diff options
Diffstat (limited to 'src/qml/compiler/qv4ssa_p.h')
| -rw-r--r-- | src/qml/compiler/qv4ssa_p.h | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/src/qml/compiler/qv4ssa_p.h b/src/qml/compiler/qv4ssa_p.h index e608c08591..386990a9f5 100644 --- a/src/qml/compiler/qv4ssa_p.h +++ b/src/qml/compiler/qv4ssa_p.h @@ -52,6 +52,7 @@ // #include "qv4jsir_p.h" +#include "qv4isel_util_p.h" #include <QtCore/QSharedPointer> QT_BEGIN_NAMESPACE @@ -277,6 +278,168 @@ private: QList<Move> &swaps) const; }; +/* + * stack slot allocation: + * + * foreach bb do + * foreach stmt do + * if the current statement is not a phi-node: + * purge ranges that end before the current statement + * check for life ranges to activate, and if they don't have a stackslot associated then allocate one + * renumber temps to stack + * for phi nodes: check if all temps (src+dst) are assigned stack slots and marked as allocated + * if it's a jump: + * foreach phi node in the successor: + * allocate slots for each temp (both sources and targets) if they don't have one allocated already + * insert moves before the jump + */ +class AllocateStackSlots: protected ConvertTemps +{ + IR::LifeTimeIntervals::Ptr _intervals; + QVector<IR::LifeTimeInterval *> _unhandled; + QVector<IR::LifeTimeInterval *> _live; + QBitArray _slotIsInUse; + IR::Function *_function; + + int defPosition(IR::Stmt *s) const + { + return usePosition(s) + 1; + } + + int usePosition(IR::Stmt *s) const + { + return _intervals->positionForStatement(s); + } + +public: + AllocateStackSlots(const IR::LifeTimeIntervals::Ptr &intervals) + : _intervals(intervals) + , _slotIsInUse(intervals->size(), false) + , _function(0) + { + _live.reserve(8); + _unhandled = _intervals->intervals(); + } + + void forFunction(IR::Function *function) + { + IR::Optimizer::showMeTheCode(function, "Before stack slot allocation"); + _function = function; + toStackSlots(function); + } + +protected: + virtual int allocateFreeSlot() + { + for (int i = 0, ei = _slotIsInUse.size(); i != ei; ++i) { + if (!_slotIsInUse[i]) { + if (_nextUnusedStackSlot <= i) { + Q_ASSERT(_nextUnusedStackSlot == i); + _nextUnusedStackSlot = i + 1; + } + _slotIsInUse[i] = true; + return i; + } + } + + Q_UNREACHABLE(); + return -1; + } + + virtual void process(IR::Stmt *s) + { +// qDebug("L%d statement %d:", _currentBasicBlock->index, s->id); + + if (IR::Phi *phi = s->asPhi()) { + visitPhi(phi); + } else { + // purge ranges no longer alive: + for (int i = 0; i < _live.size(); ) { + const IR::LifeTimeInterval *lti = _live.at(i); + if (lti->end() < usePosition(s)) { +// qDebug() << "\t - moving temp" << lti->temp().index << "to handled, freeing slot" << _stackSlotForTemp[lti->temp().index]; + _live.remove(i); + Q_ASSERT(_slotIsInUse[_stackSlotForTemp[lti->temp().index]]); + _slotIsInUse[_stackSlotForTemp[lti->temp().index]] = false; + continue; + } else { + ++i; + } + } + + // active new ranges: + while (!_unhandled.isEmpty()) { + IR::LifeTimeInterval *lti = _unhandled.last(); + if (lti->start() > defPosition(s)) + break; // we're done + Q_ASSERT(!_stackSlotForTemp.contains(lti->temp().index)); + _stackSlotForTemp[lti->temp().index] = allocateFreeSlot(); +// qDebug() << "\t - activating temp" << lti->temp().index << "on slot" << _stackSlotForTemp[lti->temp().index]; + _live.append(lti); + _unhandled.removeLast(); + } + + visit(s); + } + + if (IR::Jump *jump = s->asJump()) { + IR::MoveMapping moves; + for (IR::Stmt *succStmt : jump->target->statements()) { + if (IR::Phi *phi = succStmt->asPhi()) { + forceActivation(*phi->targetTemp); + for (int i = 0, ei = phi->incoming.size(); i != ei; ++i) { + IR::Expr *e = phi->incoming[i]; + if (IR::Temp *t = e->asTemp()) { + forceActivation(*t); + } + if (jump->target->in[i] == _currentBasicBlock) + moves.add(phi->incoming[i], phi->targetTemp); + } + } else { + break; + } + } + moves.order(); + QList<IR::Move *> newMoves = moves.insertMoves(_currentBasicBlock, _function, true); + foreach (IR::Move *move, newMoves) + visit(move); + } + } + + void forceActivation(const IR::Temp &t) + { + if (_stackSlotForTemp.contains(t.index)) + return; + + int i = _unhandled.size() - 1; + for (; i >= 0; --i) { + IR::LifeTimeInterval *lti = _unhandled[i]; + if (lti->temp() == t) { + _live.append(lti); + _unhandled.remove(i); + break; + } + } + Q_ASSERT(i >= 0); // check that we always found the entry + + _stackSlotForTemp[t.index] = allocateFreeSlot(); +// qDebug() << "\t - force activating temp" << t.index << "on slot" << _stackSlotForTemp[t.index]; + } + + virtual void visitPhi(IR::Phi *phi) + { + Q_UNUSED(phi); +#if !defined(QT_NO_DEBUG) + Q_ASSERT(_stackSlotForTemp.contains(phi->targetTemp->index)); + Q_ASSERT(_slotIsInUse[_stackSlotForTemp[phi->targetTemp->index]]); + foreach (IR::Expr *e, phi->incoming) { + if (IR::Temp *t = e->asTemp()) + Q_ASSERT(_stackSlotForTemp.contains(t->index)); + } +#endif // defined(QT_NO_DEBUG) + } +}; + } // IR namespace } // QV4 namespace |