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inorder: stage width as a python parameter

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allow the user to specify how many instructions a pipeline stage can process
on any given cycle (stageWidth...i.e.bandwidth) by setting the parameter through
the python interface rather than compile the code after changing the *.cc file.
(we always had the parameter there, but still used the static 'ThePipeline::StageWidth'
instead)
-
Since StageWidth is now dynamically defined, change the interstage communication
structure to use a vector and get rid of array and array handling index (toNextStageIndex)
since we can just make calls to the list for the same information
This commit is contained in:
Korey Sewell 2011-02-04 00:08:18 -05:00
parent 8ac717ef4c
commit 0c6a679359
7 changed files with 35 additions and 67 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
src/cpu/inorder/InOrderCPU.py
View file

@ -40,7 +40,7 @@ class InOrderCPU(BaseCPU):
threadModel = Param.ThreadModel('SMT', "Multithreading model (SE-MODE only)")
cachePorts = Param.Unsigned(2, "Cache Ports")
stageWidth = Param.Unsigned(1, "Stage width")
stageWidth = Param.Unsigned(4, "Stage width")
fetchMemPort = Param.String("icache_port" , "Name of Memory Port to get instructions from")
dataMemPort = Param.String("dcache_port" , "Name of Memory Port to get data from")

11
src/cpu/inorder/comm.hh
View file

@ -44,8 +44,7 @@
/** Struct that defines the information passed from in between stages */
/** This information mainly goes forward through the pipeline. */
struct InterStageStruct {
int size;
ThePipeline::DynInstPtr insts[ThePipeline::StageWidth];
std::vector<ThePipeline::DynInstPtr> insts;
bool squash;
bool branchMispredict;
bool branchTaken;
@ -55,10 +54,10 @@ struct InterStageStruct {
bool includeSquashInst;
InterStageStruct()
:size(0), squash(false),
branchMispredict(false), branchTaken(false),
mispredPC(0), nextPC(0),
squashedSeqNum(0), includeSquashInst(false)
: squash(false),
branchMispredict(false), branchTaken(false),
mispredPC(0), nextPC(0),
squashedSeqNum(0), includeSquashInst(false)
{ }
};

1
src/cpu/inorder/cpu.cc
View file

@ -174,6 +174,7 @@ InOrderCPU::InOrderCPU(Params *params)
coreType("default"),
_status(Idle),
tickEvent(this),
stageWidth(params->stageWidth),
timeBuffer(2 , 2),
removeInstsThisCycle(false),
activityRec(params->name, NumStages, 10, params->activity),

3
src/cpu/inorder/cpu.hh
View file

@ -268,6 +268,9 @@ class InOrderCPU : public BaseCPU
/** The Pipeline Stages for the CPU */
PipelineStage *pipelineStage[ThePipeline::NumStages];
/** Width (processing bandwidth) of each stage */
int stageWidth;
/** Program Counters */
TheISA::PCState pc[ThePipeline::MaxThreads];

51
src/cpu/inorder/pipeline_stage.cc
View file

@ -39,9 +39,9 @@ using namespace std;
using namespace ThePipeline;
PipelineStage::PipelineStage(Params *params, unsigned stage_num)
: stageNum(stage_num), stageWidth(ThePipeline::StageWidth),
: stageNum(stage_num), stageWidth(params->stageWidth),
numThreads(ThePipeline::MaxThreads), _status(Inactive),
stageBufferMax(ThePipeline::interStageBuffSize[stage_num]),
stageBufferMax(params->stageWidth),
prevStageValid(false), nextStageValid(false), idle(false)
{
switchedOutBuffer.resize(ThePipeline::MaxThreads);
@ -143,7 +143,6 @@ PipelineStage::setNextStageQueue(TimeBuffer<InterStageStruct> *next_stage_ptr)
// Setup wire to write information to proper place in stage queue.
nextStage = nextStageQueue->getWire(0);
nextStage->size = 0;
nextStageValid = true;
}
@ -257,7 +256,7 @@ PipelineStage::removeStalls(ThreadID tid)
inline bool
PipelineStage::prevStageInstsValid()
{
return prevStage->size > 0;
return prevStage->insts.size() > 0;
}
bool
@ -382,7 +381,8 @@ PipelineStage::squashPrevStageInsts(InstSeqNum squash_seq_num, ThreadID tid)
DPRINTF(InOrderStage, "[tid:%i]: Removing instructions from "
"incoming stage queue.\n", tid);
for (int i=0; i < prevStage->size; i++) {
int insts_from_prev_stage = prevStage->insts.size();
for (int i=0; i < insts_from_prev_stage; i++) {
if (prevStage->insts[i]->threadNumber == tid &&
prevStage->insts[i]->seqNum > squash_seq_num) {
// Change Comment to Annulling previous instruction
@ -441,16 +441,8 @@ PipelineStage::stageBufferAvail()
total += skidBuffer[i].size();
}
int incoming_insts = (prevStageValid) ?
cpu->pipelineStage[stageNum]->prevStage->size :
0;
int avail = stageBufferMax - total;
if (avail < 0)
fatal("stageNum %i:stageBufferAvail() < 0..."
"stBMax=%i,total=%i,incoming=%i=>%i",
stageNum, stageBufferMax, total, incoming_insts, avail);
assert(avail >= 0);
return avail;
}
@ -462,7 +454,7 @@ PipelineStage::canSendInstToStage(unsigned stage_num)
if (cpu->pipelineStage[stage_num]->prevStageValid) {
buffer_avail = cpu->pipelineStage[stage_num]->stageBufferAvail() -
cpu->pipelineStage[stage_num-1]->nextStage->size >= 1;
cpu->pipelineStage[stage_num-1]->nextStage->insts.size() >= 1;
}
if (!buffer_avail && nextStageQueueValid(stage_num)) {
@ -576,7 +568,9 @@ void
PipelineStage::sortInsts()
{
if (prevStageValid) {
int insts_from_prev_stage = prevStage->size;
assert(prevStage->insts.size() <= stageWidth);
int insts_from_prev_stage = prevStage->insts.size();
int insts_from_cur_stage = skidSize();
DPRINTF(InOrderStage, "%i insts available from stage buffer %i. Stage "
"currently has %i insts from last cycle.\n",
@ -591,7 +585,6 @@ PipelineStage::sortInsts()
"not inserting into stage buffer.\n",
prevStage->insts[i]->readTid(),
prevStage->insts[i]->seqNum);
prevStage->size--;
continue;
}
@ -619,12 +612,8 @@ PipelineStage::sortInsts()
prevStage->insts[i] = cpu->dummyBufferInst;
prevStage->size--;
inserted_insts++;
}
assert(prevStage->size == 0);
}
}
@ -728,11 +717,6 @@ PipelineStage::tick()
wroteToTimeBuffer = false;
bool status_change = false;
if (nextStageValid)
nextStage->size = 0;
toNextStageIndex = 0;
sortInsts();
@ -807,7 +791,7 @@ PipelineStage::processStage(bool &status_change)
if (nextStageValid) {
DPRINTF(InOrderStage, "%i insts now available for stage %i.\n",
nextStage->size, stageNum + 1);
nextStage->insts.size(), stageNum + 1);
}
if (instsProcessed > 0) {
@ -1083,20 +1067,13 @@ PipelineStage::sendInstToNextStage(DynInstPtr inst)
DPRINTF(InOrderStage, "[tid:%u]: [sn:%i]: being placed into "
"index %i of stage buffer %i queue.\n",
tid, inst->seqNum, toNextStageIndex,
tid, inst->seqNum,
cpu->pipelineStage[prev_stage]->nextStage->insts.size(),
cpu->pipelineStage[prev_stage]->nextStageQueue->id());
int next_stage_idx =
cpu->pipelineStage[prev_stage]->nextStage->size;
// Place instructions in inter-stage communication struct for next
// pipeline stage to read next cycle
cpu->pipelineStage[prev_stage]->nextStage->insts[next_stage_idx]
= inst;
++(cpu->pipelineStage[prev_stage]->nextStage->size);
++toNextStageIndex;
cpu->pipelineStage[prev_stage]->nextStage->insts.push_back(inst);
success = true;

