void checkOperand( BlockIndex blockIndex, Operands<size_t>& getLocalPositions, Operands<size_t>& setLocalPositions, int operand) { if (getLocalPositions.operand(operand) == notSet) return; if (setLocalPositions.operand(operand) == notSet) return; BasicBlock* block = m_graph.m_blocks[blockIndex].get(); VALIDATE( (block->at(getLocalPositions.operand(operand)), block->at(setLocalPositions.operand(operand)), blockIndex), getLocalPositions.operand(operand) < setLocalPositions.operand(operand)); }
bool run() { ASSERT(m_graph.m_form == SSA); for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) { BasicBlock* block = m_graph.block(blockIndex); if (!block) continue; block->ssa->availabilityAtHead.fill(Availability()); block->ssa->availabilityAtTail.fill(Availability()); } BasicBlock* root = m_graph.block(0); for (unsigned argument = root->ssa->availabilityAtHead.numberOfArguments(); argument--;) { root->ssa->availabilityAtHead.argument(argument) = Availability::unavailable().withFlush( FlushedAt(FlushedJSValue, virtualRegisterForArgument(argument))); } for (unsigned local = root->ssa->availabilityAtHead.numberOfLocals(); local--;) root->ssa->availabilityAtHead.local(local) = Availability::unavailable(); if (m_graph.m_plan.mode == FTLForOSREntryMode) { for (unsigned local = m_graph.m_profiledBlock->m_numCalleeRegisters; local--;) { root->ssa->availabilityAtHead.local(local) = Availability::unavailable().withFlush( FlushedAt(FlushedJSValue, virtualRegisterForLocal(local))); } } // This could be made more efficient by processing blocks in reverse postorder. Operands<Availability> availability; bool changed; do { changed = false; for (BlockIndex blockIndex = 0; blockIndex < m_graph.numBlocks(); ++blockIndex) { BasicBlock* block = m_graph.block(blockIndex); if (!block) continue; availability = block->ssa->availabilityAtHead; for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) { Node* node = block->at(nodeIndex); switch (node->op()) { case SetLocal: { VariableAccessData* variable = node->variableAccessData(); availability.operand(variable->local()) = Availability(node->child1().node(), variable->flushedAt()); break; } case GetArgument: { VariableAccessData* variable = node->variableAccessData(); availability.operand(variable->local()) = Availability(node, variable->flushedAt()); break; } case MovHint: case MovHintAndCheck: { VariableAccessData* variable = node->variableAccessData(); availability.operand(variable->local()) = Availability(node->child1().node()); break; } case ZombieHint: { VariableAccessData* variable = node->variableAccessData(); availability.operand(variable->local()) = Availability::unavailable(); break; } default: break; } } if (availability == block->ssa->availabilityAtTail) continue; block->ssa->availabilityAtTail = availability; changed = true; for (unsigned successorIndex = block->numSuccessors(); successorIndex--;) { BasicBlock* successor = block->successor(successorIndex); for (unsigned i = availability.size(); i--;) { successor->ssa->availabilityAtHead[i] = availability[i].merge( successor->ssa->availabilityAtHead[i]); } } } } while (changed); return true; }