Initial support for different kinds of FU reservation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100645 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/ExactHazardRecognizer.cpp b/lib/CodeGen/ExactHazardRecognizer.cpp
index 52908ed..af5f289 100644
--- a/lib/CodeGen/ExactHazardRecognizer.cpp
+++ b/lib/CodeGen/ExactHazardRecognizer.cpp
@@ -45,14 +45,16 @@
}
}
- Scoreboard.reset(ScoreboardDepth);
+ ReservedScoreboard.reset(ScoreboardDepth);
+ RequiredScoreboard.reset(ScoreboardDepth);
DEBUG(dbgs() << "Using exact hazard recognizer: ScoreboardDepth = "
<< ScoreboardDepth << '\n');
}
void ExactHazardRecognizer::Reset() {
- Scoreboard.reset();
+ RequiredScoreboard.reset();
+ ReservedScoreboard.reset();
}
void ExactHazardRecognizer::ScoreBoard::dump() const {
@@ -86,10 +88,23 @@
// stage is occupied. FIXME it would be more accurate to find the
// same unit free in all the cycles.
for (unsigned int i = 0; i < IS->getCycles(); ++i) {
- assert(((cycle + i) < Scoreboard.getDepth()) &&
+ assert(((cycle + i) < RequiredScoreboard.getDepth()) &&
"Scoreboard depth exceeded!");
- unsigned freeUnits = IS->getUnits() & ~Scoreboard[cycle + i];
+ unsigned freeUnits = IS->getUnits();
+ switch (IS->getReservationKind()) {
+ default:
+ assert(0 && "Invalid FU reservation");
+ case InstrStage::Required:
+ // Required FUs conflict with both reserved and required ones
+ freeUnits &= ~ReservedScoreboard[cycle + i];
+ // FALLTHROUGH
+ case InstrStage::Reserved:
+ // Reserved FUs can conflict only with required ones.
+ freeUnits &= ~RequiredScoreboard[cycle + i];
+ break;
+ }
+
if (!freeUnits) {
DEBUG(dbgs() << "*** Hazard in cycle " << (cycle + i) << ", ");
DEBUG(dbgs() << "SU(" << SU->NodeNum << "): ");
@@ -114,16 +129,28 @@
// Use the itinerary for the underlying instruction to reserve FU's
// in the scoreboard at the appropriate future cycles.
unsigned idx = SU->getInstr()->getDesc().getSchedClass();
- for (const InstrStage *IS = ItinData.beginStage(idx),
+ for (const InstrStage *IS = ItinData.beginStage(idx),
*E = ItinData.endStage(idx); IS != E; ++IS) {
// We must reserve one of the stage's units for every cycle the
// stage is occupied. FIXME it would be more accurate to reserve
// the same unit free in all the cycles.
for (unsigned int i = 0; i < IS->getCycles(); ++i) {
- assert(((cycle + i) < Scoreboard.getDepth()) &&
+ assert(((cycle + i) < RequiredScoreboard.getDepth()) &&
"Scoreboard depth exceeded!");
- unsigned freeUnits = IS->getUnits() & ~Scoreboard[cycle + i];
+ unsigned freeUnits = IS->getUnits();
+ switch (IS->getReservationKind()) {
+ default:
+ assert(0 && "Invalid FU reservation");
+ case InstrStage::Required:
+ // Required FUs conflict with both reserved and required ones
+ freeUnits &= ~ReservedScoreboard[cycle + i];
+ // FALLTHROUGH
+ case InstrStage::Reserved:
+ // Reserved FUs can conflict only with required ones.
+ freeUnits &= ~RequiredScoreboard[cycle + i];
+ break;
+ }
// reduce to a single unit
unsigned freeUnit = 0;
@@ -133,17 +160,21 @@
} while (freeUnits);
assert(freeUnit && "No function unit available!");
- Scoreboard[cycle + i] |= freeUnit;
+ if (IS->getReservationKind() == InstrStage::Required)
+ RequiredScoreboard[cycle + i] |= freeUnit;
+ else
+ ReservedScoreboard[cycle + i] |= freeUnit;
}
// Advance the cycle to the next stage.
cycle += IS->getNextCycles();
}
- DEBUG(Scoreboard.dump());
+ DEBUG(ReservedScoreboard.dump());
+ DEBUG(RequiredScoreboard.dump());
}
void ExactHazardRecognizer::AdvanceCycle() {
- Scoreboard[0] = 0;
- Scoreboard.advance();
+ ReservedScoreboard[0] = 0; ReservedScoreboard.advance();
+ RequiredScoreboard[0] = 0; RequiredScoreboard.advance();
}