Decoder: Remove the thread context get/set from the decoder.

This interface is no longer used, and getting rid of it simplifies the
decoders and code that sets up the decoders. The thread context had been used
to read architectural state which was used to contextualize the instruction
memory as it came in. That was changed so that the state is now sent to the
decoders to keep locally if/when it changes. That's significantly more
efficient.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>

src/cpu/checker/cpu_impl.hh

@@ -306,7 +306,6 @@ Checker<Impl>::verify(DynInstPtr &completed_inst)
                     StaticInstPtr instPtr = NULL;
 
                     //Predecode, ie bundle up an ExtMachInst
-                    thread->decoder.setTC(thread->getTC());
                     //If more fetch data is needed, pass it in.
                     Addr fetchPC = (pcState.instAddr() & PCMask) + fetchOffset;
                     thread->decoder.moreBytes(pcState, fetchPC, machInst);

src/cpu/inorder/resources/fetch_unit.cc

@@ -59,7 +59,7 @@ FetchUnit::FetchUnit(string res_name, int res_id, int res_width,
       instSize(sizeof(TheISA::MachInst)), fetchBuffSize(params->fetchBuffSize)
 {
     for (int tid = 0; tid < MaxThreads; tid++)
-        decoder[tid] = new Decoder(NULL);
+        decoder[tid] = new Decoder;
 }
 
 FetchUnit::~FetchUnit()
@@ -109,7 +109,6 @@ FetchUnit::createMachInst(std::list<FetchBlock*>::iterator fetch_it,
     MachInst mach_inst =
         TheISA::gtoh(fetchInsts[fetch_offset]);
 
-    decoder[tid]->setTC(cpu->thread[tid]->getTC());
     decoder[tid]->moreBytes(instPC, inst->instAddr(), mach_inst);
     assert(decoder[tid]->instReady());
     inst->setStaticInst(decoder[tid]->decode(instPC));

src/cpu/legiontrace.cc

@@ -422,7 +422,6 @@ Trace::LegionTraceRecord::dump()
                          << endl;
 
                     TheISA::Decoder *decoder = thread->getDecoderPtr();
-                    decoder->setTC(thread);
                     decoder->moreBytes(m5Pc, m5Pc, shared_data->instruction);
 
                     assert(decoder->instReady());

src/cpu/o3/fetch_impl.hh

@@ -134,7 +134,7 @@ DefaultFetch<Impl>::DefaultFetch(O3CPU *_cpu, DerivO3CPUParams *params)
 
     for (int i = 0; i < Impl::MaxThreads; i++) {
         cacheData[i] = NULL;
-        decoder[i] = new TheISA::Decoder(NULL);
+        decoder[i] = new TheISA::Decoder;
     }
 }
 
@@ -1225,9 +1225,8 @@ DefaultFetch<Impl>::fetch(bool &status_change)
                 if (blkOffset >= numInsts)
                     break;
             }
-            MachInst inst = TheISA::gtoh(cacheInsts[blkOffset]);
 
-            decoder[tid]->setTC(cpu->thread[tid]->getTC());
+            MachInst inst = TheISA::gtoh(cacheInsts[blkOffset]);
             decoder[tid]->moreBytes(thisPC, fetchAddr, inst);
 
             if (decoder[tid]->needMoreBytes()) {

src/cpu/simple/base.cc

@@ -380,8 +380,6 @@ BaseSimpleCPU::preExecute()
         TheISA::Decoder *decoder = &(thread->decoder);
 
         //Predecode, ie bundle up an ExtMachInst
-        //This should go away once the constructor can be set up properly
-        decoder->setTC(thread->getTC());
         //If more fetch data is needed, pass it in.
         Addr fetchPC = (pcState.instAddr() & PCMask) + fetchOffset;
         //if(decoder->needMoreBytes())

src/cpu/simple_thread.cc

@@ -63,16 +63,16 @@ SimpleThread::SimpleThread(BaseCPU *_cpu, int _thread_num, System *_sys,
                            Process *_process, TheISA::TLB *_itb,
                            TheISA::TLB *_dtb)
     : ThreadState(_cpu, _thread_num, _process), system(_sys), itb(_itb),
-      dtb(_dtb), decoder(NULL)
+      dtb(_dtb)
 {
     clearArchRegs();
     tc = new ProxyThreadContext<SimpleThread>(this);
 }
+
 SimpleThread::SimpleThread(BaseCPU *_cpu, int _thread_num, System *_sys,
                            TheISA::TLB *_itb, TheISA::TLB *_dtb,
                            bool use_kernel_stats)
-    : ThreadState(_cpu, _thread_num, NULL), system(_sys), itb(_itb), dtb(_dtb),
-      decoder(NULL)
+    : ThreadState(_cpu, _thread_num, NULL), system(_sys), itb(_itb), dtb(_dtb)
 {
     tc = new ProxyThreadContext<SimpleThread>(this);
 
@@ -99,7 +99,7 @@ SimpleThread::SimpleThread(BaseCPU *_cpu, int _thread_num, System *_sys,
 }
 
 SimpleThread::SimpleThread()
-    : ThreadState(NULL, -1, NULL), decoder(NULL)
+    : ThreadState(NULL, -1, NULL)
 {
     tc = new ProxyThreadContext<SimpleThread>(this);
 }