MIPS: [turbofan] Add backend support for float32.

src/mips64/assembler-mips64-inl.h

Index: src/mips64/assembler-mips64-inl.h
diff --git a/src/mips64/assembler-mips64-inl.h b/src/mips64/assembler-mips64-inl.h
index de294ee6653408126d85bd46a4016623626fa497..76dd801af591b259d3de1b21601401806dcd687e 100644
--- a/src/mips64/assembler-mips64-inl.h
+++ b/src/mips64/assembler-mips64-inl.h
@@ -99,6 +99,11 @@ int DoubleRegister::NumAllocatableRegisters() {
 }
 
 
+int DoubleRegister::NumAllocatableAliasedRegisters() {
+  return NumAllocatableRegisters();
+}
+
+
 int FPURegister::ToAllocationIndex(FPURegister reg) {
   DCHECK(reg.code() % 2 == 0);
   DCHECK(reg.code() / 2 < kMaxNumAllocatableRegisters);