[builtins] Tune Array.indexOf performance

BUG=v8:6371

Change-Id: Iacb4ad572ea83ade6262272ed30d4cb684f9d8ed
Reviewed-on: https://chromium-review.googlesource.com/505107
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45332}

BUILD.gn

@@ -918,6 +918,7 @@ v8_source_set("v8_builtins_generators") {
     "src/builtins/builtins-regexp-gen.h",
     "src/builtins/builtins-sharedarraybuffer-gen.cc",
     "src/builtins/builtins-string-gen.cc",
+    "src/builtins/builtins-string-gen.h",
     "src/builtins/builtins-symbol-gen.cc",
     "src/builtins/builtins-typedarray-gen.cc",
     "src/builtins/builtins-utils-gen.h",

src/builtins/builtins-array-gen.cc

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "src/builtins/builtins-string-gen.h"
 #include "src/builtins/builtins-utils-gen.h"
 #include "src/builtins/builtins.h"
 #include "src/code-stub-assembler.h"
@@ -1703,32 +1704,37 @@ TF_BUILTIN(ArrayIndexOf, CodeStubAssembler) {
   Node* array_length = SmiUntag(LoadJSArrayLength(array));
 
   {
-    // For now only deal with undefined and Smis here; we must be really careful
-    // with side-effects from the ToInteger conversion as the side-effects might
-    // render our assumptions about the receiver being a fast JSArray and the
-    // length invalid.
-    Label done(this);
+    // Initialize fromIndex.
+    Label is_smi(this), is_nonsmi(this), done(this);
 
     // If no fromIndex was passed, default to 0.
     GotoIf(IntPtrLessThanOrEqual(argc, IntPtrConstant(kFromIndexArg)), &done);
 
-    // Handle Smis here and everything else in runtime.
     Node* start_from = args.AtIndex(kFromIndexArg);
-    GotoIfNot(TaggedIsSmi(start_from), &call_runtime);
-
-    Node* intptr_start_from = SmiUntag(start_from);
-    index_var.Bind(intptr_start_from);
-
-    Label if_negative(this);
-    Branch(IntPtrLessThan(intptr_start_from, intptr_zero), &if_negative, &done);
+    // Handle Smis and undefined here and everything else in runtime.
+    // We must be very careful with side effects from the ToInteger conversion,
+    // as the side effects might render previously checked assumptions about
+    // the receiver being a fast JSArray and its length invalid.
+    Branch(TaggedIsSmi(start_from), &is_smi, &is_nonsmi);
 
-    BIND(&if_negative);
+    BIND(&is_nonsmi);
     {
-      Node* len_minus_start_from = IntPtrAdd(array_length, intptr_start_from);
-      index_var.Bind(IntPtrMax(len_minus_start_from, intptr_zero));
+      GotoIfNot(IsUndefined(start_from), &call_runtime);
+      Goto(&done);
+    }
+    BIND(&is_smi);
+    {
+      Node* intptr_start_from = SmiUntag(start_from);
+      index_var.Bind(intptr_start_from);
+
+      GotoIf(IntPtrGreaterThanOrEqual(index_var.value(), intptr_zero), &done);
+      // The fromIndex is negative: add it to the array's length.
+      index_var.Bind(IntPtrAdd(array_length, index_var.value()));
+      // Clamp negative results at zero.
+      GotoIf(IntPtrGreaterThanOrEqual(index_var.value(), intptr_zero), &done);
+      index_var.Bind(intptr_zero);
       Goto(&done);
     }
-
     BIND(&done);
   }
 
@@ -1736,27 +1742,29 @@ TF_BUILTIN(ArrayIndexOf, CodeStubAssembler) {
   GotoIf(IntPtrGreaterThanOrEqual(index_var.value(), array_length),
          &return_not_found);
 
