Remove SubString intrinsic and convert SubString code stub to CSA.

Bug: v8:5049
Change-Id: Ia4f5729be64794e9080eb0e644b86cd5d8c88a11
Reviewed-on: https://chromium-review.googlesource.com/722168Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48661}

src/builtins/builtins-definitions.h

@@ -100,6 +100,7 @@ namespace internal {
   TFC(StringLessThan, Compare, 1)                                              \
   TFC(StringLessThanOrEqual, Compare, 1)                                       \
   TFS(StringRepeat, kString, kCount)                                           \
+  TFS(SubString, kString, kFrom, kTo)                                          \
                                                                                \
   /* OrderedHashTable helpers */                                               \
   TFS(OrderedHashTableHealIndex, kTable, kIndex)                               \

src/builtins/builtins-string-gen.cc

@@ -1166,9 +1166,9 @@ compiler::Node* StringBuiltinsAssembler::GetSubstitution(
   {
     CSA_ASSERT(this, TaggedIsPositiveSmi(dollar_index));
 
-    Callable substring_callable = CodeFactory::SubString(isolate());
-    Node* const matched = CallStub(substring_callable, context, subject_string,
-                                   match_start_index, match_end_index);
+    Node* const matched =
+        CallBuiltin(Builtins::kSubString, context, subject_string,
+                    match_start_index, match_end_index);
     Node* const replacement_string =
         CallRuntime(Runtime::kGetSubstitution, context, matched, subject_string,
                     match_start_index, replace_string, dollar_index);
@@ -1396,7 +1396,6 @@ TF_BUILTIN(StringPrototypeReplace, StringBuiltinsAssembler) {
 
   Node* const match_end_index = SmiAdd(match_start_index, search_length);
 
-  Callable substring_callable = CodeFactory::SubString(isolate());
   Callable stringadd_callable =
       CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, NOT_TENURED);
 
@@ -1407,8 +1406,9 @@ TF_BUILTIN(StringPrototypeReplace, StringBuiltinsAssembler) {
     Label next(this);
 
     GotoIf(SmiEqual(match_start_index, smi_zero), &next);
-    Node* const prefix = CallStub(substring_callable, context, subject_string,
-                                  smi_zero, match_start_index);
+    Node* const prefix =
+        CallBuiltin(Builtins::kSubString, context, subject_string, smi_zero,
+                    match_start_index);
     var_result.Bind(prefix);
 
     Goto(&next);
@@ -1447,8 +1447,9 @@ TF_BUILTIN(StringPrototypeReplace, StringBuiltinsAssembler) {
 
   BIND(&out);
   {
-    Node* const suffix = CallStub(substring_callable, context, subject_string,
-                                  match_end_index, subject_length);
+    Node* const suffix =
+        CallBuiltin(Builtins::kSubString, context, subject_string,
+                    match_end_index, subject_length);
     Node* const result =
         CallStub(stringadd_callable, context, var_result.value(), suffix);
     Return(result);
@@ -1628,10 +1629,9 @@ class StringPadAssembler : public StringBuiltinsAssembler {
 
         GotoIfNot(remaining_word32, &return_result);
         {
-          Callable substring_callable = CodeFactory::SubString(isolate());
-          Node* const remainder_string =
-              CallStub(substring_callable, context, var_fill_string.value(),
-                       SmiConstant(0), SmiFromWord32(remaining_word32));
+          Node* const remainder_string = CallBuiltin(
+              Builtins::kSubString, context, var_fill_string.value(),
+              SmiConstant(0), SmiFromWord32(remaining_word32));
           var_pad.Bind(CallStub(stringadd_callable, context, var_pad.value(),
                                 remainder_string));
           Goto(&return_result);
@@ -1998,6 +1998,15 @@ TNode<Smi> StringBuiltinsAssembler::ToSmiBetweenZeroAnd(
   return var_result;
 }
 
+TF_BUILTIN(SubString, CodeStubAssembler) {
+  Node* context = Parameter(Descriptor::kContext);
+  Node* string = Parameter(Descriptor::kString);
+  Node* from = Parameter(Descriptor::kFrom);
+  Node* to = Parameter(Descriptor::kTo);
+
+  Return(SubString(context, string, from, to));
+}
+
 // ES6 #sec-string.prototype.substring
 TF_BUILTIN(StringPrototypeSubstring, StringBuiltinsAssembler) {
   const int kStartArg = 0;

src/code-factory.cc

@@ -178,12 +178,6 @@ Callable CodeFactory::StringCompare(Isolate* isolate, Token::Value token) {
   UNREACHABLE();
 }
 
