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diff --git a/KDBG/Machine.impl.hpp b/KDBG/Machine.impl.hpp
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-//
-//  Machine.impl.hpp
-//  KDBG
-//
-//  Created by James McIlree on 10/30/12.
-//  Copyright (c) 2014 Apple. All rights reserved.
-//
-
-#include "KDebug.h"
-
-template <typename SIZE>
-bool process_by_time_sort(const MachineProcess<SIZE>* left, const MachineProcess<SIZE>* right) {
-    return left->timespan().location() < right->timespan().location();
-}
-
-template <typename SIZE>
-bool thread_by_time_sort(const MachineThread<SIZE>* left, const MachineThread<SIZE>* right) {
-    return left->timespan().location() < right->timespan().location();
-}
-
-template <typename SIZE>
-void Machine<SIZE>::post_initialize() {
-    //
-    // Post initialization. Sort various by time vectors, etc.
-    //
-
-    std::sort(_processes_by_time.begin(), _processes_by_time.end(), process_by_time_sort<SIZE>);
-    std::sort(_threads_by_time.begin(), _threads_by_time.end(), thread_by_time_sort<SIZE>);
-
-    // naked auto okay here, process is a ptr.
-    AbsTime last_machine_timestamp = _events[_event_count-1].timestamp();
-    for (auto process : _processes_by_time) {
-       process->post_initialize(last_machine_timestamp);
-    }
-
-    //
-    // Collapse the idle/intr/run queues into a single timeline
-    //
-    for (auto& cpu : _cpus) {
-       cpu.post_initialize(timespan());
-    }
-
-    //
-    // Flush any outstanding blocked events
-    //
-    for (auto& thread : _threads_by_tid) {
-       thread.second.post_initialize(last_machine_timestamp);
-    }
-
-    //
-    // Sort the IOActivity events, and build a flattened vector that can be used to find IO ranges for intersecting during interval searches
-    //
-    _io_by_uid.clear();
-    std::sort(_all_io.begin(), _all_io.end());
-
-    // We cannot use trange_vector_union to flatten _all_io, as _all_io isn't a plain TRange<AbsTime> type, and we want to yield that type.
-    // cut & paste to the rescue! :-)
-    if (!_all_io.empty()) {
-       auto input_it = _all_io.begin();
-       _all_io_active_intervals.push_back(*input_it);
-       while (++input_it < _all_io.end()) {
-           TRange<AbsTime> union_range = _all_io_active_intervals.back();
-
-           if (union_range.intersects(*input_it)) {
-               _all_io_active_intervals.pop_back();
-               _all_io_active_intervals.push_back(union_range.union_range(*input_it));
-           } else {
-               ASSERT(union_range < *input_it, "Out of order merging");
-               _all_io_active_intervals.push_back(*input_it);
-           }
-       }
-    }
-
-    //
-    // Flush any outstanding MachMsg(s) in the nursery (state SEND)
-    //
-    // NOTE! We do not clear _mach_msg_nursery because its state is
-    // forwarded to future Machine(s).
-    //
-    for (auto& nursery_it : _mach_msg_nursery) {
-       auto& nursery_msg = nursery_it.second;
-       if (nursery_msg.state() == kNurseryMachMsgState::Send) {
-           auto mach_msg_it = _mach_msgs.emplace(_mach_msgs.end(),
-                                                 nursery_msg.id(),
-                                                 nursery_msg.kmsg_addr(),
-                                                 kMachineMachMsgFlag::HasSender,
-                                                 nursery_msg.send_time(),
-                                                 nursery_msg.send_tid(),
-                                                 nursery_msg.send_msgh_bits(),
-                                                 nursery_msg.send_voucher(),
-                                                 AbsTime(0),
-                                                 0,
-                                                 0,
-                                                 &Machine<SIZE>::UnsetVoucher);
-           _mach_msgs_by_event_index[nursery_msg.send_event_index()] = std::distance(_mach_msgs.begin(), mach_msg_it);
-       }
-    }
-
-    //
-    // Flush any outstanding Voucher(s) in the nursery
-    //
-    for (auto& nursery_it : _voucher_nursery) {
-
-       //
-       // First we need to "close" the open end of the live voucher's
-       // timespan.
-       //
-       auto voucher = nursery_it.second.get();
-       voucher->set_timespan_to_end_of_time();
-
-       auto address = nursery_it.first;
-
-       // First find the "row" for this address.
-       auto by_addr_it = _vouchers_by_addr.find(address);
-       if (by_addr_it == _vouchers_by_addr.end()) {
-           // No address entry case
-           std::vector<std::unique_ptr<MachineVoucher<SIZE>>> row;
-           row.emplace_back(std::move(nursery_it.second));
-           _vouchers_by_addr.emplace(address, std::move(row));
-       } else {
-           auto& row = by_addr_it->second;
-
-           // Make sure these are sorted and non-overlapping
-           ASSERT(row.back()->timespan() < voucher->timespan(), "Sanity");
-           ASSERT(!row.back()->timespan().intersects(voucher->timespan()), "Sanity");
-
-           row.emplace_back(std::move(nursery_it.second));
-       }
-    }
-
-    _voucher_nursery.clear();
-
-    DEBUG_ONLY(validate());
-}
-
-template <typename SIZE>
-void Machine<SIZE>::raw_initialize(const KDCPUMapEntry* cpumaps,
-                                  uint32_t cpumap_count,
-                                  const KDThreadMapEntry<SIZE>* threadmaps,
-                                  uint32_t threadmap_count,
-                                  const KDEvent<SIZE>* events,
-                                  uintptr_t event_count)
-{
-    ASSERT(cpumaps || cpumap_count == 0, "Sanity");
-    ASSERT(threadmaps || threadmap_count == 0, "Sanity");
-    ASSERT(events || event_count == 0, "Sanity");
-
-    for (uint32_t i = 0; i < cpumap_count; ++i) {
-       _cpus.emplace_back(i, cpumaps[i].is_iop(), cpumaps[i].name());
-    }
-
-    // We cannot create processes / threads unless we have at least one event to give us a timestamp.
