v8/test/cctest/compiler/test-osr.cc
bmeurer afc2fb26a1 [turbofan] Remove another ineffective optimization from the ControlReducer.
The condition of a Branch or Select can never be a NumberConstant,
because the resulting graph would be invalid, so we don't need to
optimize this case. It can only ever be a tagged boolean or an untagged
bit.

Drive-by-fix: Test the interesting cases in the unit tests instead.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/1195443004

Cr-Commit-Position: refs/heads/master@{#29089}
2015-06-17 12:50:45 +00:00

596 lines
19 KiB
C++

// 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/codegen.h"
#include "src/compiler/all-nodes.h"
#include "src/compiler/common-operator.h"
#include "src/compiler/diamond.h"
#include "src/compiler/graph.h"
#include "src/compiler/js-graph.h"
#include "src/compiler/js-operator.h"
#include "src/compiler/operator.h"
#include "src/compiler/osr.h"
#include "test/cctest/cctest.h"
using namespace v8::internal;
using namespace v8::internal::compiler;
// TODO(titzer): move this method to a common testing place.
static int CheckInputs(Node* node, Node* i0 = NULL, Node* i1 = NULL,
Node* i2 = NULL, Node* i3 = NULL) {
int count = 4;
if (i3 == NULL) count = 3;
if (i2 == NULL) count = 2;
if (i1 == NULL) count = 1;
if (i0 == NULL) count = 0;
CHECK_EQ(count, node->InputCount());
if (i0 != NULL) CHECK_EQ(i0, node->InputAt(0));
if (i1 != NULL) CHECK_EQ(i1, node->InputAt(1));
if (i2 != NULL) CHECK_EQ(i2, node->InputAt(2));
if (i3 != NULL) CHECK_EQ(i3, node->InputAt(3));
return count;
}
static Operator kIntLt(IrOpcode::kInt32LessThan, Operator::kPure,
"Int32LessThan", 2, 0, 0, 1, 0, 0);
static Operator kIntAdd(IrOpcode::kInt32Add, Operator::kPure, "Int32Add", 2, 0,
0, 1, 0, 0);
static const int kMaxOsrValues = 10;
class OsrDeconstructorTester : public HandleAndZoneScope {
public:
explicit OsrDeconstructorTester(int num_values)
: isolate(main_isolate()),
common(main_zone()),
graph(main_zone()),
jsgraph(main_isolate(), &graph, &common, NULL, NULL),
start(graph.NewNode(common.Start(1))),
p0(graph.NewNode(common.Parameter(0), start)),
end(graph.NewNode(common.End(1), start)),
osr_normal_entry(graph.NewNode(common.OsrNormalEntry(), start, start)),
osr_loop_entry(graph.NewNode(common.OsrLoopEntry(), start, start)),
self(graph.NewNode(common.Int32Constant(0xaabbccdd))) {
CHECK(num_values <= kMaxOsrValues);
graph.SetStart(start);
for (int i = 0; i < num_values; i++) {
osr_values[i] = graph.NewNode(common.OsrValue(i), osr_loop_entry);
}
}
Isolate* isolate;
CommonOperatorBuilder common;
Graph graph;
JSGraph jsgraph;
Node* start;
Node* p0;
Node* end;
Node* osr_normal_entry;
Node* osr_loop_entry;
Node* self;
Node* osr_values[kMaxOsrValues];
Node* NewOsrPhi(Node* loop, Node* incoming, int osr_value, Node* back1 = NULL,
Node* back2 = NULL, Node* back3 = NULL) {
int count = 5;
if (back3 == NULL) count = 4;
if (back2 == NULL) count = 3;
if (back1 == NULL) count = 2;
CHECK_EQ(loop->InputCount(), count);
CHECK_EQ(osr_loop_entry, loop->InputAt(1));
Node* inputs[6];
inputs[0] = incoming;
inputs[1] = osr_values[osr_value];
if (count > 2) inputs[2] = back1;
if (count > 3) inputs[3] = back2;
if (count > 4) inputs[4] = back3;
inputs[count] = loop;
return graph.NewNode(common.Phi(kMachAnyTagged, count), count + 1, inputs);
}
Node* NewLoop(bool is_osr, int num_backedges, Node* entry = NULL) {
CHECK_LT(num_backedges, 4);
CHECK_GE(num_backedges, 0);
int count = 1 + num_backedges;
if (entry == NULL) entry = osr_normal_entry;
Node* inputs[5] = {entry, self, self, self, self};
if (is_osr) {
count = 2 + num_backedges;
inputs[1] = osr_loop_entry;
}
Node* loop = graph.NewNode(common.Loop(count), count, inputs);
for (int i = 0; i < loop->InputCount(); i++) {
if (loop->InputAt(i) == self) loop->ReplaceInput(i, loop);
}
return loop;
}
Node* NewOsrLoop(int num_backedges, Node* entry = NULL) {
return NewLoop(true, num_backedges, entry);
}
void DeconstructOsr() {
OsrHelper helper(0, 0);
helper.Deconstruct(&jsgraph, &common, main_zone());
AllNodes nodes(main_zone(), &graph);
// Should be edited out.
CHECK(!nodes.IsLive(osr_normal_entry));
CHECK(!nodes.IsLive(osr_loop_entry));
// No dangling nodes should be left over.
for (Node* const node : nodes.live) {
for (Node* const use : node->uses()) {
CHECK(std::find(nodes.live.begin(), nodes.live.end(), use) !=
nodes.live.end());
}
}
}
};
TEST(Deconstruct_osr0) {
OsrDeconstructorTester T(0);
Node* loop = T.NewOsrLoop(1);
T.graph.SetEnd(loop);
T.DeconstructOsr();
CheckInputs(loop, T.start, loop);
}
TEST(Deconstruct_osr1) {
OsrDeconstructorTester T(1);
Node* loop = T.NewOsrLoop(1);
Node* osr_phi =
T.NewOsrPhi(loop, T.jsgraph.OneConstant(), 0, T.jsgraph.ZeroConstant());
Node* ret = T.graph.NewNode(T.common.Return(), osr_phi, T.start, loop);
T.graph.SetEnd(ret);
T.DeconstructOsr();
CheckInputs(loop, T.start, loop);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.ZeroConstant(), loop);
CheckInputs(ret, osr_phi, T.start, loop);
}
TEST(Deconstruct_osr1_type) {
OsrDeconstructorTester T(1);
Node* loop = T.NewOsrLoop(1);
Node* osr_phi =
T.NewOsrPhi(loop, T.jsgraph.OneConstant(), 0, T.jsgraph.ZeroConstant());
Type* type = Type::Signed32();
NodeProperties::SetBounds(osr_phi, Bounds(type, type));
Node* ret = T.graph.NewNode(T.common.Return(), osr_phi, T.start, loop);
T.graph.SetEnd(ret);
OsrHelper helper(0, 0);
helper.Deconstruct(&T.jsgraph, &T.common, T.main_zone());
CHECK_EQ(type, NodeProperties::GetBounds(T.osr_values[0]).lower);
CHECK_EQ(type, NodeProperties::GetBounds(T.osr_values[0]).upper);
CheckInputs(loop, T.start, loop);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.ZeroConstant(), loop);
CheckInputs(ret, osr_phi, T.start, loop);
}
TEST(Deconstruct_osr_remove_prologue) {
OsrDeconstructorTester T(1);
Diamond d(&T.graph, &T.common, T.p0);
d.Chain(T.osr_normal_entry);
Node* loop = T.NewOsrLoop(1, d.merge);
Node* osr_phi =
T.NewOsrPhi(loop, T.jsgraph.OneConstant(), 0, T.jsgraph.ZeroConstant());
Node* ret = T.graph.NewNode(T.common.Return(), osr_phi, T.start, loop);
T.graph.SetEnd(ret);
T.DeconstructOsr();
CheckInputs(loop, T.start, loop);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.ZeroConstant(), loop);
CheckInputs(ret, osr_phi, T.start, loop);
// The control before the loop should have been removed.
AllNodes nodes(T.main_zone(), &T.graph);
CHECK(!nodes.IsLive(d.branch));
CHECK(!nodes.IsLive(d.if_true));
CHECK(!nodes.IsLive(d.if_false));
CHECK(!nodes.IsLive(d.merge));
}
TEST(Deconstruct_osr_with_body1) {
OsrDeconstructorTester T(1);
Node* loop = T.NewOsrLoop(1);
Node* branch = T.graph.NewNode(T.common.Branch(), T.p0, loop);
Node* if_true = T.graph.NewNode(T.common.IfTrue(), branch);
Node* if_false = T.graph.NewNode(T.common.IfFalse(), branch);
loop->ReplaceInput(2, if_true);
Node* osr_phi =
T.NewOsrPhi(loop, T.jsgraph.OneConstant(), 0, T.jsgraph.ZeroConstant());
Node* ret = T.graph.NewNode(T.common.Return(), osr_phi, T.start, if_false);
T.graph.SetEnd(ret);
T.DeconstructOsr();
CheckInputs(loop, T.start, if_true);
CheckInputs(branch, T.p0, loop);
CheckInputs(if_true, branch);
CheckInputs(if_false, branch);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.ZeroConstant(), loop);
CheckInputs(ret, osr_phi, T.start, if_false);
}
TEST(Deconstruct_osr_with_body2) {
OsrDeconstructorTester T(1);
Node* loop = T.NewOsrLoop(1);
// Two chained branches in the the body of the loop.
Node* branch1 = T.graph.NewNode(T.common.Branch(), T.p0, loop);
Node* if_true1 = T.graph.NewNode(T.common.IfTrue(), branch1);
Node* if_false1 = T.graph.NewNode(T.common.IfFalse(), branch1);
Node* branch2 = T.graph.NewNode(T.common.Branch(), T.p0, if_true1);
Node* if_true2 = T.graph.NewNode(T.common.IfTrue(), branch2);
Node* if_false2 = T.graph.NewNode(T.common.IfFalse(), branch2);
loop->ReplaceInput(2, if_true2);
Node* osr_phi =
T.NewOsrPhi(loop, T.jsgraph.OneConstant(), 0, T.jsgraph.ZeroConstant());
Node* merge = T.graph.NewNode(T.common.Merge(2), if_false1, if_false2);
Node* ret = T.graph.NewNode(T.common.Return(), osr_phi, T.start, merge);
T.graph.SetEnd(ret);
T.DeconstructOsr();
CheckInputs(loop, T.start, if_true2);
CheckInputs(branch1, T.p0, loop);
CheckInputs(branch2, T.p0, if_true1);
CheckInputs(if_true1, branch1);
CheckInputs(if_false1, branch1);
CheckInputs(if_true2, branch2);
CheckInputs(if_false2, branch2);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.ZeroConstant(), loop);
CheckInputs(ret, osr_phi, T.start, merge);
CheckInputs(merge, if_false1, if_false2);
}
TEST(Deconstruct_osr_with_body3) {
OsrDeconstructorTester T(1);
Node* loop = T.NewOsrLoop(2);
// Two branches that create two different backedges.
Node* branch1 = T.graph.NewNode(T.common.Branch(), T.p0, loop);
Node* if_true1 = T.graph.NewNode(T.common.IfTrue(), branch1);
Node* if_false1 = T.graph.NewNode(T.common.IfFalse(), branch1);
Node* branch2 = T.graph.NewNode(T.common.Branch(), T.p0, if_true1);
Node* if_true2 = T.graph.NewNode(T.common.IfTrue(), branch2);
Node* if_false2 = T.graph.NewNode(T.common.IfFalse(), branch2);
loop->ReplaceInput(2, if_false1);
loop->ReplaceInput(3, if_true2);
Node* osr_phi =
T.NewOsrPhi(loop, T.jsgraph.OneConstant(), 0, T.jsgraph.ZeroConstant(),
T.jsgraph.ZeroConstant());
Node* ret = T.graph.NewNode(T.common.Return(), osr_phi, T.start, if_false2);
T.graph.SetEnd(ret);
T.DeconstructOsr();
CheckInputs(loop, T.start, if_false1, if_true2);
CheckInputs(branch1, T.p0, loop);
CheckInputs(branch2, T.p0, if_true1);
CheckInputs(if_true1, branch1);
CheckInputs(if_false1, branch1);
CheckInputs(if_true2, branch2);
CheckInputs(if_false2, branch2);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.ZeroConstant(),
T.jsgraph.ZeroConstant(), loop);
CheckInputs(ret, osr_phi, T.start, if_false2);
}
struct While {
OsrDeconstructorTester& t;
Node* branch;
Node* if_true;
Node* exit;
Node* loop;
While(OsrDeconstructorTester& R, Node* cond, bool is_osr, int backedges = 1)
: t(R) {
loop = t.NewLoop(is_osr, backedges);
branch = t.graph.NewNode(t.common.Branch(), cond, loop);
if_true = t.graph.NewNode(t.common.IfTrue(), branch);
exit = t.graph.NewNode(t.common.IfFalse(), branch);
loop->ReplaceInput(loop->InputCount() - 1, if_true);
}
void Nest(While& that) {
that.loop->ReplaceInput(that.loop->InputCount() - 1, exit);
this->loop->ReplaceInput(0, that.if_true);
}
Node* Phi(Node* i1, Node* i2, Node* i3) {
if (loop->InputCount() == 2) {
return t.graph.NewNode(t.common.Phi(kMachAnyTagged, 2), i1, i2, loop);
} else {
return t.graph.NewNode(t.common.Phi(kMachAnyTagged, 3), i1, i2, i3, loop);
}
}
};
static Node* FindSuccessor(Node* node, IrOpcode::Value opcode) {
for (Node* use : node->uses()) {
if (use->opcode() == opcode) return use;
}
UNREACHABLE(); // should have been found.
return nullptr;
}
TEST(Deconstruct_osr_nested1) {
OsrDeconstructorTester T(1);
While outer(T, T.p0, false);
While inner(T, T.p0, true);
inner.Nest(outer);
Node* outer_phi = outer.Phi(T.p0, T.p0, nullptr);
outer.branch->ReplaceInput(0, outer_phi);
Node* osr_phi = inner.Phi(T.jsgraph.TrueConstant(), T.osr_values[0],
T.jsgraph.FalseConstant());
inner.branch->ReplaceInput(0, osr_phi);
outer_phi->ReplaceInput(1, osr_phi);
Node* ret =
T.graph.NewNode(T.common.Return(), outer_phi, T.start, outer.exit);
Node* end = T.graph.NewNode(T.common.End(1), ret);
T.graph.SetEnd(end);
T.DeconstructOsr();
// Check structure of deconstructed graph.
// Check inner OSR loop is directly connected to start.
CheckInputs(inner.loop, T.start, inner.if_true);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.FalseConstant(), inner.loop);
// Check control transfer to copy of outer loop.
Node* new_outer_loop = FindSuccessor(inner.exit, IrOpcode::kLoop);
Node* new_outer_phi = FindSuccessor(new_outer_loop, IrOpcode::kPhi);
CHECK_NE(new_outer_loop, outer.loop);
CHECK_NE(new_outer_phi, outer_phi);
CheckInputs(new_outer_loop, inner.exit, new_outer_loop->InputAt(1));
// Check structure of outer loop.
Node* new_outer_branch = FindSuccessor(new_outer_loop, IrOpcode::kBranch);
CHECK_NE(new_outer_branch, outer.branch);
CheckInputs(new_outer_branch, new_outer_phi, new_outer_loop);
Node* new_outer_exit = FindSuccessor(new_outer_branch, IrOpcode::kIfFalse);
Node* new_outer_if_true = FindSuccessor(new_outer_branch, IrOpcode::kIfTrue);
// Check structure of return.
end = T.graph.end();
Node* new_ret = end->InputAt(0);
CHECK_EQ(IrOpcode::kReturn, new_ret->opcode());
CheckInputs(new_ret, new_outer_phi, T.start, new_outer_exit);
// Check structure of inner loop.
Node* new_inner_loop = FindSuccessor(new_outer_if_true, IrOpcode::kLoop);
Node* new_inner_phi = FindSuccessor(new_inner_loop, IrOpcode::kPhi);
CheckInputs(new_inner_phi, T.jsgraph.TrueConstant(),
T.jsgraph.FalseConstant(), new_inner_loop);
CheckInputs(new_outer_phi, osr_phi, new_inner_phi, new_outer_loop);
}
TEST(Deconstruct_osr_nested2) {
OsrDeconstructorTester T(1);
// Test multiple backedge outer loop.
While outer(T, T.p0, false, 2);
While inner(T, T.p0, true);
inner.Nest(outer);
Node* outer_phi = outer.Phi(T.p0, T.p0, T.p0);
outer.branch->ReplaceInput(0, outer_phi);
Node* osr_phi = inner.Phi(T.jsgraph.TrueConstant(), T.osr_values[0],
T.jsgraph.FalseConstant());
inner.branch->ReplaceInput(0, osr_phi);
outer_phi->ReplaceInput(1, osr_phi);
outer_phi->ReplaceInput(2, T.jsgraph.FalseConstant());
Node* x_branch = T.graph.NewNode(T.common.Branch(), osr_phi, inner.exit);
Node* x_true = T.graph.NewNode(T.common.IfTrue(), x_branch);
Node* x_false = T.graph.NewNode(T.common.IfFalse(), x_branch);
outer.loop->ReplaceInput(1, x_true);
outer.loop->ReplaceInput(2, x_false);
Node* ret =
T.graph.NewNode(T.common.Return(), outer_phi, T.start, outer.exit);
Node* end = T.graph.NewNode(T.common.End(1), ret);
T.graph.SetEnd(end);
T.DeconstructOsr();
// Check structure of deconstructed graph.
// Check inner OSR loop is directly connected to start.
CheckInputs(inner.loop, T.start, inner.if_true);
CheckInputs(osr_phi, T.osr_values[0], T.jsgraph.FalseConstant(), inner.loop);
// Check control transfer to copy of outer loop.
Node* new_merge = FindSuccessor(x_true, IrOpcode::kMerge);
CHECK_EQ(new_merge, FindSuccessor(x_false, IrOpcode::kMerge));
CheckInputs(new_merge, x_true, x_false);
Node* new_outer_loop = FindSuccessor(new_merge, IrOpcode::kLoop);
Node* new_outer_phi = FindSuccessor(new_outer_loop, IrOpcode::kPhi);
CHECK_NE(new_outer_loop, outer.loop);
CHECK_NE(new_outer_phi, outer_phi);
Node* new_entry_phi = FindSuccessor(new_merge, IrOpcode::kPhi);
CheckInputs(new_entry_phi, osr_phi, T.jsgraph.FalseConstant(), new_merge);
CHECK_EQ(new_merge, new_outer_loop->InputAt(0));
// Check structure of outer loop.
Node* new_outer_branch = FindSuccessor(new_outer_loop, IrOpcode::kBranch);
CHECK_NE(new_outer_branch, outer.branch);
CheckInputs(new_outer_branch, new_outer_phi, new_outer_loop);
Node* new_outer_exit = FindSuccessor(new_outer_branch, IrOpcode::kIfFalse);
Node* new_outer_if_true = FindSuccessor(new_outer_branch, IrOpcode::kIfTrue);
// Check structure of return.
end = T.graph.end();
Node* new_ret = end->InputAt(0);
CHECK_EQ(IrOpcode::kReturn, new_ret->opcode());
CheckInputs(new_ret, new_outer_phi, T.start, new_outer_exit);
// Check structure of inner loop.
Node* new_inner_loop = FindSuccessor(new_outer_if_true, IrOpcode::kLoop);
Node* new_inner_phi = FindSuccessor(new_inner_loop, IrOpcode::kPhi);
CheckInputs(new_inner_phi, T.jsgraph.TrueConstant(),
T.jsgraph.FalseConstant(), new_inner_loop);
CheckInputs(new_outer_phi, new_entry_phi, new_inner_phi,
T.jsgraph.FalseConstant(), new_outer_loop);
}
Node* MakeCounter(JSGraph* jsgraph, Node* start, Node* loop) {
int count = loop->InputCount();
NodeVector tmp_inputs(jsgraph->graph()->zone());
for (int i = 0; i < count; i++) {
tmp_inputs.push_back(start);
}
tmp_inputs.push_back(loop);
Node* phi = jsgraph->graph()->NewNode(
jsgraph->common()->Phi(kMachInt32, count), count + 1, &tmp_inputs[0]);
Node* inc = jsgraph->graph()->NewNode(&kIntAdd, phi, jsgraph->OneConstant());
for (int i = 1; i < count; i++) {
phi->ReplaceInput(i, inc);
}
return phi;
}
TEST(Deconstruct_osr_nested3) {
OsrDeconstructorTester T(1);
// outermost loop.
While loop0(T, T.p0, false, 1);
Node* loop0_cntr = MakeCounter(&T.jsgraph, T.p0, loop0.loop);
loop0.branch->ReplaceInput(0, loop0_cntr);
// middle loop.
Node* loop1 = T.graph.NewNode(T.common.Loop(2), loop0.if_true, T.self);
loop1->ReplaceInput(0, loop0.if_true);
Node* loop1_phi = T.graph.NewNode(T.common.Phi(kMachAnyTagged, 2), loop0_cntr,
loop0_cntr, loop1);
// innermost (OSR) loop.
While loop2(T, T.p0, true, 1);
loop2.loop->ReplaceInput(0, loop1);
Node* loop2_cntr = MakeCounter(&T.jsgraph, loop1_phi, loop2.loop);
loop2_cntr->ReplaceInput(1, T.osr_values[0]);
Node* osr_phi = loop2_cntr;
Node* loop2_inc = loop2_cntr->InputAt(2);
loop2.branch->ReplaceInput(0, loop2_cntr);
loop1_phi->ReplaceInput(1, loop2_cntr);
loop0_cntr->ReplaceInput(1, loop2_cntr);
// Branch to either the outer or middle loop.
Node* branch = T.graph.NewNode(T.common.Branch(), loop2_cntr, loop2.exit);
Node* if_true = T.graph.NewNode(T.common.IfTrue(), branch);
Node* if_false = T.graph.NewNode(T.common.IfFalse(), branch);
loop0.loop->ReplaceInput(1, if_true);
loop1->ReplaceInput(1, if_false);
Node* ret =
T.graph.NewNode(T.common.Return(), loop0_cntr, T.start, loop0.exit);
Node* end = T.graph.NewNode(T.common.End(1), ret);
T.graph.SetEnd(end);
T.DeconstructOsr();
// Check structure of deconstructed graph.
// Check loop2 (OSR loop) is directly connected to start.
CheckInputs(loop2.loop, T.start, loop2.if_true);
CheckInputs(osr_phi, T.osr_values[0], loop2_inc, loop2.loop);
CheckInputs(loop2.branch, osr_phi, loop2.loop);
CheckInputs(loop2.if_true, loop2.branch);
CheckInputs(loop2.exit, loop2.branch);
CheckInputs(branch, osr_phi, loop2.exit);
CheckInputs(if_true, branch);
CheckInputs(if_false, branch);
// Check structure of new_loop1.
Node* new_loop1_loop = FindSuccessor(if_false, IrOpcode::kLoop);
// TODO(titzer): check the internal copy of loop2.
USE(new_loop1_loop);
// Check structure of new_loop0.
Node* new_loop0_loop_entry = FindSuccessor(if_true, IrOpcode::kMerge);
Node* new_loop0_loop = FindSuccessor(new_loop0_loop_entry, IrOpcode::kLoop);
// TODO(titzer): check the internal copies of loop1 and loop2.
Node* new_loop0_branch = FindSuccessor(new_loop0_loop, IrOpcode::kBranch);
Node* new_loop0_if_true = FindSuccessor(new_loop0_branch, IrOpcode::kIfTrue);
Node* new_loop0_exit = FindSuccessor(new_loop0_branch, IrOpcode::kIfFalse);
USE(new_loop0_if_true);
Node* new_ret = T.graph.end()->InputAt(0);
CHECK_EQ(IrOpcode::kReturn, new_ret->opcode());
Node* new_loop0_phi = new_ret->InputAt(0);
CHECK_EQ(IrOpcode::kPhi, new_loop0_phi->opcode());
CHECK_EQ(new_loop0_loop, NodeProperties::GetControlInput(new_loop0_phi));
CHECK_EQ(new_loop0_phi, FindSuccessor(new_loop0_loop, IrOpcode::kPhi));
// Check that the return returns the phi from the OSR loop and control
// depends on the copy of the outer loop0.
CheckInputs(new_ret, new_loop0_phi, T.graph.start(), new_loop0_exit);
}