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// 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/codegen/optimized-compilation-info.h"
#include "src/compiler/common-operator.h"
#include "src/compiler/compiler-source-position-table.h"
#include "src/compiler/js-heap-broker.h"
#include "src/compiler/node-matchers.h"
#include "src/compiler/simplified-operator.h"
#include "src/objects/objects-inl.h"
namespace v8 {
namespace internal {
namespace compiler {
#define TRACE(...) \
do { \
if (FLAG_trace_turbo_inlining) StdoutStream{} << __VA_ARGS__ << std::endl; \
} while (false)
namespace {
bool IsSmall(int const size) {
return size <= FLAG_max_inlined_bytecode_size_small;
}
bool CanConsiderForInlining(JSHeapBroker* broker,
SharedFunctionInfoRef const& shared,
FeedbackVectorRef const& feedback_vector) {
SharedFunctionInfo::Inlineability inlineability = shared.GetInlineability();
if (inlineability != SharedFunctionInfo::kIsInlineable) {
TRACE("Cannot consider "
<< shared << " for inlining (reason: " << inlineability << ")");
return false;
}
DCHECK(shared.HasBytecodeArray());
if (!broker->IsSerializedForCompilation(shared, feedback_vector)) {
TRACE_BROKER_MISSING(
broker, "data for " << shared << " (not serialized for compilation)");
TRACE("Cannot consider " << shared << " for inlining with "
<< feedback_vector << " (missing data)");
return false;
}
TRACE("Considering " << shared << " for inlining with " << feedback_vector);
return true;
}
bool CanConsiderForInlining(JSHeapBroker* broker,
JSFunctionRef const& function) {
if (!function.has_feedback_vector()) {
TRACE("Cannot consider " << function
<< " for inlining (no feedback vector)");
return false;
}
if (!function.serialized() || !function.serialized_code_and_feedback()) {
TRACE_BROKER_MISSING(
broker, "data for " << function << " (cannot consider for inlining)");
TRACE("Cannot consider " << function << " for inlining (missing data)");
return false;
}
return CanConsiderForInlining(broker, function.shared(),
function.feedback_vector());
}
} // namespace
JSInliningHeuristic::Candidate JSInliningHeuristic::CollectFunctions(
Node* node, int functions_size) {
DCHECK_NE(0, functions_size);
Node* callee = node->InputAt(0);
Candidate out;
out.node = node;
HeapObjectMatcher m(callee);
if (m.HasResolvedValue() && m.Ref(broker()).IsJSFunction()) {
out.functions[0] = m.Ref(broker()).AsJSFunction();
JSFunctionRef function = out.functions[0].value();
if (CanConsiderForInlining(broker(), function)) {
out.bytecode[0] = function.shared().GetBytecodeArray();
out.num_functions = 1;
return out;
}
}
if (m.IsPhi()) {
int const value_input_count = m.node()->op()->ValueInputCount();
if (value_input_count > functions_size) {
out.num_functions = 0;
return out;
}
for (int n = 0; n < value_input_count; ++n) {
HeapObjectMatcher m(callee->InputAt(n));
if (!m.HasResolvedValue() || !m.Ref(broker()).IsJSFunction()) {
out.num_functions = 0;
return out;
}
out.functions[n] = m.Ref(broker()).AsJSFunction();
JSFunctionRef function = out.functions[n].value();
if (CanConsiderForInlining(broker(), function)) {
out.bytecode[n] = function.shared().GetBytecodeArray();
}
}
out.num_functions = value_input_count;
return out;
}
if (m.IsCheckClosure()) {
DCHECK(!out.functions[0].has_value());
FeedbackCellRef feedback_cell(broker(), FeedbackCellOf(m.op()));
SharedFunctionInfoRef shared_info = *feedback_cell.shared_function_info();
out.shared_info = shared_info;
if (CanConsiderForInlining(broker(), shared_info, *feedback_cell.value())) {
out.bytecode[0] = shared_info.GetBytecodeArray();
}
out.num_functions = 1;
return out;
}
if (m.IsJSCreateClosure()) {
DCHECK(!out.functions[0].has_value());
JSCreateClosureNode n(callee);
CreateClosureParameters const& p = n.Parameters();
FeedbackCellRef feedback_cell = n.GetFeedbackCellRefChecked(broker());
SharedFunctionInfoRef shared_info(broker(), p.shared_info());
out.shared_info = shared_info;
if (feedback_cell.value().has_value() &&
CanConsiderForInlining(broker(), shared_info, *feedback_cell.value())) {
out.bytecode[0] = shared_info.GetBytecodeArray();
}
out.num_functions = 1;
return out;
}
out.num_functions = 0;
return out;
}
Reduction JSInliningHeuristic::Reduce(Node* node) {
#if V8_ENABLE_WEBASSEMBLY
if (mode() == kWasmOnly) {
if (node->opcode() == IrOpcode::kJSWasmCall) {
return inliner_.ReduceJSWasmCall(node);
}
return NoChange();
}
#endif // V8_ENABLE_WEBASSEMBLY
DCHECK_EQ(mode(), kJSOnly);
if (!IrOpcode::IsInlineeOpcode(node->opcode())) return NoChange();
if (total_inlined_bytecode_size_ >= FLAG_max_inlined_bytecode_size_absolute) {
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();
// Check if the {node} is an appropriate candidate for inlining.
Candidate candidate = CollectFunctions(node, kMaxCallPolymorphism);
if (candidate.num_functions == 0) {
return NoChange();
} else if (candidate.num_functions > 1 && !FLAG_polymorphic_inlining) {
TRACE("Not considering call site #"
<< node->id() << ":" << node->op()->mnemonic()
<< ", because polymorphic inlining is disabled");
return NoChange();
}
bool can_inline_candidate = false, candidate_is_small = true;
candidate.total_size = 0;
FrameState frame_state{NodeProperties::GetFrameStateInput(node)};
FrameStateInfo const& frame_info = frame_state.frame_state_info();
Handle<SharedFunctionInfo> frame_shared_info;
for (int i = 0; i < candidate.num_functions; ++i) {
if (!candidate.bytecode[i].has_value()) {
candidate.can_inline_function[i] = false;
continue;
}
SharedFunctionInfoRef shared = candidate.functions[i].has_value()
? candidate.functions[i].value().shared()
: candidate.shared_info.value();
candidate.can_inline_function[i] = candidate.bytecode[i].has_value();
CHECK_IMPLIES(candidate.can_inline_function[i], shared.IsInlineable());
// Do not allow direct recursion i.e. f() -> f(). We still allow indirect
// recurion like f() -> g() -> f(). The indirect recursion is helpful in
// cases where f() is a small dispatch function that calls the appropriate
// function. In the case of direct recursion, we only have some static
// information for the first level of inlining and it may not be that useful
// to just inline one level in recursive calls. In some cases like tail
// recursion we may benefit from recursive inlining, if we have additional
// analysis that converts them to iterative implementations. Though it is
// not obvious if such an anlysis is needed.
if (frame_info.shared_info().ToHandle(&frame_shared_info) &&
frame_shared_info.equals(shared.object())) {
TRACE("Not considering call site #" << node->id() << ":"
<< node->op()->mnemonic()
<< ", because of recursive inlining");
candidate.can_inline_function[i] = false;
}
if (candidate.can_inline_function[i]) {
can_inline_candidate = true;
BytecodeArrayRef bytecode = candidate.bytecode[i].value();
candidate.total_size += bytecode.length();
unsigned inlined_bytecode_size = 0;
if (candidate.functions[i].has_value()) {
JSFunctionRef function = candidate.functions[i].value();
inlined_bytecode_size = function.code().GetInlinedBytecodeSize();
candidate.total_size += inlined_bytecode_size;
}
candidate_is_small = candidate_is_small &&
IsSmall(bytecode.length() + inlined_bytecode_size);
}
}
if (!can_inline_candidate) return NoChange();
// Gather feedback on how often this call site has been hit before.
if (node->opcode() == IrOpcode::kJSCall) {
CallParameters const p = CallParametersOf(node->op());
candidate.frequency = p.frequency();
} else {
ConstructParameters const p = ConstructParametersOf(node->op());
candidate.frequency = p.frequency();
}
// Don't consider a {candidate} whose frequency is below the
// threshold, i.e. a call site that is only hit once every N
// invocations of the caller.
if (candidate.frequency.IsKnown() &&
candidate.frequency.value() < FLAG_min_inlining_frequency) {
return NoChange();
}
// Found a candidate. Insert it into the set of seen nodes s.t. we don't
// revisit in the future. Note this insertion happens here and not earlier in
// order to make inlining decisions order-independent. A node may not be a
// candidate when first seen, but later reductions may turn it into a valid
// candidate. In that case, the node should be revisited by
// JSInliningHeuristic.
seen_.insert(node->id());
// Forcibly inline small functions here. In the case of polymorphic inlining
// candidate_is_small is set only when all functions are small.
if (candidate_is_small) {
TRACE("Inlining small function(s) at call site #"
<< node->id() << ":" << node->op()->mnemonic());
return InlineCandidate(candidate, true);
}
// In the general case we remember the candidate for later.
candidates_.insert(candidate);
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()) {
auto i = candidates_.begin();
Candidate candidate = *i;
candidates_.erase(i);
// Ignore this candidate if it's no longer valid.
if (!IrOpcode::IsInlineeOpcode(candidate.node->opcode())) continue;
if (candidate.node->IsDead()) continue;
// Make sure we have some extra budget left, so that any small functions
// exposed by this function would be given a chance to inline.
double size_of_candidate =
candidate.total_size * FLAG_reserve_inline_budget_scale_factor;
int total_size =
total_inlined_bytecode_size_ + static_cast<int>(size_of_candidate);
if (total_size > FLAG_max_inlined_bytecode_size_cumulative) {
// Try if any smaller functions are available to inline.
continue;
}
Reduction const reduction = InlineCandidate(candidate, false);
if (reduction.Changed()) return;
}
}
namespace {
struct NodeAndIndex {
Node* node;
int index;
};
bool CollectStateValuesOwnedUses(Node* node, Node* state_values,
NodeAndIndex* uses_buffer, size_t* use_count,
size_t max_uses) {
// Only accumulate states that are not shared with other users.
if (state_values->UseCount() > 1) return true;
for (int i = 0; i < state_values->InputCount(); i++) {
Node* input = state_values->InputAt(i);
if (input->opcode() == IrOpcode::kStateValues) {
if (!CollectStateValuesOwnedUses(node, input, uses_buffer, use_count,
max_uses)) {
return false;
}
} else if (input == node) {
if (*use_count >= max_uses) return false;
uses_buffer[*use_count] = {state_values, i};
(*use_count)++;
}
}
return true;
}
} // namespace
Node* JSInliningHeuristic::DuplicateStateValuesAndRename(Node* state_values,
Node* from, Node* to,
StateCloneMode mode) {
// Only rename in states that are not shared with other users. This needs to
// be in sync with the condition in {CollectStateValuesOwnedUses}.
if (state_values->UseCount() > 1) return state_values;
Node* copy = mode == kChangeInPlace ? state_values : nullptr;
for (int i = 0; i < state_values->InputCount(); i++) {
Node* input = state_values->InputAt(i);
Node* processed;
if (input->opcode() == IrOpcode::kStateValues) {
processed = DuplicateStateValuesAndRename(input, from, to, mode);
} else if (input == from) {
processed = to;
} else {
processed = input;
}
if (processed != input) {
if (!copy) {
copy = graph()->CloneNode(state_values);
}
copy->ReplaceInput(i, processed);
}
}
return copy ? copy : state_values;
}
namespace {
bool CollectFrameStateUniqueUses(Node* node, FrameState frame_state,
NodeAndIndex* uses_buffer, size_t* use_count,
size_t max_uses) {
// Only accumulate states that are not shared with other users.
if (frame_state->UseCount() > 1) return true;
if (frame_state.stack() == node) {
if (*use_count >= max_uses) return false;
uses_buffer[*use_count] = {frame_state, FrameState::kFrameStateStackInput};
(*use_count)++;
}
if (!CollectStateValuesOwnedUses(node, frame_state.locals(), uses_buffer,
use_count, max_uses)) {
return false;
}
return true;
}
} // namespace
FrameState JSInliningHeuristic::DuplicateFrameStateAndRename(
FrameState frame_state, Node* from, Node* to, StateCloneMode mode) {
// Only rename in states that are not shared with other users. This needs to
// be in sync with the condition in {DuplicateFrameStateAndRename}.
if (frame_state->UseCount() > 1) return frame_state;
Node* copy =
mode == kChangeInPlace ? static_cast<Node*>(frame_state) : nullptr;
if (frame_state.stack() == from) {
if (!copy) {
copy = graph()->CloneNode(frame_state);
}
copy->ReplaceInput(FrameState::kFrameStateStackInput, to);
}
Node* locals = frame_state.locals();
Node* new_locals = DuplicateStateValuesAndRename(locals, from, to, mode);
if (new_locals != locals) {
if (!copy) {
copy = graph()->CloneNode(frame_state);
}
copy->ReplaceInput(FrameState::kFrameStateLocalsInput, new_locals);
}
return copy != nullptr ? FrameState{copy} : frame_state;
}
bool JSInliningHeuristic::TryReuseDispatch(Node* node, Node* callee,
Node** if_successes, Node** calls,
Node** inputs, int input_count) {
// We will try to reuse the control flow branch created for computing
// the {callee} target of the call. We only reuse the branch if there
// is no side-effect between the call and the branch, and if the callee is
// only used as the target (and possibly also in the related frame states).
// We are trying to match the following pattern:
//
// C1 C2
// . .
// | |
// Merge(merge) <-----------------+
// ^ ^ |
// V1 V2 | | E1 E2 |
// . . | +----+ . . |
// | | | | | | |
// Phi(callee) EffectPhi(effect_phi) |
// ^ ^ |
// | | |
// +----+ | |
// | | | |
// | StateValues | |
// | ^ | |
// +----+ | | |
// | | | | |
// | FrameState | |
// | ^ | |
// | | | +---+
// | | | | |
// +----+ Checkpoint(checkpoint) |
// | | ^ |
// | StateValues | +-------------+
// | | | |
// +-----+ | | |
// | | | | |
// | FrameState | |
// | ^ | |
// +-----------+ | | |
// Call(node)
// |
// |
// .
//
// The {callee} here is a phi that merges the possible call targets, {node}
// is the actual call that we will try to duplicate and connect to the
// control that comes into {merge}. There can be a {checkpoint} between
// the call and the calle phi.
//
// The idea is to get rid of the merge, effect phi and phi, then duplicate
// the call (with all the frame states and such), and connect the duplicated
// calls and states directly to the inputs of the ex-phi, ex-effect-phi and
// ex-merge. The tricky part is to make sure that there is no interference
// from the outside. In particular, there should not be any unaccounted uses
// of the phi, effect-phi and merge because we will remove them from
// the graph.
//
// V1 E1 C1 V2 E2 C2
// . . . . . .
// | | | | | |
// +----+ | | +----+ |
// | | | | | | |
// | StateValues | | | StateValues |
// | ^ | | | ^ |
// +----+ | | | +----+ | |
// | | | | | | | | |
// | FrameState | | | FrameState |
// | ^ | | | ^ |
// | | | | | | |
// | | | | | | |
// +----+ Checkpoint | +----+ Checkpoint |
// | | ^ | | | ^ |
// | StateValues | | | StateValues | |
// | | | | | | | |
// +-----+ | | | +-----+ | | |
// | | | | | | | | | |
// | FrameState | | | FrameState | |
// | ^ | | | ^ | |
// +-------------+| | | +-------------+| | |
// Call----+ Call----+
// | |
// +-------+ +------------+
// | |
// Merge
// EffectPhi
// Phi
// |
// ...
// Bailout if the call is not polymorphic anymore (other reducers might
// have replaced the callee phi with a constant).
if (callee->opcode() != IrOpcode::kPhi) return false;
int const num_calls = callee->op()->ValueInputCount();
// If there is a control node between the callee computation
// and the call, bail out.
Node* merge = NodeProperties::GetControlInput(callee);
if (NodeProperties::GetControlInput(node) != merge) return false;
// If there is a non-checkpoint effect node between the callee computation
// and the call, bail out. We will drop any checkpoint between the call and
// the callee phi because the callee computation should have its own
// checkpoint that the call can fall back to.
Node* checkpoint = nullptr;
Node* effect = NodeProperties::GetEffectInput(node);
if (effect->opcode() == IrOpcode::kCheckpoint) {
checkpoint = effect;
if (NodeProperties::GetControlInput(checkpoint) != merge) return false;
effect = NodeProperties::GetEffectInput(effect);
}
if (effect->opcode() != IrOpcode::kEffectPhi) return false;
if (NodeProperties::GetControlInput(effect) != merge) return false;
Node* effect_phi = effect;
// The effect phi, the callee, the call and the checkpoint must be the only
// users of the merge.
for (Node* merge_use : merge->uses()) {
if (merge_use != effect_phi && merge_use != callee && merge_use != node &&
merge_use != checkpoint) {
return false;
}
}
// The effect phi must be only used by the checkpoint or the call.
for (Node* effect_phi_use : effect_phi->uses()) {
if (effect_phi_use != node && effect_phi_use != checkpoint) return false;
}
// We must replace the callee phi with the appropriate constant in
// the entire subgraph reachable by inputs from the call (terminating
// at phis and merges). Since we do not want to walk (and later duplicate)
// the subgraph here, we limit the possible uses to this set:
//
// 1. In the call (as a target).
// 2. The checkpoint between the call and the callee computation merge.
// 3. The lazy deoptimization frame state.
//
// This corresponds to the most common pattern, where the function is
// called with only local variables or constants as arguments.
//
// To check the uses, we first collect all the occurrences of callee in 1, 2
// and 3, and then we check that all uses of callee are in the collected
// occurrences. If there is an unaccounted use, we do not try to rewire
// the control flow.
//
// Note: With CFG, this would be much easier and more robust - we would just
// duplicate all the nodes between the merge and the call, replacing all
// occurrences of the {callee} phi with the appropriate constant.
// First compute the set of uses that are only reachable from 2 and 3.
const size_t kMaxUses = 8;
NodeAndIndex replaceable_uses[kMaxUses];
size_t replaceable_uses_count = 0;
// Collect the uses to check case 2.
Node* checkpoint_state = nullptr;
if (checkpoint) {
checkpoint_state = checkpoint->InputAt(0);
if (!CollectFrameStateUniqueUses(callee, FrameState{checkpoint_state},
replaceable_uses, &replaceable_uses_count,
kMaxUses)) {
return false;
}
}
// Collect the uses to check case 3.
FrameState frame_state{NodeProperties::GetFrameStateInput(node)};
if (!CollectFrameStateUniqueUses(callee, frame_state, replaceable_uses,
&replaceable_uses_count, kMaxUses)) {
return false;
}
// Bail out if there is a use of {callee} that is not reachable from 1, 2
// and 3.
for (Edge edge : callee->use_edges()) {
// Case 1 (use by the call as a target).
if (edge.from() == node && edge.index() == 0) continue;
// Case 2 and 3 - used in checkpoint and/or lazy deopt frame states.
bool found = false;
for (size_t i = 0; i < replaceable_uses_count; i++) {
if (replaceable_uses[i].node == edge.from() &&
replaceable_uses[i].index == edge.index()) {
found = true;
break;
}
}
if (!found) return false;
}
// Clone the call and the framestate, including the uniquely reachable
// state values, making sure that we replace the phi with the constant.
for (int i = 0; i < num_calls; ++i) {
// Clone the calls for each branch.
// We need to specialize the calls to the correct target, effect, and
// control. We also need to duplicate the checkpoint and the lazy
// frame state, and change all the uses of the callee to the constant
// callee.
Node* target = callee->InputAt(i);
Node* effect = effect_phi->InputAt(i);
Node* control = merge->InputAt(i);
if (checkpoint) {
// Duplicate the checkpoint.
FrameState new_checkpoint_state = DuplicateFrameStateAndRename(
FrameState{checkpoint_state}, callee, target,
(i == num_calls - 1) ? kChangeInPlace : kCloneState);
effect = graph()->NewNode(checkpoint->op(), new_checkpoint_state, effect,
control);
}
// Duplicate the call.
FrameState new_lazy_frame_state = DuplicateFrameStateAndRename(
frame_state, callee, target,
(i == num_calls - 1) ? kChangeInPlace : kCloneState);
inputs[0] = target;
inputs[input_count - 3] = new_lazy_frame_state;
inputs[input_count - 2] = effect;
inputs[input_count - 1] = control;
calls[i] = if_successes[i] =
graph()->NewNode(node->op(), input_count, inputs);
}
// Mark the control inputs dead, so that we can kill the merge.
node->ReplaceInput(input_count - 1, jsgraph()->Dead());
callee->ReplaceInput(num_calls, jsgraph()->Dead());
effect_phi->ReplaceInput(num_calls, jsgraph()->Dead());
if (checkpoint) {
checkpoint->ReplaceInput(2, jsgraph()->Dead());
}
merge->Kill();
return true;
}
void JSInliningHeuristic::CreateOrReuseDispatch(Node* node, Node* callee,
Candidate const& candidate,
Node** if_successes,
Node** calls, Node** inputs,
int input_count) {
SourcePositionTable::Scope position(
source_positions_, source_positions_->GetSourcePosition(node));
if (TryReuseDispatch(node, callee, if_successes, calls, inputs,
input_count)) {
return;
}
STATIC_ASSERT(JSCallOrConstructNode::kHaveIdenticalLayouts);
Node* fallthrough_control = NodeProperties::GetControlInput(node);
int const num_calls = candidate.num_functions;
// Create the appropriate control flow to dispatch to the cloned calls.
for (int i = 0; i < num_calls; ++i) {
// TODO(2206): Make comparison be based on underlying SharedFunctionInfo
// instead of the target JSFunction reference directly.
Node* target = jsgraph()->Constant(candidate.functions[i].value());
if (i != (num_calls - 1)) {
Node* check =
graph()->NewNode(simplified()->ReferenceEqual(), callee, target);
Node* branch =
graph()->NewNode(common()->Branch(), check, fallthrough_control);
fallthrough_control = graph()->NewNode(common()->IfFalse(), branch);
if_successes[i] = graph()->NewNode(common()->IfTrue(), branch);
} else {
if_successes[i] = fallthrough_control;
}
// Clone the calls for each branch.
// The first input to the call is the actual target (which we specialize
// to the known {target}); the last input is the control dependency.
// We also specialize the new.target of JSConstruct {node}s if it refers
// to the same node as the {node}'s target input, so that we can later
// properly inline the JSCreate operations.
if (node->opcode() == IrOpcode::kJSConstruct) {
// TODO(jgruber, v8:10675): This branch seems unreachable.
JSConstructNode n(node);
if (inputs[n.TargetIndex()] == inputs[n.NewTargetIndex()]) {
inputs[n.NewTargetIndex()] = target;
}
}
inputs[JSCallOrConstructNode::TargetIndex()] = target;
inputs[input_count - 1] = if_successes[i];
calls[i] = if_successes[i] =
graph()->NewNode(node->op(), input_count, inputs);
}
}
Reduction JSInliningHeuristic::InlineCandidate(Candidate const& candidate,
bool small_function) {
int const num_calls = candidate.num_functions;
Node* const node = candidate.node;
#if V8_ENABLE_WEBASSEMBLY
DCHECK_NE(node->opcode(), IrOpcode::kJSWasmCall);
#endif // V8_ENABLE_WEBASSEMBLY
if (num_calls == 1) {
Reduction const reduction = inliner_.ReduceJSCall(node);
if (reduction.Changed()) {
total_inlined_bytecode_size_ += candidate.bytecode[0].value().length();
}
return reduction;
}
// Expand the JSCall/JSConstruct node to a subgraph first if
// we have multiple known target functions.
DCHECK_LT(1, num_calls);
Node* calls[kMaxCallPolymorphism + 1];
Node* if_successes[kMaxCallPolymorphism];
Node* callee = NodeProperties::GetValueInput(node, 0);
// Setup the inputs for the cloned call nodes.
int const input_count = node->InputCount();
Node** inputs = graph()->zone()->NewArray<Node*>(input_count);
for (int i = 0; i < input_count; ++i) {
inputs[i] = node->InputAt(i);
}
// Create the appropriate control flow to dispatch to the cloned calls.
CreateOrReuseDispatch(node, callee, candidate, if_successes, calls, inputs,
input_count);
// Check if we have an exception projection for the call {node}.
Node* if_exception = nullptr;
if (NodeProperties::IsExceptionalCall(node, &if_exception)) {
Node* if_exceptions[kMaxCallPolymorphism + 1];
for (int i = 0; i < num_calls; ++i) {
if_successes[i] = graph()->NewNode(common()->IfSuccess(), calls[i]);
if_exceptions[i] =
graph()->NewNode(common()->IfException(), calls[i], calls[i]);
}
// Morph the {if_exception} projection into a join.
Node* exception_control =
graph()->NewNode(common()->Merge(num_calls), num_calls, if_exceptions);
if_exceptions[num_calls] = exception_control;
Node* exception_effect = graph()->NewNode(common()->EffectPhi(num_calls),
num_calls + 1, if_exceptions);
Node* exception_value = graph()->NewNode(
common()->Phi(MachineRepresentation::kTagged, num_calls), num_calls + 1,
if_exceptions);
ReplaceWithValue(if_exception, exception_value, exception_effect,
exception_control);
}
// Morph the original call site into a join of the dispatched call sites.
Node* control =
graph()->NewNode(common()->Merge(num_calls), num_calls, if_successes);
calls[num_calls] = control;
Node* effect =
graph()->NewNode(common()->EffectPhi(num_calls), num_calls + 1, calls);
Node* value =
graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, num_calls),
num_calls + 1, calls);
ReplaceWithValue(node, value, effect, control);
// Inline the individual, cloned call sites.
for (int i = 0; i < num_calls && total_inlined_bytecode_size_ <
FLAG_max_inlined_bytecode_size_absolute;
++i) {
if (candidate.can_inline_function[i] &&
(small_function || total_inlined_bytecode_size_ <
FLAG_max_inlined_bytecode_size_cumulative)) {
Node* node = calls[i];
Reduction const reduction = inliner_.ReduceJSCall(node);
if (reduction.Changed()) {
total_inlined_bytecode_size_ += candidate.bytecode[i]->length();
// Killing the call node is not strictly necessary, but it is safer to
// make sure we do not resurrect the node.
node->Kill();
}
}
}
return Replace(value);
}
bool JSInliningHeuristic::CandidateCompare::operator()(
const Candidate& left, const Candidate& right) const {
if (right.frequency.IsUnknown()) {
if (left.frequency.IsUnknown()) {
// If left and right are both unknown then the ordering is indeterminate,
// which breaks strict weak ordering requirements, so we fall back to the
// node id as a tie breaker.
return left.node->id() > right.node->id();
}
return true;
} else if (left.frequency.IsUnknown()) {
return false;
} else if (left.frequency.value() > right.frequency.value()) {
return true;
} else if (left.frequency.value() < right.frequency.value()) {
return false;
} else {
return left.node->id() > right.node->id();
}
}
void JSInliningHeuristic::PrintCandidates() {
StdoutStream os;
os << candidates_.size() << " candidate(s) for inlining:" << std::endl;
for (const Candidate& candidate : candidates_) {
os << "- candidate: " << candidate.node->op()->mnemonic() << " node #"
<< candidate.node->id() << " with frequency " << candidate.frequency
<< ", " << candidate.num_functions << " target(s):" << std::endl;
for (int i = 0; i < candidate.num_functions; ++i) {
SharedFunctionInfoRef shared = candidate.functions[i].has_value()
? candidate.functions[i]->shared()
: candidate.shared_info.value();
os << " - target: " << shared;
if (candidate.bytecode[i].has_value()) {
os << ", bytecode size: " << candidate.bytecode[i]->length();
if (candidate.functions[i].has_value()) {
JSFunctionRef function = candidate.functions[i].value();
unsigned inlined_bytecode_size =
function.code().GetInlinedBytecodeSize();
if (inlined_bytecode_size > 0) {
os << ", existing opt code's inlined bytecode size: "
<< inlined_bytecode_size;
}
}
} else {
os << ", no bytecode";
}
os << std::endl;
}
}
}
Graph* JSInliningHeuristic::graph() const { return jsgraph()->graph(); }
CommonOperatorBuilder* JSInliningHeuristic::common() const {
return jsgraph()->common();
}
SimplifiedOperatorBuilder* JSInliningHeuristic::simplified() const {
return jsgraph()->simplified();
}
#undef TRACE
} // namespace compiler
} // namespace internal
} // namespace v8
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