; LLVM IR from ravireddy07/cpp-book :: src/Coding-Blocks/FriendsPairing_ori.ll (Z7friendsi)

; 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 @_Z7friendsi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  %4 = load i32, ptr %3, align 4, !tbaa !5
  %5 = icmp eq i32 %4, 0
  br i1 %5, label %9, label %6

6:                                                ; preds = %1
  %7 = load i32, ptr %3, align 4, !tbaa !5
  %8 = icmp eq i32 %7, 1
  br i1 %8, label %9, label %10

9:                                                ; preds = %6, %1
  store i32 1, ptr %2, align 4
  br label %25

10:                                               ; preds = %6
  %11 = load i32, ptr %3, align 4, !tbaa !5
  %12 = icmp eq i32 %11, 2
  br i1 %12, label %13, label %14

13:                                               ; preds = %10
  store i32 2, ptr %2, align 4
  br label %25

14:                                               ; preds = %10
  %15 = load i32, ptr %3, align 4, !tbaa !5
  %16 = sub nsw i32 %15, 1
  %17 = call noundef i32 @_Z7friendsi(i32 noundef %16)
  %18 = load i32, ptr %3, align 4, !tbaa !5
  %19 = sub nsw i32 %18, 1
  %20 = load i32, ptr %3, align 4, !tbaa !5
  %21 = sub nsw i32 %20, 2
  %22 = call noundef i32 @_Z7friendsi(i32 noundef %21)
  %23 = mul nsw i32 %19, %22
  %24 = add nsw i32 %17, %23
  store i32 %24, ptr %2, align 4
  br label %25

25:                                               ; preds = %14, %13, %9
  %26 = load i32, ptr %2, align 4
  ret i32 %26
}

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" }

!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"}


; 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 @_Z7friendsi(i32 noundef %0) local_unnamed_addr #0 {
  %or.cond = icmp ult i32 %0, 2
  br i1 %or.cond, label %common.ret9, label %2

2:                                                ; preds = %1
  %3 = icmp eq i32 %0, 2
  br i1 %3, label %common.ret9, label %4

common.ret9:                                      ; preds = %2, %1, %4
  %common.ret9.op = phi i32 [ %10, %4 ], [ 1, %1 ], [ 2, %2 ]
  ret i32 %common.ret9.op

4:                                                ; preds = %2
  %5 = add nsw i32 %0, -1
  %6 = tail call noundef i32 @_Z7friendsi(i32 noundef %5)
  %7 = add nsw i32 %0, -2
  %8 = tail call noundef i32 @_Z7friendsi(i32 noundef %7)
  %9 = mul nsw i32 %8, %5
  %10 = add nsw i32 %9, %6
  br label %common.ret9
}

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)"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,IPSCCPPass,InstCombinePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass