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

src/register-configuration.h

Index: src/register-configuration.h
diff --git a/src/register-configuration.h b/src/register-configuration.h
index cd09a88988d75b75c5f6383e01ee48877f64b1c4..946c82e56cd4e25709e368a33c7489e339c63d28 100644
--- a/src/register-configuration.h
+++ b/src/register-configuration.h
@@ -36,7 +36,6 @@ class V8_EXPORT_PRIVATE RegisterConfiguration {
   RegisterConfiguration(int num_general_registers, int num_double_registers,
                         int num_allocatable_general_registers,
                         int num_allocatable_double_registers,
-                        int num_allocatable_aliased_double_registers,
                         const int* allocatable_general_codes,
                         const int* allocatable_double_codes,
                         AliasingKind fp_aliasing_kind,
@@ -58,12 +57,6 @@ class V8_EXPORT_PRIVATE RegisterConfiguration {
   int num_allocatable_double_registers() const {
     return num_allocatable_double_registers_;
   }
-  // TODO(bbudge): This is a temporary work-around required because our
-  // register allocator does not yet support the aliasing of single/double
-  // registers on ARM.
-  int num_allocatable_aliased_double_registers() const {
-    return num_allocatable_aliased_double_registers_;
-  }
   int num_allocatable_simd128_registers() const {
     return num_allocatable_simd128_registers_;
   }
@@ -143,7 +136,6 @@ class V8_EXPORT_PRIVATE RegisterConfiguration {
   int num_allocatable_general_registers_;
   int num_allocatable_float_registers_;
   int num_allocatable_double_registers_;
-  int num_allocatable_aliased_double_registers_;
   int num_allocatable_simd128_registers_;
   int32_t allocatable_general_codes_mask_;
   int32_t allocatable_float_codes_mask_;