[turbofan] Remove last_use_ field from Node.

test/unittests/compiler/node-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/node.h"
 #include "src/compiler/operator.h"
 #include "test/unittests/test-utils.h"
 #include "testing/gmock-support.h"
 
 using testing::ElementsAre;
@@ skipping 24 matching lines @@
   EXPECT_EQ(1, node->id());
   EXPECT_EQ(0, node->UseCount());
   EXPECT_TRUE(node->uses().empty());
   EXPECT_EQ(0, node->InputCount());
   EXPECT_TRUE(node->inputs().empty());
   EXPECT_EQ(&kOp0, node->op());
   EXPECT_EQ(kOpcode0, node->opcode());
 }
 
 
+// TODO(titzer): stupid test is stupid.
+static Node* UseAt(Node* node, int index) {

[Benedikt Meurer, 2015/03/19 09:46:23]

There should be no need for this helper method.

[titzer, 2015/03/19 10:10:31]

Done.

+  for (Node* use : node->uses()) {
+    if (index-- <= 0) return use;
+  }
+  return nullptr;
+}
+
+
 TEST_F(NodeTest, NewWithInputs) {
   Node* n0 = Node::New(zone(), 0, &kOp0, 0, nullptr, false);
   EXPECT_EQ(0, n0->UseCount());
   EXPECT_EQ(0, n0->InputCount());
   Node* n1 = Node::New(zone(), 1, &kOp1, 1, &n0, false);
   EXPECT_EQ(1, n0->UseCount());
-  EXPECT_EQ(n1, n0->UseAt(0));
+  EXPECT_EQ(n1, UseAt(n0, 0));

[Michael Starzinger, 2015/03/19 09:40:09]

Can we use EXPECT_THAT(n1->uses(), ElementsAre(n0)) here?

[titzer, 2015/03/19 10:10:31]

Done.

   EXPECT_EQ(0, n1->UseCount());
   EXPECT_EQ(1, n1->InputCount());
   EXPECT_EQ(n0, n1->InputAt(0));
   Node* n0_n1[] = {n0, n1};
   Node* n2 = Node::New(zone(), 2, &kOp2, 2, n0_n1, false);
   EXPECT_EQ(2, n0->UseCount());
-  EXPECT_EQ(n1, n0->UseAt(0));
-  EXPECT_EQ(n2, n0->UseAt(1));
+  EXPECT_EQ(n1, UseAt(n0, 1));

[Michael Starzinger, 2015/03/19 09:40:08]

Can we use EXPECT_THAT(n0->uses(), ElementsAre(n0, n1)) here?

[titzer, 2015/03/19 10:10:31]

Done.

+  EXPECT_EQ(n2, UseAt(n1, 0));
   EXPECT_EQ(2, n2->InputCount());
   EXPECT_EQ(n0, n2->InputAt(0));
   EXPECT_EQ(n1, n2->InputAt(1));
 }
 
 
 TEST_F(NodeTest, InputIteratorEmpty) {
   Node* node = Node::New(zone(), 0, &kOp0, 0, nullptr, false);
   EXPECT_EQ(node->inputs().begin(), node->inputs().end());
 }
@@ skipping 91 matching lines @@
   EXPECT_THAT(node->inputs(), ElementsAre(n0, n1, n0));
   node->AppendInput(zone(), n0);
   EXPECT_THAT(node->inputs(), ElementsAre(n0, n1, n0, n0));
   node->AppendInput(zone(), n1);
   EXPECT_THAT(node->inputs(), ElementsAre(n0, n1, n0, n0, n1));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8