cpu: Make CPU and ThreadContext getters const

This patch merely tidies up the CPU and ThreadContext getters by
making them const where appropriate.

src/cpu/base.hh

@@ -143,7 +143,7 @@ class BaseCPU : public MemObject
     virtual MasterPort &getInstPort() = 0;
 
     /** Reads this CPU's ID. */
-    int cpuId() { return _cpuId; }
+    int cpuId() const { return _cpuId; }
 
     /** Reads this CPU's unique data requestor ID */
     MasterID dataMasterId() { return _dataMasterId; }

src/cpu/base_dyn_inst.hh

@@ -454,16 +454,16 @@ class BaseDynInst : public RefCounted
     void dump(std::string &outstring);
 
     /** Read this CPU's ID. */
-    int cpuId() { return cpu->cpuId(); }
+    int cpuId() const { return cpu->cpuId(); }
 
     /** Read this CPU's data requestor ID */
-    MasterID masterId() { return cpu->dataMasterId(); }
+    MasterID masterId() const { return cpu->dataMasterId(); }
 
     /** Read this context's system-wide ID **/
-    int contextId() { return thread->contextId(); }
+    int contextId() const { return thread->contextId(); }
 
     /** Returns the fault type. */
-    Fault getFault() { return fault; }
+    Fault getFault() const { return fault; }
 
     /** Checks whether or not this instruction has had its branch target
      *  calculated yet.  For now it is not utilized and is hacked to be

src/cpu/checker/thread_context.hh

@@ -92,9 +92,9 @@ class CheckerThreadContext : public ThreadContext
 
     BaseCPU *getCpuPtr() { return actualTC->getCpuPtr(); }
 
-    int cpuId() { return actualTC->cpuId(); }
+    int cpuId() const { return actualTC->cpuId(); }
 
-    int contextId() { return actualTC->contextId(); }
+    int contextId() const { return actualTC->contextId(); }
 
     void setContextId(int id)
     {
@@ -103,7 +103,7 @@ class CheckerThreadContext : public ThreadContext
     }
 
     /** Returns this thread's ID number. */
-    int threadId() { return actualTC->threadId(); }
+    int threadId() const { return actualTC->threadId(); }
     void setThreadId(int id)
     {
         checkerTC->setThreadId(id);

src/cpu/inorder/inorder_dyn_inst.cc

@@ -91,7 +91,7 @@ InOrderDynInst::InOrderDynInst(InOrderCPU *cpu,
 int InOrderDynInst::instcount = 0;
 
 int
-InOrderDynInst::cpuId()
+InOrderDynInst::cpuId() const
 {
     return cpu->cpuId();
 }

src/cpu/inorder/inorder_dyn_inst.hh

@@ -357,10 +357,10 @@ class InOrderDynInst : public RefCounted
     Fault getFault() { return fault; }
 
     /** Read this CPU's ID. */
-    int cpuId();
+    int cpuId() const;
 
     /** Read this context's system-wide ID **/
-    int contextId() { return thread->contextId(); }
+    int contextId() const { return thread->contextId(); }
 
     ////////////////////////////////////////////////////////////
     //

src/cpu/inorder/thread_context.hh

@@ -111,14 +111,14 @@ class InOrderThreadContext : public ThreadContext
     std::string getCpuName() { return cpu->name(); }
 
     /** Reads this CPU's ID. */
-    int cpuId() { return cpu->cpuId(); }
+    int cpuId() const { return cpu->cpuId(); }
 
-    int contextId() { return thread->contextId(); }
+    int contextId() const { return thread->contextId(); }
 
     void setContextId(int id) { thread->setContextId(id); }
 
     /** Returns this thread's ID number. */
-    int threadId() { return thread->threadId(); }
+    int threadId() const { return thread->threadId(); }
     void setThreadId(int id) { return thread->setThreadId(id); }
 
     uint64_t readMicroPC()

src/cpu/o3/thread_context.hh

@@ -96,14 +96,14 @@ class O3ThreadContext : public ThreadContext
     virtual BaseCPU *getCpuPtr() { return cpu; }
 
     /** Reads this CPU's ID. */
-    virtual int cpuId() { return cpu->cpuId(); }
+    virtual int cpuId() const { return cpu->cpuId(); }
 
-    virtual int contextId() { return thread->contextId(); }
+    virtual int contextId() const { return thread->contextId(); }
 
     virtual void setContextId(int id) { thread->setContextId(id); }
 
     /** Returns this thread's ID number. */
-    virtual int threadId() { return thread->threadId(); }
+    virtual int threadId() const { return thread->threadId(); }
     virtual void setThreadId(int id) { return thread->setThreadId(id); }
 
     /** Returns a pointer to the system. */

src/cpu/ozone/cpu.hh

@@ -149,7 +149,7 @@ class OzoneCPU : public BaseCPU
         void profileClear();
         void profileSample();
 
-        int threadId();
+        int threadId() const;
 
         void copyArchRegs(ThreadContext *tc);
 

src/cpu/ozone/cpu_impl.hh

@@ -704,7 +704,7 @@ OzoneCPU<Impl>::OzoneTC::profileSample()
 
 template <class Impl>
 int
-OzoneCPU<Impl>::OzoneTC::threadId()
+OzoneCPU<Impl>::OzoneTC::threadId() const
 {
     return thread->threadId();
 }

src/cpu/thread_context.hh

@@ -121,13 +121,13 @@ class ThreadContext
 
     virtual BaseCPU *getCpuPtr() = 0;
 
-    virtual int cpuId() = 0;
+    virtual int cpuId() const = 0;
 
-    virtual int threadId() = 0;
+    virtual int threadId() const = 0;
 
     virtual void setThreadId(int id) = 0;
 
-    virtual int contextId() = 0;
+    virtual int contextId() const = 0;
 
     virtual void setContextId(int id) = 0;
 
@@ -321,13 +321,13 @@ class ProxyThreadContext : public ThreadContext
 
     BaseCPU *getCpuPtr() { return actualTC->getCpuPtr(); }
 
-    int cpuId() { return actualTC->cpuId(); }
+    int cpuId() const { return actualTC->cpuId(); }
 
-    int threadId() { return actualTC->threadId(); }
+    int threadId() const { return actualTC->threadId(); }
 
-    void setThreadId(int id) { return actualTC->setThreadId(id); }
+    void setThreadId(int id) { actualTC->setThreadId(id); }
 
-    int contextId() { return actualTC->contextId(); }
+    int contextId() const { return actualTC->contextId(); }
 
     void setContextId(int id) { actualTC->setContextId(id); }
 

src/cpu/thread_state.hh

@@ -67,19 +67,19 @@ struct ThreadState {
 
     void unserialize(Checkpoint *cp, const std::string &section);
 
-    int cpuId() { return baseCpu->cpuId(); }
+    int cpuId() const { return baseCpu->cpuId(); }
 
-    int contextId() { return _contextId; }
+    int contextId() const { return _contextId; }
 
     void setContextId(int id) { _contextId = id; }
 
     void setThreadId(ThreadID id) { _threadId = id; }
 
-    ThreadID threadId() { return _threadId; }
+    ThreadID threadId() const { return _threadId; }
 
-    Tick readLastActivate() { return lastActivate; }
+    Tick readLastActivate() const { return lastActivate; }
 
-    Tick readLastSuspend() { return lastSuspend; }
+    Tick readLastSuspend() const { return lastSuspend; }
 
     /**
      * Initialise the physical and virtual port proxies and tie them to