[turbofan] Fix tail call optimization.

test/unittests/compiler/tail-call-optimization-unittest.cc

+// 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/linkage.h"
+#include "src/compiler/tail-call-optimization.h"
+#include "test/unittests/compiler/graph-unittest.h"
+#include "test/unittests/compiler/node-test-utils.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+class TailCallOptimizationTest : public GraphTest {
+ public:
+  explicit TailCallOptimizationTest(int num_parameters = 1)
+      : GraphTest(num_parameters) {}
+  ~TailCallOptimizationTest() override {}
+
+ protected:
+  Reduction Reduce(Node* node) {
+    TailCallOptimization tco(common(), graph());
+    return tco.Reduce(node);
+  }
+};
+
+
+TEST_F(TailCallOptimizationTest, CallCodeObject0) {
+  MachineType kMachineSignature[] = {kMachAnyTagged, kMachAnyTagged};
+  LinkageLocation kLocationSignature[] = {LinkageLocation(0),
+                                          LinkageLocation(1)};
+  const CallDescriptor* kCallDescriptor = new (zone()) CallDescriptor(
+      CallDescriptor::kCallCodeObject, kMachAnyTagged, LinkageLocation(0),
+      new (zone()) MachineSignature(1, 1, kMachineSignature),
+      new (zone()) LocationSignature(1, 1, kLocationSignature), 0,
+      Operator::kNoProperties, 0, CallDescriptor::kNoFlags);
+  Node* p0 = Parameter(0);
+  Node* p1 = Parameter(1);
+  Node* call = graph()->NewNode(common()->Call(kCallDescriptor), p0, p1,
+                                graph()->start(), graph()->start());
+  Node* if_success = graph()->NewNode(common()->IfSuccess(), call);
+  Node* ret = graph()->NewNode(common()->Return(), call, call, if_success);
+  Reduction r = Reduce(ret);
+  ASSERT_FALSE(r.Changed());
+}
+
+
+TEST_F(TailCallOptimizationTest, CallCodeObject1) {
+  MachineType kMachineSignature[] = {kMachAnyTagged, kMachAnyTagged};
+  LinkageLocation kLocationSignature[] = {LinkageLocation(0),
+                                          LinkageLocation(1)};
+  const CallDescriptor* kCallDescriptor = new (zone()) CallDescriptor(
+      CallDescriptor::kCallCodeObject, kMachAnyTagged, LinkageLocation(0),
+      new (zone()) MachineSignature(1, 1, kMachineSignature),
+      new (zone()) LocationSignature(1, 1, kLocationSignature), 0,
+      Operator::kNoProperties, 0, CallDescriptor::kSupportsTailCalls);
+  Node* p0 = Parameter(0);
+  Node* p1 = Parameter(1);
+  Node* call = graph()->NewNode(common()->Call(kCallDescriptor), p0, p1,
+                                graph()->start(), graph()->start());
+  Node* if_success = graph()->NewNode(common()->IfSuccess(), call);
+  Node* if_exception = graph()->NewNode(common()->IfException(), call);
+  Node* ret = graph()->NewNode(common()->Return(), call, call, if_success);
+  Node* end = graph()->NewNode(common()->End(), if_exception);
+  graph()->SetEnd(end);
+  Reduction r = Reduce(ret);
+  ASSERT_FALSE(r.Changed());
+}
+
+
+TEST_F(TailCallOptimizationTest, CallCodeObject2) {
+  MachineType kMachineSignature[] = {kMachAnyTagged, kMachAnyTagged};
+  LinkageLocation kLocationSignature[] = {LinkageLocation(0),
+                                          LinkageLocation(1)};
+  const CallDescriptor* kCallDescriptor = new (zone()) CallDescriptor(
+      CallDescriptor::kCallCodeObject, kMachAnyTagged, LinkageLocation(0),
+      new (zone()) MachineSignature(1, 1, kMachineSignature),
+      new (zone()) LocationSignature(1, 1, kLocationSignature), 0,
+      Operator::kNoProperties, 0, CallDescriptor::kSupportsTailCalls);
+  Node* p0 = Parameter(0);
+  Node* p1 = Parameter(1);
+  Node* call = graph()->NewNode(common()->Call(kCallDescriptor), p0, p1,
+                                graph()->start(), graph()->start());
+  Node* if_success = graph()->NewNode(common()->IfSuccess(), call);
+  Node* ret = graph()->NewNode(common()->Return(), call, call, if_success);
+  Reduction r = Reduce(ret);
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(), IsTailCall(kCallDescriptor, p0, p1,
+                                          graph()->start(), graph()->start()));
+}
+
+
+TEST_F(TailCallOptimizationTest, CallJSFunction0) {
+  MachineType kMachineSignature[] = {kMachAnyTagged, kMachAnyTagged};
+  LinkageLocation kLocationSignature[] = {LinkageLocation(0),
+                                          LinkageLocation(1)};
+  const CallDescriptor* kCallDescriptor = new (zone()) CallDescriptor(
+      CallDescriptor::kCallJSFunction, kMachAnyTagged, LinkageLocation(0),
+      new (zone()) MachineSignature(1, 1, kMachineSignature),
+      new (zone()) LocationSignature(1, 1, kLocationSignature), 0,
+      Operator::kNoProperties, 0, CallDescriptor::kNoFlags);
+  Node* p0 = Parameter(0);
+  Node* p1 = Parameter(1);
+  Node* call = graph()->NewNode(common()->Call(kCallDescriptor), p0, p1,
+                                graph()->start(), graph()->start());
+  Node* if_success = graph()->NewNode(common()->IfSuccess(), call);
+  Node* ret = graph()->NewNode(common()->Return(), call, call, if_success);
+  Reduction r = Reduce(ret);
+  ASSERT_FALSE(r.Changed());
+}
+
+
+TEST_F(TailCallOptimizationTest, CallJSFunction1) {
+  MachineType kMachineSignature[] = {kMachAnyTagged, kMachAnyTagged};
+  LinkageLocation kLocationSignature[] = {LinkageLocation(0),
+                                          LinkageLocation(1)};
+  const CallDescriptor* kCallDescriptor = new (zone()) CallDescriptor(
+      CallDescriptor::kCallJSFunction, kMachAnyTagged, LinkageLocation(0),
+      new (zone()) MachineSignature(1, 1, kMachineSignature),
+      new (zone()) LocationSignature(1, 1, kLocationSignature), 0,
+      Operator::kNoProperties, 0, CallDescriptor::kSupportsTailCalls);
+  Node* p0 = Parameter(0);
+  Node* p1 = Parameter(1);
+  Node* call = graph()->NewNode(common()->Call(kCallDescriptor), p0, p1,
+                                graph()->start(), graph()->start());
+  Node* if_success = graph()->NewNode(common()->IfSuccess(), call);
+  Node* if_exception = graph()->NewNode(common()->IfException(), call);
+  Node* ret = graph()->NewNode(common()->Return(), call, call, if_success);
+  Node* end = graph()->NewNode(common()->End(), if_exception);
+  graph()->SetEnd(end);
+  Reduction r = Reduce(ret);
+  ASSERT_FALSE(r.Changed());
+}
+
+
+TEST_F(TailCallOptimizationTest, CallJSFunction2) {
+  MachineType kMachineSignature[] = {kMachAnyTagged, kMachAnyTagged};
+  LinkageLocation kLocationSignature[] = {LinkageLocation(0),
+                                          LinkageLocation(1)};
+  const CallDescriptor* kCallDescriptor = new (zone()) CallDescriptor(
+      CallDescriptor::kCallJSFunction, kMachAnyTagged, LinkageLocation(0),
+      new (zone()) MachineSignature(1, 1, kMachineSignature),
+      new (zone()) LocationSignature(1, 1, kLocationSignature), 0,
+      Operator::kNoProperties, 0, CallDescriptor::kSupportsTailCalls);
+  Node* p0 = Parameter(0);
+  Node* p1 = Parameter(1);
+  Node* call = graph()->NewNode(common()->Call(kCallDescriptor), p0, p1,
+                                graph()->start(), graph()->start());
+  Node* if_success = graph()->NewNode(common()->IfSuccess(), call);
+  Node* ret = graph()->NewNode(common()->Return(), call, call, if_success);
+  Reduction r = Reduce(ret);
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(), IsTailCall(kCallDescriptor, p0, p1,
+                                          graph()->start(), graph()->start()));
+}
+
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8