; LLVM IR from evanxg852000/rockstartdev :: modern-cpp (lc3)

; 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"

%struct.fd_set = type { [16 x i64] }
%struct.timeval = type { i64, i64 }

; 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: nounwind uwtable
define dso_local zeroext i16 @check_key() #1 {
  %1 = alloca %struct.fd_set, align 8
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca %struct.timeval, align 8
  call void @llvm.lifetime.start.p0(i64 128, ptr %1) #3
  br label %5

5:                                                ; preds = %0
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  store ptr %1, ptr %3, align 8, !tbaa !5
  store i32 0, ptr %2, align 4, !tbaa !9
  br label %6

6:                                                ; preds = %16, %5
  %7 = load i32, ptr %2, align 4, !tbaa !9
  %8 = zext i32 %7 to i64
  %9 = icmp ult i64 %8, 16
  br i1 %9, label %10, label %19

10:                                               ; preds = %6
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  %12 = getelementptr inbounds %struct.fd_set, ptr %11, i32 0, i32 0
  %13 = load i32, ptr %2, align 4, !tbaa !9
  %14 = zext i32 %13 to i64
  %15 = getelementptr inbounds [16 x i64], ptr %12, i64 0, i64 %14
  store i64 0, ptr %15, align 8, !tbaa !11
  br label %16

16:                                               ; preds = %10
  %17 = load i32, ptr %2, align 4, !tbaa !9
  %18 = add i32 %17, 1
  store i32 %18, ptr %2, align 4, !tbaa !9
  br label %6, !llvm.loop !13

19:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  br label %20

20:                                               ; preds = %19
  br label %21

21:                                               ; preds = %20
  %22 = getelementptr inbounds %struct.fd_set, ptr %1, i32 0, i32 0
  %23 = getelementptr inbounds [16 x i64], ptr %22, i64 0, i64 0
  %24 = load i64, ptr %23, align 8, !tbaa !11
  %25 = or i64 %24, 1
  store i64 %25, ptr %23, align 8, !tbaa !11
  call void @llvm.lifetime.start.p0(i64 16, ptr %4) #3
  %26 = getelementptr inbounds %struct.timeval, ptr %4, i32 0, i32 0
  store i64 0, ptr %26, align 8, !tbaa !15
  %27 = getelementptr inbounds %struct.timeval, ptr %4, i32 0, i32 1
  store i64 0, ptr %27, align 8, !tbaa !17
  %28 = call i32 @select(i32 noundef 1, ptr noundef %1, ptr noundef null, ptr noundef null, ptr noundef %4)
  %29 = icmp ne i32 %28, 0
  %30 = zext i1 %29 to i32
  %31 = trunc i32 %30 to i16
  call void @llvm.lifetime.end.p0(i64 16, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 128, ptr %1) #3
  ret i16 %31
}

declare i32 @select(i32 noundef, ptr noundef, ptr noundef, ptr noundef, ptr noundef) #2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #2 = { "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 #3 = { 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !12, i64 0}
!12 = !{!"long", !7, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = !{!16, !12, i64 0}
!16 = !{!"timeval", !12, i64 0, !12, i64 8}
!17 = !{!16, !12, i64 8}


; 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"

%struct.fd_set = type { [16 x i64] }
%struct.timeval = type { i64, i64 }

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

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

; Function Attrs: nounwind uwtable
define dso_local zeroext range(i16 0, 2) i16 @check_key() local_unnamed_addr #1 {
  %1 = alloca %struct.fd_set, align 8
  %2 = alloca %struct.timeval, align 8
  call void @llvm.lifetime.start.p0(i64 128, ptr nonnull %1) #4
  %3 = getelementptr inbounds i8, ptr %1, i64 8
  call void @llvm.memset.p0.i64(ptr noundef nonnull align 8 dereferenceable(128) %3, i8 0, i64 120, i1 false), !tbaa !5
  store i64 1, ptr %1, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %2) #4
  call void @llvm.memset.p0.i64(ptr noundef nonnull align 8 dereferenceable(16) %2, i8 0, i64 16, i1 false)
  %4 = call i32 @select(i32 noundef 1, ptr noundef nonnull %1, ptr noundef null, ptr noundef null, ptr noundef nonnull %2) #4
  %5 = icmp ne i32 %4, 0
  %6 = zext i1 %5 to i16
  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %2) #4
  call void @llvm.lifetime.end.p0(i64 128, ptr nonnull %1) #4
  ret i16 %6
}

declare i32 @select(i32 noundef, ptr noundef, ptr noundef, ptr noundef, ptr noundef) local_unnamed_addr #2

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #3

attributes #0 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #2 = { "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 #3 = { nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #4 = { 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", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}


; Effective O3 passes: CorrelatedValuePropagationPass,DSEPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,LoopIdiomRecognizePass,LoopRotatePass,MemCpyOptPass,SROAPass,SimplifyCFGPass