; LLVM IR from JanaSabuj/cppdump :: Old/DP/fibonacci_memoized.ll (Z3fibi)

; 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"

@arr = external dso_local global [51 x i32], align 16

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z3fibi(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 sle i32 %4, 1
  br i1 %5, label %6, label %8

6:                                                ; preds = %1
  %7 = load i32, ptr %3, align 4, !tbaa !5
  store i32 %7, ptr %2, align 4
  br label %34

8:                                                ; preds = %1
  %9 = load i32, ptr %3, align 4, !tbaa !5
  %10 = sext i32 %9 to i64
  %11 = getelementptr inbounds [51 x i32], ptr @arr, i64 0, i64 %10
  %12 = load i32, ptr %11, align 4, !tbaa !5
  %13 = icmp ne i32 %12, 0
  br i1 %13, label %14, label %19

14:                                               ; preds = %8
  %15 = load i32, ptr %3, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [51 x i32], ptr @arr, i64 0, i64 %16
  %18 = load i32, ptr %17, align 4, !tbaa !5
  store i32 %18, ptr %2, align 4
  br label %34

19:                                               ; preds = %8
  %20 = load i32, ptr %3, align 4, !tbaa !5
  %21 = sub nsw i32 %20, 1
  %22 = call noundef i32 @_Z3fibi(i32 noundef %21)
  %23 = load i32, ptr %3, align 4, !tbaa !5
  %24 = sub nsw i32 %23, 2
  %25 = call noundef i32 @_Z3fibi(i32 noundef %24)
  %26 = add nsw i32 %22, %25
  %27 = load i32, ptr %3, align 4, !tbaa !5
  %28 = sext i32 %27 to i64
  %29 = getelementptr inbounds [51 x i32], ptr @arr, i64 0, i64 %28
  store i32 %26, ptr %29, align 4, !tbaa !5
  %30 = load i32, ptr %3, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [51 x i32], ptr @arr, i64 0, i64 %31
  %33 = load i32, ptr %32, align 4, !tbaa !5
  store i32 %33, ptr %2, align 4
  br label %34

34:                                               ; preds = %19, %14, %6
  %35 = load i32, ptr %2, align 4
  ret i32 %35
}

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"

@arr = external dso_local local_unnamed_addr global [51 x i32], align 16

; Function Attrs: mustprogress nofree nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef i32 @_Z3fibi(i32 noundef %0) local_unnamed_addr #0 {
  %2 = icmp slt i32 %0, 2
  br i1 %2, label %common.ret11, label %3

3:                                                ; preds = %1
  %4 = zext nneg i32 %0 to i64
  %5 = getelementptr inbounds [51 x i32], ptr @arr, i64 0, i64 %4
  %6 = load i32, ptr %5, align 4, !tbaa !5
  %.not = icmp eq i32 %6, 0
  br i1 %.not, label %7, label %common.ret11

common.ret11:                                     ; preds = %3, %1, %7
  %common.ret11.op = phi i32 [ %12, %7 ], [ %0, %1 ], [ %6, %3 ]
  ret i32 %common.ret11.op

7:                                                ; preds = %3
  %8 = add nsw i32 %0, -1
  %9 = tail call noundef i32 @_Z3fibi(i32 noundef %8)
  %10 = add nsw i32 %0, -2
  %11 = tail call noundef i32 @_Z3fibi(i32 noundef %10)
  %12 = add nsw i32 %11, %9
  store i32 %12, ptr %5, align 4, !tbaa !5
  br label %common.ret11
}

attributes #0 = { mustprogress nofree nosync nounwind memory(readwrite, argmem: none, 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}


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