Remove unnecessary environment from LStoreKeyedFastElements.

src/hydrogen.cc

 // Copyright 2011 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 3495 matching lines @@
 
     elements = new(zone()) HLoadElements(literal);
     AddInstruction(elements);
 
     HValue* key = AddInstruction(
         new(zone()) HConstant(Handle<Object>(Smi::FromInt(i)),
                               Representation::Integer32()));
 
     switch (boilerplate_elements_kind) {
       case FAST_SMI_ONLY_ELEMENTS:
+        // Smi-only arrays need a smi check.
+        AddInstruction(new(zone()) HCheckSmi(value));
+        // Fall through.
       case FAST_ELEMENTS:
         AddInstruction(new(zone()) HStoreKeyedFastElement(
             elements,
             key,
             value,
             boilerplate_elements_kind));
         break;
       case FAST_DOUBLE_ELEMENTS:
         AddInstruction(new(zone()) HStoreKeyedFastDoubleElement(elements,
                                                                 key,
@@ skipping 690 matching lines @@
 }
 
 
 HInstruction* HGraphBuilder::BuildFastElementAccess(HValue* elements,
                                                     HValue* checked_key,
                                                     HValue* val,
                                                     ElementsKind elements_kind,
                                                     bool is_store) {
   if (is_store) {
     ASSERT(val != NULL);
-    if (elements_kind == FAST_DOUBLE_ELEMENTS) {
-      return new(zone()) HStoreKeyedFastDoubleElement(
-          elements, checked_key, val);
-    } else {  // FAST_ELEMENTS or FAST_SMI_ONLY_ELEMENTS.
-      return new(zone()) HStoreKeyedFastElement(
-          elements, checked_key, val, elements_kind);
+    switch (elements_kind) {
+      case FAST_DOUBLE_ELEMENTS:
+        return new(zone()) HStoreKeyedFastDoubleElement(
+            elements, checked_key, val);
+      case FAST_SMI_ONLY_ELEMENTS:
+        // Smi-only arrays need a smi check.
+        AddInstruction(new(zone()) HCheckSmi(val));
+        // Fall through.
+      case FAST_ELEMENTS:
+        return new(zone()) HStoreKeyedFastElement(
+            elements, checked_key, val, elements_kind);
+      default:
+        UNREACHABLE();
+        return NULL;
     }
   }
   // It's an element load (!is_store).
   if (elements_kind == FAST_DOUBLE_ELEMENTS) {
     return new(zone()) HLoadKeyedFastDoubleElement(elements, checked_key);
   } else {  // FAST_ELEMENTS or FAST_SMI_ONLY_ELEMENTS.
     return new(zone()) HLoadKeyedFastElement(elements, checked_key);
   }
 }
 
@@ skipping 150 matching lines @@
           elements_kind_instr, elements_kind, Token::EQ_STRICT);
       elements_kind_branch->SetSuccessorAt(0, if_true);
       elements_kind_branch->SetSuccessorAt(1, if_false);
       current_block()->Finish(elements_kind_branch);
 
       set_current_block(if_true);
       HInstruction* access;
       if (elements_kind == FAST_SMI_ONLY_ELEMENTS ||
           elements_kind == FAST_ELEMENTS ||
           elements_kind == FAST_DOUBLE_ELEMENTS) {
-        if (is_store && elements_kind == FAST_SMI_ONLY_ELEMENTS) {
-          AddInstruction(new(zone()) HCheckSmi(val));

[fschneider, 2011/12/22 16:00:03]

This check becomes redundant because there is now one generated in
BuildFastElementAccess.

-        }
         if (is_store && elements_kind != FAST_DOUBLE_ELEMENTS) {
           AddInstruction(new(zone()) HCheckMap(
               elements, isolate()->factory()->fixed_array_map(),
               elements_kind_branch));
         }
         // TODO(jkummerow): The need for these two blocks could be avoided
         // in one of two ways:
         // (1) Introduce ElementsKinds for JSArrays that are distinct from
         //     those for fast objects.
         // (2) Put the common instructions into a third "join" block. This
@@ skipping 2888 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal