Simplify stackframe of construct stub on ARM and MIPS.

src/mips/builtins-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 906 matching lines @@
     // Allocate the new receiver object using the runtime call.
     // a1: constructor function
     __ push(a1);  // Argument for Runtime_NewObject.
     __ CallRuntime(Runtime::kNewObject, 1);
     __ mov(t4, v0);
 
     // Receiver for constructor call allocated.
     // t4: JSObject
     __ bind(&allocated);
     __ push(t4);
-
-    // Push the function and the allocated receiver from the stack.
-    // sp[0]: receiver (newly allocated object)
-    // sp[1]: constructor function
-    // sp[2]: number of arguments (smi-tagged)
-    __ lw(a1, MemOperand(sp, kPointerSize));
-    __ MultiPushReversed(a1.bit() | t4.bit());
+    __ push(t4);
 
     // Reload the number of arguments from the stack.
-    // a1: constructor function
     // sp[0]: receiver
-    // sp[1]: constructor function
-    // sp[2]: receiver
-    // sp[3]: constructor function
-    // sp[4]: number of arguments (smi-tagged)
-    __ lw(a3, MemOperand(sp, 4 * kPointerSize));
+    // sp[1]: receiver
+    // sp[2]: constructor function
+    // sp[3]: number of arguments (smi-tagged)
+    __ lw(a1, MemOperand(sp, 2 * kPointerSize));
+    __ lw(a3, MemOperand(sp, 3 * kPointerSize));
 
     // Set up pointer to last argument.
     __ Addu(a2, fp, Operand(StandardFrameConstants::kCallerSPOffset));
 
     // Set up number of arguments for function call below.
     __ srl(a0, a3, kSmiTagSize);
 
     // Copy arguments and receiver to the expression stack.
     // a0: number of arguments
     // a1: constructor function
     // a2: address of last argument (caller sp)
     // a3: number of arguments (smi-tagged)
     // sp[0]: receiver
-    // sp[1]: constructor function
-    // sp[2]: receiver
-    // sp[3]: constructor function
-    // sp[4]: number of arguments (smi-tagged)
+    // sp[1]: receiver
+    // sp[2]: constructor function
+    // sp[3]: number of arguments (smi-tagged)
     Label loop, entry;
     __ jmp(&entry);
     __ bind(&loop);
     __ sll(t0, a3, kPointerSizeLog2 - kSmiTagSize);
     __ Addu(t0, a2, Operand(t0));
     __ lw(t1, MemOperand(t0));
     __ push(t1);
     __ bind(&entry);
     __ Addu(a3, a3, Operand(-2));
     __ Branch(&loop, greater_equal, a3, Operand(zero_reg));
 
     // Call the function.
     // a0: number of arguments
     // a1: constructor function
     if (is_api_function) {
       __ lw(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
       Handle<Code> code =
           masm->isolate()->builtins()->HandleApiCallConstruct();
       ParameterCount expected(0);
       __ InvokeCode(code, expected, expected,
                     RelocInfo::CODE_TARGET, CALL_FUNCTION, CALL_AS_METHOD);
     } else {
       ParameterCount actual(a0);
       __ InvokeFunction(a1, actual, CALL_FUNCTION,
                         NullCallWrapper(), CALL_AS_METHOD);
     }
 
-    // Pop the function from the stack.
-    // v0: result
-    // sp[0]: constructor function
-    // sp[2]: receiver
-    // sp[3]: constructor function
-    // sp[4]: number of arguments (smi-tagged)
-    __ Pop();
-
     // Restore context from the frame.
     __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
 
     // If the result is an object (in the ECMA sense), we should get rid
     // of the receiver and use the result; see ECMA-262 section 13.2.2-7
     // on page 74.
     Label use_receiver, exit;
 
     // If the result is a smi, it is *not* an object in the ECMA sense.
     // v0: result
@@ skipping 768 matching lines @@
   __ bind(&dont_adapt_arguments);
   __ Jump(a3);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS