[turbofan] Add support for String.prototype.charCodeAt/charAt.

src/compiler/access-builder.cc

 // Copyright 2014 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/compiler/access-builder.h"
 
 #include "src/contexts.h"
 #include "src/frames.h"
 #include "src/handles-inl.h"
 #include "src/heap/heap.h"
@@ skipping 368 matching lines @@
 FieldAccess AccessBuilder::ForStringLength() {
   FieldAccess access = {kTaggedBase,
                         String::kLengthOffset,
                         Handle<Name>(),
                         TypeCache::Get().kStringLengthType,
                         MachineType::AnyTagged(),
                         kNoWriteBarrier};
   return access;
 }
 
+// static
+FieldAccess AccessBuilder::ForConsStringFirst() {
+  FieldAccess access = {
+      kTaggedBase,    ConsString::kFirstOffset, Handle<Name>(),
+      Type::String(), MachineType::AnyTagged(), kPointerWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForConsStringSecond() {
+  FieldAccess access = {
+      kTaggedBase,    ConsString::kSecondOffset, Handle<Name>(),
+      Type::String(), MachineType::AnyTagged(),  kPointerWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForSlicedStringOffset() {
+  FieldAccess access = {
+      kTaggedBase,         SlicedString::kOffsetOffset, Handle<Name>(),
+      Type::SignedSmall(), MachineType::AnyTagged(),    kNoWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForSlicedStringParent() {
+  FieldAccess access = {
+      kTaggedBase,    SlicedString::kParentOffset, Handle<Name>(),
+      Type::String(), MachineType::AnyTagged(),    kPointerWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForExternalStringResourceData() {
+  FieldAccess access = {kTaggedBase,
+                        ExternalString::kResourceDataOffset,
+                        Handle<Name>(),
+                        Type::UntaggedPointer(),
+                        MachineType::Pointer(),
+                        kNoWriteBarrier};
+  return access;
+}
+
+// static
+ElementAccess AccessBuilder::ForExternalOneByteStringCharacter() {
+  ElementAccess access = {kUntaggedBase, 0, TypeCache::Get().kUint8,
+                          MachineType::Uint8(), kNoWriteBarrier};
+  return access;
+}
+
+// static
+ElementAccess AccessBuilder::ForExternalTwoByteStringCharacter() {
+  ElementAccess access = {kUntaggedBase, 0, TypeCache::Get().kUint16,
+                          MachineType::Uint16(), kNoWriteBarrier};
+  return access;
+}
+
+// static
+ElementAccess AccessBuilder::ForSeqOneByteStringCharacter() {
+  ElementAccess access = {kTaggedBase, SeqOneByteString::kHeaderSize,
+                          TypeCache::Get().kUint8, MachineType::Uint8(),
+                          kNoWriteBarrier};
+  return access;
+}
+
+// static
+ElementAccess AccessBuilder::ForSeqTwoByteStringCharacter() {
+  ElementAccess access = {kTaggedBase, SeqTwoByteString::kHeaderSize,
+                          TypeCache::Get().kUint16, MachineType::Uint16(),
+                          kNoWriteBarrier};
+  return access;
+}
 
 // static
 FieldAccess AccessBuilder::ForJSGlobalObjectGlobalProxy() {
   FieldAccess access = {kTaggedBase,
                         JSGlobalObject::kGlobalProxyOffset,
                         Handle<Name>(),
                         Type::Receiver(),
                         MachineType::AnyTagged(),
                         kPointerWriteBarrier};
   return access;
 }
 
-
 // static
 FieldAccess AccessBuilder::ForJSGlobalObjectNativeContext() {
   FieldAccess access = {kTaggedBase,
                         JSGlobalObject::kNativeContextOffset,
                         Handle<Name>(),
                         Type::Internal(),
                         MachineType::AnyTagged(),
                         kPointerWriteBarrier};
   return access;
 }
@@ skipping 138 matching lines @@
   }
   UNREACHABLE();
   ElementAccess access = {kUntaggedBase, 0, Type::None(), MachineType::None(),
                           kNoWriteBarrier};
   return access;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8