; LLVM IR from kazunetakahashi/atcoder :: 2018/0421_ARC096/E.ll (Z13power_2_powerx)

; 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"

@MOD = external dso_local global i64, align 8

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress uwtable
define dso_local noundef i64 @_Z13power_2_powerx(i64 noundef %0) #1 {
  %2 = alloca i64, align 8
  %3 = alloca i64, align 8
  %4 = alloca i64, align 8
  store i64 %0, ptr %3, align 8, !tbaa !5
  %5 = load i64, ptr %3, align 8, !tbaa !5
  %6 = icmp eq i64 %5, 0
  br i1 %6, label %7, label %10

7:                                                ; preds = %1
  %8 = load i64, ptr @MOD, align 8, !tbaa !5
  %9 = srem i64 2, %8
  store i64 %9, ptr %2, align 8
  br label %19

10:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  %11 = load i64, ptr %3, align 8, !tbaa !5
  %12 = sub nsw i64 %11, 1
  %13 = call noundef i64 @_Z13power_2_powerx(i64 noundef %12)
  store i64 %13, ptr %4, align 8, !tbaa !5
  %14 = load i64, ptr %4, align 8, !tbaa !5
  %15 = load i64, ptr %4, align 8, !tbaa !5
  %16 = mul nsw i64 %14, %15
  %17 = load i64, ptr @MOD, align 8, !tbaa !5
  %18 = srem i64 %16, %17
  store i64 %18, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  br label %19

19:                                               ; preds = %10, %7
  %20 = load i64, ptr %2, align 8
  ret i64 %20
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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 = !{!"long long", !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"

@MOD = external dso_local local_unnamed_addr global i64, align 8

; Function Attrs: mustprogress nofree nosync nounwind willreturn memory(read, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef i64 @_Z13power_2_powerx(i64 noundef %0) local_unnamed_addr #0 {
  %2 = icmp eq i64 %0, 0
  br i1 %2, label %common.ret, label %5

common.ret:                                       ; preds = %1, %5
  %.sink = phi i64 [ %8, %5 ], [ 2, %1 ]
  %3 = load i64, ptr @MOD, align 8, !tbaa !5
  %4 = srem i64 %.sink, %3
  ret i64 %4

5:                                                ; preds = %1
  %6 = add nsw i64 %0, -1
  %7 = tail call noundef i64 @_Z13power_2_powerx(i64 noundef %6)
  %8 = mul nsw i64 %7, %7
  br label %common.ret
}

attributes #0 = { mustprogress nofree nosync nounwind willreturn memory(read, 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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}


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