[Turbofan] Add concept of FP register aliasing on ARM 32.

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 83 matching lines @@
   StartBlock();
   auto a_reg = Parameter();
   auto b_reg = Parameter();
   auto c_reg = EmitOI(Reg(1), Reg(a_reg, 1), Reg(b_reg, 0));
   Return(c_reg);
   EndBlock(Last());
 
   Allocate();
 }
 
-TEST_F(RegisterAllocatorTest, CanAllocateThreeFPRegisters) {
-  // return p0 + p1;
+TEST_F(RegisterAllocatorTest, CanAllocateFPRegisters) {
   StartBlock();
-  VReg a_reg = FPParameter();
-  VReg b_reg = FPParameter();
-  VReg c_reg = EmitOI(FPReg(1), Reg(a_reg, 1), Reg(b_reg, 0));
-  Return(c_reg);
+  TestOperand inputs[] = {
+      Reg(FPParameter(kFloat64)), Reg(FPParameter(kFloat64)),
+      Reg(FPParameter(kFloat32)), Reg(FPParameter(kFloat32)),
+      Reg(FPParameter(kSimd128)), Reg(FPParameter(kSimd128))};
+  VReg out1 = EmitOI(FPReg(1, kFloat64), arraysize(inputs), inputs);
+  Return(out1);
   EndBlock(Last());
 
   Allocate();
 }
 
 TEST_F(RegisterAllocatorTest, SimpleLoop) {
   // i = K;
   // while(true) { i++ }
   StartBlock();
   auto i_reg = DefineConstant();
@@ skipping 667 matching lines @@
 INSTANTIATE_TEST_CASE_P(
     RegisterAllocatorTest, SlotConstraintTest,
     ::testing::Combine(::testing::ValuesIn(kParameterTypes),
                        ::testing::Range(0, SlotConstraintTest::kMaxVariant)));
 
 #endif  // GTEST_HAS_COMBINE
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8