14
src/cpu/inorder/pipeline_traits.hh
View file

@ -52,7 +52,6 @@ namespace ThePipeline {
// Pipeline Constants
const unsigned NumStages = 5;
const ThreadID MaxThreads = 8;
const unsigned StageWidth = 1;
const unsigned BackEndStartStage = 2;
// List of Resources The Pipeline Uses
@ -71,19 +70,6 @@ namespace ThePipeline {
FetchBuff2
};
// Expand this as necessary for your inter stage buffer sizes
static const unsigned interStageBuffSize[] = {
StageWidth, /* Stage 0 - 1 */
StageWidth, /* Stage 1 - 2 */
StageWidth, /* Stage 2 - 3 */
StageWidth, /* Stage 3 - 4 */
StageWidth, /* Stage 4 - 5 */
StageWidth, /* Stage 5 - 6 */
StageWidth, /* Stage 6 - 7 */
StageWidth, /* Stage 7 - 8 */
StageWidth /* Stage 8 - 9 */
};
typedef InOrderCPUParams Params;
typedef RefCountingPtr<InOrderDynInst> DynInstPtr;

20
src/cpu/inorder/resource_pool.cc
View file

@ -45,46 +45,48 @@ ResourcePool::ResourcePool(InOrderCPU *_cpu, ThePipeline::Params *params)
//This will help in the auto-generation of this pipeline model.
//ThePipeline::addResources(resources, memObjects);
int stage_width = cpu->stageWidth;
// Declare Resource Objects
// name - id - bandwidth - latency - CPU - Parameters
// --------------------------------------------------
resources.push_back(new FetchSeqUnit("Fetch-Seq-Unit", FetchSeq,
StageWidth * 2, 0, _cpu, params));
stage_width * 2, 0, _cpu, params));
memObjects.push_back(ICache);
resources.push_back(new CacheUnit("icache_port", ICache,
StageWidth * MaxThreads, 0, _cpu,
stage_width * MaxThreads, 0, _cpu,
params));
resources.push_back(new DecodeUnit("Decode-Unit", Decode,
StageWidth, 0, _cpu, params));
stage_width, 0, _cpu, params));
resources.push_back(new BranchPredictor("Branch-Predictor", BPred,
StageWidth, 0, _cpu, params));
stage_width, 0, _cpu, params));
resources.push_back(new InstBuffer("Fetch-Buffer-T0", FetchBuff, 4,
0, _cpu, params));
resources.push_back(new UseDefUnit("RegFile-Manager", RegManager,
StageWidth * MaxThreads, 0, _cpu,
stage_width * MaxThreads, 0, _cpu,
params));
resources.push_back(new AGENUnit("AGEN-Unit", AGEN,
StageWidth, 0, _cpu, params));
stage_width, 0, _cpu, params));
resources.push_back(new ExecutionUnit("Execution-Unit", ExecUnit,
StageWidth, 0, _cpu, params));
stage_width, 0, _cpu, params));
resources.push_back(new MultDivUnit("Mult-Div-Unit", MDU, 5, 0, _cpu,
params));
memObjects.push_back(DCache);
resources.push_back(new CacheUnit("dcache_port", DCache,
StageWidth * MaxThreads, 0, _cpu,
stage_width * MaxThreads, 0, _cpu,
params));
resources.push_back(new GraduationUnit("Graduation-Unit", Grad,
StageWidth * MaxThreads, 0, _cpu,
stage_width * MaxThreads, 0, _cpu,
params));
resources.push_back(new InstBuffer("Fetch-Buffer-T1", FetchBuff2, 4,