-    if (event_count) {
-       AbsTime now = events[0].timestamp();
-
-       _kernel_task = create_process(0, "kernel_task", now, kMachineProcessFlag::IsKernelProcess);
-
-       // Initial thread state, nothing in nusery
-       for (uint32_t index = 0; index < threadmap_count; ++index) {
-           auto& threadmap = threadmaps[index];
-
-           pid_t pid = threadmap.pid();
-
-           // The kernel threadmap often has empty entries. Skip them.
-           if (pid == 0)
-               break;
-
-           if (pid == 1 && strncmp(threadmap.name(), "kernel_task", 12) == 0) {
-               pid = 0;
-           }
-
-           MachineProcess<SIZE>* process = youngest_mutable_process(pid);
-           if (!process) {
-               process = create_process(pid, threadmap.name(), now, kMachineProcessFlag::CreatedByThreadMap);
-               ASSERT(process, "Sanity");
-           }
-           process->add_thread(create_thread(process, threadmap.tid(), &UnsetVoucher, now, kMachineThreadFlag::CreatedByThreadMap));
-       }
-    }
-
-    // We need to know what the idle/INTR states of the CPU's are.
-    initialize_cpu_idle_intr_states();
-
-    for (uintptr_t index = 0; index < event_count; ++index) {
-       if (!process_event(events[index]))
-           break;
-    }
-
-    post_initialize();
-}
-
-template <typename SIZE>
-Machine<SIZE>::Machine(KDCPUMapEntry* cpumaps, uint32_t cpumap_count, KDThreadMapEntry<SIZE>* threadmaps, uint32_t threadmap_count, KDEvent<SIZE>* events, uintptr_t event_count) :
-    _kernel_task(nullptr),
-    _events(events),
-    _event_count(event_count),
-    _flags(0),
-    _unknown_process_pid(-1)
-{
-    raw_initialize(cpumaps,
-                  cpumap_count,
-                  threadmaps,
-                  threadmap_count,
-                  events,
-                  event_count);
-}
-
-template <typename SIZE>
-Machine<SIZE>::Machine(const TraceFile& file) :
-    _kernel_task(nullptr),
-    _events(file.events<SIZE>()),
-    _event_count(file.event_count()),
-    _flags(0),
-    _unknown_process_pid(-1)
-{
-    raw_initialize(file.cpumap(),
-                  file.cpumap_count(),
-                  file.threadmap<SIZE>(),
-                  file.threadmap_count(),
-                  file.events<SIZE>(),
-                  file.event_count());
-}
-
-template <typename SIZE>
-Machine<SIZE>::Machine(Machine<SIZE>& parent, KDEvent<SIZE>* events, uintptr_t event_count) :
-    _kernel_task(nullptr),
-    _events(events),
-    _event_count(event_count),
-    _flags(0),
-    _unknown_process_pid(-1)
-{
-    ASSERT(events || event_count == 0, "Sanity");
-
-    const std::vector<const MachineThread<SIZE>*>& parent_threads = parent.threads();
-    const std::vector<const MachineCPU<SIZE>>& parent_cpus = parent.cpus();
-
-    for (const MachineCPU<SIZE>& parent_cpu : parent_cpus) {
-       _cpus.emplace_back(parent_cpu.id(), parent_cpu.is_iop(), parent_cpu.name());
-    }
-
-    // We cannot create processes / threads unless we have at least one event to give us a timestamp.
-    if (event_count) {
-       AbsTime now = events[0].timestamp();
-
-       //
-       // Forawd any live vouchers. This must done before forwarding threads
-       // or MachMsgs from their nurseries, as they have references to the
-       // vouchers.
-       //
-       for (auto& parent_vouchers_by_addr_it : parent._vouchers_by_addr) {
-           std::unique_ptr<MachineVoucher<SIZE>>& voucher = parent_vouchers_by_addr_it.second.back();
-           if (voucher->is_live()) {
-               // When we flushed these vouchers in the previous machine state,
-               // we set their timespans to infinite. We need to reset them in
-               // case a close event arrives.
-               voucher->set_timespan_to_zero_length();
-               _voucher_nursery.emplace(voucher->address(), std::move(voucher));
-           }
-       }
-
-       _kernel_task = create_process(0, "kernel_task", now, kMachineProcessFlag::IsKernelProcess);
-
-       for (const MachineThread<SIZE>* parent_thread : parent_threads) {
-           if (!parent_thread->is_trace_terminated()) {
-               const MachineProcess<SIZE>& parent_process = parent_thread->process();
-               MachineProcess<SIZE>* new_process = youngest_mutable_process(parent_process.pid());
-               if (!new_process) {
-                   kMachineProcessFlag new_process_flags = (kMachineProcessFlag)(parent_process.flags() | (uint32_t)kMachineProcessFlag::CreatedByPreviousMachineState);
-                   new_process = create_process(parent_process.pid(), parent_process.name(), now, new_process_flags);
-                   ASSERT(new_process, "Sanity");
-               }
-               new_process->add_thread(create_thread(new_process,
-                                                     parent_thread->tid(),
-                                                     thread_forwarding_voucher_lookup(parent_thread->last_voucher()),
-                                                     now,
-                                                     (kMachineThreadFlag)(parent_thread->flags() | (uint32_t)kMachineThreadFlag::CreatedByPreviousMachineState)));
-           }
-       }
-
-       // We need to know what the idle/INTR states of the CPU's are.
-       //
-       // Start by looking at the existing states.
-       uint32_t init_count = 0;
-       uint32_t ap_count = 0;
-       for (const MachineCPU<SIZE>& parent_cpu : parent_cpus) {
-           if (!parent_cpu.is_iop()) {
-               ap_count++;
-               const std::vector<CPUActivity<SIZE>>& parent_cpu_timeline = parent_cpu.timeline();
-
-               bool intr_initialized = false;
-               bool idle_initialized = false;
-               bool runq_initialized = false;
-
-               MachineCPU<SIZE>& cpu = _cpus[parent_cpu.id()];
-
-               for (auto reverse_it = parent_cpu_timeline.rbegin(); reverse_it < parent_cpu_timeline.rend(); ++reverse_it) {
-
-                   // We can sometimes split two simultaneous events across two buffer snaps.
-                   // IOW, buffer snap 1:
-                   //
-                   // event[N].timestamp = 1234;
-                   //
-                   // buffer snap 2:
-                   //
-                   // event[0].timestamp = 1234;
-                   ASSERT(!reverse_it->contains(now) || reverse_it->max()-AbsTime(1) == now, "Sanity");
-                   ASSERT(reverse_it->location() <= now, "Sanity");
-
-                   switch (reverse_it->type()) {
-                       //
-                       // The states are separate, and heirarchical.
-                       // The order (low -> high) is:
-                       // Run, Idle, INTR
-                       // Unknown is a special state; we give up on seeing it.
-                       // A lower state precludes being in a higher state, but
-                       // not vice-versa. You can not be IDLE if you are currently
-                       // Run. You may be IDLE during Run.
-                       //
-
-                       case kCPUActivity::Unknown:
-                           // Don't actually initialize anything, just force a bailout
-                           runq_initialized = idle_initialized = intr_initialized = true;
-                           break;
-
-                       // NOTE NOTE NOTE!
-                       //
-                       // Overly clever here, note the lack of "break" in the Run
-                       // and Idle clause, we fall through to initialize higher
-                       // states.
-                       case kCPUActivity::Run:
-                           ASSERT(!runq_initialized, "This should always be the last level to initialize");
-                           if (MachineThread<SIZE>* on_cpu_thread = youngest_mutable_thread(reverse_it->thread()->tid())) {
-                               cpu.initialize_thread_state(on_cpu_thread, now);
-                               init_count++;
-                           } else {
-                               ASSERT(reverse_it->thread()->is_trace_terminated() , "We should find this thread unless its been removed");
-                           }
-                           runq_initialized = true;
-
-                       case kCPUActivity::Idle:
-                           if (!idle_initialized) {
-                               cpu.initialize_idle_state(reverse_it->is_idle(), now);
-                               init_count++;
-                               idle_initialized = true;
-                           }
-
-                       case kCPUActivity::INTR:
-                           if (!intr_initialized) {
-                               cpu.initialize_intr_state(reverse_it->is_intr(), now);
-                               init_count++;
-                               intr_initialized = true;
-                           }
-                           break;
-                   }
-
-                   if (runq_initialized) {
-                       ASSERT(idle_initialized && intr_initialized, "Sanity");
-                       break;
-                   }
-               }
-           }
-       }
-
-       if (init_count < (ap_count * 3)) {
-           initialize_cpu_idle_intr_states();
-       }
-
-       //
-       // Forward any messages from the nursery
-       //
-
-       for (auto& parent_nursery_it : parent._mach_msg_nursery) {
-           auto& parent_nursery_msg = parent_nursery_it.second;
-
-           switch (parent_nursery_msg.state()) {
-                   // We forward send(s) because they can become receives.
-                   // We forward the free's because they stop us from showing bogus kernel message receipts
-               case kNurseryMachMsgState::Send:
-               case kNurseryMachMsgState::Free: {
-                   ASSERT(_mach_msg_nursery.find(parent_nursery_msg.kmsg_addr()) == _mach_msg_nursery.end(), "Duplicate kmsg address when forwarding mach_msg nursery from parent");
-
-                   auto it = _mach_msg_nursery.emplace(parent_nursery_msg.kmsg_addr(), parent_nursery_msg);
-
-                   // Grr, emplace returns a std::pair<it, bool>, and the it is std::pair<key, value>...
-
-                   // We have to clear this to prevent bogus data being shown during a receive,
-                   // the send event index is no longer available.
-                   it.first->second.set_send_event_index(-1);
-                   break;
-               }
-
-               default:
-                   break;
-           }
-       }
-    }
-
-    for (uintptr_t index = 0; index < event_count; ++index) {
-       if (!process_event(_events[index]))
-           break;
-    }
-
-    post_initialize();
-}
-
-template <typename SIZE>
-const MachineProcess<SIZE>* Machine<SIZE>::process(pid_t pid, AbsTime time) const {
-    auto by_pid_range = _processes_by_pid.equal_range(pid);
-    for (auto it = by_pid_range.first; it != by_pid_range.second; ++it) {
-       const MachineProcess<SIZE>& process = it->second;
-       if (process.timespan().contains(time)) {
-           return &process;
-       }
-    }
-
-    return nullptr;
-}
-
-template <typename SIZE>
-const MachineThread<SIZE>* Machine<SIZE>::thread(typename SIZE::ptr_t tid, AbsTime time) const {
-    auto by_tid_range = _threads_by_tid.equal_range(tid);
-    for (auto it = by_tid_range.first; it != by_tid_range.second; ++it) {
-       const MachineThread<SIZE>& thread = it->second;
-       if (thread.timespan().contains(time)) {
-           return &thread;
-       }
-    }
-
-    return nullptr;
-}
-
-template <typename SIZE>
-struct VoucherVsAbsTimeComparator {
-    bool operator()(const std::unique_ptr<MachineVoucher<SIZE>>& voucher, const AbsTime time) const {
-       return voucher->timespan().max() < time;
-    }
-
-    bool operator()(const AbsTime time, const std::unique_ptr<MachineVoucher<SIZE>>& voucher) const {
-       return time < voucher->timespan().max();
-    }
-};
-
-template <typename SIZE>
-const MachineVoucher<SIZE>* Machine<SIZE>::voucher(typename SIZE::ptr_t address, AbsTime timestamp) const {
-    // First find the "row" for this address.
-    auto by_addr_it = _vouchers_by_addr.find(address);
-    if (by_addr_it != _vouchers_by_addr.end()) {
-       auto& row = by_addr_it->second;
-
-       auto by_time_it = std::upper_bound(row.begin(), row.end(), timestamp, VoucherVsAbsTimeComparator<SIZE>());
-       // The upper bound will report that 0 is lower than [ 10, 20 ), need to check contains!
-       if (by_time_it != row.end()) {
-           // The compiler is having troubles seeing through an iterator that reflects unique_ptr methods which reflects MachineVoucher methods.
-           auto v = by_time_it->get();
-           if (v->timespan().contains(timestamp)) {
-               return v;
-           }
-       }
-    }
-
-    return nullptr;
-}
-
-template <typename SIZE>
-const MachineMachMsg<SIZE>* Machine<SIZE>::mach_msg(uintptr_t event_index) const {
-    auto it = _mach_msgs_by_event_index.find(event_index);
-    if (it != _mach_msgs_by_event_index.end()) {
-       return &_mach_msgs.at(it->second);
-    }
-
-    return nullptr;
-}
-
-#if !defined(NDEBUG) && !defined(NS_BLOCK_ASSERTIONS)
-template <typename SIZE>
-void Machine<SIZE>::validate() const {
-    ASSERT(_events, "Sanity");
-    ASSERT(_event_count, "Sanity");
-
-    //
-    // Event timestamp ordering is already pre-checked, no point in retesting it here.
-    //
-
-    ASSERT(_threads_by_tid.size() == _threads_by_time.size(), "Container views state not in sync");
-    ASSERT(_processes_by_pid.size() == _processes_by_name.size(), "Container views state not in sync");
-    ASSERT(_processes_by_pid.size() == _processes_by_time.size(), "Container views state not in sync");
-
-    for (auto& pair : _processes_by_pid) {
-       auto& process = pair.second;
-       process.validate();
-       AbsInterval process_timespan = process.timespan();
-       for (auto thread : process.threads()) {
-           ASSERT(process_timespan.contains(thread->timespan()), "thread outside process timespan");
-       }
-    }
-
-    for (auto thread_ptr : _threads_by_time) {
-       thread_ptr->validate();
-    }
-
-    //
-    // Make sure no process with the same pid overlaps in time
-    //
-    const MachineProcess<SIZE>* last_process = nullptr;
-    for (auto& pair : _processes_by_pid) {
-       auto& process = pair.second;
-       if (last_process && last_process->pid() == process.pid()) {
-           // The < operator only checks ordering, it is not strict
-           // about overlap. We must check both
-           ASSERT(last_process->timespan() < process.timespan(), "Sanity");
-           ASSERT(!last_process->timespan().intersects(process.timespan()), "Sanity");
-       }
-       last_process = &process;
-    }
-
-    //
-    // Make sure no thread with the same tid overlaps in time
-    //
-    const MachineThread<SIZE>* last_thread = nullptr;
-    for (auto& pair : _threads_by_tid) {
-       auto& thread = pair.second;
-       if (last_thread && last_thread->tid() == thread.tid()) {
-           // The < operator only checks ordering, it is not strict
-           // about overlap. We must check both
-           ASSERT(last_thread->timespan() < thread.timespan(), "Sanity");
-           ASSERT(!last_thread->timespan().intersects(thread.timespan()), "Sanity");
-       }
-       last_thread = &thread;
-    }
-
-    ASSERT(is_trange_vector_sorted_and_non_overlapping(_all_io_active_intervals), "all io search/mask vector fails invariant");
-}
-#endif
-
-template <typename SIZE>
-const std::vector<const MachineProcess<SIZE>*>& Machine<SIZE>::processes() const {
-    return *reinterpret_cast< const std::vector<const MachineProcess<SIZE>*>* >(&_processes_by_time);
-}
-
-template <typename SIZE>
-const std::vector<const MachineThread<SIZE>*>& Machine<SIZE>::threads() const {
-    return *reinterpret_cast< const std::vector<const MachineThread<SIZE>*>* >(&_threads_by_time);
-}
-
-template <typename SIZE>
-const std::vector<const MachineCPU<SIZE>>& Machine<SIZE>::cpus() const {
-    return *reinterpret_cast< const std::vector<const MachineCPU<SIZE>>* >(&_cpus);
-}
-
-template <typename SIZE>
-AbsInterval Machine<SIZE>::timespan() const {
-    if (_event_count) {
-       AbsTime begin(_events[0].timestamp());
-       AbsTime end(_events[_event_count-1].timestamp());
-       return AbsInterval(begin, end - begin + AbsTime(1));
-    }
-
-    return AbsInterval(AbsTime(0),AbsTime(0));
-}
-
-template <typename SIZE>
-CPUSummary<SIZE> Machine<SIZE>::summary_for_timespan(AbsInterval summary_timespan, const MachineCPU<SIZE>* summary_cpu) const {
-    ASSERT(summary_timespan.intersects(timespan()), "Sanity");
-    CPUSummary<SIZE> summary;
-
-    uint32_t ap_cpu_count = 0;
-    for (auto& cpu: _cpus) {
-       // We don't know enough about iops to do anything with them.
-       // Also skip cpus with no activity
-       if (!cpu.is_iop() && cpu.is_active()) {
-           ap_cpu_count++;
-       }
-    }
-
-    bool should_calculate_wallclock_run_time = (summary_cpu == NULL && ap_cpu_count > 1);
-
-    summary.begin_cpu_timeline_walks();
-
-    //
-    // Lots of optimization possibilities here...
-    //
-    // We spend a LOT of time doing the set lookups to map from a thread/process to a ThreadSummary / ProcessSummary.
-    // If we could somehow map directly from thread/process to the summary, this would speed up considerably.
-    //
-
-    for (auto& cpu: _cpus) {
-       // We don't know enough about iops to do anything with them.
-       // Also skip cpus with no activity
-       if (!cpu.is_iop() && cpu.is_active()) {
-           if (summary_cpu == NULL || summary_cpu == &cpu) {
-
-               summary.begin_cpu_timeline_walk(&cpu);
-
-               auto& timeline = cpu.timeline();
-               if (!timeline.empty()) {
-                   AbsInterval timeline_timespan = AbsInterval(timeline.front().location(), timeline.back().max() - timeline.front().location());
-                   AbsInterval trimmed_timespan = summary_timespan.intersection_range(timeline_timespan);
-
-                   summary.incr_active_cpus();
-
-                   auto start = cpu.activity_for_timestamp(trimmed_timespan.location());
-                   auto end = cpu.activity_for_timestamp(trimmed_timespan.max()-AbsTime(1));
-
-                   ASSERT(start && start->contains(trimmed_timespan.location()), "Sanity");
-                   ASSERT(end && end->contains(trimmed_timespan.max()-AbsTime(1)), "Sanity");
-
-                   ProcessSummary<SIZE>* process_summary = NULL;
-                   ThreadSummary<SIZE>* thread_summary = NULL;
-
-                   if (start->is_run() && !start->is_context_switch()) {
-                       const MachineThread<SIZE>* thread_on_cpu = start->thread();
-                       const MachineProcess<SIZE>* process_on_cpu = &thread_on_cpu->process();
-
-                       process_summary = summary.mutable_process_summary(process_on_cpu);
-                       thread_summary = process_summary->mutable_thread_summary(thread_on_cpu);
-                   }
-
-                   // NOTE! <=, not <,  because end is inclusive of data we want to count!
-                   while (start <= end) {
-                       // NOTE! summary_timespan, NOT trimmed_timespan!
-                       AbsInterval t = start->intersection_range(summary_timespan);
-
-                       switch (start->type()) {
-                                                       case kCPUActivity::Unknown:
-                               // Only cpu summaries track unknown time
-                               summary.add_unknown_time(t.length());
-                               break;
-
-                                                       case kCPUActivity::Idle:
-                               summary.add_idle_time(t.length());
-                               summary.add_all_cpus_idle_interval(t);
-                               if (process_summary) process_summary->add_idle_time(t.length());
-                               if (thread_summary) thread_summary->add_idle_time(t.length());
-                               break;
-
-                                                       case kCPUActivity::INTR:
-                               summary.add_intr_time(t.length());
-                               // It might seem like we should add INTR time to the wallclock run time
-                               // for the top level summary, but the concurrency level is calculated as
-                               // Actual / Wallclock, where Actual only counts RUN time. If we add INTR
-                               // the results are skewed.
-                               if (process_summary) process_summary->add_intr_time(t.length());
-                               if (thread_summary) thread_summary->add_intr_time(t.length());
-                               break;
-
-                                                       case kCPUActivity::Run: {
-                                                           // We must reset these each time. Consider the case where we have the following:
-                                                           //
-                                                           // RRRRRRRRIIIIIIIIIIIIIIIIRRRRRRRRRR
-                                                           // ^                ^
-                                                           // CSW              Summary starts here
-                                                           //
-                                                           // The first run seen in the summary will not be a CSW, and yet process/thread summary
-                                                           // are NULL...
-
-                                                           const MachineThread<SIZE>* thread_on_cpu = start->thread();
-                                                           const MachineProcess<SIZE>* process_on_cpu = &thread_on_cpu->process();
-
-                                                           process_summary = summary.mutable_process_summary(process_on_cpu);
-                                                           thread_summary = process_summary->mutable_thread_summary(thread_on_cpu);
-
-                                                           if (start->is_context_switch()) {
-                                                               summary.incr_context_switches();
-                                                               process_summary->incr_context_switches();
-                                                               thread_summary->incr_context_switches();
-                                                           }
-
-                                                           summary.add_run_time(t.length());
-                                                           process_summary->add_run_time(t.length());
-                                                           thread_summary->add_run_time(t.length());
-
-                                                           // We only calculate wallclock run time if there is a chance
-                                                           // it might differ from run time.
-                                                           if (should_calculate_wallclock_run_time) {
-                                                               summary.add_wallclock_run_interval(t);
-                                                               process_summary->add_wallclock_run_interval(t);
-                                                           }
-
-                                                           break;
-                                                       }
-                       }
-
-                       start++;
-                   }
-               }
-
-               summary.end_cpu_timeline_walk(&cpu);
-           }
-       }
-    }
-
-    summary.end_cpu_timeline_walks();
-
-    // We only attempt to calculate future summary data in limited circumstances
-    // There must be enough future data to consistently decide if threads would run in the future.
