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

test/unittests/compiler/register-allocator-unittest.cc

Index: test/unittests/compiler/register-allocator-unittest.cc
diff --git a/test/unittests/compiler/register-allocator-unittest.cc b/test/unittests/compiler/register-allocator-unittest.cc
index 22b1b4448570a1ace42a0de35fbbae45ac0cef2f..ed3558dc609606daaf366e83e02cbb704147a6ec 100644
--- a/test/unittests/compiler/register-allocator-unittest.cc
+++ b/test/unittests/compiler/register-allocator-unittest.cc
@@ -101,13 +101,14 @@ TEST_F(RegisterAllocatorTest, CanAllocateThreeRegisters) {
   Allocate();
 }
 
-TEST_F(RegisterAllocatorTest, CanAllocateThreeFPRegisters) {
-  // return p0 + p1;
-  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);
+TEST_F(RegisterAllocatorTest, CanAllocateFPRegisters) {
+  StartBlock();
+  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();