[turbofan] Structure AccessBuilder interface a bit.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1178103002

Cr-Commit-Position: refs/heads/master@{#28940}

src/compiler/access-builder.cc

@@ -37,6 +37,13 @@ FieldAccess AccessBuilder::ForJSFunctionContext() {
 }
 
 
+// static
+FieldAccess AccessBuilder::ForJSFunctionSharedFunctionInfo() {
+  return {kTaggedBase, JSFunction::kSharedFunctionInfoOffset, Handle<Name>(),
+          Type::Any(), kMachAnyTagged};
+}
+
+
 // static
 FieldAccess AccessBuilder::ForJSArrayBufferBackingStore() {
   return {kTaggedBase, JSArrayBuffer::kBackingStoreOffset, MaybeHandle<Name>(),
@@ -129,15 +136,16 @@ FieldAccess AccessBuilder::ForContextSlot(size_t index) {
 
 
 // static
-FieldAccess AccessBuilder::ForStatsCounter() {
-  return {kUntaggedBase, 0, MaybeHandle<Name>(), Type::Signed32(), kMachInt32};
+FieldAccess AccessBuilder::ForPropertyCellValue() {
+  return {kTaggedBase, PropertyCell::kValueOffset, Handle<Name>(), Type::Any(),
+          kMachAnyTagged};
 }
 
 
 // static
-FieldAccess AccessBuilder::ForPropertyCellValue() {
-  return {kTaggedBase, PropertyCell::kValueOffset, Handle<Name>(), Type::Any(),
-          kMachAnyTagged};
+FieldAccess AccessBuilder::ForSharedFunctionInfoTypeFeedbackVector() {
+  return {kTaggedBase, SharedFunctionInfo::kFeedbackVectorOffset,
+          Handle<Name>(), Type::Any(), kMachAnyTagged};
 }
 
 
@@ -192,16 +200,8 @@ ElementAccess AccessBuilder::ForSeqStringChar(String::Encoding encoding) {
 
 
 // static
-FieldAccess AccessBuilder::ForJSFunctionSharedFunctionInfo() {
-  return {kTaggedBase, JSFunction::kSharedFunctionInfoOffset, Handle<Name>(),
-          Type::Any(), kMachAnyTagged};
-}
-
-
-// static
-FieldAccess AccessBuilder::ForSharedFunctionInfoTypeFeedbackVector() {
-  return {kTaggedBase, SharedFunctionInfo::kFeedbackVectorOffset,
-          Handle<Name>(), Type::Any(), kMachAnyTagged};
+FieldAccess AccessBuilder::ForStatsCounter() {
+  return {kUntaggedBase, 0, MaybeHandle<Name>(), Type::Signed32(), kMachInt32};
 }
 
 

src/compiler/access-builder.h

@@ -16,6 +16,9 @@ namespace compiler {
 // parameters to simplified load/store operators.
 class AccessBuilder final : public AllStatic {
  public:
+  // ===========================================================================
+  // Access to heap object fields and elements (based on tagged pointer).
+
   // Provides access to HeapObject::map() field.
   static FieldAccess ForMap();
 
@@ -28,6 +31,9 @@ class AccessBuilder final : public AllStatic {
   // Provides access to JSFunction::context() field.
   static FieldAccess ForJSFunctionContext();
 
+  // Provides access to JSFunction::shared() field.
+  static FieldAccess ForJSFunctionSharedFunctionInfo();
+
   // Provides access to JSArrayBuffer::backing_store() field.
   static FieldAccess ForJSArrayBufferBackingStore();
 
@@ -64,12 +70,12 @@ class AccessBuilder final : public AllStatic {
   // Provides access Context slots.
   static FieldAccess ForContextSlot(size_t index);
 
-  // Provides access to the backing store of a StatsCounter.
-  static FieldAccess ForStatsCounter();
-
   // Provides access to PropertyCell::value() field.
   static FieldAccess ForPropertyCellValue();
 
+  // Provides access to SharedFunctionInfo::feedback_vector() field.
+  static FieldAccess ForSharedFunctionInfoTypeFeedbackVector();
+
   // Provides access to FixedArray elements.
   static ElementAccess ForFixedArrayElement();
 
@@ -77,14 +83,17 @@ class AccessBuilder final : public AllStatic {
   static ElementAccess ForTypedArrayElement(ExternalArrayType type,
                                             bool is_external);
 
-  // Provides access to the charaters of sequential strings.
+  // Provides access to the characters of sequential strings.
   static ElementAccess ForSeqStringChar(String::Encoding encoding);
 
-  // Provides access to the SharedFunctionInfo in a JSFunction.
-  static FieldAccess ForJSFunctionSharedFunctionInfo();
+  // ===========================================================================
+  // Access to global per-isolate variables (based on external reference).
 
-  // Provides access to the TypeFeedbackVector in SharedFunctionInfo.
-  static FieldAccess ForSharedFunctionInfoTypeFeedbackVector();
+  // Provides access to the backing store of a StatsCounter.
+  static FieldAccess ForStatsCounter();
+
+  // ===========================================================================
+  // Access to activation records on the stack (based on frame pointer).
 
   // Provides access to the next frame pointer in a stack frame.
   static FieldAccess ForFrameCallerFramePtr();