-// static
-Callable CodeFactory::SubString(Isolate* isolate) {
-  SubStringStub stub(isolate);
-  return Callable(stub.GetCode(), stub.GetCallInterfaceDescriptor());
-}
-
 // static
 Callable CodeFactory::ResumeGenerator(Isolate* isolate) {
   return Callable(BUILTIN_CODE(isolate, ResumeGeneratorTrampoline),

src/code-factory.h

@@ -58,7 +58,6 @@ class V8_EXPORT_PRIVATE CodeFactory final {
                             StringAddFlags flags = STRING_ADD_CHECK_NONE,
                             PretenureFlag pretenure_flag = NOT_TENURED);
   static Callable StringCompare(Isolate* isolate, Token::Value token);
-  static Callable SubString(Isolate* isolate);
 
   static Callable FastNewFunctionContext(Isolate* isolate,
                                          ScopeType scope_type);

src/code-stubs.cc

@@ -362,16 +362,6 @@ TF_STUB(NumberToStringStub, CodeStubAssembler) {
   Return(NumberToString(context, argument));
 }
 
-// TODO(ishell): move to builtins.
-TF_STUB(SubStringStub, CodeStubAssembler) {
-  Node* context = Parameter(Descriptor::kContext);
-  Node* string = Parameter(Descriptor::kString);
-  Node* from = Parameter(Descriptor::kFrom);
-  Node* to = Parameter(Descriptor::kTo);
-
-  Return(SubString(context, string, from, to));
-}
-
 // TODO(ishell): move to builtins-handler-gen.
 TF_STUB(KeyedLoadSloppyArgumentsStub, CodeStubAssembler) {
   Node* receiver = Parameter(Descriptor::kReceiver);

src/code-stubs.h

@@ -41,7 +41,6 @@ class Node;
   V(RecordWrite)                              \
   V(StoreBufferOverflow)                      \
   V(StoreSlowElement)                         \
-  V(SubString)                                \
   V(NameDictionaryLookup)                     \
   /* --- TurboFanCodeStubs --- */             \
   V(ArrayNoArgumentConstructor)               \
@@ -1114,15 +1113,6 @@ class StoreBufferOverflowStub : public PlatformCodeStub {
   DEFINE_PLATFORM_CODE_STUB(StoreBufferOverflow, PlatformCodeStub);
 };
 
-class SubStringStub : public TurboFanCodeStub {
- public:
-  explicit SubStringStub(Isolate* isolate) : TurboFanCodeStub(isolate) {}
-
-  DEFINE_CALL_INTERFACE_DESCRIPTOR(SubString);
-  DEFINE_TURBOFAN_CODE_STUB(SubString, TurboFanCodeStub);
-};
-
-
 #undef DEFINE_CALL_INTERFACE_DESCRIPTOR
 #undef DEFINE_PLATFORM_CODE_STUB
 #undef DEFINE_HANDLER_CODE_STUB

src/compiler/js-intrinsic-lowering.cc

@@ -69,8 +69,6 @@ Reduction JSIntrinsicLowering::Reduce(Node* node) {
       return ReduceIsJSReceiver(node);
     case Runtime::kInlineIsSmi:
       return ReduceIsSmi(node);
-    case Runtime::kInlineSubString:
-      return ReduceSubString(node);
     case Runtime::kInlineToInteger:
       return ReduceToInteger(node);
     case Runtime::kInlineToLength:
@@ -281,11 +279,6 @@ Reduction JSIntrinsicLowering::Change(Node* node, const Operator* op) {
   return Changed(node);
 }
 
-Reduction JSIntrinsicLowering::ReduceSubString(Node* node) {
-  return Change(node, CodeFactory::SubString(isolate()), 3);
-}
-
-
 Reduction JSIntrinsicLowering::ReduceToInteger(Node* node) {
   NodeProperties::ChangeOp(node, javascript()->ToInteger());
   return Changed(node);

src/compiler/js-intrinsic-lowering.h

@@ -54,7 +54,6 @@ class V8_EXPORT_PRIVATE JSIntrinsicLowering final
   Reduction ReduceIsInstanceType(Node* node, InstanceType instance_type);
   Reduction ReduceIsJSReceiver(Node* node);
   Reduction ReduceIsSmi(Node* node);
-  Reduction ReduceSubString(Node* node);
   Reduction ReduceToInteger(Node* node);
   Reduction ReduceToLength(Node* node);
   Reduction ReduceToNumber(Node* node);

src/compiler/typer.cc

@@ -1678,7 +1678,6 @@ Type* Typer::Visitor::TypeJSCallRuntime(Node* node) {
       return Type::Boolean();
     case Runtime::kInlineCreateIterResultObject:
       return Type::OtherObject();
-    case Runtime::kInlineSubString:
     case Runtime::kInlineStringCharFromCode:
       return Type::String();
     case Runtime::kInlineToInteger:

src/debug/debug-evaluate.cc

@@ -630,6 +630,7 @@ bool BuiltinHasNoSideEffect(Builtins::Name id) {
     case Builtins::kStringPrototypeTrimRight:
     case Builtins::kStringPrototypeValueOf:
     case Builtins::kStringToNumber:
+    case Builtins::kSubString:
     // Symbol builtins.
     case Builtins::kSymbolConstructor:
     case Builtins::kSymbolKeyFor:

src/interface-descriptors.h

@@ -63,7 +63,6 @@ class PlatformInterfaceDescriptor;
   V(StringCharAt)                     \
   V(StringCharCodeAt)                 \
   V(StringCompare)                    \
-  V(SubString)                        \
   V(ForInPrepare)                     \
   V(GetProperty)                      \
   V(ArgumentAdaptor)                  \
@@ -750,13 +749,6 @@ class StringCompareDescriptor : public CallInterfaceDescriptor {
   static const Register RightRegister();
 };
 
-class SubStringDescriptor : public CallInterfaceDescriptor {
- public:
-  DEFINE_PARAMETERS(kString, kFrom, kTo)
-  DECLARE_DESCRIPTOR_WITH_STACK_ARGS(SubStringDescriptor,
-                                     CallInterfaceDescriptor)
-};
-
 class ArgumentAdaptorDescriptor : public CallInterfaceDescriptor {
  public:
   DEFINE_PARAMETERS(kFunction, kNewTarget, kActualArgumentsCount,

src/interpreter/interpreter-intrinsics-generator.cc

@@ -282,11 +282,6 @@ Node* IntrinsicsGenerator::HasProperty(Node* input, Node* arg_count,
       input, context, Builtins::CallableFor(isolate(), Builtins::kHasProperty));
 }
 
-Node* IntrinsicsGenerator::SubString(Node* input, Node* arg_count,
-                                     Node* context) {
-  return IntrinsicAsStubCall(input, context, CodeFactory::SubString(isolate()));
-}
-
 Node* IntrinsicsGenerator::ToString(Node* input, Node* arg_count,
                                     Node* context) {
   return IntrinsicAsStubCall(

src/interpreter/interpreter-intrinsics.h

@@ -36,7 +36,6 @@ namespace interpreter {
   V(IsJSWeakSet, is_js_weak_set, 1)                                   \
   V(IsSmi, is_smi, 1)                                                 \
   V(IsTypedArray, is_typed_array, 1)                                  \
-  V(SubString, sub_string, 3)                                         \
   V(ToString, to_string, 1)                                           \
   V(ToLength, to_length, 1)                                           \
   V(ToInteger, to_integer, 1)                                         \

src/runtime/runtime-strings.cc

@@ -237,8 +237,9 @@ RUNTIME_FUNCTION(Runtime_SubString) {
   } else {
     return isolate->ThrowIllegalOperation();
   }
-  // The following condition is intentionally robust because the SubStringStub
-  // delegates here and we test this in cctest/test-strings/RobustSubStringStub.
+  // The following condition is intentionally robust because the SubString
+  // builtin delegates here and we test this in
+  // cctest/test-strings/RobustSubStringStub.
   if (end < start || start < 0 || end > string->length()) {
     return isolate->ThrowIllegalOperation();
   }

test/cctest/compiler/test-run-intrinsics.cc

@@ -116,14 +116,6 @@ TEST(StringCompare) {
 }
 
 
-TEST(SubString) {
-  FunctionTester T("(function(a,b) { return %_SubString(a,b,b+3); })", flags);
-
-  T.CheckCall(T.Val("aaa"), T.Val("aaabbb"), T.Val(0.0));
-  T.CheckCall(T.Val("abb"), T.Val("aaabbb"), T.Val(2));
-  T.CheckCall(T.Val("aaa"), T.Val("aaa"), T.Val(0.0));
-}
-
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8

test/cctest/interpreter/test-interpreter-intrinsics.cc

@@ -216,14 +216,6 @@ TEST(IntrinsicAsStubCall) {
            *has_property_helper.Invoke(
                has_property_helper.NewObject("'y'"),
                has_property_helper.NewObject("({ x: 20 })")));
-
-  InvokeIntrinsicHelper sub_string_helper(isolate, handles.main_zone(),
-                                          Runtime::kInlineSubString);
-  CHECK(sub_string_helper
-            .Invoke(sub_string_helper.NewObject("'foobar'"),
-                    sub_string_helper.NewObject("3"),
-                    sub_string_helper.NewObject("6"))
-            ->SameValue(*sub_string_helper.NewObject("'bar'")));
 }
 
 TEST(ClassOf) {