-    // If the summary_cpu is not "all" we do not attempt to calculate.
-
-    if (summary_cpu == NULL) {
-       AbsInterval future_timespan(summary_timespan.max(), summary_timespan.length() * AbsTime(5));
-       if (future_timespan.intersection_range(timespan()).length() == future_timespan.length()) {
-           for (auto& cpu: _cpus) {
-               // We don't know enough about iops to do anything with them
-               if (!cpu.is_iop()) {
-                   auto& timeline = cpu.timeline();
-
-                   if (!timeline.empty()) {
-                       AbsInterval timeline_timespan = AbsInterval(timeline.front().location(), timeline.back().max() - timeline.front().location());
-                       AbsInterval trimmed_timespan = future_timespan.intersection_range(timeline_timespan);
-
-                       auto start = cpu.activity_for_timestamp(trimmed_timespan.location());
-                       auto end = cpu.activity_for_timestamp(trimmed_timespan.max()-AbsTime(1));
-
-                       ASSERT(start && start->contains(trimmed_timespan.location()), "Sanity");
-                       ASSERT(end && end->contains(trimmed_timespan.max()-AbsTime(1)), "Sanity");
-
-                       ProcessSummary<SIZE>* process_summary = NULL;
-                       ThreadSummary<SIZE>* thread_summary = NULL;
-
-                       // NOTE! <=, not <,  because end is inclusive of data we want to count!
-                       while (start <= end) {
-                                                       // NOTE! future_timespan, NOT trimmed_timespan!
-                                                       AbsInterval t = start->intersection_range(future_timespan);
-
-                                                       switch (start->type()) {
-                                                           case kCPUActivity::Unknown:
-                                                               break;
-
-                                                           case kCPUActivity::Idle:
-                                                               // On idle, we mark the current thread as blocked.
-                                                               if (thread_summary)
-                                                                   thread_summary->set_is_blocked_in_future();
-                                                               break;
-
-                                                           case kCPUActivity::INTR:
-                                                               break;
-
-                                                           case kCPUActivity::Run: {
-                                                               // We must reset these each time. Consider the case where we have the following:
-                                                               //
-                                                               // RRRRRRRRIIIIIIIIIIIIIIIIRRRRRRRRRR
-                                                               // ^                ^
-                                                               // CSW              Summary starts here
-                                                               //
-                                                               // The first run seen in the summary will not be a CSW, and yet process/thread summary
-                                                               // are NULL...
-
-                                                               const MachineThread<SIZE>* thread_on_cpu = start->thread();
-                                                               const MachineProcess<SIZE>* process_on_cpu = &thread_on_cpu->process();
-
-                                                               process_summary = summary.mutable_process_summary(process_on_cpu);
-                                                               thread_summary = process_summary->mutable_thread_summary(thread_on_cpu);
-
-                                                               if (!thread_summary->is_future_initialized()) {
-                                                                   thread_summary->set_future_initialized();
-                                                                   thread_summary->set_total_blocked_in_summary(thread_on_cpu->blocked_in_timespan(summary_timespan));
-                                                                   thread_summary->set_first_block_after_summary(thread_on_cpu->next_blocked_after(summary_timespan.max()));
-                                                                   ASSERT(thread_summary->total_blocked_in_summary() + thread_summary->total_run_time() <= summary_timespan.length(), "More time blocked + running than is possible in summary timespan");
-                                                                   thread_summary->set_max_possible_future_run_time(summary_timespan.length() - (thread_summary->total_blocked_in_summary() + thread_summary->total_run_time()));
-                                                               }
-
-                                                               if (!thread_summary->is_blocked_in_future()) {
-                                                                   // We ONLY block at context_switch locations. But, we can context
-                                                                   // switch on any cpu. So, need a strong check!
-                                                                   if (t.max() >= thread_summary->first_block_after_summary()) {
-                                                                       thread_summary->set_is_blocked_in_future();
-                                                                   } else {
-                                                                       ASSERT(t.location() <= thread_summary->first_block_after_summary(), "Sanity");
-                                                                       // Each thread controls how much time it can accumulate in a given window.
-                                                                       // It may be that only a fraction (or none) of the time can be added.
-                                                                       // Make sure to only add the thread approved amount to the process and total summary
-                                                                       AbsTime future_time = thread_summary->add_future_run_time(t.length());
-                                                                       summary.add_future_run_time(future_time);
-                                                                       process_summary->add_future_run_time(future_time);
-                                                                   }
-                                                               }
-                                                               break;
-                                                           }
-                                                       }
-                                                       start++;
-                       }
-                   }
-               }
-           }
-
-           //
-           // When we're doing future run predictions, we can create summaries for
-           // threads that have no run time, and no future run time.
-           //
-           // The way this happens is you have 2 or more cpus.
-           // On cpu 1, there is a blocking event for Thread T at time x.
-           //
-           // While walking through cpu 2's activity, you see T
-           // scheduled at x + N. You cannot add to T's future run
-           // time, and T never ran in the original time window.
-           // Thus, T is added and does nothing.
-           //
-
-           // Remove inactive threads/processes.
-           auto& process_summaries = summary.mutable_process_summaries();
-           auto process_it = process_summaries.begin();
-           while (process_it != process_summaries.end()) {
-               auto next_process_it = process_it;
-               ++next_process_it;
-               if (process_it->total_run_time() == 0 && process_it->total_future_run_time() == 0) {
-                   DEBUG_ONLY({
-                       for (auto& thread_summary : process_it->thread_summaries()) {
-                                                       ASSERT(thread_summary.total_run_time() == 0 && thread_summary.total_future_run_time() == 0, "Process with 0 run time && 0 future run time has thread with non zero values");
-                       }
-                   });
-                   process_summaries.erase(process_it);
-               } else {
-                   // Our evil friend unordered_set returns const iterators...
