[runtime] Introduce dedicated JSBoundFunction to represent bound functions.

src/mips/macro-assembler-mips.cc

Index: src/mips/macro-assembler-mips.cc
diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc
index 611ed32a9fb11c32c4db724d57f1095e64622fdc..f24e5e37fdf677fd1233d96c4a1bab3c1a13b9b5 100644
--- a/src/mips/macro-assembler-mips.cc
+++ b/src/mips/macro-assembler-mips.cc
@@ -5123,6 +5123,17 @@ void MacroAssembler::AssertFunction(Register object) {
 }
 
 
+void MacroAssembler::AssertBoundFunction(Register object) {
+  if (emit_debug_code()) {
+    STATIC_ASSERT(kSmiTag == 0);
+    SmiTst(object, t8);
+    Check(ne, kOperandIsASmiAndNotABoundFunction, t8, Operand(zero_reg));
+    GetObjectType(object, t8, t8);
+    Check(eq, kOperandIsNotABoundFunction, t8, Operand(JS_BOUND_FUNCTION_TYPE));
+  }
+}
+
+
 void MacroAssembler::AssertUndefinedOrAllocationSite(Register object,
                                                      Register scratch) {
   if (emit_debug_code()) {