Make KeyedStores from a sloppy arguments array use a handler.

src/code-stubs-hydrogen.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"
 
 #include "src/bailout-reason.h"
 #include "src/code-stubs.h"
 #include "src/field-index.h"
 #include "src/hydrogen.h"
@@ skipping 56 matching lines @@
   void BuildStoreNamedField(HValue* object, HValue* value, FieldIndex index,
                             Representation representation,
                             bool transition_to_field);
 
   enum ArgumentClass {
     NONE,
     SINGLE,
     MULTIPLE
   };
 
-  HValue* UnmappedCase(HValue* elements, HValue* key);
+  HValue* UnmappedCase(HValue* elements, HValue* key, HValue* value);
+  HValue* EmitKeyedSloppyArguments(HValue* receiver, HValue* key,
+                                   HValue* value);
 
   HValue* BuildArrayConstructor(ElementsKind kind,
                                 AllocationSiteOverrideMode override_mode,
                                 ArgumentClass argument_class);
   HValue* BuildInternalArrayConstructor(ElementsKind kind,
                                         ArgumentClass argument_class);
 
   // BuildCheckAndInstallOptimizedCode emits code to install the optimized
   // function found in the optimized code map at map_index in js_function, if
   // the function at map_index matches the given native_context. Builder is
@@ skipping 701 matching lines @@
   HValue* descriptors = Add<HLoadNamedField>(map, nullptr, descriptors_access);
   HObjectAccess value_access = HObjectAccess::ForObservableJSObjectOffset(
       DescriptorArray::GetValueOffset(casted_stub()->constant_index()));
   return Add<HLoadNamedField>(descriptors, nullptr, value_access);
 }
 
 
 Handle<Code> LoadConstantStub::GenerateCode() { return DoGenerateCode(this); }
 
 
-HValue* CodeStubGraphBuilderBase::UnmappedCase(HValue* elements, HValue* key) {
-  HValue* result;
+HValue* CodeStubGraphBuilderBase::UnmappedCase(HValue* elements, HValue* key,
+                                               HValue* value) {
+  HValue* result = NULL;
   HInstruction* backing_store =
       Add<HLoadKeyed>(elements, graph()->GetConstant1(), nullptr, FAST_ELEMENTS,
                       ALLOW_RETURN_HOLE);
   Add<HCheckMaps>(backing_store, isolate()->factory()->fixed_array_map());
   HValue* backing_store_length = Add<HLoadNamedField>(
       backing_store, nullptr, HObjectAccess::ForFixedArrayLength());
   IfBuilder in_unmapped_range(this);
   in_unmapped_range.If<HCompareNumericAndBranch>(key, backing_store_length,
                                                  Token::LT);
   in_unmapped_range.Then();
   {
-    result = Add<HLoadKeyed>(backing_store, key, nullptr, FAST_HOLEY_ELEMENTS,
-                             NEVER_RETURN_HOLE);
+    if (value == NULL) {
+      result = Add<HLoadKeyed>(backing_store, key, nullptr, FAST_HOLEY_ELEMENTS,
+                               NEVER_RETURN_HOLE);
+    } else {
+      Add<HStoreKeyed>(backing_store, key, value, FAST_HOLEY_ELEMENTS);
+    }
   }
   in_unmapped_range.ElseDeopt(Deoptimizer::kOutsideOfRange);
   in_unmapped_range.End();
   return result;
 }
 
 
-template <>
-HValue* CodeStubGraphBuilder<KeyedLoadSloppyArgumentsStub>::BuildCodeStub() {
-  HValue* receiver = GetParameter(LoadDescriptor::kReceiverIndex);
-  HValue* key = GetParameter(LoadDescriptor::kNameIndex);
-
+HValue* CodeStubGraphBuilderBase::EmitKeyedSloppyArguments(HValue* receiver,
+                                                           HValue* key,
+                                                           HValue* value) {
   // Mapped arguments are actual arguments. Unmapped arguments are values added
   // to the arguments object after it was created for the call. Mapped arguments
   // are stored in the context at indexes given by elements[key + 2]. Unmapped
   // arguments are stored as regular indexed properties in the arguments array,
   // held at elements[1]. See NewSloppyArguments() in runtime.cc for a detailed
   // look at argument object construction.
   //
   // The sloppy arguments elements array has a special format:
   //
   // 0: context
   // 1: unmapped arguments array
   // 2: mapped_index0,
   // 3: mapped_index1,
   // ...
   //
   // length is 2 + min(number_of_actual_arguments, number_of_formal_arguments).
   // If key + 2 >= elements.length then attempt to look in the unmapped
   // arguments array (given by elements[1]) and return the value at key, missing
   // to the runtime if the unmapped arguments array is not a fixed array or if
   // key >= unmapped_arguments_array.length.
   //
   // Otherwise, t = elements[key + 2]. If t is the hole, then look up the value
   // in the unmapped arguments array, as described above. Otherwise, t is a Smi
   // index into the context array given at elements[0]. Return the value at
   // context[t].
 
+  bool is_load = value == NULL;
+
   key = AddUncasted<HForceRepresentation>(key, Representation::Smi());
   IfBuilder positive_smi(this);
   positive_smi.If<HCompareNumericAndBranch>(key, graph()->GetConstant0(),
                                             Token::LT);
   positive_smi.ThenDeopt(Deoptimizer::kKeyIsNegative);
   positive_smi.End();
 
   HValue* constant_two = Add<HConstant>(2);
   HValue* elements = AddLoadElements(receiver, nullptr);
   HValue* elements_length = Add<HLoadNamedField>(
@@ skipping 11 matching lines @@
     is_valid.IfNot<HCompareObjectEqAndBranch>(mapped_index,
                                               graph()->GetConstantHole());
     is_valid.Then();
     {
       // TODO(mvstanton): I'd like to assert from this point, that if the
       // mapped_index is not the hole that it is indeed, a smi. An unnecessary
       // smi check is being emitted.
       HValue* the_context = Add<HLoadKeyed>(elements, graph()->GetConstant0(),
                                             nullptr, FAST_ELEMENTS);
       STATIC_ASSERT(Context::kHeaderSize == FixedArray::kHeaderSize);
-      HValue* result = Add<HLoadKeyed>(the_context, mapped_index, nullptr,
-                                       FAST_ELEMENTS, ALLOW_RETURN_HOLE);
-      environment()->Push(result);
+      if (is_load) {
+        HValue* result = Add<HLoadKeyed>(the_context, mapped_index, nullptr,
+                                         FAST_ELEMENTS, ALLOW_RETURN_HOLE);
+        environment()->Push(result);
+      } else {
+        DCHECK(value != NULL);
+        Add<HStoreKeyed>(the_context, mapped_index, value, FAST_ELEMENTS);
+        environment()->Push(value);
+      }
     }
     is_valid.Else();
     {
-      HValue* result = UnmappedCase(elements, key);
-      environment()->Push(result);
+      HValue* result = UnmappedCase(elements, key, value);
+      environment()->Push(is_load ? result : value);
     }
     is_valid.End();
   }
   in_range.Else();
   {
-    HValue* result = UnmappedCase(elements, key);
-    environment()->Push(result);
+    HValue* result = UnmappedCase(elements, key, value);
+    environment()->Push(is_load ? result : value);
   }
   in_range.End();
 
   return environment()->Pop();
 }
 
 
+template <>
+HValue* CodeStubGraphBuilder<KeyedLoadSloppyArgumentsStub>::BuildCodeStub() {
+  HValue* receiver = GetParameter(LoadDescriptor::kReceiverIndex);
+  HValue* key = GetParameter(LoadDescriptor::kNameIndex);
+
+  return EmitKeyedSloppyArguments(receiver, key, NULL);
+}
+
+
 Handle<Code> KeyedLoadSloppyArgumentsStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
+template <>
+HValue* CodeStubGraphBuilder<KeyedStoreSloppyArgumentsStub>::BuildCodeStub() {
+  HValue* receiver = GetParameter(StoreDescriptor::kReceiverIndex);
+  HValue* key = GetParameter(StoreDescriptor::kNameIndex);
+  HValue* value = GetParameter(StoreDescriptor::kValueIndex);
+
+  return EmitKeyedSloppyArguments(receiver, key, value);
+}
+
+
+Handle<Code> KeyedStoreSloppyArgumentsStub::GenerateCode() {
+  return DoGenerateCode(this);
+}
+
+
 void CodeStubGraphBuilderBase::BuildStoreNamedField(
     HValue* object, HValue* value, FieldIndex index,
     Representation representation, bool transition_to_field) {
   DCHECK(!index.is_double() || representation.IsDouble());
   int offset = index.offset();
   HObjectAccess access =
       index.is_inobject()
           ? HObjectAccess::ForObservableJSObjectOffset(offset, representation)
           : HObjectAccess::ForBackingStoreOffset(offset, representation);
 
@@ skipping 1279 matching lines @@
 
   return Pop();
 }
 
 
 Handle<Code> KeyedLoadGenericStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 } }  // namespace v8::internal