Fix logic bug in finding retry slot in tally.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24188 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jim Laskey 2005-11-05 00:01:25 +00:00
parent 54f997d23f
commit a5e5bff8b8

View File

@ -101,15 +101,13 @@ private:
typedef typename std::vector<T>::iterator Iter;
// Tally iterator
/// SlotsAvailable - Returns the an iterator equal to Begin if all units
/// are available. Otherwise return an iterator to a better Begin.
Iter SlotsAvailable(Iter Begin, unsigned N, unsigned ResourceSet,
/// SlotsAvailable - Returns true if all units are available.
///
bool SlotsAvailable(Iter Begin, unsigned N, unsigned ResourceSet,
unsigned &Resource) {
assert(N && "Must check availability with N != 0");
// Determine end of interval
Iter End = Begin + N;
// Alternate result
Iter Better = End;
assert(End <= Tally.end() && "Tally is not large enough for schedule");
// Iterate thru each resource
@ -126,15 +124,31 @@ private:
if (Interval == Begin) {
// Success
Resource = Res;
return Begin;
return true;
}
if (Better > Interval) Better = Interval;
}
// No luck
Resource = 0;
return Better;
return false;
}
/// RetrySlot - Finds a good candidate slot to retry search.
Iter RetrySlot(Iter Begin, unsigned N, unsigned ResourceSet) {
assert(N && "Must check availability with N != 0");
// Determine end of interval
Iter End = Begin + N;
assert(End <= Tally.end() && "Tally is not large enough for schedule");
while (Begin != End--) {
// Clear units in use
ResourceSet &= ~*End;
// If no units left then we should go no further
if (!ResourceSet) return End + 1;
}
// Made it all the way through
return Begin;
}
/// FindAndReserveStages - Return true if the stages can be completed. If
/// so mark as busy.
@ -146,7 +160,7 @@ private:
unsigned N = Stage->Cycles;
// Check to see if N slots are available, if not fail
unsigned Resource;
if (SlotsAvailable(Begin, N, Stage->Units, Resource) != Begin) return false;
if (!SlotsAvailable(Begin, N, Stage->Units, Resource)) return false;
// Check to see if remaining stages are available, if not fail
if (!FindAndReserveStages(Begin + N, Stage + 1, StageEnd)) return false;
// Reserve resource
@ -177,9 +191,7 @@ private:
// Try at cursor, if successful return position.
if (FindAndReserveStages(Cursor, StageBegin, StageEnd)) return Cursor;
// Locate a better position
unsigned Resource;
Cursor = SlotsAvailable(Cursor + 1, StageBegin->Cycles, StageBegin->Units,
Resource);
Cursor = RetrySlot(Cursor + 1, StageBegin->Cycles, StageBegin->Units);
}
}
@ -194,7 +206,13 @@ public:
// as busy.
unsigned FindAndReserve(unsigned Slot, InstrStage *StageBegin,
InstrStage *StageEnd) {
return FindSlots(Tally.begin() + Slot, StageBegin, StageEnd)-Tally.begin();
// Where to begin
Iter Begin = Tally.begin() + Slot;
// Find a free slot
Iter Where = FindSlots(Begin, StageBegin, StageEnd);
// Distance is slot number
unsigned Final = Where - Tally.begin();
return Final;
}
};
@ -718,7 +736,7 @@ void SimpleSched::IdentifyGroups() {
/// GatherSchedulingInfo - Get latency and resource information about each node.
///
void SimpleSched::GatherSchedulingInfo() {
// Get instruction itineraries for the target
const InstrItineraryData InstrItins = TM.getInstrItineraryData();
// For each node
@ -781,7 +799,7 @@ void SimpleSched::GatherSchedulingInfo() {
if (!Group->getDominator()) {
NIIterator NGI = Group->group_begin(), NGE = Group->group_end();
NodeInfo *Dominator = *NGI;
unsigned Latency = Dominator->Latency;
unsigned Latency = 0;
for (NGI++; NGI != NGE; NGI++) {
NodeInfo* NGNI = *NGI;