; LLVM IR from UtkarshPathrabe/Competitive-Coding :: Model Algorithms/Divide And Conquer/Number of Strings of Matched Parenthesis/Count_97005ba6 (Z17CountMatchedPairsi)

; 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 noundef i32 @_Z17CountMatchedPairsi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  %6 = load i32, ptr %3, align 4, !tbaa !5
  %7 = icmp eq i32 %6, 0
  br i1 %7, label %8, label %9

8:                                                ; preds = %1
  store i32 1, ptr %2, align 4
  br label %31

9:                                                ; preds = %1
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  store i32 0, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 1, ptr %5, align 4, !tbaa !5
  br label %10

10:                                               ; preds = %26, %9
  %11 = load i32, ptr %5, align 4, !tbaa !5
  %12 = load i32, ptr %3, align 4, !tbaa !5
  %13 = icmp sle i32 %11, %12
  br i1 %13, label %15, label %14

14:                                               ; preds = %10
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  br label %29

15:                                               ; preds = %10
  %16 = load i32, ptr %5, align 4, !tbaa !5
  %17 = sub nsw i32 %16, 1
  %18 = call noundef i32 @_Z17CountMatchedPairsi(i32 noundef %17)
  %19 = load i32, ptr %3, align 4, !tbaa !5
  %20 = load i32, ptr %5, align 4, !tbaa !5
  %21 = sub nsw i32 %19, %20
  %22 = call noundef i32 @_Z17CountMatchedPairsi(i32 noundef %21)
  %23 = mul nsw i32 %18, %22
  %24 = load i32, ptr %4, align 4, !tbaa !5
  %25 = add nsw i32 %24, %23
  store i32 %25, ptr %4, align 4, !tbaa !5
  br label %26

26:                                               ; preds = %15
  %27 = load i32, ptr %5, align 4, !tbaa !5
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %5, align 4, !tbaa !5
  br label %10, !llvm.loop !9

29:                                               ; preds = %14
  %30 = load i32, ptr %4, align 4, !tbaa !5
  store i32 %30, ptr %2, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %31

31:                                               ; preds = %29, %8
  %32 = load i32, ptr %2, align 4
  ret i32 %32
}

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

; 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 = { 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 = distinct !{!9, !10}
!10 = !{!"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 nofree nosync nounwind willreturn memory(none) uwtable
define dso_local noundef i32 @_Z17CountMatchedPairsi(i32 noundef %0) local_unnamed_addr #0 {
  %2 = icmp eq i32 %0, 0
  br i1 %2, label %.loopexit, label %.preheader

.preheader:                                       ; preds = %1
  %.not13 = icmp slt i32 %0, 1
  br i1 %.not13, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %.015 = phi i32 [ %9, %.lr.ph ], [ 1, %.preheader ]
  %.01014 = phi i32 [ %8, %.lr.ph ], [ 0, %.preheader ]
  %3 = add nsw i32 %.015, -1
  %4 = tail call noundef i32 @_Z17CountMatchedPairsi(i32 noundef %3)
  %5 = sub nsw i32 %0, %.015
  %6 = tail call noundef i32 @_Z17CountMatchedPairsi(i32 noundef %5)
  %7 = mul nsw i32 %6, %4
  %8 = add nsw i32 %7, %.01014
  %9 = add nuw i32 %.015, 1
  %exitcond.not = icmp eq i32 %.015, %0
  br i1 %exitcond.not, label %.loopexit, label %.lr.ph, !llvm.loop !5

.loopexit:                                        ; preds = %.lr.ph, %.preheader, %1
  %.011 = phi i32 [ 1, %1 ], [ 0, %.preheader ], [ %8, %.lr.ph ]
  ret i32 %.011
}

attributes #0 = { mustprogress nofree nosync nounwind willreturn memory(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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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