Fix memento initialization when constructing from new call

src/mips64/builtins-mips64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS64
 
@@ skipping 318 matching lines @@
 
   // Should never create mementos for api functions.
   DCHECK(!is_api_function || !create_memento);
 
   Isolate* isolate = masm->isolate();
 
   // Enter a construct frame.
   {
     FrameScope scope(masm, StackFrame::CONSTRUCT);
 
-    if (create_memento) {
-      __ AssertUndefinedOrAllocationSite(a2, t0);
-      __ push(a2);
-    }
-
     // Preserve the incoming parameters on the stack.
+    __ AssertUndefinedOrAllocationSite(a2, t0);
+    __ push(a2);

[Michael Starzinger, 2015/07/16 15:40:12]

Multiple pushes seem to be going on here, I think this line is bogus.

[Michael Lippautz, 2015/07/16 16:55:12]

whoops, done.

     __ SmiTag(a0);
-    __ Push(a0, a1, a3);
+    __ Push(a2, a0, a1, a3);
 
     // Try to allocate the object without transitioning into C code. If any of
     // the preconditions is not met, the code bails out to the runtime call.
     Label rt_call, allocated;
     if (FLAG_inline_new) {
       ExternalReference debug_step_in_fp =
           ExternalReference::debug_step_in_fp_address(isolate);
       __ li(a2, Operand(debug_step_in_fp));
       __ ld(a2, MemOperand(a2));
       __ Branch(&rt_call, ne, a2, Operand(zero_reg));
@@ skipping 112 matching lines @@
         __ Daddu(a0, t0, Operand(a0));  // End of object.
         __ InitializeFieldsWithFiller(t1, a0, t3);
 
         // Fill in memento fields.
         // t1: points to the allocated but uninitialized memento.
         __ LoadRoot(t3, Heap::kAllocationMementoMapRootIndex);
         DCHECK_EQ(0 * kPointerSize, AllocationMemento::kMapOffset);
         __ sd(t3, MemOperand(t1));
         __ Daddu(t1, t1, kPointerSize);
         // Load the AllocationSite.
-        __ ld(t3, MemOperand(sp, 2 * kPointerSize));
+        __ ld(t3, MemOperand(sp, 3 * kPointerSize));
+        __ AssertUndefinedOrAllocationSite(t3, t0);

[Michael Starzinger, 2015/07/16 15:40:12]

This will clobber t0, which contains the untagged JSObject at this point, you
should be able to use a0 here.

[Michael Lippautz, 2015/07/16 16:55:12]

Done.

         DCHECK_EQ(1 * kPointerSize, AllocationMemento::kAllocationSiteOffset);
         __ sd(t3, MemOperand(t1));
         __ Daddu(t1, t1, kPointerSize);
       } else {
         __ dsll(at, a3, kPointerSizeLog2);
         __ Daddu(a0, t0, Operand(at));  // End of object.
         __ InitializeFieldsWithFiller(t1, a0, t3);
       }
 
       // Add the object tag to make the JSObject real, so that we can continue
@@ skipping 161 matching lines @@
 void Builtins::Generate_JSConstructStubForDerived(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- a0     : number of arguments
   //  -- a1     : constructor function
   //  -- a2     : allocation site or undefined
   //  -- a3     : original constructor
   //  -- ra     : return address
   //  -- sp[...]: constructor arguments
   // -----------------------------------
 
-  // TODO(dslomov): support pretenuring
-  CHECK(!FLAG_pretenuring_call_new);
-
   {
     FrameScope frame_scope(masm, StackFrame::CONSTRUCT);
 
+    __ AssertUndefinedOrAllocationSite(a2, t0);
+    __ push(a2);
+
     __ mov(a4, a0);
     __ SmiTag(a4);
     __ push(a4);  // Smi-tagged arguments count.
 
     // Push new.target.
     __ push(a3);
 
     // receiver is the hole.
     __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
     __ push(at);
@@ skipping 1059 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64