; LLVM IR from codee-com/open-catalog :: Checks/PWR018 (example)

; 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: nounwind uwtable
define dso_local double @fib(i32 noundef %0) #0 {
  %2 = alloca double, align 8
  %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 %6, label %7

6:                                                ; preds = %1
  store double 0.000000e+00, ptr %2, align 8
  br label %19

7:                                                ; preds = %1
  %8 = load i32, ptr %3, align 4, !tbaa !5
  %9 = icmp eq i32 %8, 1
  br i1 %9, label %10, label %11

10:                                               ; preds = %7
  store double 1.000000e+00, ptr %2, align 8
  br label %19

11:                                               ; preds = %7
  %12 = load i32, ptr %3, align 4, !tbaa !5
  %13 = sub i32 %12, 1
  %14 = call double @fib(i32 noundef %13)
  %15 = load i32, ptr %3, align 4, !tbaa !5
  %16 = sub i32 %15, 2
  %17 = call double @fib(i32 noundef %16)
  %18 = fadd double %14, %17
  store double %18, ptr %2, align 8
  br label %19

19:                                               ; preds = %11, %10, %6
  %20 = load double, ptr %2, align 8
  ret double %20
}

attributes #0 = { 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" }

!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/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: nofree nosync nounwind memory(none) uwtable
define dso_local double @fib(i32 noundef %0) local_unnamed_addr #0 {
  switch i32 %0, label %3 [
    i32 0, label %common.ret5
    i32 1, label %2
  ]

2:                                                ; preds = %1
  br label %common.ret5

common.ret5:                                      ; preds = %1, %2, %3
  %common.ret5.op = phi double [ %8, %3 ], [ 1.000000e+00, %2 ], [ 0.000000e+00, %1 ]
  ret double %common.ret5.op

3:                                                ; preds = %1
  %4 = add i32 %0, -1
  %5 = tail call double @fib(i32 noundef %4)
  %6 = add i32 %0, -2
  %7 = tail call double @fib(i32 noundef %6)
  %8 = fadd double %5, %7
  br label %common.ret5
}

attributes #0 = { nofree nosync nounwind 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: GlobalOptPass,IPSCCPPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass