[turbofan] Remove dead code (related to the SeqStringChar lowering removal).

Review URL: https://codereview.chromium.org/1453103002

Cr-Commit-Position: refs/heads/master@{#32034}

src/compiler/access-builder.cc

@@ -304,26 +304,6 @@ ElementAccess AccessBuilder::ForTypedArrayElement(ExternalArrayType type,
 }
 
 
-// static
-ElementAccess AccessBuilder::ForSeqStringChar(String::Encoding encoding) {
-  switch (encoding) {
-    case String::ONE_BYTE_ENCODING: {
-      ElementAccess access = {kTaggedBase, SeqString::kHeaderSize,
-                              Type::Unsigned32(), kMachUint8};
-      return access;
-    }
-    case String::TWO_BYTE_ENCODING: {
-      ElementAccess access = {kTaggedBase, SeqString::kHeaderSize,
-                              Type::Unsigned32(), kMachUint16};
-      return access;
-    }
-  }
-  UNREACHABLE();
-  ElementAccess access = {kUntaggedBase, 0, Type::None(), kMachNone};
-  return access;
-}
-
-
 // static
 FieldAccess AccessBuilder::ForStatsCounter() {
   FieldAccess access = {kUntaggedBase, 0, MaybeHandle<Name>(),

src/compiler/access-builder.h

@@ -103,9 +103,6 @@ class AccessBuilder final : public AllStatic {
   static ElementAccess ForTypedArrayElement(ExternalArrayType type,
                                             bool is_external);
 
-  // Provides access to the characters of sequential strings.
-  static ElementAccess ForSeqStringChar(String::Encoding encoding);
-
   // ===========================================================================
   // Access to global per-isolate variables (based on external reference).
 

src/compiler/js-intrinsic-lowering.h

@@ -53,8 +53,6 @@ class JSIntrinsicLowering final : public AdvancedReducer {
   Reduction ReduceMathClz32(Node* node);
   Reduction ReduceMathFloor(Node* node);
   Reduction ReduceMathSqrt(Node* node);
-  Reduction ReduceSeqStringGetChar(Node* node, String::Encoding encoding);
-  Reduction ReduceSeqStringSetChar(Node* node, String::Encoding encoding);
   Reduction ReduceStringGetLength(Node* node);
   Reduction ReduceValueOf(Node* node);
   Reduction ReduceFixedArrayGet(Node* node);