; LLVM IR from pacifiquem/awesome-algorithms :: src/String Matching (Brute-Force-String-Matching)

; 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::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }

@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [16 x i8], align 1

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z9findFirstNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES4_(ptr noundef %0, ptr noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #4
  %11 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #4
  %12 = trunc i64 %11 to i32
  store i32 %12, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #4
  %13 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #4
  %14 = trunc i64 %13 to i32
  store i32 %14, ptr %7, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #4
  store i32 0, ptr %8, align 4, !tbaa !9
  br label %15

15:                                               ; preds = %56, %2
  %16 = load i32, ptr %8, align 4, !tbaa !9
  %17 = load i32, ptr %7, align 4, !tbaa !9
  %18 = load i32, ptr %6, align 4, !tbaa !9
  %19 = sub nsw i32 %17, %18
  %20 = icmp slt i32 %16, %19
  br i1 %20, label %22, label %21

21:                                               ; preds = %15
  store i32 2, ptr %9, align 4
  br label %59

22:                                               ; preds = %15
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #4
  store i32 0, ptr %10, align 4, !tbaa !9
  br label %23

23:                                               ; preds = %43, %22
  %24 = load i32, ptr %10, align 4, !tbaa !9
  %25 = load i32, ptr %6, align 4, !tbaa !9
  %26 = icmp slt i32 %24, %25
  br i1 %26, label %27, label %41

27:                                               ; preds = %23
  %28 = load i32, ptr %8, align 4, !tbaa !9
  %29 = load i32, ptr %10, align 4, !tbaa !9
  %30 = add nsw i32 %28, %29
  %31 = sext i32 %30 to i64
  %32 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %31)
  %33 = load i8, ptr %32, align 1, !tbaa !11
  %34 = sext i8 %33 to i32
  %35 = load i32, ptr %10, align 4, !tbaa !9
  %36 = sext i32 %35 to i64
  %37 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %36)
  %38 = load i8, ptr %37, align 1, !tbaa !11
  %39 = sext i8 %38 to i32
  %40 = icmp eq i32 %34, %39
  br label %41

41:                                               ; preds = %27, %23
  %42 = phi i1 [ false, %23 ], [ %40, %27 ]
  br i1 %42, label %43, label %46

43:                                               ; preds = %41
  %44 = load i32, ptr %10, align 4, !tbaa !9
  %45 = add nsw i32 %44, 1
  store i32 %45, ptr %10, align 4, !tbaa !9
  br label %23, !llvm.loop !12

46:                                               ; preds = %41
  %47 = load i32, ptr %10, align 4, !tbaa !9
  %48 = load i32, ptr %6, align 4, !tbaa !9
  %49 = icmp eq i32 %47, %48
  br i1 %49, label %50, label %52

50:                                               ; preds = %46
  %51 = load i32, ptr %8, align 4, !tbaa !9
  store i32 %51, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %53

52:                                               ; preds = %46
  store i32 0, ptr %9, align 4
  br label %53

53:                                               ; preds = %52, %50
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #4
  %54 = load i32, ptr %9, align 4
  switch i32 %54, label %59 [
    i32 0, label %55
  ]

55:                                               ; preds = %53
  br label %56

56:                                               ; preds = %55
  %57 = load i32, ptr %8, align 4, !tbaa !9
  %58 = add nsw i32 %57, 1
  store i32 %58, ptr %8, align 4, !tbaa !9
  br label %15, !llvm.loop !14

59:                                               ; preds = %53, %21
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #4
  %60 = load i32, ptr %9, align 4
  switch i32 %60, label %64 [
    i32 2, label %61
  ]

61:                                               ; preds = %59
  %62 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str)
  %63 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %62, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  store i32 -1, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %64

64:                                               ; preds = %61, %59
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #4
  %65 = load i32, ptr %3, align 4
  ret i32 %65
}

; 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

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #3

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #0 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #3

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 = { inlinehint 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 #4 = { 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"}
!14 = distinct !{!14, !13}


; 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::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }

@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [16 x i8], align 1

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z9findFirstNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES4_(ptr noundef nonnull %0, ptr noundef %1) local_unnamed_addr #0 {
  %3 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %4 = trunc i64 %3 to i32
  %5 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #3
  %6 = trunc i64 %5 to i32
  %7 = sub nsw i32 %6, %4
  %.not2127 = icmp sgt i32 %7, 0
  br i1 %.not2127, label %.preheader.lr.ph, label %.thread

.preheader.lr.ph:                                 ; preds = %2
  %8 = icmp sgt i32 %4, 0
  br i1 %8, label %.preheader.us.preheader, label %.preheader.lr.ph.split

.preheader.us.preheader:                          ; preds = %.preheader.lr.ph
  %wide.trip.count39 = zext nneg i32 %7 to i64
  %wide.trip.count = and i64 %3, 2147483647
  br label %.preheader.us

.preheader.us:                                    ; preds = %.preheader.us.preheader, %17
  %indvars.iv36 = phi i64 [ 0, %.preheader.us.preheader ], [ %indvars.iv.next37, %17 ]
  br label %9

9:                                                ; preds = %.preheader.us, %18
  %indvars.iv = phi i64 [ 0, %.preheader.us ], [ %indvars.iv.next, %18 ]
  %10 = add nuw nsw i64 %indvars.iv, %indvars.iv36
  %11 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %10)
  %12 = load i8, ptr %11, align 1, !tbaa !5
  %13 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %indvars.iv)
  %14 = load i8, ptr %13, align 1, !tbaa !5
  %15 = icmp eq i8 %12, %14
  br i1 %15, label %18, label %.critedge.us

.critedge.us:                                     ; preds = %9
  %16 = trunc nuw nsw i64 %indvars.iv to i32
  %.not.us = icmp eq i32 %16, %4
  br i1 %.not.us, label %.split.us.loopexit, label %17

17:                                               ; preds = %.critedge.us
  %indvars.iv.next37 = add nuw nsw i64 %indvars.iv36, 1
  %exitcond40.not = icmp eq i64 %indvars.iv.next37, %wide.trip.count39
  br i1 %exitcond40.not, label %.thread, label %.preheader.us, !llvm.loop !8

18:                                               ; preds = %9
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %.split.us.loopexit, label %9, !llvm.loop !10

.preheader.lr.ph.split:                           ; preds = %.preheader.lr.ph
  %.not = icmp eq i32 %4, 0
  br i1 %.not, label %.split.us, label %.thread

.thread:                                          ; preds = %17, %.preheader.lr.ph.split, %2
  %19 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull @.str)
  %20 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %19, ptr noundef nonnull @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  br label %.split.us

.split.us.loopexit:                               ; preds = %.critedge.us, %18
  %21 = trunc nuw nsw i64 %indvars.iv36 to i32
  br label %.split.us

.split.us:                                        ; preds = %.split.us.loopexit, %.preheader.lr.ph.split, %.thread
  %.3 = phi i32 [ -1, %.thread ], [ 0, %.preheader.lr.ph.split ], [ %21, %.split.us.loopexit ]
  ret i32 %.3
}

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32)) local_unnamed_addr #1 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 #1 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #0 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #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 = { inlinehint 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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}
!10 = distinct !{!10, !9}


; Effective O3 passes: ConstraintEliminationPass,CorrelatedValuePropagationPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyCFGPass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass