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// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/flow_graph_inliner.h"
#include "vm/block_scheduler.h"
#include "vm/compiler.h"
#include "vm/flags.h"
#include "vm/flow_graph.h"
#include "vm/flow_graph_builder.h"
#include "vm/flow_graph_compiler.h"
#include "vm/flow_graph_optimizer.h"
#include "vm/il_printer.h"
#include "vm/intrinsifier.h"
#include "vm/longjump.h"
#include "vm/object.h"
#include "vm/object_store.h"
#include "vm/timer.h"
namespace dart {
DEFINE_FLAG(int, deoptimization_counter_inlining_threshold, 12,
"How many times we allow deoptimization before we stop inlining.");
DEFINE_FLAG(bool, trace_inlining, false, "Trace inlining");
DEFINE_FLAG(charp, inlining_filter, NULL, "Inline only in named function");
// Flags for inlining heuristics.
DEFINE_FLAG(int, inline_getters_setters_smaller_than, 10,
"Always inline getters and setters that have fewer instructions");
DEFINE_FLAG(int, inlining_depth_threshold, 6,
"Inline function calls up to threshold nesting depth");
DEFINE_FLAG(int, inlining_size_threshold, 25,
"Always inline functions that have threshold or fewer instructions");
DEFINE_FLAG(int, inlining_callee_call_sites_threshold, 1,
"Always inline functions containing threshold or fewer calls.");
DEFINE_FLAG(int, inlining_callee_size_threshold, 80,
"Do not inline callees larger than threshold");
DEFINE_FLAG(int, inlining_caller_size_threshold, 50000,
"Stop inlining once caller reaches the threshold.");
DEFINE_FLAG(int, inlining_constant_arguments_count, 1,
"Inline function calls with sufficient constant arguments "
"and up to the increased threshold on instructions");
DEFINE_FLAG(int, inlining_constant_arguments_max_size_threshold, 200,
"Do not inline callees larger than threshold if constant arguments");
DEFINE_FLAG(int, inlining_constant_arguments_min_size_threshold, 60,
"Inline function calls with sufficient constant arguments "
"and up to the increased threshold on instructions");
DEFINE_FLAG(int, inlining_hotness, 10,
"Inline only hotter calls, in percents (0 .. 100); "
"default 10%: calls above-equal 10% of max-count are inlined.");
DEFINE_FLAG(int, inlining_recursion_depth_threshold, 1,
"Inline recursive function calls up to threshold recursion depth.");
DEFINE_FLAG(int, max_inlined_per_depth, 500,
"Max. number of inlined calls per depth");
DEFINE_FLAG(bool, print_inlining_tree, false, "Print inlining tree");
DEFINE_FLAG(bool, enable_inlining_annotations, false,
"Enable inlining annotations");
DECLARE_FLAG(bool, compiler_stats);
DECLARE_FLAG(bool, enable_type_checks);
DECLARE_FLAG(int, deoptimization_counter_threshold);
DECLARE_FLAG(bool, print_flow_graph);
DECLARE_FLAG(bool, print_flow_graph_optimized);
DECLARE_FLAG(bool, verify_compiler);
// Quick access to the current zone.
#define Z (zone())
#define TRACE_INLINING(statement) \
do { \
if (trace_inlining()) statement; \
} while (false)
#define PRINT_INLINING_TREE(comment, caller, target, instance_call) \
do { \
if (FLAG_print_inlining_tree) { \
inlined_info_.Add(InlinedInfo( \
caller, target, inlining_depth_, instance_call, comment)); \
} \
} while (false) \
// Test if a call is recursive by looking in the deoptimization environment.
static bool IsCallRecursive(const Code& code, Definition* call) {
Environment* env = call->env();
while (env != NULL) {
if (code.raw() == env->code().raw()) {
return true;
}
env = env->outer();
}
return false;
}
// Helper to get the default value of a formal parameter.
static ConstantInstr* GetDefaultValue(intptr_t i,
const ParsedFunction& parsed_function) {
return new ConstantInstr(Object::ZoneHandle(
parsed_function.default_parameter_values().At(i)));
}
// Pair of an argument name and its value.
struct NamedArgument {
String* name;
Value* value;
NamedArgument(String* name, Value* value)
: name(name), value(value) { }
};
// Helper to collect information about a callee graph when considering it for
// inlining.
class GraphInfoCollector : public ValueObject {
public:
GraphInfoCollector()
: call_site_count_(0),
instruction_count_(0) { }
void Collect(const FlowGraph& graph) {
call_site_count_ = 0;
instruction_count_ = 0;
for (BlockIterator block_it = graph.postorder_iterator();
!block_it.Done();
block_it.Advance()) {
for (ForwardInstructionIterator it(block_it.Current());
!it.Done();
it.Advance()) {
++instruction_count_;
Instruction* current = it.Current();
if (current->IsStaticCall() ||
current->IsClosureCall()) {
++call_site_count_;
continue;
}
if (current->IsPolymorphicInstanceCall()) {
PolymorphicInstanceCallInstr* call =
current->AsPolymorphicInstanceCall();
// These checks make sure that the number of call-sites counted does
// not change relative to the time when the current set of inlining
// parameters was fixed.
// TODO(fschneider): Determine new heuristic parameters that avoid
// these checks entirely.
if (!call->HasSingleRecognizedTarget() &&
(call->instance_call()->token_kind() != Token::kEQ)) {
++call_site_count_;
}
}
}
}
}
intptr_t call_site_count() const { return call_site_count_; }
intptr_t instruction_count() const { return instruction_count_; }
private:
intptr_t call_site_count_;
intptr_t instruction_count_;
};
// Structure for collecting inline data needed to print inlining tree.
struct InlinedInfo {
const Function* caller;
const Function* inlined;
intptr_t inlined_depth;
const Definition* call_instr;
const char* bailout_reason;
InlinedInfo(const Function* caller_function,
const Function* inlined_function,
const intptr_t depth,
const Definition* call,
const char* reason)
: caller(caller_function),
inlined(inlined_function),
inlined_depth(depth),
call_instr(call),
bailout_reason(reason) {}
};
// A collection of call sites to consider for inlining.
class CallSites : public ValueObject {
public:
explicit CallSites(FlowGraph* flow_graph)
: static_calls_(),
closure_calls_(),
instance_calls_() { }
struct InstanceCallInfo {
PolymorphicInstanceCallInstr* call;
double ratio;
const FlowGraph* caller_graph;
InstanceCallInfo(PolymorphicInstanceCallInstr* call_arg,
FlowGraph* flow_graph)
: call(call_arg),
ratio(0.0),
caller_graph(flow_graph) {}
const Function& caller() const { return caller_graph->function(); }
};
struct StaticCallInfo {
StaticCallInstr* call;
double ratio;
FlowGraph* caller_graph;
StaticCallInfo(StaticCallInstr* value, FlowGraph* flow_graph)
: call(value),
ratio(0.0),
caller_graph(flow_graph) {}
const Function& caller() const { return caller_graph->function(); }
};
struct ClosureCallInfo {
ClosureCallInstr* call;
FlowGraph* caller_graph;
ClosureCallInfo(ClosureCallInstr* value, FlowGraph* flow_graph)
: call(value),
caller_graph(flow_graph) {}
const Function& caller() const { return caller_graph->function(); }
};
const GrowableArray<InstanceCallInfo>& instance_calls() const {
return instance_calls_;
}
const GrowableArray<StaticCallInfo>& static_calls() const {
return static_calls_;
}
const GrowableArray<ClosureCallInfo>& closure_calls() const {
return closure_calls_;
}
bool HasCalls() const {
return !(static_calls_.is_empty() &&
closure_calls_.is_empty() &&
instance_calls_.is_empty());
}
intptr_t NumCalls() const {
return instance_calls_.length() +
static_calls_.length() +
closure_calls_.length();
}
void Clear() {
static_calls_.Clear();
closure_calls_.Clear();
instance_calls_.Clear();
}
void ComputeCallSiteRatio(intptr_t static_call_start_ix,
intptr_t instance_call_start_ix) {
const intptr_t num_static_calls =
static_calls_.length() - static_call_start_ix;
const intptr_t num_instance_calls =
instance_calls_.length() - instance_call_start_ix;
intptr_t max_count = 0;
GrowableArray<intptr_t> instance_call_counts(num_instance_calls);
for (intptr_t i = 0; i < num_instance_calls; ++i) {
const intptr_t aggregate_count =
instance_calls_[i + instance_call_start_ix].
call->ic_data().AggregateCount();
instance_call_counts.Add(aggregate_count);
if (aggregate_count > max_count) max_count = aggregate_count;
}
GrowableArray<intptr_t> static_call_counts(num_static_calls);
for (intptr_t i = 0; i < num_static_calls; ++i) {
const intptr_t aggregate_count =
static_calls_[i + static_call_start_ix].
call->ic_data()->AggregateCount();
static_call_counts.Add(aggregate_count);
if (aggregate_count > max_count) max_count = aggregate_count;
}
// max_count can be 0 if none of the calls was executed.
for (intptr_t i = 0; i < num_instance_calls; ++i) {
const double ratio = (max_count == 0) ?
0.0 : static_cast<double>(instance_call_counts[i]) / max_count;
instance_calls_[i + instance_call_start_ix].ratio = ratio;
}
for (intptr_t i = 0; i < num_static_calls; ++i) {
const double ratio = (max_count == 0) ?
0.0 : static_cast<double>(static_call_counts[i]) / max_count;
static_calls_[i + static_call_start_ix].ratio = ratio;
}
}
static void RecordAllNotInlinedFunction(
FlowGraph* graph,
intptr_t depth,
GrowableArray<InlinedInfo>* inlined_info) {
const Function* caller = &graph->function();
Function& target = Function::ZoneHandle();
for (BlockIterator block_it = graph->postorder_iterator();
!block_it.Done();
block_it.Advance()) {
for (ForwardInstructionIterator it(block_it.Current());
!it.Done();
it.Advance()) {
Instruction* current = it.Current();
Definition* call = NULL;
if (current->IsPolymorphicInstanceCall()) {
PolymorphicInstanceCallInstr* instance_call =
current->AsPolymorphicInstanceCall();
target = instance_call->ic_data().GetTargetAt(0);
call = instance_call;
} else if (current->IsStaticCall()) {
StaticCallInstr* static_call = current->AsStaticCall();
target = static_call->function().raw();
call = static_call;
} else if (current->IsClosureCall()) {
// TODO(srdjan): Add data for closure calls.
}
if (call != NULL) {
inlined_info->Add(InlinedInfo(
caller, &target, depth + 1, call, "Too deep"));
}
}
}
}
void FindCallSites(FlowGraph* graph,
intptr_t depth,
GrowableArray<InlinedInfo>* inlined_info) {
ASSERT(graph != NULL);
if (depth > FLAG_inlining_depth_threshold) {
if (FLAG_print_inlining_tree) {
RecordAllNotInlinedFunction(graph, depth, inlined_info);
}
return;
}
// Recognized methods are not treated as normal calls. They don't have
// calls in themselves, so we keep adding those even when at the threshold.
const bool inline_only_recognized_methods =
(depth == FLAG_inlining_depth_threshold);
const intptr_t instance_call_start_ix = instance_calls_.length();
const intptr_t static_call_start_ix = static_calls_.length();
for (BlockIterator block_it = graph->postorder_iterator();
!block_it.Done();
block_it.Advance()) {
for (ForwardInstructionIterator it(block_it.Current());
!it.Done();
it.Advance()) {
Instruction* current = it.Current();
if (current->IsPolymorphicInstanceCall()) {
PolymorphicInstanceCallInstr* instance_call =
current->AsPolymorphicInstanceCall();
if (!inline_only_recognized_methods ||
instance_call->HasSingleRecognizedTarget() ||
instance_call->HasOnlyDispatcherTargets()) {
instance_calls_.Add(InstanceCallInfo(instance_call, graph));
} else {
// Method not inlined because inlining too deep and method
// not recognized.
if (FLAG_print_inlining_tree) {
const Function* caller = &graph->function();
const Function* target =
&Function::ZoneHandle(
instance_call->ic_data().GetTargetAt(0));
inlined_info->Add(InlinedInfo(
caller, target, depth + 1, instance_call, "Too deep"));
}
}
} else if (current->IsStaticCall()) {
StaticCallInstr* static_call = current->AsStaticCall();
if (!inline_only_recognized_methods ||
static_call->function().IsRecognized()) {
static_calls_.Add(StaticCallInfo(static_call, graph));
} else {
// Method not inlined because inlining too deep and method
// not recognized.
if (FLAG_print_inlining_tree) {
const Function* caller = &graph->function();
const Function* target = &static_call->function();
inlined_info->Add(InlinedInfo(
caller, target, depth + 1, static_call, "Too deep"));
}
}
} else if (current->IsClosureCall()) {
if (!inline_only_recognized_methods) {
ClosureCallInstr* closure_call = current->AsClosureCall();
closure_calls_.Add(ClosureCallInfo(closure_call, graph));
}
}
}
}
ComputeCallSiteRatio(static_call_start_ix, instance_call_start_ix);
}
private:
GrowableArray<StaticCallInfo> static_calls_;
GrowableArray<ClosureCallInfo> closure_calls_;
GrowableArray<InstanceCallInfo> instance_calls_;
DISALLOW_COPY_AND_ASSIGN(CallSites);
};
struct InlinedCallData {
InlinedCallData(Definition* call,
GrowableArray<Value*>* arguments,
const Function& caller,
intptr_t caller_inlining_id)
: call(call),
arguments(arguments),
callee_graph(NULL),
parameter_stubs(NULL),
exit_collector(NULL),
caller(caller),
caller_inlining_id_(caller_inlining_id) { }
Definition* call;
GrowableArray<Value*>* arguments;
FlowGraph* callee_graph;
ZoneGrowableArray<Definition*>* parameter_stubs;
InlineExitCollector* exit_collector;
const Function& caller;
const intptr_t caller_inlining_id_;
};
class CallSiteInliner;
class PolymorphicInliner : public ValueObject {
public:
PolymorphicInliner(CallSiteInliner* owner,
PolymorphicInstanceCallInstr* call,
const Function& caller_function,
intptr_t caller_inlining_id);
void Inline();
private:
bool CheckInlinedDuplicate(const Function& target);
bool CheckNonInlinedDuplicate(const Function& target);
bool TryInliningPoly(intptr_t receiver_cid, const Function& target);
bool TryInlineRecognizedMethod(intptr_t receiver_cid, const Function& target);
TargetEntryInstr* BuildDecisionGraph();
Isolate* isolate() const;
Zone* zone() const;
CallSiteInliner* const owner_;
PolymorphicInstanceCallInstr* const call_;
const intptr_t num_variants_;
GrowableArray<CidTarget> variants_;
GrowableArray<CidTarget> inlined_variants_;
GrowableArray<CidTarget> non_inlined_variants_;
GrowableArray<BlockEntryInstr*> inlined_entries_;
InlineExitCollector* exit_collector_;
const Function& caller_function_;
const intptr_t caller_inlining_id_;
};
static bool HasAnnotation(const Function& function, const char* annotation) {
const Class& owner = Class::Handle(function.Owner());
const Library& library = Library::Handle(owner.library());
const Array& metadata =
Array::Cast(Object::Handle(library.GetMetadata(function)));
if (metadata.Length() > 0) {
Object& val = Object::Handle();
for (intptr_t i = 0; i < metadata.Length(); i++) {
val = metadata.At(i);
if (val.IsString() && String::Cast(val).Equals(annotation)) {
return true;
}
}
}
return false;
}
class CallSiteInliner : public ValueObject {
public:
explicit CallSiteInliner(FlowGraphInliner* inliner)
: inliner_(inliner),
caller_graph_(inliner->flow_graph()),
inlined_(false),
initial_size_(inliner->flow_graph()->InstructionCount()),
inlined_size_(0),
inlined_recursive_call_(false),
inlining_depth_(1),
inlining_recursion_depth_(0),
collected_call_sites_(NULL),
inlining_call_sites_(NULL),
function_cache_(),
inlined_info_() { }
FlowGraph* caller_graph() const { return caller_graph_; }
Thread* thread() const { return caller_graph_->thread(); }
Isolate* isolate() const { return caller_graph_->isolate(); }
Zone* zone() const { return caller_graph_->zone(); }
bool trace_inlining() const { return inliner_->trace_inlining(); }
// Inlining heuristics based on Cooper et al. 2008.
bool ShouldWeInline(const Function& callee,
intptr_t instr_count,
intptr_t call_site_count,
intptr_t const_arg_count) {
if (inliner_->AlwaysInline(callee)) {
return true;
}
if (inlined_size_ > FLAG_inlining_caller_size_threshold) {
// Prevent methods becoming humongous and thus slow to compile.
return false;
}
if (const_arg_count > 0) {
if (instr_count > FLAG_inlining_constant_arguments_max_size_threshold) {
return false;
}
} else if (instr_count > FLAG_inlining_callee_size_threshold) {
return false;
}
// 'instr_count' can be 0 if it was not computed yet.
if ((instr_count != 0) && (instr_count <= FLAG_inlining_size_threshold)) {
return true;
}
if (call_site_count <= FLAG_inlining_callee_call_sites_threshold) {
return true;
}
if ((const_arg_count >= FLAG_inlining_constant_arguments_count) &&
(instr_count <= FLAG_inlining_constant_arguments_min_size_threshold)) {
return true;
}
return false;
}
void InlineCalls() {
// If inlining depth is less then one abort.
if (FLAG_inlining_depth_threshold < 1) return;
if (caller_graph_->function().deoptimization_counter() >=
FLAG_deoptimization_counter_inlining_threshold) {
return;
}
// Create two call site collections to swap between.
CallSites sites1(caller_graph_);
CallSites sites2(caller_graph_);
CallSites* call_sites_temp = NULL;
collected_call_sites_ = &sites1;
inlining_call_sites_ = &sites2;
// Collect initial call sites.
collected_call_sites_->FindCallSites(caller_graph_,
inlining_depth_,
&inlined_info_);
while (collected_call_sites_->HasCalls()) {
TRACE_INLINING(ISL_Print(" Depth %" Pd " ----------\n",
inlining_depth_));
if (collected_call_sites_->NumCalls() > FLAG_max_inlined_per_depth) {
break;
}
if (FLAG_print_inlining_tree) {
ISL_Print("**Depth % " Pd " calls to inline %" Pd "\n",
inlining_depth_, collected_call_sites_->NumCalls());
}
// Swap collected and inlining arrays and clear the new collecting array.
call_sites_temp = collected_call_sites_;
collected_call_sites_ = inlining_call_sites_;
inlining_call_sites_ = call_sites_temp;
collected_call_sites_->Clear();
// Inline call sites at the current depth.
InlineInstanceCalls();
InlineStaticCalls();
InlineClosureCalls();
// Increment the inlining depths. Checked before subsequent inlining.
++inlining_depth_;
if (inlined_recursive_call_) {
++inlining_recursion_depth_;
inlined_recursive_call_ = false;
}
}
collected_call_sites_ = NULL;
inlining_call_sites_ = NULL;
}
bool inlined() const { return inlined_; }
double GrowthFactor() const {
return static_cast<double>(inlined_size_) /
static_cast<double>(initial_size_);
}
// Helper to create a parameter stub from an actual argument.
Definition* CreateParameterStub(intptr_t i,
Value* argument,
FlowGraph* graph) {
ConstantInstr* constant = argument->definition()->AsConstant();
if (constant != NULL) {
return new(Z) ConstantInstr(constant->value());
} else {
return new(Z) ParameterInstr(i, graph->graph_entry());
}
}
bool TryInlining(const Function& function,
const Array& argument_names,
InlinedCallData* call_data) {
TRACE_INLINING(ISL_Print(" => %s (deopt count %d)\n",
function.ToCString(),
function.deoptimization_counter()));
// Make a handle for the unoptimized code so that it is not disconnected
// from the function while we are trying to inline it.
const Code& unoptimized_code = Code::Handle(function.unoptimized_code());
// Abort if the inlinable bit on the function is low.
if (!function.CanBeInlined()) {
TRACE_INLINING(ISL_Print(" Bailout: not inlinable\n"));
PRINT_INLINING_TREE("Not inlinable",
&call_data->caller, &function, call_data->call);
return false;
}
// Abort if this function has deoptimized too much.
if (function.deoptimization_counter() >=
FLAG_deoptimization_counter_threshold) {
function.set_is_inlinable(false);
TRACE_INLINING(ISL_Print(" Bailout: deoptimization threshold\n"));
PRINT_INLINING_TREE("Deoptimization threshold exceeded",
&call_data->caller, &function, call_data->call);
return false;
}
const char* kNeverInlineAnnotation = "NeverInline";
if (FLAG_enable_inlining_annotations &&
HasAnnotation(function, kNeverInlineAnnotation)) {
TRACE_INLINING(ISL_Print(" Bailout: NeverInline annotation\n"));
return false;
}
GrowableArray<Value*>* arguments = call_data->arguments;
const intptr_t constant_arguments = CountConstants(*arguments);
if (!ShouldWeInline(function,
function.optimized_instruction_count(),
function.optimized_call_site_count(),
constant_arguments)) {
TRACE_INLINING(ISL_Print(" Bailout: early heuristics with "
"code size: %" Pd ", "
"call sites: %" Pd ", "
"const args: %" Pd "\n",
function.optimized_instruction_count(),
function.optimized_call_site_count(),
constant_arguments));
PRINT_INLINING_TREE("Early heuristic",
&call_data->caller, &function, call_data->call);
return false;
}
// Abort if this is a recursive occurrence.
Definition* call = call_data->call;
// Added 'volatile' works around a possible GCC 4.9 compiler bug.
volatile bool is_recursive_call = IsCallRecursive(unoptimized_code, call);
if (is_recursive_call &&
inlining_recursion_depth_ >= FLAG_inlining_recursion_depth_threshold) {
TRACE_INLINING(ISL_Print(" Bailout: recursive function\n"));
PRINT_INLINING_TREE("Recursive function",
&call_data->caller, &function, call_data->call);
return false;
}
// Save and clear deopt id.
const intptr_t prev_deopt_id = isolate()->deopt_id();
isolate()->set_deopt_id(0);
// Install bailout jump.
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
// Parse the callee function.
bool in_cache;
ParsedFunction* parsed_function;
{
TimerScope timer(FLAG_compiler_stats,
&CompilerStats::graphinliner_parse_timer,
isolate());
parsed_function = GetParsedFunction(function, &in_cache);
}
// Load IC data for the callee.
ZoneGrowableArray<const ICData*>* ic_data_array =
new(Z) ZoneGrowableArray<const ICData*>();
function.RestoreICDataMap(ic_data_array);
// Build the callee graph.
InlineExitCollector* exit_collector =
new(Z) InlineExitCollector(caller_graph_, call);
FlowGraphBuilder builder(*parsed_function,
*ic_data_array,
exit_collector,
Isolate::kNoDeoptId);
builder.SetInitialBlockId(caller_graph_->max_block_id());
FlowGraph* callee_graph;
{
TimerScope timer(FLAG_compiler_stats,
&CompilerStats::graphinliner_build_timer,
isolate());
callee_graph = builder.BuildGraph();
}
// The parameter stubs are a copy of the actual arguments providing
// concrete information about the values, for example constant values,
// without linking between the caller and callee graphs.
// TODO(zerny): Put more information in the stubs, eg, type information.
ZoneGrowableArray<Definition*>* param_stubs =
new(Z) ZoneGrowableArray<Definition*>(
function.NumParameters());
// Create a parameter stub for each fixed positional parameter.
for (intptr_t i = 0; i < function.num_fixed_parameters(); ++i) {
param_stubs->Add(CreateParameterStub(i, (*arguments)[i], callee_graph));
}
// If the callee has optional parameters, rebuild the argument and stub
// arrays so that actual arguments are in one-to-one with the formal
// parameters.
if (function.HasOptionalParameters()) {
TRACE_INLINING(ISL_Print(" adjusting for optional parameters\n"));
if (!AdjustForOptionalParameters(*parsed_function,
argument_names,
arguments,
param_stubs,
callee_graph)) {
function.set_is_inlinable(false);
TRACE_INLINING(ISL_Print(" Bailout: optional arg mismatch\n"));
PRINT_INLINING_TREE("Optional arg mismatch",
&call_data->caller, &function, call_data->call);
return false;
}
}
// After treating optional parameters the actual/formal count must match.
ASSERT(arguments->length() == function.NumParameters());
ASSERT(param_stubs->length() == callee_graph->parameter_count());
// Update try-index of the callee graph.
BlockEntryInstr* call_block = call_data->call->GetBlock();
if (call_block->InsideTryBlock()) {
intptr_t try_index = call_block->try_index();
for (BlockIterator it = callee_graph->reverse_postorder_iterator();
!it.Done(); it.Advance()) {
BlockEntryInstr* block = it.Current();
block->set_try_index(try_index);
}
}
BlockScheduler block_scheduler(callee_graph);
block_scheduler.AssignEdgeWeights();
{
TimerScope timer(FLAG_compiler_stats,
&CompilerStats::graphinliner_ssa_timer,
isolate());
// Compute SSA on the callee graph, catching bailouts.
callee_graph->ComputeSSA(caller_graph_->max_virtual_register_number(),
param_stubs);
DEBUG_ASSERT(callee_graph->VerifyUseLists());
}
{
TimerScope timer(FLAG_compiler_stats,
&CompilerStats::graphinliner_opt_timer,
isolate());
// TODO(zerny): Do more optimization passes on the callee graph.
FlowGraphOptimizer optimizer(callee_graph);
optimizer.ApplyICData();
DEBUG_ASSERT(callee_graph->VerifyUseLists());
// Optimize (a << b) & c patterns, merge instructions. Must occur before
// 'SelectRepresentations' which inserts conversion nodes.
optimizer.TryOptimizePatterns();
DEBUG_ASSERT(callee_graph->VerifyUseLists());
}
if (FLAG_trace_inlining &&
(FLAG_print_flow_graph || FLAG_print_flow_graph_optimized)) {
ISL_Print("Callee graph for inlining %s\n",
function.ToFullyQualifiedCString());
FlowGraphPrinter printer(*callee_graph);
printer.PrintBlocks();
}
// Collect information about the call site and caller graph.
// TODO(zerny): Do this after CP and dead code elimination.
intptr_t constants_count = 0;
for (intptr_t i = 0; i < param_stubs->length(); ++i) {
if ((*param_stubs)[i]->IsConstant()) ++constants_count;
}
FlowGraphInliner::CollectGraphInfo(callee_graph);
const intptr_t size = function.optimized_instruction_count();
const intptr_t call_site_count = function.optimized_call_site_count();
function.set_optimized_instruction_count(size);
function.set_optimized_call_site_count(call_site_count);
// Use heuristics do decide if this call should be inlined.
if (!ShouldWeInline(function, size, call_site_count, constants_count)) {
// If size is larger than all thresholds, don't consider it again.
if ((size > FLAG_inlining_size_threshold) &&
(call_site_count > FLAG_inlining_callee_call_sites_threshold) &&
(size > FLAG_inlining_constant_arguments_min_size_threshold) &&
(size > FLAG_inlining_constant_arguments_max_size_threshold)) {
function.set_is_inlinable(false);
}
isolate()->set_deopt_id(prev_deopt_id);
TRACE_INLINING(ISL_Print(" Bailout: heuristics with "
"code size: %" Pd ", "
"call sites: %" Pd ", "
"const args: %" Pd "\n",
size,
call_site_count,
constants_count));
PRINT_INLINING_TREE("Heuristic fail",
&call_data->caller, &function, call_data->call);
return false;
}
// Inline dispatcher methods regardless of the current depth.
const intptr_t depth =
(function.IsInvokeFieldDispatcher() ||
function.IsNoSuchMethodDispatcher()) ? 0 : inlining_depth_;
collected_call_sites_->FindCallSites(callee_graph, depth, &inlined_info_);
// Add the function to the cache.
if (!in_cache) {
function_cache_.Add(parsed_function);
}
// Build succeeded so we restore the bailout jump.
inlined_ = true;
inlined_size_ += size;
if (is_recursive_call) {
inlined_recursive_call_ = true;
}
isolate()->set_deopt_id(prev_deopt_id);
call_data->callee_graph = callee_graph;
call_data->parameter_stubs = param_stubs;
call_data->exit_collector = exit_collector;
// When inlined, we add the guarded fields of the callee to the caller's
// list of guarded fields.
for (intptr_t i = 0; i < callee_graph->guarded_fields()->length(); ++i) {
FlowGraph::AddToGuardedFields(caller_graph_->guarded_fields(),
(*callee_graph->guarded_fields())[i]);
}
// When inlined, we add the deferred prefixes of the callee to the
// caller's list of deferred prefixes.
caller_graph()->AddToDeferredPrefixes(callee_graph->deferred_prefixes());
FlowGraphInliner::SetInliningId(callee_graph,
inliner_->NextInlineId(callee_graph->function(),
call_data->caller_inlining_id_));
// We allocate a ZoneHandle for the unoptimized code so that it cannot be
// disconnected from its function during the rest of compilation.
Code::ZoneHandle(unoptimized_code.raw());
TRACE_INLINING(ISL_Print(" Success\n"));
PRINT_INLINING_TREE(NULL,
&call_data->caller, &function, call);
return true;
} else {
Error& error = Error::Handle();
error = isolate()->object_store()->sticky_error();
isolate()->object_store()->clear_sticky_error();
isolate()->set_deopt_id(prev_deopt_id);
TRACE_INLINING(ISL_Print(" Bailout: %s\n", error.ToErrorCString()));
PRINT_INLINING_TREE("Bailout",
&call_data->caller, &function, call);
return false;
}
}
void PrintInlinedInfo(const Function& top) {
if (inlined_info_.length() > 0) {
ISL_Print("Inlining into: '%s' growth: %f (%" Pd " -> %" Pd ")\n",
top.ToFullyQualifiedCString(),
GrowthFactor(),
initial_size_,
inlined_size_);
PrintInlinedInfoFor(top, 1);
}
}
private:
friend class PolymorphicInliner;
static bool Contains(const GrowableArray<intptr_t>& a, intptr_t deopt_id) {
for (intptr_t i = 0; i < a.length(); i++) {
if (a[i] == deopt_id) return true;
}
return false;
}
void PrintInlinedInfoFor(const Function& caller, intptr_t depth) {
// Prevent duplicate printing as inlined_info aggregates all inlinining.
GrowableArray<intptr_t> call_instructions_printed;
// Print those that were inlined.
for (intptr_t i = 0; i < inlined_info_.length(); i++) {
const InlinedInfo& info = inlined_info_[i];
if (info.bailout_reason != NULL) {
continue;
}
if ((info.inlined_depth == depth) &&
(info.caller->raw() == caller.raw()) &&
!Contains(call_instructions_printed, info.call_instr->GetDeoptId())) {
for (int t = 0; t < depth; t++) {
ISL_Print(" ");
}
ISL_Print("%" Pd " %s\n",
info.call_instr->GetDeoptId(),
info.inlined->ToQualifiedCString());
PrintInlinedInfoFor(*info.inlined, depth + 1);
call_instructions_printed.Add(info.call_instr->GetDeoptId());
}
}
call_instructions_printed.Clear();
// Print those that were not inlined.
for (intptr_t i = 0; i < inlined_info_.length(); i++) {
const InlinedInfo& info = inlined_info_[i];
if (info.bailout_reason == NULL) {
continue;
}
if ((info.inlined_depth == depth) &&
(info.caller->raw() == caller.raw()) &&
!Contains(call_instructions_printed, info.call_instr->GetDeoptId())) {
for (int t = 0; t < depth; t++) {
ISL_Print(" ");
}
ISL_Print("NO %" Pd " %s - %s\n",
info.call_instr->GetDeoptId(),
info.inlined->ToQualifiedCString(),
info.bailout_reason);
call_instructions_printed.Add(info.call_instr->GetDeoptId());
}
}
}
void InlineCall(InlinedCallData* call_data) {
TimerScope timer(FLAG_compiler_stats,
&CompilerStats::graphinliner_subst_timer,
Isolate::Current());
FlowGraph* callee_graph = call_data->callee_graph;
TargetEntryInstr* callee_entry =
callee_graph->graph_entry()->normal_entry();
// Plug result in the caller graph.
InlineExitCollector* exit_collector = call_data->exit_collector;
exit_collector->PrepareGraphs(callee_graph);
exit_collector->ReplaceCall(callee_entry);
// Replace each stub with the actual argument or the caller's constant.
// Nulls denote optional parameters for which no actual was given.
GrowableArray<Value*>* arguments = call_data->arguments;
for (intptr_t i = 0; i < arguments->length(); ++i) {
Definition* stub = (*call_data->parameter_stubs)[i];
Value* actual = (*arguments)[i];
if (actual != NULL) stub->ReplaceUsesWith(actual->definition());
}
// Remove push arguments of the call.
Definition* call = call_data->call;
for (intptr_t i = 0; i < call->ArgumentCount(); ++i) {
PushArgumentInstr* push = call->PushArgumentAt(i);
push->ReplaceUsesWith(push->value()->definition());
push->RemoveFromGraph();
}
// Replace remaining constants with uses by constants in the caller's
// initial definitions.
GrowableArray<Definition*>* defns =
callee_graph->graph_entry()->initial_definitions();
for (intptr_t i = 0; i < defns->length(); ++i) {
ConstantInstr* constant = (*defns)[i]->AsConstant();
if ((constant != NULL) && constant->HasUses()) {
constant->ReplaceUsesWith(
caller_graph_->GetConstant(constant->value()));
}
CurrentContextInstr* context = (*defns)[i]->AsCurrentContext();
if ((context != NULL) && context->HasUses()) {
ASSERT(call->IsClosureCall());
LoadFieldInstr* context_load = new(Z) LoadFieldInstr(
new Value((*arguments)[0]->definition()),
Closure::context_offset(),
AbstractType::ZoneHandle(isolate(), AbstractType::null()),
call_data->call->token_pos());
context_load->set_is_immutable(true);
context_load->set_ssa_temp_index(
caller_graph_->alloc_ssa_temp_index());
context_load->InsertBefore(callee_entry->next());
context->ReplaceUsesWith(context_load);
}
}
// Check that inlining maintains use lists.
DEBUG_ASSERT(!FLAG_verify_compiler || caller_graph_->VerifyUseLists());
}
static intptr_t CountConstants(const GrowableArray<Value*>& arguments) {
intptr_t count = 0;
for (intptr_t i = 0; i < arguments.length(); i++) {
if (arguments[i]->BindsToConstant()) count++;
}
return count;
}
// Parse a function reusing the cache if possible.
ParsedFunction* GetParsedFunction(const Function& function, bool* in_cache) {
// TODO(zerny): Use a hash map for the cache.
for (intptr_t i = 0; i < function_cache_.length(); ++i) {
ParsedFunction* parsed_function = function_cache_[i];
if (parsed_function->function().raw() == function.raw()) {
*in_cache = true;
return parsed_function;
}
}
*in_cache = false;
ParsedFunction* parsed_function =
new(Z) ParsedFunction(thread(), function);
Parser::ParseFunction(parsed_function);
parsed_function->AllocateVariables();
return parsed_function;
}
// Include special handling for List. factory: inlining it is not helpful
// if the incoming argument is a non-constant value.
// TODO(srdjan): Fix inlining of List. factory.
void InlineStaticCalls() {
const GrowableArray<CallSites::StaticCallInfo>& call_info =
inlining_call_sites_->static_calls();
TRACE_INLINING(ISL_Print(" Static Calls (%" Pd ")\n", call_info.length()));
for (intptr_t call_idx = 0; call_idx < call_info.length(); ++call_idx) {
StaticCallInstr* call = call_info[call_idx].call;
if (call->function().name() == Symbols::ListFactory().raw()) {
// Inline only if no arguments or a constant was passed.
ASSERT(call->function().NumImplicitParameters() == 1);
ASSERT(call->ArgumentCount() <= 2);
// Arg 0: Instantiator type arguments.
// Arg 1: Length (optional).
if ((call->ArgumentCount() == 2) &&
(!call->PushArgumentAt(1)->value()->BindsToConstant())) {
// Do not inline since a non-constant argument was passed.
continue;
}
}
const Function& target = call->function();
if (!inliner_->AlwaysInline(target) &&
(call_info[call_idx].ratio * 100) < FLAG_inlining_hotness) {
TRACE_INLINING(ISL_Print(
" => %s (deopt count %d)\n Bailout: cold %f\n",
target.ToCString(),
target.deoptimization_counter(),
call_info[call_idx].ratio));
PRINT_INLINING_TREE("Too cold",
&call_info[call_idx].caller(), &call->function(), call);
continue;
}
GrowableArray<Value*> arguments(call->ArgumentCount());
for (int i = 0; i < call->ArgumentCount(); ++i) {
arguments.Add(call->PushArgumentAt(i)->value());
}
InlinedCallData call_data(
call, &arguments, call_info[call_idx].caller(),
call_info[call_idx].caller_graph->inlining_id());
if (TryInlining(call->function(), call->argument_names(), &call_data)) {
InlineCall(&call_data);
}
}
}
void InlineClosureCalls() {
const GrowableArray<CallSites::ClosureCallInfo>& call_info =
inlining_call_sites_->closure_calls();
TRACE_INLINING(ISL_Print(" Closure Calls (%" Pd ")\n",
call_info.length()));
for (intptr_t call_idx = 0; call_idx < call_info.length(); ++call_idx) {
ClosureCallInstr* call = call_info[call_idx].call;
// Find the closure of the callee.
ASSERT(call->ArgumentCount() > 0);
Function& target = Function::ZoneHandle();
AllocateObjectInstr* alloc =
call->ArgumentAt(0)->OriginalDefinition()->AsAllocateObject();
if ((alloc != NULL) && !alloc->closure_function().IsNull()) {
target ^= alloc->closure_function().raw();
ASSERT(target.signature_class() == alloc->cls().raw());
}
ConstantInstr* constant =
call->ArgumentAt(0)->OriginalDefinition()->AsConstant();
if ((constant != NULL) &&
constant->value().IsInstance() &&
Instance::Cast(constant->value()).IsClosure()) {
target ^= Closure::function(Instance::Cast(constant->value()));
}
if (target.IsNull()) {
TRACE_INLINING(ISL_Print(" Bailout: non-closure operator\n"));
continue;
}
GrowableArray<Value*> arguments(call->ArgumentCount());
for (int i = 0; i < call->ArgumentCount(); ++i) {
arguments.Add(call->PushArgumentAt(i)->value());
}
InlinedCallData call_data(
call, &arguments, call_info[call_idx].caller(),
call_info[call_idx].caller_graph->inlining_id());
if (TryInlining(target,
call->argument_names(),
&call_data)) {
InlineCall(&call_data);
}
}
}
void InlineInstanceCalls() {
const GrowableArray<CallSites::InstanceCallInfo>& call_info =
inlining_call_sites_->instance_calls();
TRACE_INLINING(ISL_Print(" Polymorphic Instance Calls (%" Pd ")\n",
call_info.length()));
for (intptr_t call_idx = 0; call_idx < call_info.length(); ++call_idx) {
PolymorphicInstanceCallInstr* call = call_info[call_idx].call;
if (call->with_checks()) {
const Function& cl = call_info[call_idx].caller();
intptr_t caller_inlining_id =
call_info[call_idx].caller_graph->inlining_id();
PolymorphicInliner inliner(this, call, cl, caller_inlining_id);
inliner.Inline();
continue;
}
const ICData& ic_data = call->ic_data();
const Function& target = Function::ZoneHandle(ic_data.GetTargetAt(0));
if (!inliner_->AlwaysInline(target) &&
(call_info[call_idx].ratio * 100) < FLAG_inlining_hotness) {
TRACE_INLINING(ISL_Print(
" => %s (deopt count %d)\n Bailout: cold %f\n",
target.ToCString(),
target.deoptimization_counter(),
call_info[call_idx].ratio));
PRINT_INLINING_TREE("Too cold",
&call_info[call_idx].caller(), &target, call);
continue;
}
GrowableArray<Value*> arguments(call->ArgumentCount());
for (int arg_i = 0; arg_i < call->ArgumentCount(); ++arg_i) {
arguments.Add(call->PushArgumentAt(arg_i)->value());
}
InlinedCallData call_data(
call, &arguments, call_info[call_idx].caller(),
call_info[call_idx].caller_graph->inlining_id());
if (TryInlining(target,
call->instance_call()->argument_names(),
&call_data)) {
InlineCall(&call_data);
}
}
}
bool AdjustForOptionalParameters(const ParsedFunction& parsed_function,
const Array& argument_names,
GrowableArray<Value*>* arguments,
ZoneGrowableArray<Definition*>* param_stubs,
FlowGraph* callee_graph) {
const Function& function = parsed_function.function();
// The language and this code does not support both optional positional
// and optional named parameters for the same function.
ASSERT(!function.HasOptionalPositionalParameters() ||
!function.HasOptionalNamedParameters());
intptr_t arg_count = arguments->length();
intptr_t param_count = function.NumParameters();
intptr_t fixed_param_count = function.num_fixed_parameters();
ASSERT(fixed_param_count <= arg_count);
ASSERT(arg_count <= param_count);
if (function.HasOptionalPositionalParameters()) {
// Create a stub for each optional positional parameters with an actual.
for (intptr_t i = fixed_param_count; i < arg_count; ++i) {
param_stubs->Add(CreateParameterStub(i, (*arguments)[i], callee_graph));
}
ASSERT(function.NumOptionalPositionalParameters() ==
(param_count - fixed_param_count));
// For each optional positional parameter without an actual, add its
// default value.
for (intptr_t i = arg_count; i < param_count; ++i) {
const Object& object =
Object::ZoneHandle(
parsed_function.default_parameter_values().At(
i - fixed_param_count));
ConstantInstr* constant = new(Z) ConstantInstr(object);
arguments->Add(NULL);
param_stubs->Add(constant);
}
return true;
}
ASSERT(function.HasOptionalNamedParameters());
// Passed arguments must match fixed parameters plus named arguments.
intptr_t argument_names_count =
(argument_names.IsNull()) ? 0 : argument_names.Length();
ASSERT(arg_count == (fixed_param_count + argument_names_count));
// Fast path when no optional named parameters are given.
if (argument_names_count == 0) {
for (intptr_t i = 0; i < param_count - fixed_param_count; ++i) {
arguments->Add(NULL);
param_stubs->Add(GetDefaultValue(i, parsed_function));
}
return true;
}
// Otherwise, build a collection of name/argument pairs.
GrowableArray<NamedArgument> named_args(argument_names_count);
for (intptr_t i = 0; i < argument_names.Length(); ++i) {
String& arg_name = String::Handle(Isolate::Current());
arg_name ^= argument_names.At(i);
named_args.Add(
NamedArgument(&arg_name, (*arguments)[i + fixed_param_count]));
}
// Truncate the arguments array to just fixed parameters.
arguments->TruncateTo(fixed_param_count);
// For each optional named parameter, add the actual argument or its
// default if no argument is passed.
intptr_t match_count = 0;
for (intptr_t i = fixed_param_count; i < param_count; ++i) {
String& param_name = String::Handle(function.ParameterNameAt(i));
// Search for and add the named argument.
Value* arg = NULL;
for (intptr_t j = 0; j < named_args.length(); ++j) {
if (param_name.Equals(*named_args[j].name)) {
arg = named_args[j].value;
match_count++;
break;
}
}
arguments->Add(arg);
// Create a stub for the argument or use the parameter's default value.
if (arg != NULL) {
param_stubs->Add(CreateParameterStub(i, arg, callee_graph));
} else {
param_stubs->Add(
GetDefaultValue(i - fixed_param_count, parsed_function));
}
}
return argument_names_count == match_count;
}
FlowGraphInliner* inliner_;
FlowGraph* caller_graph_;
bool inlined_;
const intptr_t initial_size_;
intptr_t inlined_size_;
bool inlined_recursive_call_;
intptr_t inlining_depth_;
intptr_t inlining_recursion_depth_;
CallSites* collected_call_sites_;
CallSites* inlining_call_sites_;
GrowableArray<ParsedFunction*> function_cache_;
GrowableArray<InlinedInfo> inlined_info_;
DISALLOW_COPY_AND_ASSIGN(CallSiteInliner);
};
PolymorphicInliner::PolymorphicInliner(CallSiteInliner* owner,
PolymorphicInstanceCallInstr* call,
const Function& caller_function,
intptr_t caller_inlining_id)
: owner_(owner),
call_(call),
num_variants_(call->ic_data().NumberOfChecks()),
variants_(num_variants_),
inlined_variants_(num_variants_),
non_inlined_variants_(num_variants_),
inlined_entries_(num_variants_),
exit_collector_(new(Z)
InlineExitCollector(owner->caller_graph(), call)),
caller_function_(caller_function),
caller_inlining_id_(caller_inlining_id) {
}
Isolate* PolymorphicInliner::isolate() const {
return owner_->caller_graph()->isolate();
}
Zone* PolymorphicInliner::zone() const {
return owner_->caller_graph()->zone();
}
// Inlined bodies are shared if two different class ids have the same
// inlined target. This sharing is represented by using three different
// types of entries in the inlined_entries_ array:
//
// * GraphEntry: the inlined body is not shared.
//
// * TargetEntry: the inlined body is shared and this is the first variant.
//
// * JoinEntry: the inlined body is shared and this is a subsequent variant.
bool PolymorphicInliner::CheckInlinedDuplicate(const Function& target) {
for (intptr_t i = 0; i < inlined_variants_.length(); ++i) {
if ((target.raw() == inlined_variants_[i].target->raw()) &&
!MethodRecognizer::PolymorphicTarget(target)) {
// The call target is shared with a previous inlined variant. Share
// the graph. This requires a join block at the entry, and edge-split
// form requires a target for each branch.
//
// Represent the sharing by recording a fresh target for the first
// variant and the shared join for all later variants.
if (inlined_entries_[i]->IsGraphEntry()) {
// Convert the old target entry to a new join entry.
TargetEntryInstr* old_target =
inlined_entries_[i]->AsGraphEntry()->normal_entry();
// Unuse all inputs in the the old graph entry since it is not part of
// the graph anymore. A new target be created instead.
inlined_entries_[i]->AsGraphEntry()->UnuseAllInputs();
JoinEntryInstr* new_join =
BranchSimplifier::ToJoinEntry(isolate(), old_target);
old_target->ReplaceAsPredecessorWith(new_join);
for (intptr_t j = 0; j < old_target->dominated_blocks().length(); ++j) {
BlockEntryInstr* block = old_target->dominated_blocks()[j];
new_join->AddDominatedBlock(block);
}
// Create a new target with the join as unconditional successor.
TargetEntryInstr* new_target =
new TargetEntryInstr(owner_->caller_graph()->allocate_block_id(),
old_target->try_index());
new_target->InheritDeoptTarget(isolate(), new_join);
GotoInstr* new_goto = new(Z) GotoInstr(new_join);
new_goto->InheritDeoptTarget(isolate(), new_join);
new_target->LinkTo(new_goto);
new_target->set_last_instruction(new_goto);
new_join->predecessors_.Add(new_target);
// Record the new target for the first variant.
inlined_entries_[i] = new_target;
}
ASSERT(inlined_entries_[i]->IsTargetEntry());
// Record the shared join for this variant.
BlockEntryInstr* join =
inlined_entries_[i]->last_instruction()->SuccessorAt(0);
ASSERT(join->IsJoinEntry());
inlined_entries_.Add(join);
return true;
}
}
return false;
}
bool PolymorphicInliner::CheckNonInlinedDuplicate(const Function& target) {
for (intptr_t i = 0; i < non_inlined_variants_.length(); ++i) {
if (target.raw() == non_inlined_variants_[i].target->raw()) {
return true;
}
}
return false;
}
bool PolymorphicInliner::TryInliningPoly(intptr_t receiver_cid,
const Function& target) {
if (TryInlineRecognizedMethod(receiver_cid, target)) {
owner_->inlined_ = true;
return true;
}
GrowableArray<Value*> arguments(call_->ArgumentCount());
for (int i = 0; i < call_->ArgumentCount(); ++i) {
arguments.Add(call_->PushArgumentAt(i)->value());
}
InlinedCallData call_data(call_, &arguments,
caller_function_,
caller_inlining_id_);
if (!owner_->TryInlining(target,
call_->instance_call()->argument_names(),
&call_data)) {
return false;
}
FlowGraph* callee_graph = call_data.callee_graph;
call_data.exit_collector->PrepareGraphs(callee_graph);
inlined_entries_.Add(callee_graph->graph_entry());
exit_collector_->Union(call_data.exit_collector);
// Replace parameter stubs and constants. Replace the receiver argument
// with a redefinition to prevent code from the inlined body from being
// hoisted above the inlined entry.
ASSERT(arguments.length() > 0);
Value* actual = arguments[0];
RedefinitionInstr* redefinition = new(Z)
RedefinitionInstr(actual->Copy(isolate()));
redefinition->set_ssa_temp_index(
owner_->caller_graph()->alloc_ssa_temp_index());
redefinition->UpdateType(CompileType::FromCid(receiver_cid));
redefinition->InsertAfter(callee_graph->graph_entry()->normal_entry());
Definition* stub = (*call_data.parameter_stubs)[0];
stub->ReplaceUsesWith(redefinition);
for (intptr_t i = 1; i < arguments.length(); ++i) {
actual = arguments[i];
if (actual != NULL) {
stub = (*call_data.parameter_stubs)[i];
stub->ReplaceUsesWith(actual->definition());
}
}
GrowableArray<Definition*>* defns =
callee_graph->graph_entry()->initial_definitions();
for (intptr_t i = 0; i < defns->length(); ++i) {
ConstantInstr* constant = (*defns)[i]->AsConstant();
if ((constant != NULL) && constant->HasUses()) {
constant->ReplaceUsesWith(
owner_->caller_graph()->GetConstant(constant->value()));
}
CurrentContextInstr* context = (*defns)[i]->AsCurrentContext();
if ((context != NULL) && context->HasUses()) {
ASSERT(call_data.call->IsClosureCall());
LoadFieldInstr* context_load = new(Z) LoadFieldInstr(
new Value(redefinition),
Closure::context_offset(),
AbstractType::ZoneHandle(isolate(), AbstractType::null()),
call_data.call->token_pos());
context_load->set_is_immutable(true);
context_load->set_ssa_temp_index(
owner_->caller_graph()->alloc_ssa_temp_index());
context_load->InsertAfter(redefinition);
context->ReplaceUsesWith(context_load);
}
}
return true;
}
static Instruction* AppendInstruction(Instruction* first,
Instruction* second) {
for (intptr_t i = second->InputCount() - 1; i >= 0; --i) {
Value* input = second->InputAt(i);
input->definition()->AddInputUse(input);
}
first->LinkTo(second);
return second;
}
bool PolymorphicInliner::TryInlineRecognizedMethod(intptr_t receiver_cid,
const Function& target) {
FlowGraphOptimizer optimizer(owner_->caller_graph());
TargetEntryInstr* entry;
Definition* last;
// Replace the receiver argument with a redefinition to prevent code from
// the inlined body from being hoisted above the inlined entry.
GrowableArray<Definition*> arguments(call_->ArgumentCount());
Definition* receiver = call_->ArgumentAt(0);
RedefinitionInstr* redefinition =
new(Z) RedefinitionInstr(new(Z) Value(receiver));
redefinition->set_ssa_temp_index(
owner_->caller_graph()->alloc_ssa_temp_index());
if (optimizer.TryInlineRecognizedMethod(receiver_cid,
target,
call_,
redefinition,
call_->instance_call()->token_pos(),
*call_->instance_call()->ic_data(),
&entry, &last)) {
// Create a graph fragment.
redefinition->InsertAfter(entry);
InlineExitCollector* exit_collector =
new(Z) InlineExitCollector(owner_->caller_graph(), call_);
ReturnInstr* result =
new(Z) ReturnInstr(call_->instance_call()->token_pos(),
new(Z) Value(last));
owner_->caller_graph()->AppendTo(
last,
result,
call_->env(), // Return can become deoptimization target.
FlowGraph::kEffect);
entry->set_last_instruction(result);
exit_collector->AddExit(result);
ParsedFunction* temp_parsed_function =
new ParsedFunction(Thread::Current(), target);
GraphEntryInstr* graph_entry =
new(Z) GraphEntryInstr(*temp_parsed_function,
entry,
Isolate::kNoDeoptId); // No OSR id.
// Update polymorphic inliner state.
inlined_entries_.Add(graph_entry);
exit_collector_->Union(exit_collector);
return true;
}
return false;
}
// Build a DAG to dispatch to the inlined function bodies. Load the class
// id of the receiver and make explicit comparisons for each inlined body,
// in frequency order. If all variants are inlined, the entry to the last
// inlined body is guarded by a CheckClassId instruction which can deopt.
// If not all variants are inlined, we add a PolymorphicInstanceCall
// instruction to handle the non-inlined variants.
TargetEntryInstr* PolymorphicInliner::BuildDecisionGraph() {
// Start with a fresh target entry.
TargetEntryInstr* entry =
new(Z) TargetEntryInstr(
owner_->caller_graph()->allocate_block_id(),
call_->GetBlock()->try_index());
entry->InheritDeoptTarget(isolate(), call_);
// This function uses a cursor (a pointer to the 'current' instruction) to
// build the graph. The next instruction will be inserted after the
// cursor.
TargetEntryInstr* current_block = entry;
Instruction* cursor = entry;
Definition* receiver = call_->ArgumentAt(0);
// There are at least two variants including non-inlined ones, so we have
// at least one branch on the class id.
LoadClassIdInstr* load_cid =
new(Z) LoadClassIdInstr(new(Z) Value(receiver));
load_cid->set_ssa_temp_index(owner_->caller_graph()->alloc_ssa_temp_index());
cursor = AppendInstruction(cursor, load_cid);
for (intptr_t i = 0; i < inlined_variants_.length(); ++i) {
// 1. Guard the body with a class id check.
if ((i == (inlined_variants_.length() - 1)) &&
non_inlined_variants_.is_empty()) {
// If it is the last variant use a check class id instruction which can
// deoptimize, followed unconditionally by the body.
RedefinitionInstr* cid_redefinition =
new RedefinitionInstr(new(Z) Value(load_cid));
cid_redefinition->set_ssa_temp_index(
owner_->caller_graph()->alloc_ssa_temp_index());
cursor = AppendInstruction(cursor, cid_redefinition);
CheckClassIdInstr* check_class_id = new(Z) CheckClassIdInstr(
new(Z) Value(cid_redefinition),
inlined_variants_[i].cid,
call_->deopt_id());
check_class_id->InheritDeoptTarget(isolate(), call_);
cursor = AppendInstruction(cursor, check_class_id);
// The next instruction is the first instruction of the inlined body.
// Handle the two possible cases (unshared and shared subsequent
// predecessors) separately.
BlockEntryInstr* callee_entry = inlined_entries_[i];
if (callee_entry->IsGraphEntry()) {
// Unshared. Graft the normal entry on after the check class
// instruction.
TargetEntryInstr* target =
callee_entry->AsGraphEntry()->normal_entry();
cursor->LinkTo(target->next());
target->ReplaceAsPredecessorWith(current_block);
// Unuse all inputs of the graph entry and the normal entry. They are
// not in the graph anymore.
callee_entry->UnuseAllInputs();
target->UnuseAllInputs();
// All blocks that were dominated by the normal entry are now
// dominated by the current block.
for (intptr_t j = 0;
j < target->dominated_blocks().length();
++j) {
BlockEntryInstr* block = target->dominated_blocks()[j];
current_block->AddDominatedBlock(block);
}
} else if (callee_entry->IsJoinEntry()) {
// Shared inlined body and this is a subsequent entry. We have
// already constructed a join and set its dominator. Add a jump to
// the join.
JoinEntryInstr* join = callee_entry->AsJoinEntry();
ASSERT(join->dominator() != NULL);
GotoInstr* goto_join = new GotoInstr(join);
goto_join->InheritDeoptTarget(isolate(), join);
cursor->LinkTo(goto_join);
current_block->set_last_instruction(goto_join);
} else {
// There is no possibility of a TargetEntry (the first entry to a
// shared inlined body) because this is the last inlined entry.
UNREACHABLE();
}
cursor = NULL;
} else {
// For all variants except the last, use a branch on the loaded class
// id.
const Smi& cid = Smi::ZoneHandle(Smi::New(inlined_variants_[i].cid));
ConstantInstr* cid_constant = new ConstantInstr(cid);
cid_constant->set_ssa_temp_index(
owner_->caller_graph()->alloc_ssa_temp_index());
StrictCompareInstr* compare =
new StrictCompareInstr(call_->instance_call()->token_pos(),
Token::kEQ_STRICT,
new Value(load_cid),
new Value(cid_constant),
false); // No number check.
BranchInstr* branch = new BranchInstr(compare);
branch->InheritDeoptTarget(isolate(), call_);
AppendInstruction(AppendInstruction(cursor, cid_constant), branch);
current_block->set_last_instruction(branch);
cursor = NULL;
// 2. Handle a match by linking to the inlined body. There are three
// cases (unshared, shared first predecessor, and shared subsequent
// predecessors).
BlockEntryInstr* callee_entry = inlined_entries_[i];
TargetEntryInstr* true_target = NULL;
if (callee_entry->IsGraphEntry()) {
// Unshared.
true_target = callee_entry->AsGraphEntry()->normal_entry();
// Unuse all inputs of the graph entry. It is not in the graph anymore.
callee_entry->UnuseAllInputs();
} else if (callee_entry->IsTargetEntry()) {
// Shared inlined body and this is the first entry. We have already
// constructed a join and this target jumps to it.
true_target = callee_entry->AsTargetEntry();
BlockEntryInstr* join =
true_target->last_instruction()->SuccessorAt(0);
current_block->AddDominatedBlock(join);
} else {
// Shared inlined body and this is a subsequent entry. We have
// already constructed a join. We need a fresh target that jumps to
// the join.
JoinEntryInstr* join = callee_entry->AsJoinEntry();
ASSERT(join != NULL);
ASSERT(join->dominator() != NULL);
true_target =
new TargetEntryInstr(owner_->caller_graph()->allocate_block_id(),
call_->GetBlock()->try_index());
true_target->InheritDeoptTarget(isolate(), join);
GotoInstr* goto_join = new GotoInstr(join);
goto_join->InheritDeoptTarget(isolate(), join);
true_target->LinkTo(goto_join);
true_target->set_last_instruction(goto_join);
}
*branch->true_successor_address() = true_target;
current_block->AddDominatedBlock(true_target);
// 3. Prepare to handle a match failure on the next iteration or the
// fall-through code below for non-inlined variants.
TargetEntryInstr* false_target =
new TargetEntryInstr(owner_->caller_graph()->allocate_block_id(),
call_->GetBlock()->try_index());
false_target->InheritDeoptTarget(isolate(), call_);
*branch->false_successor_address() = false_target;
current_block->AddDominatedBlock(false_target);
cursor = current_block = false_target;
}
}
// Handle any non-inlined variants.
if (!non_inlined_variants_.is_empty()) {
// Move push arguments of the call.
for (intptr_t i = 0; i < call_->ArgumentCount(); ++i) {
PushArgumentInstr* push = call_->PushArgumentAt(i);
push->ReplaceUsesWith(push->value()->definition());
push->previous()->LinkTo(push->next());
cursor->LinkTo(push);
cursor = push;
}
const ICData& old_checks = call_->ic_data();
const ICData& new_checks = ICData::ZoneHandle(
ICData::New(Function::Handle(old_checks.owner()),
String::Handle(old_checks.target_name()),
Array::Handle(old_checks.arguments_descriptor()),
old_checks.deopt_id(),
1)); // Number of args tested.
for (intptr_t i = 0; i < non_inlined_variants_.length(); ++i) {
new_checks.AddReceiverCheck(non_inlined_variants_[i].cid,
*non_inlined_variants_[i].target,
non_inlined_variants_[i].count);
}
PolymorphicInstanceCallInstr* fallback_call =
new PolymorphicInstanceCallInstr(call_->instance_call(),
new_checks,
true); // With checks.
fallback_call->set_ssa_temp_index(
owner_->caller_graph()->alloc_ssa_temp_index());
fallback_call->InheritDeoptTarget(isolate(), call_);
ReturnInstr* fallback_return =
new ReturnInstr(call_->instance_call()->token_pos(),
new Value(fallback_call));
fallback_return->InheritDeoptTargetAfter(
owner_->caller_graph(),
call_,
fallback_call);
AppendInstruction(AppendInstruction(cursor, fallback_call),
fallback_return);
exit_collector_->AddExit(fallback_return);
cursor = NULL;
} else {
// Remove push arguments of the call.
for (intptr_t i = 0; i < call_->ArgumentCount(); ++i) {
PushArgumentInstr* push = call_->PushArgumentAt(i);
push->ReplaceUsesWith(push->value()->definition());
push->RemoveFromGraph();
}
}
return entry;
}
void PolymorphicInliner::Inline() {
// Consider the polymorphic variants in order by frequency.
FlowGraphCompiler::SortICDataByCount(call_->ic_data(),
&variants_,
/* drop_smi = */ false);
for (intptr_t var_idx = 0; var_idx < variants_.length(); ++var_idx) {
const Function& target = *variants_[var_idx].target;
const intptr_t receiver_cid = variants_[var_idx].cid;
// First check if this is the same target as an earlier inlined variant.
if (CheckInlinedDuplicate(target)) {
inlined_variants_.Add(variants_[var_idx]);
continue;
}
// Also check if this is the same target as an earlier non-inlined
// variant. If so and since inlining decisions are costly, do not try
// to inline this variant.
if (CheckNonInlinedDuplicate(target)) {
non_inlined_variants_.Add(variants_[var_idx]);
continue;
}
// Make an inlining decision.
if (TryInliningPoly(receiver_cid, target)) {
inlined_variants_.Add(variants_[var_idx]);
} else {
non_inlined_variants_.Add(variants_[var_idx]);
}
}
// If there are no inlined variants, leave the call in place.
if (inlined_variants_.is_empty()) return;
// Now build a decision tree (a DAG because of shared inline variants) and
// inline it at the call site.
TargetEntryInstr* entry = BuildDecisionGraph();
exit_collector_->ReplaceCall(entry);
}
static uint16_t ClampUint16(intptr_t v) {
return (v > 0xFFFF) ? 0xFFFF : static_cast<uint16_t>(v);
}
static bool ShouldTraceInlining(FlowGraph* flow_graph) {
const Function& top = flow_graph->parsed_function().function();
return FLAG_trace_inlining && FlowGraphPrinter::ShouldPrint(top);
}
FlowGraphInliner::FlowGraphInliner(
FlowGraph* flow_graph,
GrowableArray<const Function*>* inline_id_to_function,
GrowableArray<intptr_t>* caller_inline_id)
: flow_graph_(flow_graph),
inline_id_to_function_(inline_id_to_function),
caller_inline_id_(caller_inline_id),
trace_inlining_(ShouldTraceInlining(flow_graph)) {
}
void FlowGraphInliner::CollectGraphInfo(FlowGraph* flow_graph, bool force) {
const Function& function = flow_graph->function();
if (force || (function.optimized_instruction_count() == 0)) {
GraphInfoCollector info;
info.Collect(*flow_graph);
function.set_optimized_instruction_count(
ClampUint16(info.instruction_count()));
function.set_optimized_call_site_count(ClampUint16(info.call_site_count()));
}
}
// TODO(srdjan): This is only needed when disassembling and/or profiling.
// Sets inlining id for all instructions of this flow-graph, as well for the
// FlowGraph itself.
void FlowGraphInliner::SetInliningId(FlowGraph* flow_graph,
intptr_t inlining_id) {
ASSERT(flow_graph->inlining_id() < 0);
flow_graph->set_inlining_id(inlining_id);
for (BlockIterator block_it = flow_graph->postorder_iterator();
!block_it.Done();
block_it.Advance()) {
for (ForwardInstructionIterator it(block_it.Current());
!it.Done();
it.Advance()) {
Instruction* current = it.Current();
// Do not overwrite owner function.
ASSERT(!current->has_inlining_id());
current->set_inlining_id(inlining_id);
}
}
}
bool FlowGraphInliner::AlwaysInline(const Function& function) {
const char* kAlwaysInlineAnnotation = "AlwaysInline";
if (FLAG_enable_inlining_annotations &&
HasAnnotation(function, kAlwaysInlineAnnotation)) {
TRACE_INLINING(ISL_Print("AlwaysInline annotation for %s\n",
function.ToCString()));
return true;
}
if (function.IsImplicitGetterFunction() || function.IsGetterFunction() ||
function.IsImplicitSetterFunction() || function.IsSetterFunction()) {
const intptr_t count = function.optimized_instruction_count();
if ((count != 0) && (count < FLAG_inline_getters_setters_smaller_than)) {
return true;
}
}
return MethodRecognizer::AlwaysInline(function);
}
void FlowGraphInliner::Inline() {
// Collect graph info and store it on the function.
// We might later use it for an early bailout from the inlining.
CollectGraphInfo(flow_graph_);
const Function& top = flow_graph_->function();
if ((FLAG_inlining_filter != NULL) &&
(strstr(top.ToFullyQualifiedCString(), FLAG_inlining_filter) == NULL)) {
return;
}
TRACE_INLINING(ISL_Print("Inlining calls in %s\n", top.ToCString()));
if (trace_inlining() &&
(FLAG_print_flow_graph || FLAG_print_flow_graph_optimized)) {
ISL_Print("Before Inlining of %s\n", flow_graph_->
function().ToFullyQualifiedCString());
FlowGraphPrinter printer(*flow_graph_);
printer.PrintBlocks();
}
CallSiteInliner inliner(this);
inliner.InlineCalls();
if (FLAG_print_inlining_tree) {
inliner.PrintInlinedInfo(top);
}
if (inliner.inlined()) {
flow_graph_->DiscoverBlocks();
if (trace_inlining()) {
ISL_Print("Inlining growth factor: %f\n", inliner.GrowthFactor());
if (FLAG_print_flow_graph || FLAG_print_flow_graph_optimized) {
ISL_Print("After Inlining of %s\n", flow_graph_->
function().ToFullyQualifiedCString());
FlowGraphPrinter printer(*flow_graph_);
printer.PrintBlocks();
}
}
}
}
intptr_t FlowGraphInliner::NextInlineId(const Function& function,
intptr_t parent_id) {
const intptr_t id = inline_id_to_function_->length();
inline_id_to_function_->Add(&function);
caller_inline_id_->Add(parent_id);
return id;
}
} // namespace dart