[turbofan] reduce allocations outside of pipeline

test/unittests/compiler/instruction-selector-unittest.cc

 // Copyright 2014 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 "test/unittests/compiler/instruction-selector-unittest.h"
 
 #include "src/compiler/graph-inl.h"
 #include "src/flags.h"
 #include "test/unittests/compiler/compiler-test-utils.h"
 
@@ skipping 18 matching lines @@
     InstructionSelector::Features features,
     InstructionSelectorTest::StreamBuilderMode mode) {
   Schedule* schedule = Export();
   if (FLAG_trace_turbo) {
     OFStream out(stdout);
     out << "=== Schedule before instruction selection ===" << std::endl
         << *schedule;
   }
   EXPECT_NE(0, graph()->NodeCount());
   int initial_node_count = graph()->NodeCount();
-  CompilationInfo info(test_->isolate(), test_->zone());
-  Linkage linkage(&info, call_descriptor());
+  Linkage linkage(test_->zone(), call_descriptor());
   InstructionSequence sequence(test_->zone(), graph(), schedule);
   SourcePositionTable source_position_table(graph());
   InstructionSelector selector(test_->zone(), &linkage, &sequence, schedule,
                                &source_position_table, features);
   selector.SelectInstructions();
   if (FLAG_trace_turbo) {
     OFStream out(stdout);
     out << "=== Code sequence after instruction selection ===" << std::endl
         << sequence;
   }
@@ skipping 518 matching lines @@
   EXPECT_EQ(s.ToVreg(context2), s.ToVreg(call_instr->InputAt(12)));
   // Continuation.
 
   EXPECT_EQ(kArchRet, s[index++]->arch_opcode());
   EXPECT_EQ(index, s.size());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8