llvm-6502/lib/Target/SparcV9/ModuloScheduling/MSSchedule.cpp

309 lines
9.2 KiB
C++

//===-- MSSchedule.cpp Schedule ---------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "ModuloSched"
#include "MSSchedule.h"
#include "llvm/Support/Debug.h"
#include "llvm/Target/TargetSchedInfo.h"
#include "../SparcV9Internals.h"
#include "llvm/CodeGen/MachineInstr.h"
using namespace llvm;
//Check if all resources are free
bool resourcesFree(MSchedGraphNode*, int,
std::map<int, std::map<int, int> > &resourceNumPerCycle);
//Returns a boolean indicating if the start cycle needs to be increased/decreased
bool MSSchedule::insert(MSchedGraphNode *node, int cycle, int II) {
//First, check if the cycle has a spot free to start
if(schedule.find(cycle) != schedule.end()) {
//Check if we have a free issue slot at this cycle
if (schedule[cycle].size() < numIssue) {
//Now check if all the resources in their respective cycles are available
if(resourcesFree(node, cycle, II)) {
//Insert to preserve dependencies
addToSchedule(cycle,node);
DEBUG(std::cerr << "Found spot in map, and there is an issue slot\n");
return false;
}
}
}
//Not in the map yet so put it in
else {
if(resourcesFree(node,cycle,II)) {
std::vector<MSchedGraphNode*> nodes;
nodes.push_back(node);
schedule[cycle] = nodes;
DEBUG(std::cerr << "Nothing in map yet so taking an issue slot\n");
return false;
}
}
DEBUG(std::cerr << "All issue slots taken\n");
return true;
}
void MSSchedule::addToSchedule(int cycle, MSchedGraphNode *node) {
std::vector<MSchedGraphNode*> nodesAtCycle = schedule[cycle];
std::map<unsigned, MSchedGraphNode*> indexMap;
for(unsigned i=0; i < nodesAtCycle.size(); ++i) {
indexMap[nodesAtCycle[i]->getIndex()] = nodesAtCycle[i];
}
indexMap[node->getIndex()] = node;
std::vector<MSchedGraphNode*> nodes;
for(std::map<unsigned, MSchedGraphNode*>::iterator I = indexMap.begin(), E = indexMap.end(); I != E; ++I)
nodes.push_back(I->second);
schedule[cycle] = nodes;
}
bool MSSchedule::resourceAvailable(int resourceNum, int cycle) {
bool isFree = true;
//Get Map for this cycle
if(resourceNumPerCycle.count(cycle)) {
if(resourceNumPerCycle[cycle].count(resourceNum)) {
int maxRes = CPUResource::getCPUResource(resourceNum)->maxNumUsers;
if(resourceNumPerCycle[cycle][resourceNum] >= maxRes)
isFree = false;
}
}
return isFree;
}
void MSSchedule::useResource(int resourceNum, int cycle) {
//Get Map for this cycle
if(resourceNumPerCycle.count(cycle)) {
if(resourceNumPerCycle[cycle].count(resourceNum)) {
resourceNumPerCycle[cycle][resourceNum]++;
}
else {
resourceNumPerCycle[cycle][resourceNum] = 1;
}
}
//If no map, create one!
else {
std::map<int, int> resourceUse;
resourceUse[resourceNum] = 1;
resourceNumPerCycle[cycle] = resourceUse;
}
}
bool MSSchedule::resourcesFree(MSchedGraphNode *node, int cycle, int II) {
//Get Resource usage for this instruction
const TargetSchedInfo *msi = node->getParent()->getTarget()->getSchedInfo();
int currentCycle = cycle;
bool success = true;
//Create vector of starting cycles
std::vector<int> cyclesMayConflict;
cyclesMayConflict.push_back(cycle);
if(resourceNumPerCycle.size() > 0) {
for(int i = cycle-II; i >= (resourceNumPerCycle.begin()->first); i-=II)
cyclesMayConflict.push_back(i);
for(int i = cycle+II; i <= resourceNumPerCycle.end()->first; i+=II)
cyclesMayConflict.push_back(i);
}
//Now check all cycles for conflicts
for(int index = 0; index < (int) cyclesMayConflict.size(); ++index) {
currentCycle = cyclesMayConflict[index];
//Get resource usage for this instruction
InstrRUsage rUsage = msi->getInstrRUsage(node->getInst()->getOpcode());
std::vector<std::vector<resourceId_t> > resources = rUsage.resourcesByCycle;
//Loop over resources in each cycle and increments their usage count
for(unsigned i=0; i < resources.size(); ++i) {
for(unsigned j=0; j < resources[i].size(); ++j) {
//Get Resource to check its availability
int resourceNum = resources[i][j];
DEBUG(std::cerr << "Attempting to schedule Resource Num: " << resourceNum << " in cycle: " << currentCycle << "\n");
success = resourceAvailable(resourceNum, currentCycle);
if(!success)
break;
}
if(!success)
break;
//Increase cycle
currentCycle++;
}
if(!success)
return false;
}
//Actually put resources into the map
if(success) {
int currentCycle = cycle;
//Get resource usage for this instruction
InstrRUsage rUsage = msi->getInstrRUsage(node->getInst()->getOpcode());
std::vector<std::vector<resourceId_t> > resources = rUsage.resourcesByCycle;
//Loop over resources in each cycle and increments their usage count
for(unsigned i=0; i < resources.size(); ++i) {
for(unsigned j=0; j < resources[i].size(); ++j) {
int resourceNum = resources[i][j];
useResource(resourceNum, currentCycle);
}
currentCycle++;
}
}
return true;
}
bool MSSchedule::constructKernel(int II, std::vector<MSchedGraphNode*> &branches, std::map<const MachineInstr*, unsigned> &indVar) {
//Our schedule is allowed to have negative numbers, so lets calculate this offset
int offset = schedule.begin()->first;
if(offset > 0)
offset = 0;
DEBUG(std::cerr << "Offset: " << offset << "\n");
//Using the schedule, fold up into kernel and check resource conflicts as we go
std::vector<std::pair<MSchedGraphNode*, int> > tempKernel;
int stageNum = ((schedule.rbegin()->first-offset)+1)/ II;
int maxSN = 0;
DEBUG(std::cerr << "Number of Stages: " << stageNum << "\n");
for(int index = offset; index < (II+offset); ++index) {
int count = 0;
for(int i = index; i <= (schedule.rbegin()->first); i+=II) {
if(schedule.count(i)) {
for(std::vector<MSchedGraphNode*>::iterator I = schedule[i].begin(),
E = schedule[i].end(); I != E; ++I) {
//Check if its a branch
assert(!(*I)->isBranch() && "Branch should not be schedule!");
tempKernel.push_back(std::make_pair(*I, count));
maxSN = std::max(maxSN, count);
}
}
++count;
}
}
//Add in induction var code
for(std::vector<std::pair<MSchedGraphNode*, int> >::iterator I = tempKernel.begin(), IE = tempKernel.end();
I != IE; ++I) {
//Add indVar instructions before this one for the current iteration
if(I->second == 0) {
std::map<unsigned, MachineInstr*> tmpMap;
//Loop over induction variable instructions in the map that come before this instr
for(std::map<const MachineInstr*, unsigned>::iterator N = indVar.begin(), NE = indVar.end(); N != NE; ++N) {
if(N->second < I->first->getIndex())
tmpMap[N->second] = (MachineInstr*) N->first;
}
//Add to kernel, and delete from indVar
for(std::map<unsigned, MachineInstr*>::iterator N = tmpMap.begin(), NE = tmpMap.end(); N != NE; ++N) {
kernel.push_back(std::make_pair(N->second, 0));
indVar.erase(N->second);
}
}
kernel.push_back(std::make_pair((MachineInstr*) I->first->getInst(), I->second));
}
std::map<unsigned, MachineInstr*> tmpMap;
//Add remaining invar instructions
for(std::map<const MachineInstr*, unsigned>::iterator N = indVar.begin(), NE = indVar.end(); N != NE; ++N) {
tmpMap[N->second] = (MachineInstr*) N->first;
}
//Add to kernel, and delete from indVar
for(std::map<unsigned, MachineInstr*>::iterator N = tmpMap.begin(), NE = tmpMap.end(); N != NE; ++N) {
kernel.push_back(std::make_pair(N->second, 0));
indVar.erase(N->second);
}
maxStage = maxSN;
return true;
}
bool MSSchedule::defPreviousStage(Value *def, int stage) {
//Loop over kernel and determine if value is being defined in previous stage
for(std::vector<std::pair<MachineInstr*, int> >::iterator P = kernel.begin(), PE = kernel.end(); P != PE; ++P) {
MachineInstr* inst = P->first;
//Loop over Machine Operands
for(unsigned i=0; i < inst->getNumOperands(); ++i) {
//get machine operand
const MachineOperand &mOp = inst->getOperand(i);
if(mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isDef()) {
if(def == mOp.getVRegValue()) {
if(P->second >= stage)
return false;
else
return true;
}
}
}
}
assert(0 && "We should always have found the def in our kernel\n");
}
void MSSchedule::print(std::ostream &os) const {
os << "Schedule:\n";
for(schedule_const_iterator I = schedule.begin(), E = schedule.end(); I != E; ++I) {
os << "Cycle: " << I->first << "\n";
for(std::vector<MSchedGraphNode*>::const_iterator node = I->second.begin(), nodeEnd = I->second.end(); node != nodeEnd; ++node)
os << **node << "\n";
}
os << "Kernel:\n";
for(std::vector<std::pair<MachineInstr*, int> >::const_iterator I = kernel.begin(),
E = kernel.end(); I != E; ++I)
os << "Node: " << *(I->first) << " Stage: " << I->second << "\n";
}