[stubs] Split ToNumberStub into reusable subparts.

src/mips64/macro-assembler-mips64.h

Index: src/mips64/macro-assembler-mips64.h
diff --git a/src/mips64/macro-assembler-mips64.h b/src/mips64/macro-assembler-mips64.h
index 37574efd3efb5391cfe0dc3f022c97ea7180886a..884a0019d7f3c7abcd6045273f57afc45acf32cd 100644
--- a/src/mips64/macro-assembler-mips64.h
+++ b/src/mips64/macro-assembler-mips64.h
@@ -1671,6 +1671,9 @@ const Operand& rt = Operand(zero_reg), BranchDelaySlot bd = PROTECT
   // Jump if either of the registers contain a smi.
   void JumpIfEitherSmi(Register reg1, Register reg2, Label* on_either_smi);
 
+  // Abort execution if argument is a number, enabled via --debug-code.
+  void AssertNotNumber(Register object);
+
   // Abort execution if argument is a smi, enabled via --debug-code.
   void AssertNotSmi(Register object);
   void AssertSmi(Register object);