-                   auto& thread_summaries = const_cast<ProcessSummary<SIZE>*>(&*process_it)->mutable_thread_summaries();
-                   auto thread_it = thread_summaries.begin();
-                   while (thread_it != thread_summaries.end()) {
-                       auto next_thread_it = thread_it;
-                       ++next_thread_it;
-                       if (thread_it->total_run_time() == 0 && thread_it->total_future_run_time() == 0) {
-                                                       thread_summaries.erase(thread_it);
-                       }
-                       thread_it = next_thread_it;
-                   }
-               }
-               process_it = next_process_it;
-           }
-       }
-    }
-
-    //
-    // Calculate vmfault data.
-    //
-    // We want to calculate this after the future CPU time, because it is possible a time slice might have vmfaults
-    // that span the entire timespan. This could result in a process/thread with no run time, and no future time, which
-    // would be removed as "inactive" during future CPU time calculation.
-    //
-
-    if (summary_cpu == NULL) {
-       // vmfault intervals are stored in the MachineThread
-       for (MachineThread<SIZE>* machine_thread : _threads_by_time) {
-           const MachineProcess<SIZE>* process = &machine_thread->process();
-
-           ProcessSummary<SIZE>* process_summary = NULL;
-           ThreadSummary<SIZE>* thread_summary = NULL;
-
-           const auto& vm_faults = machine_thread->vm_faults();
-           if (!vm_faults.empty()) {
-               AbsInterval vm_faults_timespan = AbsInterval(vm_faults.front().location(), vm_faults.back().max() - vm_faults.front().location());
-               AbsInterval trimmed_timespan = summary_timespan.intersection_range(vm_faults_timespan);
-
-               if (trimmed_timespan.length() > 0) {
-                   auto start = interval_beginning_timespan(vm_faults, trimmed_timespan);
-                   auto end = interval_ending_timespan(vm_faults, trimmed_timespan);
-
-                   ASSERT(!start || start->intersects(trimmed_timespan), "Sanity");
-                   ASSERT(!end || end->intersects(trimmed_timespan), "Sanity");
-                   ASSERT((!start && !end) || ((start && end) && (start <= end)), "Sanity");
-
-                   if (start && end) {
-                       // NOTE! <=, not <,  because end is inclusive of data we want to count!
-                       while (start <= end) {
-                                                       //
-                                                       // NOTE! summary_timespan, NOT trimmed_timespan!
-                                                       //
-                                                       // 8/25/13 ... Okay, why do we care summary vs trimmed?
-                                                       // It shouldn't be possible for start to lie outside trimmed...
-                                                       // Leaving this for now rather than introducing some bizzare
-                                                       // corner case, but wth...
-                                                       //
-                                                       AbsInterval t = start->intersection_range(summary_timespan);
-
-                                                       ASSERT(t.length() > 0, "Might be too strong, but expecting this to be non-zero");
-
-                                                       summary.add_vm_fault_time(t.length());
-
-                                                       // We must initialize these lazily. If we don't, every process and thread gets
-                                                       // a summary entry. But we don't want to keep looking them up over and over...
-                                                       if (!process_summary) {
-                                                           process_summary = summary.mutable_process_summary(process);
-                                                       }
-                                                       process_summary->add_vm_fault_time(t.length());
-
-                                                       if (!thread_summary) {
-                                                           thread_summary = process_summary->mutable_thread_summary(machine_thread);
-                                                       }
-                                                       thread_summary->add_vm_fault_time(t.length());
-
-                                                       start++;
-                       }
-                   }
-               }
-           }
-       }
-    }
-
-
-    //
-    // Calculate IO activity data.
-    //
-    if (summary_cpu == NULL) {
-       //
-       // IO activity may overlap on even individual threads.
-       //
-       // All IO activity is stored in a single sorted vector, but
-       // it may overlap even at the thread level. There isn't an
-       // easy way to locate a starting and stopping point that intersect
-       // a given range.
-       //
-       // The solution being used is to flatten the overlapping IO
-       // and keep a sorted non overlapping list of IO activity. For any
-       // given timespan, we find the overlapping intervals of flattened
-       // IO activity and then look up the actual matching IOActivity
-       // objects.
-       //
-       if (!_all_io_active_intervals.empty()) {
-           AbsInterval io_timespan = AbsInterval(_all_io_active_intervals.front().location(), _all_io_active_intervals.back().max() - _all_io_active_intervals.front().location());
-           AbsInterval trimmed_timespan = summary_timespan.intersection_range(io_timespan);
-           if (trimmed_timespan.length() > 0) {
-               //
-               // First find the flattened start point
-               //
-               if (auto flattened_start = interval_beginning_timespan(_all_io_active_intervals, trimmed_timespan)) {
-                   //
-                   // Now find the actual start IOActivity
-                   //
-                   auto it = std::lower_bound(_all_io.begin(), _all_io.end(), flattened_start->location(), AbsIntervalLocationVsAbsTimeComparator());
-                   ASSERT(it != _all_io.end(), "If we reach here, we should ALWAYS find a match!");
-
-                   // We need <= in case there are multiple IOActivities ending at the same time
-                   while (it != _all_io.end() && it->location() < summary_timespan.max()) {
-                       AbsInterval t = it->intersection_range(summary_timespan);
-
-                       // Some of the ranges will not intersect at all, for example
-                       //
-                       // IOActivity
-                       //
-                       //      XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
-                       //         XXXXXX
-                       //                      XXXXXXXX
-                       //
-                       // Summary Range
-                       //
-                       //                          SSSSSSSSSSSSSSSSSS
-                       //
-                       // The flattened_start will point at the oldest IOActivity
-                       // which overlaps the summary range, but many of the later
-                       // IOActivities will not overlap.
-
-                       if (t.length() > 0) {
-                                                       //
-                                                       // Wait time.
-                                                       //
-                                                       summary.add_io_time(t.length());
-
-                                                       ProcessSummary<SIZE>* process_summary = summary.mutable_process_summary(&it->thread()->process());
-                                                       process_summary->add_io_time(t.length());
-
-                                                       ThreadSummary<SIZE>* thread_summary = process_summary->mutable_thread_summary(it->thread());
-                                                       thread_summary->add_io_time(t.length());
-
-                                                       //
-                                                       // Bytes completed
-                                                       //
-                                                       if (summary_timespan.contains(it->max() - AbsTime(1))) {
-                                                           summary.add_io_bytes_completed(it->size());
-                                                           process_summary->add_io_bytes_completed(it->size());
-                                                           thread_summary->add_io_bytes_completed(it->size());
-                                                       }
-                       }
-                       it++;
-                   }
-               }
-           }
-       }
-    }
-
-    //
-    // Calculate Jetsam activity data.
-    //
-    if (summary_cpu == NULL) {
-       // jetsam activity is stored in the MachineThread
-       for (MachineThread<SIZE>* machine_thread : _threads_by_time) {
-           const MachineProcess<SIZE>* process = &machine_thread->process();
-
-           ProcessSummary<SIZE>* process_summary = NULL;
-           ThreadSummary<SIZE>* thread_summary = NULL;
-
-           const auto& jetsam_activity = machine_thread->jetsam_activity();
-           if (!jetsam_activity.empty()) {
-               AbsInterval jetsam_timespan = AbsInterval(jetsam_activity.front().location(), jetsam_activity.back().max() - jetsam_activity.front().location());
-               AbsInterval trimmed_timespan = summary_timespan.intersection_range(jetsam_timespan);
-
-               if (trimmed_timespan.length() > 0) {
-                   auto start = interval_beginning_timespan(jetsam_activity, trimmed_timespan);
-                   auto end = interval_ending_timespan(jetsam_activity, trimmed_timespan);
-
-                   ASSERT(!start || start->intersects(trimmed_timespan), "Sanity");
-                   ASSERT(!end || end->intersects(trimmed_timespan), "Sanity");
-                   ASSERT((!start && !end) || ((start && end) && (start <= end)), "Sanity");
-
-                   if (start && end) {
-                       // NOTE! <=, not <,  because end is inclusive of data we want to count!
-                       while (start <= end) {
-                                                       //
-                                                       // NOTE! summary_timespan, NOT trimmed_timespan!
-                                                       //
-                                                       // 8/25/13 ... Okay, why do we care summary vs trimmed?
-                                                       // It shouldn't be possible for start to lie outside trimmed...
-                                                       // Leaving this for now rather than introducing some bizzare
-                                                       // corner case, but wth...
-                                                       //
-                                                       AbsInterval t = start->intersection_range(summary_timespan);
-
-                                                       ASSERT(t.length() > 0, "Might be too strong, but expecting this to be non-zero");
-
-                                                       summary.add_jetsam_time(t.length());
-
-                                                       // We must initialize these lazily. If we don't, every process and thread gets
-                                                       // a summary entry. But we don't want to keep looking them up over and over...
-                                                       if (!process_summary) {
-                                                           process_summary = summary.mutable_process_summary(process);
-                                                       }
-                                                       process_summary->add_jetsam_time(t.length());
-
-                                                       if (!thread_summary) {
-                                                           thread_summary = process_summary->mutable_thread_summary(machine_thread);
-                                                       }
-                                                       thread_summary->add_jetsam_time(t.length());
-
-                                                       start++;
-                       }
-                   }
-               }
-           }
-       }
-
-       // Jetsam kill times are stored in the process.
-       for (MachineProcess<SIZE>* machine_process : _processes_by_time) {
-           if (machine_process->is_exit_by_jetsam()) {
-               if (summary_timespan.contains(machine_process->exit_timestamp())) {
-                   summary.increment_processes_jetsamed();
-                   summary.mutable_process_summary(machine_process)->set_jetsam_killed();
-               }
-           }
-       }
-    }
-
-    DEBUG_ONLY(summary.validate());
-
-    return summary;
-}
-
-template <typename SIZE>
-uint32_t Machine<SIZE>::active_cpus() const {
-    uint32_t cpus = 0;
-
-    for (auto& cpu : _cpus) {
-       if (!cpu.timeline().empty()) {
-           cpus++;
-       }
-    }
-
-    return cpus;
-}
-
-// This attempts to analyze various pieces of data and guess
-// if the Machine represents an ios device or not.
-
-template <typename SIZE>
-bool Machine<SIZE>::is_ios() const {
-    // I looked at avg intr time, and min intr time; they were too close for
-    // reliable detection of desktop vs device (desktop has intr(s) as short
-    // as 60ns).
-    
-    // For now, we're just going to do a really gross detection, in any trace
-    // from a device we'd expect to see SpringBoard or backboardd.
-    
-    for (auto process : _processes_by_time) {
-       if (strcmp(process->name(), "SpringBoard") == 0)
-           return true;
-       if (strcmp(process->name(), "backboardd") == 0)
-           return true;
-    }
-    
-    return false;
-}