--- /dev/null
+/*
+ * Copyright (C) 2013, 2014 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "DFGOSREntrypointCreationPhase.h"
+
+#if ENABLE(DFG_JIT)
+
+#include "DFGBasicBlockInlines.h"
+#include "DFGBlockInsertionSet.h"
+#include "DFGGraph.h"
+#include "DFGLoopPreHeaderCreationPhase.h"
+#include "DFGPhase.h"
+#include "JSCInlines.h"
+
+namespace JSC { namespace DFG {
+
+class OSREntrypointCreationPhase : public Phase {
+public:
+ OSREntrypointCreationPhase(Graph& graph)
+ : Phase(graph, "OSR entrypoint creation")
+ {
+ }
+
+ bool run()
+ {
+ RELEASE_ASSERT(m_graph.m_plan.mode == FTLForOSREntryMode);
+ RELEASE_ASSERT(m_graph.m_form == ThreadedCPS);
+
+ unsigned bytecodeIndex = m_graph.m_plan.osrEntryBytecodeIndex;
+ RELEASE_ASSERT(bytecodeIndex);
+ RELEASE_ASSERT(bytecodeIndex != UINT_MAX);
+
+ // Needed by createPreHeader().
+ m_graph.m_dominators.computeIfNecessary(m_graph);
+
+ CodeBlock* baseline = m_graph.m_profiledBlock;
+
+ BasicBlock* target = 0;
+ for (unsigned blockIndex = m_graph.numBlocks(); blockIndex--;) {
+ BasicBlock* block = m_graph.block(blockIndex);
+ if (!block)
+ continue;
+ unsigned nodeIndex = 0;
+ Node* firstNode = block->at(0);
+ while (firstNode->isSemanticallySkippable())
+ firstNode = block->at(++nodeIndex);
+ if (firstNode->op() == LoopHint
+ && firstNode->origin.semantic == CodeOrigin(bytecodeIndex)) {
+ target = block;
+ break;
+ }
+ }
+
+ if (!target) {
+ // This is a terrible outcome. It shouldn't often happen but it might
+ // happen and so we should defend against it. If it happens, then this
+ // compilation is a failure.
+ return false;
+ }
+
+ BlockInsertionSet insertionSet(m_graph);
+
+ // We say that the execution count of the entry block is 1, because we know for sure
+ // that this must be the case. Under our definition of executionCount, "1" means "once
+ // per invocation". We could have said NaN here, since that would ask any clients of
+ // executionCount to use best judgement - but that seems unnecessary since we know for
+ // sure what the executionCount should be in this case.
+ BasicBlock* newRoot = insertionSet.insert(0, 1);
+ NodeOrigin origin = target->at(0)->origin;
+
+ Vector<Node*> locals(baseline->m_numCalleeRegisters);
+ for (int local = 0; local < baseline->m_numCalleeRegisters; ++local) {
+ Node* previousHead = target->variablesAtHead.local(local);
+ if (!previousHead)
+ continue;
+ VariableAccessData* variable = previousHead->variableAccessData();
+ locals[local] = newRoot->appendNode(
+ m_graph, variable->prediction(), ExtractOSREntryLocal, origin,
+ OpInfo(variable->local().offset()));
+
+ newRoot->appendNode(
+ m_graph, SpecNone, MovHint, origin, OpInfo(variable->local().offset()),
+ Edge(locals[local]));
+ }
+
+ for (int argument = 0; argument < baseline->numParameters(); ++argument) {
+ Node* oldNode = target->variablesAtHead.argument(argument);
+ if (!oldNode) {
+ // Just for sanity, always have a SetArgument even if it's not needed.
+ oldNode = m_graph.m_arguments[argument];
+ }
+ Node* node = newRoot->appendNode(
+ m_graph, SpecNone, SetArgument, origin,
+ OpInfo(oldNode->variableAccessData()));
+ m_graph.m_arguments[argument] = node;
+ }
+
+ for (int local = 0; local < baseline->m_numCalleeRegisters; ++local) {
+ Node* previousHead = target->variablesAtHead.local(local);
+ if (!previousHead)
+ continue;
+ VariableAccessData* variable = previousHead->variableAccessData();
+ Node* node = locals[local];
+ newRoot->appendNode(
+ m_graph, SpecNone, SetLocal, origin, OpInfo(variable), Edge(node));
+ }
+
+ newRoot->appendNode(
+ m_graph, SpecNone, Jump, origin,
+ OpInfo(createPreHeader(m_graph, insertionSet, target)));
+
+ insertionSet.execute();
+ m_graph.resetReachability();
+ m_graph.killUnreachableBlocks();
+ return true;
+ }
+};
+
+bool performOSREntrypointCreation(Graph& graph)
+{
+ SamplingRegion samplingRegion("DFG OSR Entrypoint Creation");
+ return runPhase<OSREntrypointCreationPhase>(graph);
+}
+
+} } // namespace JSC::DFG
+
+#endif // ENABLE(DFG_JIT)
+
+
projects / apple / javascriptcore.git / blobdiff