MIPS: new style of property/function callbacks

src/mips/macro-assembler-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 3911 matching lines @@
   Jump(stub->GetCode(isolate()), RelocInfo::CODE_TARGET);
 }
 
 
 static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
   return ref0.address() - ref1.address();
 }
 
 
 void MacroAssembler::CallApiFunctionAndReturn(ExternalReference function,
-                                              int stack_space) {
+                                              int stack_space,
+                                              bool returns_handle,
+                                              int return_value_offset_from_fp) {
   ExternalReference next_address =
       ExternalReference::handle_scope_next_address(isolate());
   const int kNextOffset = 0;
   const int kLimitOffset = AddressOffset(
       ExternalReference::handle_scope_limit_address(isolate()),
       next_address);
   const int kLevelOffset = AddressOffset(
       ExternalReference::handle_scope_level_address(isolate()),
       next_address);
 
@@ skipping 35 matching lines @@
     PopSafepointRegisters();
   }
 
   // As mentioned above, on MIPS a pointer is returned - we need to dereference
   // it to get the actual return value (which is also a pointer).
   lw(v0, MemOperand(v0));
 
   Label promote_scheduled_exception;
   Label delete_allocated_handles;
   Label leave_exit_frame;
+  Label return_value_loaded;
 
-  // If result is non-zero, dereference to get the result value
-  // otherwise set it to undefined.
-  Label skip;
-  LoadRoot(a0, Heap::kUndefinedValueRootIndex);
-  Branch(&skip, eq, v0, Operand(zero_reg));
-  lw(a0, MemOperand(v0));
-  bind(&skip);
-  mov(v0, a0);
+  if (returns_handle) {
+    Label load_return_value;
+    Branch(&load_return_value, eq, v0, Operand(zero_reg));
+    // Dereference returned value.
+    lw(v0, MemOperand(v0));
+    b(&return_value_loaded);
+    nop();
+    bind(&load_return_value);
+  }
+  // Load value from ReturnValue.
+  lw(v0, MemOperand(fp, return_value_offset_from_fp*kPointerSize));
+  bind(&return_value_loaded);
 
   // No more valid handles (the result handle was the last one). Restore
   // previous handle scope.
   sw(s0, MemOperand(s3, kNextOffset));
   if (emit_debug_code()) {
     lw(a1, MemOperand(s3, kLevelOffset));
     Check(eq, "Unexpected level after return from api call", a1, Operand(s2));
   }
   Subu(s2, s2, Operand(1));
   sw(s2, MemOperand(s3, kLevelOffset));
@@ skipping 1530 matching lines @@
        opcode == BGTZL);
   opcode = (cond == eq) ? BEQ : BNE;
   instr = (instr & ~kOpcodeMask) | opcode;
   masm_.emit(instr);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS