Optimize stores to ExternalUint8Array and ExternalUint8ClampedArray in the optimizer.

runtime/vm/intermediate_language_ia32.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_IA32.
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 1287 matching lines @@
 
 
 Representation StoreIndexedInstr::RequiredInputRepresentation(
     intptr_t idx) const {
   if ((idx == 0) || (idx == 1)) return kTagged;
   ASSERT(idx == 2);
   switch (class_id_) {
     case kArrayCid:
     case kInt8ArrayCid:
     case kUint8ArrayCid:
+    case kExternalUint8ArrayCid:
     case kUint8ClampedArrayCid:
+    case kExternalUint8ClampedArrayCid:
     case kInt16ArrayCid:
     case kUint16ArrayCid:
       return kTagged;
     case kInt32ArrayCid:
     case kUint32ArrayCid:
       return kUnboxedMint;
     case kFloat32ArrayCid :
     case kFloat64ArrayCid :
       return kUnboxedDouble;
     default:
@@ skipping 14 matching lines @@
   // sizes > 1).
   locs->set_in(1, CanBeImmediateIndex(index(), class_id())
                     ? Location::RegisterOrSmiConstant(index())
                     : Location::RequiresRegister());
   switch (class_id()) {
     case kArrayCid:
       locs->set_in(2, ShouldEmitStoreBarrier()
                         ? Location::WritableRegister()
                         : Location::RegisterOrConstant(value()));
       break;
+    case kExternalUint8ArrayCid:
+    case kExternalUint8ClampedArrayCid:
+      // Need temp register to load the external array's data array.
+      locs->AddTemp(Location::RequiresRegister());
+      // Fall through.
     case kInt8ArrayCid:
     case kUint8ArrayCid:
     case kUint8ClampedArrayCid:
       // TODO(fschneider): Add location constraint for byte registers (EAX,
       // EBX, ECX, EDX) instead of using a fixed register.
       locs->set_in(2, Location::FixedRegisterOrSmiConstant(value(), EAX));
       break;
     case kInt16ArrayCid:
     case kUint16ArrayCid:
       // Writable register because the value must be untagged before storing.
@@ skipping 16 matching lines @@
   return locs;
 }
 
 
 void StoreIndexedInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register array = locs()->in(0).reg();
   Location index = locs()->in(1);
 
   intptr_t index_scale = FlowGraphCompiler::ElementSizeFor(class_id());
 
-  FieldAddress element_address = index.IsRegister() ?
-      FlowGraphCompiler::ElementAddressForRegIndex(
-          class_id(), index_scale, array, index.reg()) :
-      FlowGraphCompiler::ElementAddressForIntIndex(
+  Address element_address(kNoRegister, 0);
+  if ((class_id() == kExternalUint8ArrayCid) ||
+      (class_id() == kExternalUint8ClampedArrayCid)) {
+    Register temp = locs()->temp(0).reg();
+    element_address = index.IsRegister()
+        ? FlowGraphCompiler::ExternalElementAddressForRegIndex(
+            class_id(), index_scale, temp, index.reg())
+        : FlowGraphCompiler::ExternalElementAddressForIntIndex(
+            class_id(), index_scale, temp,
+            Smi::Cast(index.constant()).Value());
+    __ movl(temp,
+            FieldAddress(array, ExternalUint8Array::data_offset()));
+  } else {
+    element_address = index.IsRegister()
+        ? FlowGraphCompiler::ElementAddressForRegIndex(
+          class_id(), index_scale, array, index.reg())
+        : FlowGraphCompiler::ElementAddressForIntIndex(
           class_id(), index_scale, array, Smi::Cast(index.constant()).Value());
+  }
 
   switch (class_id()) {
     case kArrayCid:
       if (ShouldEmitStoreBarrier()) {
         Register value = locs()->in(2).reg();
         __ StoreIntoObject(array, element_address, value);
       } else if (locs()->in(2).IsConstant()) {
         const Object& constant = locs()->in(2).constant();
         __ StoreIntoObjectNoBarrier(array, element_address, constant);
       } else {
         Register value = locs()->in(2).reg();
         __ StoreIntoObjectNoBarrier(array, element_address, value);
       }
       break;
     case kInt8ArrayCid:
     case kUint8ArrayCid:
+    case kExternalUint8ArrayCid:
       if (index.IsRegister()) {
         __ SmiUntag(index.reg());
       }
       if (locs()->in(2).IsConstant()) {
         const Smi& constant = Smi::Cast(locs()->in(2).constant());
         __ movb(element_address,
                 Immediate(static_cast<int8_t>(constant.Value())));
       } else {
         ASSERT(locs()->in(2).reg() == EAX);
         __ SmiUntag(EAX);
         __ movb(element_address, AL);
       }
       if (index.IsRegister()) {
         __ SmiTag(index.reg());  // Re-tag.
       }
       break;
-    case kUint8ClampedArrayCid: {
+    case kUint8ClampedArrayCid:
+    case kExternalUint8ClampedArrayCid: {
       if (index.IsRegister()) {
         __ SmiUntag(index.reg());
       }
       if (locs()->in(2).IsConstant()) {
         const Smi& constant = Smi::Cast(locs()->in(2).constant());
         intptr_t value = constant.Value();
         // Clamp to 0x0 or 0xFF respectively.
         if (value > 0xFF) {
           value = 0xFF;
         } else if (value < 0) {
@@ skipping 1990 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(2);  // Discard type arguments and receiver.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_IA32