr noundef %1) #0 {
  %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
  store ptr %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  store i32 0, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  store i32 1, ptr %6, align 4, !tbaa !9
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  %9 = getelementptr inbounds i32, ptr %8, i64 0
  store i32 0, ptr %9, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  %10 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %11 = trunc i64 %10 to i32
  store i32 %11, ptr %7, align 4, !tbaa !9
  br label %12

12:                                               ; preds = %53, %2
  %13 = load i32, ptr %6, align 4, !tbaa !9
  %14 = load i32, ptr %7, align 4, !tbaa !9
  %15 = icmp slt i32 %13, %14
  br i1 %15, label %16, label %54

16:                                               ; preds = %12
  %17 = load i32, ptr %6, align 4, !tbaa !9
  %18 = sext i32 %17 to i64
  %19 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %18)
  %20 = load i8, ptr %19, align 1, !tbaa !11
  %21 = sext i8 %20 to i32
  %22 = load i32, ptr %5, align 4, !tbaa !9
  %23 = sext i32 %22 to i64
  %24 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %23)
  %25 = load i8, ptr %24, align 1, !tbaa !11
  %26 = sext i8 %25 to i32
  %27 = icmp eq i32 %21, %26
  br i1 %27, label %28, label %36

28:                                               ; preds = %16
  %29 = load i32, ptr %5, align 4, !tbaa !9
  %30 = add nsw i32 %29, 1
  store i32 %30, ptr %5, align 4, !tbaa !9
  %31 = load ptr, ptr %4, align 8, !tbaa !5
  %32 = load i32, ptr %6, align 4, !tbaa !9
  %33 = add nsw i32 %32, 1
  store i32 %33, ptr %6, align 4, !tbaa !9
  %34 = sext i32 %32 to i64
  %35 = getelementptr inbounds i32, ptr %31, i64 %34
  store i32 %30, ptr %35, align 4, !tbaa !9
  br label %53

36:                                               ; preds = %16
  %37 = load i32, ptr %5, align 4, !tbaa !9
  %38 = icmp ne i32 %37, 0
  br i1 %38, label %39, label %46

39:                                               ; preds = %36
  %40 = load ptr, ptr %4, align 8, !tbaa !5
  %41 = load i32, ptr %5, align 4, !tbaa !9
  %42 = sub nsw i32 %41, 1
  %43 = sext i32 %42 to i64
  %44 = getelementptr inbounds i32, ptr %40, i64 %43
  %45 = load i32, ptr %44, align 4, !tbaa !9
  store i32 %45, ptr %5, align 4, !tbaa !9
  br label %52

46:                                               ; preds = %36
  %47 = load ptr, ptr %4, align 8, !tbaa !5
  %48 = load i32, ptr %6, align 4, !tbaa !9
  %49 = add nsw i32 %48, 1
  store i32 %49, ptr %6, align 4, !tbaa !9
  %50 = sext i32 %48 to i64
  %51 = getelementptr inbounds i32, ptr %47, i64 %50
  store i32 0, ptr %51, align 4, !tbaa !9
  br label %52

52:                                               ; preds = %46, %39
  br label %53

53:                                               ; preds = %52, %28
  br label %12, !llvm.loop !12

54:                                               ; preds = %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  ret void
}

; 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_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32)) #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), 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

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 = !{!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: mustprogress nounwind uwtable
define dso_local void @_Z10computeLPSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEPi(ptr noundef nonnull %0, ptr nocapture noundef %1) local_unnamed_addr #0 {
  store i32 0, ptr %1, align 4, !tbaa !5
  %3 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %4 = trunc i64 %3 to i32
  %invariant.gep = getelementptr i8, ptr %1, i64 -4
  %5 = icmp sgt i32 %4, 1
  br i1 %5, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %2, %23
  %.015 = phi i32 [ %.1, %23 ], [ 0, %2 ]
  %.01214 = phi i32 [ %.113, %23 ], [ 1, %2 ]
  %6 = sext i32 %.01214 to i64
  %7 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %6)
  %8 = load i8, ptr %7, align 1, !tbaa !9
  %9 = sext i32 %.015 to i64
  %10 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %9)
  %11 = load i8, ptr %10, align 1, !tbaa !9
  %12 = icmp eq i8 %8, %11
  br i1 %12, label %13, label %17

13:                                               ; preds = %.lr.ph
  %14 = add nsw i32 %.015, 1
  %15 = add nsw i32 %.01214, 1
  %16 = getelementptr inbounds i32, ptr %1, i64 %6
  store i32 %14, ptr %16, align 4, !tbaa !5
  br label %23

17:                                               ; preds = %.lr.ph
  %.not = icmp eq i32 %.015, 0
  br i1 %.not, label %20, label %18

18:                                               ; preds = %17
  %gep = getelementptr i32, ptr %invariant.gep, i64 %9
  %19 = load i32, ptr %gep, align 4, !tbaa !5
  br label %23

20:                                               ; preds = %17
  %21 = add nsw i32 %.01214, 1
  %22 = getelementptr inbounds i32, ptr %1, i64 %6
  store i32 0, ptr %22, align 4, !tbaa !5
  br label %23

23:                                               ; preds = %18, %20, %13
  %.113 = phi i32 [ %15, %13 ], [ %.01214, %18 ], [ %21, %20 ]
  %.1 = phi i32 [ %14, %13 ], [ %19, %18 ], [ 0, %20 ]
  %24 = icmp slt i32 %.113, %4
  br i1 %24, label %.lr.ph, label %._crit_edge, !llvm.loop !10

._crit_edge:                                      ; preds = %23, %2
  ret void
}

; 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 nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) local_unnamed_addr #0 align 2

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 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!7, !7, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"llvm.loop.mustprogress"}


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