From a2b56088fb4d12aee73ecfeaba88cfa46f98567e Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Thu, 15 Mar 2007 02:47:42 +0000 Subject: Make the predecoder an object with it's own switched header file. Start adding predecoding functionality to x86. src/arch/SConscript: src/arch/alpha/utility.hh: src/arch/mips/utility.hh: src/arch/sparc/utility.hh: src/cpu/base.hh: src/cpu/o3/fetch.hh: src/cpu/o3/fetch_impl.hh: src/cpu/simple/atomic.cc: src/cpu/simple/base.cc: src/cpu/simple/base.hh: src/cpu/static_inst.hh: src/arch/alpha/predecoder.hh: src/arch/mips/predecoder.hh: src/arch/sparc/predecoder.hh: Make the predecoder an object with it's own switched header file. --HG-- extra : convert_revision : 77206e29089130e86b97164c30022a062699ba86 --- src/cpu/simple/atomic.cc | 32 ++++++++++++++++++++++---------- src/cpu/simple/base.cc | 23 ++++++++++++----------- src/cpu/simple/base.hh | 9 +++++++-- 3 files changed, 41 insertions(+), 23 deletions(-) (limited to 'src/cpu/simple') diff --git a/src/cpu/simple/atomic.cc b/src/cpu/simple/atomic.cc index df7e780e6..0361db012 100644 --- a/src/cpu/simple/atomic.cc +++ b/src/cpu/simple/atomic.cc @@ -500,17 +500,28 @@ AtomicSimpleCPU::tick() Fault fault = setupFetchRequest(ifetch_req); if (fault == NoFault) { - ifetch_pkt->reinitFromRequest(); + Tick icache_latency = 0; + bool icache_access = false; + dcache_access = false; // assume no dcache access - Tick icache_latency = icachePort.sendAtomic(ifetch_pkt); - // ifetch_req is initialized to read the instruction directly - // into the CPU object's inst field. + //Fetch more instruction memory if necessary + if(predecoder.needMoreBytes()) + { + icache_access = true; + ifetch_pkt->reinitFromRequest(); + + icache_latency = icachePort.sendAtomic(ifetch_pkt); + // ifetch_req is initialized to read the instruction directly + // into the CPU object's inst field. + } - dcache_access = false; // assume no dcache access preExecute(); - fault = curStaticInst->execute(this, traceData); - postExecute(); + if(curStaticInst) + { + fault = curStaticInst->execute(this, traceData); + postExecute(); + } // @todo remove me after debugging with legion done if (curStaticInst && (!curStaticInst->isMicroOp() || @@ -518,7 +529,8 @@ AtomicSimpleCPU::tick() instCnt++; if (simulate_stalls) { - Tick icache_stall = icache_latency - cycles(1); + Tick icache_stall = + icache_access ? icache_latency - cycles(1) : 0; Tick dcache_stall = dcache_access ? dcache_latency - cycles(1) : 0; Tick stall_cycles = (icache_stall + dcache_stall) / cycles(1); @@ -529,8 +541,8 @@ AtomicSimpleCPU::tick() } } - - advancePC(fault); + if(predecoder.needMoreBytes()) + advancePC(fault); } if (_status != Idle) diff --git a/src/cpu/simple/base.cc b/src/cpu/simple/base.cc index c27be02bf..2ad328542 100644 --- a/src/cpu/simple/base.cc +++ b/src/cpu/simple/base.cc @@ -70,7 +70,7 @@ using namespace std; using namespace TheISA; BaseSimpleCPU::BaseSimpleCPU(Params *p) - : BaseCPU(p), thread(NULL) + : BaseCPU(p), thread(NULL), predecoder(NULL) { #if FULL_SYSTEM thread = new SimpleThread(this, 0, p->system, p->itb, p->dtb); @@ -370,11 +370,16 @@ BaseSimpleCPU::preExecute() StaticInstPtr instPtr = NULL; //Predecode, ie bundle up an ExtMachInst - unsigned int result = - predecode(extMachInst, thread->readPC(), inst, thread->getTC()); + //This should go away once the constructor can be set up properly + predecoder.setTC(thread->getTC()); + //If more fetch data is needed, pass it in. + if(predecoder.needMoreBytes()) + predecoder.moreBytes(thread->readPC(), 0, inst); + else + predecoder.process(); //If an instruction is ready, decode it - if (result & ExtMIReady) - instPtr = StaticInst::decode(extMachInst); + if (predecoder.extMachInstReady()) + instPtr = StaticInst::decode(predecoder.getExtMachInst()); //If we decoded an instruction and it's microcoded, start pulling //out micro ops @@ -446,9 +451,9 @@ BaseSimpleCPU::advancePC(Fault fault) fault->invoke(tc); thread->setMicroPC(0); thread->setNextMicroPC(1); - } else { + } else if (predecoder.needMoreBytes()) { //If we're at the last micro op for this instruction - if (curStaticInst->isLastMicroOp()) { + if (curStaticInst && curStaticInst->isLastMicroOp()) { //We should be working with a macro op assert(curMacroStaticInst); //Close out this macro op, and clean up the @@ -467,13 +472,9 @@ BaseSimpleCPU::advancePC(Fault fault) } else { // go to the next instruction thread->setPC(thread->readNextPC()); -#if ISA_HAS_DELAY_SLOT thread->setNextPC(thread->readNextNPC()); thread->setNextNPC(thread->readNextNPC() + sizeof(MachInst)); assert(thread->readNextPC() != thread->readNextNPC()); -#else - thread->setNextPC(thread->readNextPC() + sizeof(MachInst)); -#endif } } diff --git a/src/cpu/simple/base.hh b/src/cpu/simple/base.hh index 10787c474..a7686bbb1 100644 --- a/src/cpu/simple/base.hh +++ b/src/cpu/simple/base.hh @@ -33,6 +33,7 @@ #ifndef __CPU_SIMPLE_BASE_HH__ #define __CPU_SIMPLE_BASE_HH__ +#include "arch/predecoder.hh" #include "base/statistics.hh" #include "config/full_system.hh" #include "cpu/base.hh" @@ -63,6 +64,10 @@ class Process; class RemoteGDB; class GDBListener; +namespace TheISA +{ + class Predecoder; +} class ThreadContext; class Checkpoint; @@ -123,8 +128,8 @@ class BaseSimpleCPU : public BaseCPU // current instruction TheISA::MachInst inst; - // current extended machine instruction - TheISA::ExtMachInst extMachInst; + // The predecoder + TheISA::Predecoder predecoder; // Static data storage TheISA::LargestRead dataReg; -- cgit v1.2.3