Support loads from Uint8Array and ExternalUint8Array in the optimizing compiler.

runtime/vm/intermediate_language_ia32.cc

 // Copyright (c) 2012, 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 1151 matching lines @@
   } else {
     locs->set_out(Location::RequiresRegister());
   }
   return locs;
 }
 
 
 void LoadIndexedInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register array = locs()->in(0).reg();
   Location index = locs()->in(1);
+
+  if (class_id() == kExternalUint8ArrayCid) {
+    Register result = locs()->out().reg();
+    Address element_address = index.IsRegister()
+        ? Address(result, index.reg(), TIMES_1, 0)
+        : Address(result, Smi::Cast(index.constant()).Value());
+    if (index.IsRegister()) {
+      __ SmiUntag(index.reg());
+    }
+    __ movl(result,
+            FieldAddress(array, ExternalUint8Array::external_data_offset()));
+    __ movl(result,
+            Address(result, ExternalByteArrayData<uint8_t>::data_offset()));
+    __ movzxb(result, element_address);
+    __ SmiTag(result);
+    if (index.IsRegister()) {
+      __ SmiTag(index.reg());  // Re-tag.
+    }
+    return;
+  }
+
   FieldAddress element_address = index.IsRegister() ?
       FlowGraphCompiler::ElementAddressForRegIndex(
           class_id(), array, index.reg()) :
       FlowGraphCompiler::ElementAddressForIntIndex(
           class_id(), array, Smi::Cast(index.constant()).Value());
 
   if (representation() == kUnboxedDouble) {
+    XmmRegister result = locs()->out().xmm_reg();
     if (class_id() == kFloat32ArrayCid) {
       // Load single precision float.
-      __ movss(locs()->out().xmm_reg(), element_address);
+      __ movss(result, element_address);
       // Promote to double.
-      __ cvtss2sd(locs()->out().xmm_reg(), locs()->out().xmm_reg());
+      __ cvtss2sd(result, locs()->out().xmm_reg());
     } else {
       ASSERT(class_id() == kFloat64ArrayCid);
-      __ movsd(locs()->out().xmm_reg(), element_address);
+      __ movsd(result, element_address);
     }
+    return;
+  }
+
+  Register result = locs()->out().reg();
+  if (class_id() == kUint8ArrayCid) {
+      if (index.IsRegister()) {
+        __ SmiUntag(index.reg());
+      }
+      __ movzxb(result, element_address);
+      __ SmiTag(result);
+      if (index.IsRegister()) {
+        __ SmiTag(index.reg());  // Re-tag.
+      }

[srdjan, 2012/11/22 18:18:19]

To be similar to cases above, you could do a return here as well.

[Florian Schneider, 2012/11/23 14:49:39]

Done.

   } else {
-    __ movl(locs()->out().reg(), element_address);
+    ASSERT((class_id() == kArrayCid) || (class_id() == kImmutableArrayCid));
+    __ movl(result, element_address);
   }
 }
 
 
 LocationSummary* StoreIndexedInstr::MakeLocationSummary() const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = class_id() == kFloat32ArrayCid ? 1 : 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   if (class_id() == kFloat32ArrayCid) {
@@ skipping 31 matching lines @@
     // Store.
     __ movss(element_address, locs()->temp(0).xmm_reg());
     return;
   }
 
   if (class_id() == kFloat64ArrayCid) {
     __ movsd(element_address, locs()->in(2).xmm_reg());
     return;
   }
 
+  ASSERT(class_id() == kArrayCid);
   if (ShouldEmitStoreBarrier()) {
     Register value = locs()->in(2).reg();
     __ StoreIntoObject(array, element_address, value);
     return;
   }
 
   if (locs()->in(2).IsConstant()) {
     const Object& constant = locs()->in(2).constant();
     __ StoreIntoObjectNoBarrier(array, element_address, constant);
   } else {
@@ skipping 1501 matching lines @@
   __ pcmpeqq(XMM0, XMM0);  // Generate all 1's.
   __ pxor(value, XMM0);
 }
 
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64