| // Copyright 2015 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "src/compiler/js-inlining-heuristic.h" |
| |
| #include "src/compiler.h" |
| #include "src/compiler/node-matchers.h" |
| #include "src/objects-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| namespace compiler { |
| |
| Reduction JSInliningHeuristic::Reduce(Node* node) { |
| if (!IrOpcode::IsInlineeOpcode(node->opcode())) return NoChange(); |
| |
| // Check if we already saw that {node} before, and if so, just skip it. |
| if (seen_.find(node->id()) != seen_.end()) return NoChange(); |
| seen_.insert(node->id()); |
| |
| Node* callee = node->InputAt(0); |
| HeapObjectMatcher match(callee); |
| if (!match.HasValue() || !match.Value()->IsJSFunction()) return NoChange(); |
| Handle<JSFunction> function = Handle<JSFunction>::cast(match.Value()); |
| |
| // Functions marked with %SetForceInlineFlag are immediately inlined. |
| if (function->shared()->force_inline()) { |
| return inliner_.ReduceJSCall(node, function); |
| } |
| |
| // Handling of special inlining modes right away: |
| // - For restricted inlining: stop all handling at this point. |
| // - For stressing inlining: immediately handle all functions. |
| switch (mode_) { |
| case kRestrictedInlining: |
| return NoChange(); |
| case kStressInlining: |
| return inliner_.ReduceJSCall(node, function); |
| case kGeneralInlining: |
| break; |
| } |
| |
| // --------------------------------------------------------------------------- |
| // Everything below this line is part of the inlining heuristic. |
| // --------------------------------------------------------------------------- |
| |
| // Built-in functions are handled by the JSBuiltinReducer. |
| if (function->shared()->HasBuiltinFunctionId()) return NoChange(); |
| |
| // Don't inline builtins. |
| if (function->shared()->IsBuiltin()) return NoChange(); |
| |
| // Quick check on source code length to avoid parsing large candidate. |
| if (function->shared()->SourceSize() > FLAG_max_inlined_source_size) { |
| return NoChange(); |
| } |
| |
| // Quick check on the size of the AST to avoid parsing large candidate. |
| if (function->shared()->ast_node_count() > FLAG_max_inlined_nodes) { |
| return NoChange(); |
| } |
| |
| // Avoid inlining within or across the boundary of asm.js code. |
| if (info_->shared_info()->asm_function()) return NoChange(); |
| if (function->shared()->asm_function()) return NoChange(); |
| |
| // Stop inlinining once the maximum allowed level is reached. |
| int level = 0; |
| for (Node* frame_state = NodeProperties::GetFrameStateInput(node, 0); |
| frame_state->opcode() == IrOpcode::kFrameState; |
| frame_state = NodeProperties::GetFrameStateInput(frame_state, 0)) { |
| if (++level > FLAG_max_inlining_levels) return NoChange(); |
| } |
| |
| // Gather feedback on how often this call site has been hit before. |
| int calls = -1; // Same default as CallICNexus::ExtractCallCount. |
| // TODO(turbofan): We also want call counts for constructor calls. |
| if (node->opcode() == IrOpcode::kJSCallFunction) { |
| CallFunctionParameters p = CallFunctionParametersOf(node->op()); |
| if (p.feedback().IsValid()) { |
| CallICNexus nexus(p.feedback().vector(), p.feedback().slot()); |
| calls = nexus.ExtractCallCount(); |
| } |
| } |
| |
| // --------------------------------------------------------------------------- |
| // Everything above this line is part of the inlining heuristic. |
| // --------------------------------------------------------------------------- |
| |
| // In the general case we remember the candidate for later. |
| candidates_.insert({function, node, calls}); |
| return NoChange(); |
| } |
| |
| |
| void JSInliningHeuristic::Finalize() { |
| if (candidates_.empty()) return; // Nothing to do without candidates. |
| if (FLAG_trace_turbo_inlining) PrintCandidates(); |
| |
| // We inline at most one candidate in every iteration of the fixpoint. |
| // This is to ensure that we don't consume the full inlining budget |
| // on things that aren't called very often. |
| // TODO(bmeurer): Use std::priority_queue instead of std::set here. |
| while (!candidates_.empty()) { |
| if (cumulative_count_ > FLAG_max_inlined_nodes_cumulative) return; |
| auto i = candidates_.begin(); |
| Candidate candidate = *i; |
| candidates_.erase(i); |
| // Make sure we don't try to inline dead candidate nodes. |
| if (!candidate.node->IsDead()) { |
| Reduction r = inliner_.ReduceJSCall(candidate.node, candidate.function); |
| if (r.Changed()) { |
| cumulative_count_ += candidate.function->shared()->ast_node_count(); |
| return; |
| } |
| } |
| } |
| } |
| |
| |
| bool JSInliningHeuristic::CandidateCompare::operator()( |
| const Candidate& left, const Candidate& right) const { |
| if (left.calls != right.calls) { |
| return left.calls > right.calls; |
| } |
| return left.node < right.node; |
| } |
| |
| |
| void JSInliningHeuristic::PrintCandidates() { |
| PrintF("Candidates for inlining (size=%zu):\n", candidates_.size()); |
| for (const Candidate& candidate : candidates_) { |
| PrintF(" id:%d, calls:%d, size[source]:%d, size[ast]:%d / %s\n", |
| candidate.node->id(), candidate.calls, |
| candidate.function->shared()->SourceSize(), |
| candidate.function->shared()->ast_node_count(), |
| candidate.function->shared()->DebugName()->ToCString().get()); |
| } |
| } |
| |
| } // namespace compiler |
| } // namespace internal |
| } // namespace v8 |