VM: Optimized code for all of [External]{One|Two}ByteString::codeUnitAt.

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 "vm/compiler.h"
@@ skipping 822 matching lines @@
     return false;
   }
   const int64_t index = Smi::Cast(constant->value()).AsInt64Value();
   const intptr_t scale = Instance::ElementSizeFor(cid);
   const intptr_t offset = Instance::DataOffsetFor(cid);
   const int64_t displacement = index * scale + offset;
   return Utils::IsInt(32, displacement);
 }
 
 
-LocationSummary* StringFromCharCodeInstr::MakeLocationSummary(Zone* zone,
-                                                              bool opt) const {
+LocationSummary* OneByteStringFromCharCodeInstr::MakeLocationSummary(
+    Zone* zone, bool opt) const {
   const intptr_t kNumInputs = 1;
   // TODO(fschneider): Allow immediate operands for the char code.
   return LocationSummary::Make(zone,
                                kNumInputs,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
-void StringFromCharCodeInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+void OneByteStringFromCharCodeInstr::EmitNativeCode(
+    FlowGraphCompiler* compiler) {
   Register char_code = locs()->in(0).reg();
   Register result = locs()->out(0).reg();
   __ movl(result,
           Immediate(reinterpret_cast<uword>(Symbols::PredefinedAddress())));
   __ movl(result, Address(result,
                           char_code,
                           TIMES_HALF_WORD_SIZE,  // Char code is a smi.
                           Symbols::kNullCharCodeSymbolOffset * kWordSize));
 }
 
@@ skipping 128 matching lines @@
 
     case kTypedDataInt8ArrayCid:
     case kTypedDataUint8ArrayCid:
     case kTypedDataUint8ClampedArrayCid:
     case kExternalTypedDataUint8ArrayCid:
     case kExternalTypedDataUint8ClampedArrayCid:
     case kTypedDataInt16ArrayCid:
     case kTypedDataUint16ArrayCid:
     case kOneByteStringCid:
     case kTwoByteStringCid:
+    case kExternalOneByteStringCid:
+    case kExternalTwoByteStringCid:
       return CompileType::FromCid(kSmiCid);
 
     case kTypedDataInt32ArrayCid:
     case kTypedDataUint32ArrayCid:
       return CompileType::Int();
 
     default:
       UNIMPLEMENTED();
       return CompileType::Dynamic();
   }
 }
 
 
 Representation LoadIndexedInstr::representation() const {
   switch (class_id_) {
     case kArrayCid:
     case kImmutableArrayCid:
     case kTypedDataInt8ArrayCid:
     case kTypedDataUint8ArrayCid:
     case kTypedDataUint8ClampedArrayCid:
     case kExternalTypedDataUint8ArrayCid:
     case kExternalTypedDataUint8ClampedArrayCid:
     case kTypedDataInt16ArrayCid:
     case kTypedDataUint16ArrayCid:
     case kOneByteStringCid:
     case kTwoByteStringCid:
+    case kExternalOneByteStringCid:
+    case kExternalTwoByteStringCid:
       return kTagged;
     case kTypedDataInt32ArrayCid:
       return kUnboxedInt32;
     case kTypedDataUint32ArrayCid:
       return kUnboxedUint32;
     case kTypedDataFloat32ArrayCid:
     case kTypedDataFloat64ArrayCid:
       return kUnboxedDouble;
     case kTypedDataFloat32x4ArrayCid:
       return kUnboxedFloat32x4;
@@ skipping 113 matching lines @@
     case kTypedDataInt8ArrayCid:
       ASSERT(index_scale() == 1);
       __ movsxb(result, element_address);
       __ SmiTag(result);
       break;
     case kTypedDataUint8ArrayCid:
     case kTypedDataUint8ClampedArrayCid:
     case kExternalTypedDataUint8ArrayCid:
     case kExternalTypedDataUint8ClampedArrayCid:
     case kOneByteStringCid:
+    case kExternalOneByteStringCid:
       ASSERT(index_scale() == 1);
       __ movzxb(result, element_address);
       __ SmiTag(result);
       break;
     case kTypedDataInt16ArrayCid:
       __ movsxw(result, element_address);
       __ SmiTag(result);
       break;
     case kTypedDataUint16ArrayCid:
     case kTwoByteStringCid:
+    case kExternalTwoByteStringCid:
       __ movzxw(result, element_address);
       __ SmiTag(result);
       break;
     default:
       ASSERT((class_id() == kArrayCid) || (class_id() == kImmutableArrayCid));
       __ movl(result, element_address);
       break;
   }
 }
 
@@ skipping 5684 matching lines @@
   __ Drop(1);
   __ popl(result);
 }
 
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_IA32