; LLVM IR from begeekmyfriend/leetcode :: 0050_pow (pow)

; 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 @fast_pow(double noundef %0, i32 noundef %1) #0 {
  %3 = alloca double, align 8
  %4 = alloca double, align 8
  %5 = alloca i32, align 4
  %6 = alloca double, align 8
  store double %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  %7 = load i32, ptr %5, align 4, !tbaa !9
  %8 = icmp eq i32 %7, 0
  br i1 %8, label %9, label %10

9:                                                ; preds = %2
  store double 1.000000e+00, ptr %3, align 8
  br label %35

10:                                               ; preds = %2
  %11 = load i32, ptr %5, align 4, !tbaa !9
  %12 = icmp eq i32 %11, 1
  br i1 %12, label %13, label %15

13:                                               ; preds = %10
  %14 = load double, ptr %4, align 8, !tbaa !5
  store double %14, ptr %3, align 8
  br label %35

15:                                               ; preds = %10
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  %16 = load double, ptr %4, align 8, !tbaa !5
  %17 = load i32, ptr %5, align 4, !tbaa !9
  %18 = sdiv i32 %17, 2
  %19 = call double @fast_pow(double noundef %16, i32 noundef %18)
  store double %19, ptr %6, align 8, !tbaa !5
  %20 = load i32, ptr %5, align 4, !tbaa !9
  %21 = and i32 %20, 1
  %22 = icmp ne i32 %21, 0
  br i1 %22, label %23, label %29

23:                                               ; preds = %15
  %24 = load double, ptr %6, align 8, !tbaa !5
  %25 = load double, ptr %6, align 8, !tbaa !5
  %26 = fmul double %24, %25
  %27 = load double, ptr %4, align 8, !tbaa !5
  %28 = fmul double %26, %27
  br label %33

29:                                               ; preds = %15
  %30 = load double, ptr %6, align 8, !tbaa !5
  %31 = load double, ptr %6, align 8, !tbaa !5
  %32 = fmul double %30, %31
  br label %33

33:                                               ; preds = %29, %23
  %34 = phi double [ %28, %23 ], [ %32, %29 ]
  store double %34, ptr %3, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  br label %35

35:                                               ; preds = %33, %13, %9
  %36 = load double, ptr %3, align 8
  ret double %36
}

; 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 = { 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 #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 = !{!"double", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}


; 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 @fast_pow(double noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  switch i32 %1, label %4 [
    i32 0, label %common.ret12
    i32 1, label %3
  ]

3:                                                ; preds = %2
  br label %common.ret12

common.ret12:                                     ; preds = %2, %3, %4
  %common.ret12.op = phi double [ %10, %4 ], [ %0, %3 ], [ 1.000000e+00, %2 ]
  ret double %common.ret12.op

4:                                                ; preds = %2
  %5 = sdiv i32 %1, 2
  %6 = tail call double @fast_pow(double noundef %0, i32 noundef %5)
  %7 = and i32 %1, 1
  %.not = icmp eq i32 %7, 0
  %8 = fmul double %6, %6
  %9 = fmul double %8, %0
  %10 = select i1 %.not, double %8, double %9
  br label %common.ret12
}

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: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass