llvm-6502/lib/CodeGen/InstrSched/SchedPriorities.h
Chris Lattner 179cdfb5c8 * Removed extraneous #includes
* Fixed file headers to be consistent with the rest of LLVM
* Other minor fixes


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3277 91177308-0d34-0410-b5e6-96231b3b80d8
2002-08-09 20:08:03 +00:00

210 lines
6.3 KiB
C++

//===-- SchedPriorities.h - Encapsulate scheduling heuristics --*- C++ -*--===//
//
// Strategy:
// Priority ordering rules:
// (1) Max delay, which is the order of the heap S.candsAsHeap.
// (2) Instruction that frees up a register.
// (3) Instruction that has the maximum number of dependent instructions.
// Note that rules 2 and 3 are only used if issue conflicts prevent
// choosing a higher priority instruction by rule 1.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_SCHEDPRIORITIES_H
#define LLVM_CODEGEN_SCHEDPRIORITIES_H
#include "SchedGraph.h"
#include "llvm/CodeGen/InstrScheduling.h"
#include "llvm/Target/MachineSchedInfo.h"
#include <list>
#include <Support/hash_set>
class Function;
class MachineInstr;
class SchedulingManager;
class FunctionLiveVarInfo;
//---------------------------------------------------------------------------
// Debug option levels for instruction scheduling
enum SchedDebugLevel_t {
Sched_NoDebugInfo,
Sched_Disable,
Sched_PrintMachineCode,
Sched_PrintSchedTrace,
Sched_PrintSchedGraphs,
};
extern SchedDebugLevel_t SchedDebugLevel;
//---------------------------------------------------------------------------
// Function: instrIsFeasible
//
// Purpose:
// Used by the priority analysis to filter out instructions
// that are not feasible to issue in the current cycle.
// Should only be used during schedule construction..
//---------------------------------------------------------------------------
bool instrIsFeasible(const SchedulingManager &S, MachineOpCode opCode);
struct NodeDelayPair {
const SchedGraphNode* node;
cycles_t delay;
NodeDelayPair(const SchedGraphNode* n, cycles_t d) : node(n), delay(d) {}
inline bool operator<(const NodeDelayPair& np) { return delay < np.delay; }
};
inline bool
NDPLessThan(const NodeDelayPair* np1, const NodeDelayPair* np2)
{
return np1->delay < np2->delay;
}
class NodeHeap: public std::list<NodeDelayPair*>, public NonCopyable {
public:
typedef std::list<NodeDelayPair*>::iterator iterator;
typedef std::list<NodeDelayPair*>::const_iterator const_iterator;
public:
NodeHeap() : _size(0) {}
inline unsigned size() const { return _size; }
const SchedGraphNode* getNode (const_iterator i) const { return (*i)->node; }
cycles_t getDelay(const_iterator i) const { return (*i)->delay;}
inline void makeHeap() {
// make_heap(begin(), end(), NDPLessThan);
}
inline iterator findNode(const SchedGraphNode* node) {
for (iterator I=begin(); I != end(); ++I)
if (getNode(I) == node)
return I;
return end();
}
inline void removeNode (const SchedGraphNode* node) {
iterator ndpPtr = findNode(node);
if (ndpPtr != end())
{
delete *ndpPtr;
erase(ndpPtr);
--_size;
}
};
void insert(const SchedGraphNode* node, cycles_t delay) {
NodeDelayPair* ndp = new NodeDelayPair(node, delay);
if (_size == 0 || front()->delay < delay)
push_front(ndp);
else
{
iterator I=begin();
for ( ; I != end() && getDelay(I) >= delay; ++I)
;
std::list<NodeDelayPair*>::insert(I, ndp);
}
_size++;
}
private:
unsigned int _size;
};
class SchedPriorities: public NonCopyable {
public:
SchedPriorities(const Function *F, const SchedGraph *G,
FunctionLiveVarInfo &LVI);
// This must be called before scheduling begins.
void initialize ();
cycles_t getTime () const { return curTime; }
cycles_t getEarliestReadyTime () const { return earliestReadyTime; }
unsigned getNumReady () const { return candsAsHeap.size(); }
bool nodeIsReady (const SchedGraphNode* node) const {
return (candsAsSet.find(node) != candsAsSet.end());
}
void issuedReadyNodeAt (cycles_t curTime,
const SchedGraphNode* node);
void insertReady (const SchedGraphNode* node);
void updateTime (cycles_t /*unused*/);
const SchedGraphNode* getNextHighest (const SchedulingManager& S,
cycles_t curTime);
// choose next highest priority instr
private:
typedef NodeHeap::iterator candIndex;
private:
cycles_t curTime;
const SchedGraph* graph;
FunctionLiveVarInfo &methodLiveVarInfo;
hash_map<const MachineInstr*, bool> lastUseMap;
std::vector<cycles_t> nodeDelayVec;
std::vector<cycles_t> nodeEarliestUseVec;
std::vector<cycles_t> earliestReadyTimeForNode;
cycles_t earliestReadyTime;
NodeHeap candsAsHeap; // candidate nodes, ready to go
hash_set<const SchedGraphNode*> candsAsSet; //same entries as candsAsHeap,
// but as set for fast lookup
std::vector<candIndex> mcands; // holds pointers into cands
candIndex nextToTry; // next cand after the last
// one tried in this cycle
int chooseByRule1 (std::vector<candIndex>& mcands);
int chooseByRule2 (std::vector<candIndex>& mcands);
int chooseByRule3 (std::vector<candIndex>& mcands);
void findSetWithMaxDelay (std::vector<candIndex>& mcands,
const SchedulingManager& S);
void computeDelays (const SchedGraph* graph);
void initializeReadyHeap (const SchedGraph* graph);
bool instructionHasLastUse (FunctionLiveVarInfo& LVI,
const SchedGraphNode* graphNode);
// NOTE: The next two return references to the actual vector entries.
// Use the following two if you don't need to modify the value.
cycles_t& getNodeDelayRef (const SchedGraphNode* node) {
assert(node->getNodeId() < nodeDelayVec.size());
return nodeDelayVec[node->getNodeId()];
}
cycles_t& getEarliestReadyTimeForNodeRef (const SchedGraphNode* node) {
assert(node->getNodeId() < earliestReadyTimeForNode.size());
return earliestReadyTimeForNode[node->getNodeId()];
}
cycles_t getNodeDelay (const SchedGraphNode* node) const {
return ((SchedPriorities*) this)->getNodeDelayRef(node);
}
cycles_t getEarliestReadyTimeForNode(const SchedGraphNode* node) const {
return ((SchedPriorities*) this)->getEarliestReadyTimeForNodeRef(node);
}
};
inline void SchedPriorities::updateTime(cycles_t c) {
curTime = c;
nextToTry = candsAsHeap.begin();
mcands.clear();
}
inline std::ostream &operator<<(std::ostream &os, const NodeDelayPair* nd) {
return os << "Delay for node " << nd->node->getNodeId()
<< " = " << (long)nd->delay << "\n";
}
#endif