[turbofan] delay inserting spill slots for parent ranges.

test/unittests/compiler/register-allocator-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 "src/compiler/pipeline.h"
 #include "test/unittests/compiler/instruction-sequence-unittest.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
@@ skipping 134 matching lines @@
 }
 
 
 TEST_F(RegisterAllocatorTest, DoubleDiamondManyRedundantPhis) {
   const int kPhis = kDefaultNRegs * 2;
 
   // First diamond.
   StartBlock();
   VReg vals[kPhis];
   for (int i = 0; i < kPhis; ++i) {
-    vals[i] = Parameter(Slot(i));
+    vals[i] = Parameter(Slot(-1 - i));
   }
   EndBlock(Branch(Reg(DefineConstant()), 1, 2));
 
   StartBlock();
   EndBlock(Jump(2));
 
   StartBlock();
   EndBlock(Jump(1));
 
   // Second diamond.
@@ skipping 104 matching lines @@
   }
   EmitCall(Slot(-1), arraysize(call_ops), call_ops);
   EndBlock(Last());
 
   Allocate();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8