MIPS: Array constructor expects AllocationSite or undefined as feedback.

src/mips/code-stubs-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 3166 matching lines @@
     // Check that the function is really a JavaScript function.
     // a1: pushed function (to be verified)
     __ JumpIfSmi(a1, &non_function);
 
     // Goto slow case if we do not have a function.
     __ GetObjectType(a1, t0, t0);
     __ Branch(&slow, ne, t0, Operand(JS_FUNCTION_TYPE));
 
     if (RecordCallTarget()) {
       GenerateRecordCallTarget(masm);
+      // Type information was updated. Because we may call Array, which
+      // expects either undefined or an AllocationSite in a2 we need
+      // to set a2 to undefined.
+      __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
     }
   }
 
   // Fast-case: Invoke the function now.
   // a1: pushed function
   ParameterCount actual(argc_);
 
   if (CallAsMethod()) {
     if (NeedsChecks()) {
       // Do not transform the receiver for strict mode functions and natives.
@@ skipping 80 matching lines @@
   // a3 : (only if a2 is not undefined) slot in feedback vector (Smi)
   Label slow, non_function_call;
 
   // Check that the function is not a smi.
   __ JumpIfSmi(a1, &non_function_call);
   // Check that the function is a JSFunction.
   __ GetObjectType(a1, t0, t0);
   __ Branch(&slow, ne, t0, Operand(JS_FUNCTION_TYPE));
 
   if (RecordCallTarget()) {
+    Label feedback_register_initialized;
     GenerateRecordCallTarget(masm);
+
+    // Put the AllocationSite from the feedback vector into a2, or undefined.
+    __ sll(at, a3, kPointerSizeLog2 - kSmiTagSize);
+    __ Addu(t1, a2, at);
+    __ lw(a2, FieldMemOperand(t1, FixedArray::kHeaderSize));
+    __ lw(t1, FieldMemOperand(a2, AllocationSite::kMapOffset));
+    __ LoadRoot(at, Heap::kAllocationSiteMapRootIndex);
+    __ Branch(&feedback_register_initialized, eq, t1, Operand(at));
+    __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
+    __ bind(&feedback_register_initialized);
+    __ AssertUndefinedOrAllocationSite(a2, t1);
   }
 
   // Jump to the function-specific construct stub.
   Register jmp_reg = t0;
   __ lw(jmp_reg, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
   __ lw(jmp_reg, FieldMemOperand(jmp_reg,
                                  SharedFunctionInfo::kConstructStubOffset));
   __ Addu(at, jmp_reg, Operand(Code::kHeaderSize - kHeapObjectTag));
   __ Jump(at);
 
@@ skipping 2092 matching lines @@
   } else {
     UNREACHABLE();
   }
 }
 
 
 void ArrayConstructorStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- a0 : argc (only if argument_count_ == ANY)
   //  -- a1 : constructor
-  //  -- a2 : feedback vector (fixed array or megamorphic symbol)
-  //  -- a3 : slot index (if a2 is fixed array)
+  //  -- a2 : AllocationSite or undefined
   //  -- sp[0] : return address
   //  -- sp[4] : last argument
   // -----------------------------------
 
-  ASSERT_EQ(*TypeFeedbackInfo::MegamorphicSentinel(masm->isolate()),
-            masm->isolate()->heap()->megamorphic_symbol());
-
   if (FLAG_debug_code) {
     // The array construct code is only set for the global and natives
     // builtin Array functions which always have maps.
 
     // Initial map for the builtin Array function should be a map.
     __ lw(t0, FieldMemOperand(a1, JSFunction::kPrototypeOrInitialMapOffset));
     // Will both indicate a NULL and a Smi.
     __ SmiTst(t0, at);
     __ Assert(ne, kUnexpectedInitialMapForArrayFunction,
         at, Operand(zero_reg));
     __ GetObjectType(t0, t0, t1);
     __ Assert(eq, kUnexpectedInitialMapForArrayFunction,
         t1, Operand(MAP_TYPE));
 
-    // We should either have the megamorphic symbol in a2 or a valid
-    // fixed array.
-    Label okay_here;
-    Handle<Map> fixed_array_map = masm->isolate()->factory()->fixed_array_map();
-    __ LoadRoot(at, Heap::kMegamorphicSymbolRootIndex);
-    __ Branch(&okay_here, eq, a2, Operand(at));
-    __ lw(t0, FieldMemOperand(a2, 0));
-    __ Assert(eq, kExpectedFixedArrayInRegisterA2,
-        t0, Operand(fixed_array_map));
-
-    // a3 should be a smi if we don't have undefined in a2
-    __ AssertSmi(a3);
-
-    __ bind(&okay_here);
+    // We should either have undefined in a2 or a valid AllocationSite
+    __ AssertUndefinedOrAllocationSite(a2, t0);
   }
 
   Label no_info;
   // Get the elements kind and case on that.
-  __ LoadRoot(at, Heap::kMegamorphicSymbolRootIndex);
+  __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
   __ Branch(&no_info, eq, a2, Operand(at));
-  __ sll(t0, a3, kPointerSizeLog2 - kSmiTagSize);
-  __ Addu(a2, a2, Operand(t0));
-  __ lw(a2, FieldMemOperand(a2, FixedArray::kHeaderSize));
-
-  // If the feedback vector is undefined, or contains anything other than an
-  // AllocationSite, call an array constructor that doesn't use AllocationSites.
-  __ lw(t0, FieldMemOperand(a2, 0));
-  __ LoadRoot(at, Heap::kAllocationSiteMapRootIndex);
-  __ Branch(&no_info, ne, t0, Operand(at));
 
   __ lw(a3, FieldMemOperand(a2, AllocationSite::kTransitionInfoOffset));
   __ SmiUntag(a3);
   STATIC_ASSERT(AllocationSite::ElementsKindBits::kShift == 0);
   __ And(a3, a3, Operand(AllocationSite::ElementsKindBits::kMask));
   GenerateDispatchToArrayStub(masm, DONT_OVERRIDE);
 
   __ bind(&no_info);
   GenerateDispatchToArrayStub(masm, DISABLE_ALLOCATION_SITES);
 }
@@ skipping 214 matching lines @@
                               MemOperand(fp, 6 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS