base: Declare a type for context IDs

Context IDs used to be declared as ad hoc (usually as int). This
changeset introduces a typedef for ContextIDs and a constant for
invalid context IDs.

25 files changed, 65 insertions, 61 deletions

diff --git a/src/base/types.hh b/src/base/types.hh
index 3d53e6ba0..bc5c715ce 100644
--- a/src/base/types.hh
+++ b/src/base/types.hh
@@ -181,6 +181,10 @@ const Addr MaxAddr = (Addr)-1;
 typedef int16_t ThreadID;
 const ThreadID InvalidThreadID = (ThreadID)-1;
 
+/** Globally unique thread context ID */
+typedef int ContextID;
+const ContextID InvalidContextID = (ContextID)-1;
+
 /**
  * Port index/ID type, and a symbolic name for an invalid port id.
  */
diff --git a/src/cpu/base_dyn_inst.hh b/src/cpu/base_dyn_inst.hh
index 5b54679c9..aae3af495 100644
--- a/src/cpu/base_dyn_inst.hh
+++ b/src/cpu/base_dyn_inst.hh
@@ -460,7 +460,7 @@ class BaseDynInst : public ExecContext, public RefCounted
     MasterID masterId() const { return cpu->dataMasterId(); }
 
     /** Read this context's system-wide ID **/
-    int contextId() const { return thread->contextId(); }
+    ContextID contextId() const { return thread->contextId(); }
 
     /** Returns the fault type. */
     Fault getFault() const { return fault; }
diff --git a/src/cpu/checker/thread_context.hh b/src/cpu/checker/thread_context.hh
index 71c231ba0..5fcb82f6d 100644
--- a/src/cpu/checker/thread_context.hh
+++ b/src/cpu/checker/thread_context.hh
@@ -96,9 +96,9 @@ class CheckerThreadContext : public ThreadContext
 
     int cpuId() const { return actualTC->cpuId(); }
 
-    int contextId() const { return actualTC->contextId(); }
+    ContextID contextId() const { return actualTC->contextId(); }
 
-    void setContextId(int id)
+    void setContextId(ContextID id)
     {
        actualTC->setContextId(id);
        checkerTC->setContextId(id);
diff --git a/src/cpu/minor/exec_context.hh b/src/cpu/minor/exec_context.hh
index 80d5d9872..3e4ea5ea9 100644
--- a/src/cpu/minor/exec_context.hh
+++ b/src/cpu/minor/exec_context.hh
@@ -254,7 +254,7 @@ class ExecContext : public ::ExecContext
     unsigned int readStCondFailures() const { return 0; }
     void setStCondFailures(unsigned int st_cond_failures) {}
 
-    int contextId() { return thread.contextId(); }
+    ContextID contextId() { return thread.contextId(); }
     /* ISA-specific (or at least currently ISA singleton) functions */
 
     /* X86: TLB twiddling */
diff --git a/src/cpu/o3/thread_context.hh b/src/cpu/o3/thread_context.hh
index 87d87900c..87b7d9198 100755
--- a/src/cpu/o3/thread_context.hh
+++ b/src/cpu/o3/thread_context.hh
@@ -101,7 +101,7 @@ class O3ThreadContext : public ThreadContext
     /** Reads this CPU's Socket ID. */
     virtual uint32_t socketId() const { return cpu->socketId(); }
 
-    virtual int contextId() const { return thread->contextId(); }
+    virtual ContextID contextId() const { return thread->contextId(); }
 
     virtual void setContextId(int id) { thread->setContextId(id); }
 
diff --git a/src/cpu/thread_context.cc b/src/cpu/thread_context.cc
index fe1ae69dd..01ea51f26 100644
--- a/src/cpu/thread_context.cc
+++ b/src/cpu/thread_context.cc
@@ -95,9 +95,9 @@ ThreadContext::compare(ThreadContext *one, ThreadContext *two)
     if (id1 != id2)
         panic("CPU ids don't match, one: %d, two: %d", id1, id2);
 
-    id1 = one->contextId();
-    id2 = two->contextId();
-    if (id1 != id2)
+    const ContextID cid1 = one->contextId();
+    const ContextID cid2 = two->contextId();
+    if (cid1 != cid2)
         panic("Context ids don't match, one: %d, two: %d", id1, id2);
 
 
diff --git a/src/cpu/thread_state.hh b/src/cpu/thread_state.hh
index 485c9306f..bd471e13a 100644
--- a/src/cpu/thread_state.hh
+++ b/src/cpu/thread_state.hh
@@ -71,9 +71,9 @@ struct ThreadState : public Serializable {
 
     uint32_t socketId() const { return baseCpu->socketId(); }
 
-    int contextId() const { return _contextId; }
+    ContextID contextId() const { return _contextId; }
 
-    void setContextId(int id) { _contextId = id; }
+    void setContextId(ContextID id) { _contextId = id; }
 
     void setThreadId(ThreadID id) { _threadId = id; }
 
@@ -153,7 +153,7 @@ struct ThreadState : public Serializable {
     BaseCPU *baseCpu;
 
     // system wide HW context id
-    int _contextId;
+    ContextID _contextId;
 
     // Index of hardware thread context on the CPU that this represents.
     ThreadID _threadId;
diff --git a/src/dev/arm/gic_pl390.cc b/src/dev/arm/gic_pl390.cc
index 5a21f6cec..fb1711c92 100644
--- a/src/dev/arm/gic_pl390.cc
+++ b/src/dev/arm/gic_pl390.cc
@@ -135,7 +135,7 @@ Pl390::readDistributor(PacketPtr pkt)
 {
     Addr daddr = pkt->getAddr() - distAddr;
 
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
 
     DPRINTF(GIC, "gic distributor read register %#x\n", daddr);
 
@@ -269,7 +269,7 @@ Pl390::readCpu(PacketPtr pkt)
     Addr daddr = pkt->getAddr() - cpuAddr;
 
     assert(pkt->req->hasContextId());
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
     assert(ctx_id < sys->numRunningContexts());
 
     DPRINTF(GIC, "gic cpu read register %#x cpu context: %d\n", daddr,
@@ -356,7 +356,7 @@ Pl390::writeDistributor(PacketPtr pkt)
     Addr daddr = pkt->getAddr() - distAddr;
 
     assert(pkt->req->hasContextId());
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
 
     uint32_t pkt_data M5_VAR_USED;
     switch (pkt->getSize())
@@ -496,7 +496,7 @@ Pl390::writeCpu(PacketPtr pkt)
     Addr daddr = pkt->getAddr() - cpuAddr;
 
     assert(pkt->req->hasContextId());
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
     IAR iar;
 
     DPRINTF(GIC, "gic cpu write register cpu:%d %#x val: %#x\n",
@@ -546,7 +546,7 @@ Pl390::writeCpu(PacketPtr pkt)
 }
 
 void
-Pl390::softInt(int ctx_id, SWI swi)
+Pl390::softInt(ContextID ctx_id, SWI swi)
 {
     switch (swi.list_type) {
       case 1:
diff --git a/src/dev/arm/gic_pl390.hh b/src/dev/arm/gic_pl390.hh
index 1adad6c9a..17946145f 100644
--- a/src/dev/arm/gic_pl390.hh
+++ b/src/dev/arm/gic_pl390.hh
@@ -210,7 +210,7 @@ class Pl390 : public BaseGic
     /** software generated interrupt
      * @param data data to decode that indicates which cpus to interrupt
      */
-    void softInt(int ctx_id, SWI swi);
+    void softInt(ContextID ctx_id, SWI swi);
 
     /** See if some processor interrupt flags need to be enabled/disabled
      * @param hint which set of interrupts needs to be checked
diff --git a/src/dev/arm/timer_cpulocal.cc b/src/dev/arm/timer_cpulocal.cc
index ac02d099f..11ae3b3d2 100644
--- a/src/dev/arm/timer_cpulocal.cc
+++ b/src/dev/arm/timer_cpulocal.cc
@@ -75,7 +75,7 @@ CpuLocalTimer::read(PacketPtr pkt)
     assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
     assert(pkt->getSize() == 4);
     Addr daddr = pkt->getAddr() - pioAddr;
-    int cpu_id = pkt->req->contextId();
+    ContextID cpu_id = pkt->req->contextId();
     DPRINTF(Timer, "Reading from CpuLocalTimer at offset: %#x\n", daddr);
     assert(cpu_id >= 0);
     assert(cpu_id < CPU_MAX);
@@ -153,7 +153,7 @@ CpuLocalTimer::write(PacketPtr pkt)
     assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
     assert(pkt->getSize() == 4);
     Addr daddr = pkt->getAddr() - pioAddr;
-    int cpu_id = pkt->req->contextId();
+    ContextID cpu_id = pkt->req->contextId();
     DPRINTF(Timer, "Writing to CpuLocalTimer at offset: %#x\n", daddr);
     assert(cpu_id >= 0);
     assert(cpu_id < CPU_MAX);
diff --git a/src/dev/arm/vgic.cc b/src/dev/arm/vgic.cc
index f4a3e8c3f..71d1d3bb6 100644
--- a/src/dev/arm/vgic.cc
+++ b/src/dev/arm/vgic.cc
@@ -90,7 +90,7 @@ VGic::readVCpu(PacketPtr pkt)
 {
     Addr daddr = pkt->getAddr() - vcpuAddr;
 
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
     assert(ctx_id < VGIC_CPU_MAX);
     struct vcpuIntData *vid = &vcpuData[ctx_id];
 
@@ -134,7 +134,7 @@ VGic::readCtrl(PacketPtr pkt)
 {
     Addr daddr = pkt->getAddr() - hvAddr;
 
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
 
     DPRINTF(VGIC, "VGIC HVCtrl read register %#x\n", daddr);
 
@@ -228,7 +228,7 @@ VGic::writeVCpu(PacketPtr pkt)
 {
     Addr daddr = pkt->getAddr() - vcpuAddr;
 
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
     assert(ctx_id < VGIC_CPU_MAX);
     struct vcpuIntData *vid = &vcpuData[ctx_id];
 
@@ -275,7 +275,7 @@ VGic::writeCtrl(PacketPtr pkt)
 {
     Addr daddr = pkt->getAddr() - hvAddr;
 
-    int ctx_id = pkt->req->contextId();
+    ContextID ctx_id = pkt->req->contextId();
 
     DPRINTF(VGIC, "VGIC HVCtrl write register %#x <= %#x\n", daddr, pkt->get<uint32_t>());
 
@@ -380,7 +380,7 @@ VGic::unPostMaintInt(uint32_t cpu)
  * This may raise a maintenance interrupt.
  */
 void
-VGic::updateIntState(int ctx_id)
+VGic::updateIntState(ContextID ctx_id)
 {
     // @todo This should update APRs!
 
diff --git a/src/dev/arm/vgic.hh b/src/dev/arm/vgic.hh
index ac88f842f..d44afd7a9 100644
--- a/src/dev/arm/vgic.hh
+++ b/src/dev/arm/vgic.hh
@@ -222,7 +222,7 @@ class VGic : public PioDevice
     Tick writeVCpu(PacketPtr pkt);
     Tick writeCtrl(PacketPtr pkt);
 
-    void updateIntState(int ctx_id);
+    void updateIntState(ContextID ctx_id);
     uint32_t getMISR(struct vcpuIntData *vid);
     void postVInt(uint32_t cpu, Tick when);
     void unPostVInt(uint32_t cpu);
diff --git a/src/dev/sinic.cc b/src/dev/sinic.cc
index d4a3f19b3..a17f50864 100644
--- a/src/dev/sinic.cc
+++ b/src/dev/sinic.cc
@@ -152,7 +152,7 @@ Device::getEthPort(const std::string &if_name, int idx)
 
 
 void
-Device::prepareIO(int cpu, int index)
+Device::prepareIO(ContextID cpu, int index)
 {
     int size = virtualRegs.size();
     if (index > size)
@@ -165,7 +165,7 @@ Device::prepareIO(int cpu, int index)
 //add stats for average number of vnics busy
 
 void
-Device::prepareRead(int cpu, int index)
+Device::prepareRead(ContextID cpu, int index)
 {
     using namespace Regs;
     prepareIO(cpu, index);
@@ -206,7 +206,7 @@ Device::prepareRead(int cpu, int index)
 }
 
 void
-Device::prepareWrite(int cpu, int index)
+Device::prepareWrite(ContextID cpu, int index)
 {
     prepareIO(cpu, index);
 }
@@ -220,7 +220,7 @@ Device::read(PacketPtr pkt)
     assert(config.command & PCI_CMD_MSE);
     assert(pkt->getAddr() >= BARAddrs[0] && pkt->getSize() < BARSize[0]);
 
-    int cpu = pkt->req->contextId();
+    ContextID cpu = pkt->req->contextId();
     Addr daddr = pkt->getAddr() - BARAddrs[0];
     Addr index = daddr >> Regs::VirtualShift;
     Addr raddr = daddr & Regs::VirtualMask;
@@ -270,7 +270,7 @@ Device::read(PacketPtr pkt)
  * IPR read of device register
 
     Fault
-Device::iprRead(Addr daddr, int cpu, uint64_t &result)
+Device::iprRead(Addr daddr, ContextID cpu, uint64_t &result)
 {
     if (!regValid(daddr))
         panic("invalid address: da=%#x", daddr);
@@ -305,7 +305,7 @@ Device::write(PacketPtr pkt)
     assert(config.command & PCI_CMD_MSE);
     assert(pkt->getAddr() >= BARAddrs[0] && pkt->getSize() < BARSize[0]);
 
-    int cpu = pkt->req->contextId();
+    ContextID cpu = pkt->req->contextId();
     Addr daddr = pkt->getAddr() - BARAddrs[0];
     Addr index = daddr >> Regs::VirtualShift;
     Addr raddr = daddr & Regs::VirtualMask;
diff --git a/src/dev/sinic.hh b/src/dev/sinic.hh
index 69b81b1b2..f0645a807 100644
--- a/src/dev/sinic.hh
+++ b/src/dev/sinic.hh
@@ -273,10 +273,10 @@ class Device : public Base
     virtual Tick write(PacketPtr pkt);
     virtual void drainResume() M5_ATTR_OVERRIDE;
 
-    void prepareIO(int cpu, int index);
-    void prepareRead(int cpu, int index);
-    void prepareWrite(int cpu, int index);
- //   Fault iprRead(Addr daddr, int cpu, uint64_t &result);
+    void prepareIO(ContextID cpu, int index);
+    void prepareRead(ContextID cpu, int index);
+    void prepareWrite(ContextID cpu, int index);
+ //   Fault iprRead(Addr daddr, ContextID cpu, uint64_t &result);
 
 /**
  * Statistics
diff --git a/src/dev/sparc/iob.cc b/src/dev/sparc/iob.cc
index bee0323c8..c8462b9be 100644
--- a/src/dev/sparc/iob.cc
+++ b/src/dev/sparc/iob.cc
@@ -118,7 +118,7 @@ void
 Iob::readJBus(PacketPtr pkt)
 {
         Addr accessAddr = pkt->getAddr() - iobJBusAddr;
-        int cpuid = pkt->req->contextId();
+        ContextID cpuid = pkt->req->contextId();
         int index;
         uint64_t data;
 
@@ -233,7 +233,7 @@ void
 Iob::writeJBus(PacketPtr pkt)
 {
         Addr accessAddr = pkt->getAddr() - iobJBusAddr;
-        int cpuid = pkt->req->contextId();
+        ContextID cpuid = pkt->req->contextId();
         int index;
         uint64_t data;
 
diff --git a/src/mem/abstract_mem.hh b/src/mem/abstract_mem.hh
index 4b7ad8139..6dbc79ea0 100644
--- a/src/mem/abstract_mem.hh
+++ b/src/mem/abstract_mem.hh
@@ -74,7 +74,7 @@ class LockedAddr {
     Addr addr;
 
     // locking hw context
-    const int contextId;
+    const ContextID contextId;
 
     static Addr mask(Addr paddr) { return (paddr & ~Addr_Mask); }
 
diff --git a/src/mem/cache/blk.hh b/src/mem/cache/blk.hh
index 0be22f45d..2b3a34bb8 100644
--- a/src/mem/cache/blk.hh
+++ b/src/mem/cache/blk.hh
@@ -130,7 +130,7 @@ class CacheBlk
      */
     class Lock {
       public:
-        int contextId;     // locking context
+        ContextID contextId;     // locking context
         Addr lowAddr;      // low address of lock range
         Addr highAddr;     // high address of lock range
 
diff --git a/src/mem/cache/cache_impl.hh b/src/mem/cache/cache_impl.hh
index 62ab49538..dea95d955 100644
--- a/src/mem/cache/cache_impl.hh
+++ b/src/mem/cache/cache_impl.hh
@@ -332,7 +332,8 @@ Cache::access(PacketPtr pkt, CacheBlk *&blk, Cycles &lat,
         return false;
     }
 
-    int id = pkt->req->hasContextId() ? pkt->req->contextId() : -1;
+    ContextID id = pkt->req->hasContextId() ?
+        pkt->req->contextId() : InvalidContextID;
     // Here lat is the value passed as parameter to accessBlock() function
     // that can modify its value.
     blk = tags->accessBlock(pkt->getAddr(), pkt->isSecure(), lat, id);
diff --git a/src/mem/physical.cc b/src/mem/physical.cc
index d757b8c5d..dfea2e9e1 100644
--- a/src/mem/physical.cc
+++ b/src/mem/physical.cc
@@ -293,7 +293,7 @@ PhysicalMemory::serialize(CheckpointOut &cp) const
 {
     // serialize all the locked addresses and their context ids
     vector<Addr> lal_addr;
-    vector<int> lal_cid;
+    vector<ContextID> lal_cid;
 
     for (auto& m : memories) {
         const list<LockedAddr>& locked_addrs = m->getLockedAddrList();
@@ -370,7 +370,7 @@ PhysicalMemory::unserialize(CheckpointIn &cp)
     // unserialize the locked addresses and map them to the
     // appropriate memory controller
     vector<Addr> lal_addr;
-    vector<int> lal_cid;
+    vector<ContextID> lal_cid;
     UNSERIALIZE_CONTAINER(lal_addr);
     UNSERIALIZE_CONTAINER(lal_cid);
     for(size_t i = 0; i < lal_addr.size(); ++i) {
diff --git a/src/mem/request.hh b/src/mem/request.hh
index 192b4c89f..0e2ece857 100644
--- a/src/mem/request.hh
+++ b/src/mem/request.hh
@@ -296,7 +296,7 @@ class Request
     uint64_t _extraData;
 
     /** The context ID (for statistics, typically). */
-    int _contextId;
+    ContextID _contextId;
     /** The thread ID (id within this CPU) */
     ThreadID _threadId;
 
@@ -353,7 +353,7 @@ class Request
     }
 
     Request(int asid, Addr vaddr, unsigned size, Flags flags, MasterID mid,
-            Addr pc, int cid, ThreadID tid)
+            Addr pc, ContextID cid, ThreadID tid)
         : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
           _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
           _extraData(0), _contextId(0), _threadId(0), _pc(0),
@@ -369,7 +369,7 @@ class Request
      * Set up CPU and thread numbers.
      */
     void
-    setThreadContext(int context_id, ThreadID tid)
+    setThreadContext(ContextID context_id, ThreadID tid)
     {
         _contextId = context_id;
         _threadId = tid;
@@ -591,7 +591,7 @@ class Request
     }
 
     /** Accessor function for context ID.*/
-    int
+    ContextID
     contextId() const
     {
         assert(privateFlags.isSet(VALID_CONTEXT_ID));
diff --git a/src/mem/ruby/slicc_interface/RubyRequest.hh b/src/mem/ruby/slicc_interface/RubyRequest.hh
index 357eddbb5..cdb04bceb 100644
--- a/src/mem/ruby/slicc_interface/RubyRequest.hh
+++ b/src/mem/ruby/slicc_interface/RubyRequest.hh
@@ -49,12 +49,12 @@ class RubyRequest : public Message
     PrefetchBit m_Prefetch;
     uint8_t* data;
     PacketPtr pkt;
-    unsigned m_contextId;
+    ContextID m_contextId;
 
     RubyRequest(Tick curTime, uint64_t _paddr, uint8_t* _data, int _len,
         uint64_t _pc, RubyRequestType _type, RubyAccessMode _access_mode,
         PacketPtr _pkt, PrefetchBit _pb = PrefetchBit_No,
-        unsigned _proc_id = 100)
+        ContextID _proc_id = 100)
         : Message(curTime),
           m_PhysicalAddress(_paddr),
           m_Type(_type),
diff --git a/src/mem/ruby/system/Sequencer.cc b/src/mem/ruby/system/Sequencer.cc
index 32e4c107c..01b868017 100644
--- a/src/mem/ruby/system/Sequencer.cc
+++ b/src/mem/ruby/system/Sequencer.cc
@@ -667,10 +667,8 @@ void
 Sequencer::issueRequest(PacketPtr pkt, RubyRequestType secondary_type)
 {
     assert(pkt != NULL);
-    int proc_id = -1;
-    if (pkt->req->hasContextId()) {
-        proc_id = pkt->req->contextId();
-    }
+    ContextID proc_id = pkt->req->hasContextId() ?
+        pkt->req->contextId() : InvalidContextID;
 
     // If valid, copy the pc to the ruby request
     Addr pc = 0;
diff --git a/src/sim/process.hh b/src/sim/process.hh
index 82a84a935..f509b81c7 100644
--- a/src/sim/process.hh
+++ b/src/sim/process.hh
@@ -75,7 +75,7 @@ class Process : public SimObject
     System *system;
 
     // thread contexts associated with this process
-    std::vector<int> contextIds;
+    std::vector<ContextID> contextIds;
 
     // number of CPUs (esxec contexts, really) assigned to this process.
     unsigned int numCpus() { return contextIds.size(); }
@@ -160,7 +160,7 @@ class Process : public SimObject
 
     // After getting registered with system object, tell process which
     // system-wide context id it is assigned.
-    void assignThreadContext(int context_id)
+    void assignThreadContext(ContextID context_id)
     {
         contextIds.push_back(context_id);
     }
diff --git a/src/sim/system.cc b/src/sim/system.cc
index c5e2e0b96..d0418d99b 100644
--- a/src/sim/system.cc
+++ b/src/sim/system.cc
@@ -209,11 +209,11 @@ bool System::breakpoint()
  */
 int rgdb_wait = -1;
 
-int
-System::registerThreadContext(ThreadContext *tc, int assigned)
+ContextID
+System::registerThreadContext(ThreadContext *tc, ContextID assigned)
 {
     int id;
-    if (assigned == -1) {
+    if (assigned == InvalidContextID) {
         for (id = 0; id < threadContexts.size(); id++) {
             if (!threadContexts[id])
                 break;
@@ -305,7 +305,7 @@ System::initState()
 }
 
 void
-System::replaceThreadContext(ThreadContext *tc, int context_id)
+System::replaceThreadContext(ThreadContext *tc, ContextID context_id)
 {
     if (context_id >= threadContexts.size()) {
         panic("replaceThreadContext: bad id, %d >= %d\n",
diff --git a/src/sim/system.hh b/src/sim/system.hh
index 97d271d3a..634c78a6a 100644
--- a/src/sim/system.hh
+++ b/src/sim/system.hh
@@ -197,7 +197,7 @@ class System : public MemObject
     std::vector<ThreadContext *> threadContexts;
     int _numContexts;
 
-    ThreadContext *getThreadContext(ThreadID tid)
+    ThreadContext *getThreadContext(ContextID tid)
     {
         return threadContexts[tid];
     }
@@ -514,8 +514,9 @@ class System : public MemObject
     /// @return Starting address of first page
     Addr allocPhysPages(int npages);
 
-    int registerThreadContext(ThreadContext *tc, int assigned=-1);
-    void replaceThreadContext(ThreadContext *tc, int context_id);
+    ContextID registerThreadContext(ThreadContext *tc,
+                                    ContextID assigned = InvalidContextID);
+    void replaceThreadContext(ThreadContext *tc, ContextID context_id);
 
     void serialize(CheckpointOut &cp) const M5_ATTR_OVERRIDE;
     void unserialize(CheckpointIn &cp) M5_ATTR_OVERRIDE;