-  static int32_t kElementsKind[] = {
-      FAST_SMI_ELEMENTS,   FAST_HOLEY_SMI_ELEMENTS, FAST_ELEMENTS,
-      FAST_HOLEY_ELEMENTS, FAST_DOUBLE_ELEMENTS,    FAST_HOLEY_DOUBLE_ELEMENTS,
-  };
-
   Label if_smiorobjects(this), if_packed_doubles(this), if_holey_doubles(this);
-  Label* element_kind_handlers[] = {&if_smiorobjects,   &if_smiorobjects,
-                                    &if_smiorobjects,   &if_smiorobjects,
-                                    &if_packed_doubles, &if_holey_doubles};
 
   Node* map = LoadMap(array);
   Node* elements_kind = LoadMapElementsKind(map);
   Node* elements = LoadElements(array);
-  Switch(elements_kind, &return_not_found, kElementsKind, element_kind_handlers,
-         arraysize(kElementsKind));
+  STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
+  STATIC_ASSERT(FAST_ELEMENTS == 2);
+  STATIC_ASSERT(FAST_HOLEY_ELEMENTS == 3);
+  GotoIf(
+      Uint32LessThanOrEqual(elements_kind, Int32Constant(FAST_HOLEY_ELEMENTS)),
+      &if_smiorobjects);
+  GotoIf(Word32Equal(elements_kind, Int32Constant(FAST_DOUBLE_ELEMENTS)),
+         &if_packed_doubles);
+  GotoIf(Word32Equal(elements_kind, Int32Constant(FAST_HOLEY_DOUBLE_ELEMENTS)),
+         &if_holey_doubles);
+  Goto(&return_not_found);
 
   BIND(&if_smiorobjects);
   {
     VARIABLE(search_num, MachineRepresentation::kFloat64);
     Label ident_loop(this, &index_var), heap_num_loop(this, &search_num),
-        string_loop(this, &index_var), not_smi(this), not_heap_num(this);
+        string_loop(this), not_smi(this), not_heap_num(this);
 
     GotoIfNot(TaggedIsSmi(search_element), &not_smi);
     search_num.Bind(SmiToFloat64(search_element));
@@ -1814,22 +1822,35 @@ TF_BUILTIN(ArrayIndexOf, CodeStubAssembler) {
     BIND(&string_loop);
     {
       CSA_ASSERT(this, IsString(search_element));
-      Label continue_loop(this);
+      Label continue_loop(this), next_iteration(this, &index_var),
+          slow_compare(this), runtime(this, Label::kDeferred);
+      Node* search_length = LoadStringLength(search_element);
+      Goto(&next_iteration);
+      BIND(&next_iteration);
       GotoIfNot(UintPtrLessThan(index_var.value(), array_length),
                 &return_not_found);
       Node* element_k = LoadFixedArrayElement(elements, index_var.value());
       GotoIf(TaggedIsSmi(element_k), &continue_loop);
-      GotoIfNot(IsString(element_k), &continue_loop);
-
-      // TODO(bmeurer): Consider inlining the StringEqual logic here.
-      Callable callable = CodeFactory::StringEqual(isolate());
-      Node* result = CallStub(callable, context, search_element, element_k);
+      GotoIf(WordEqual(search_element, element_k), &return_found);
+      Node* element_k_type = LoadInstanceType(element_k);
+      GotoIfNot(IsStringInstanceType(element_k_type), &continue_loop);
+      Branch(WordEqual(search_length, LoadStringLength(element_k)),
+             &slow_compare, &continue_loop);
+
+      BIND(&slow_compare);
+      StringBuiltinsAssembler string_asm(state());
+      string_asm.StringEqual_Core(context, search_element, search_type,
+                                  search_length, element_k, element_k_type,
+                                  &return_found, &continue_loop, &runtime);
+      BIND(&runtime);
+      Node* result = CallRuntime(Runtime::kStringEqual, context, search_element,
+                                 element_k);
       Branch(WordEqual(BooleanConstant(true), result), &return_found,
              &continue_loop);
 
       BIND(&continue_loop);
       Increment(index_var);
-      Goto(&string_loop);
+      Goto(&next_iteration);
     }
   }
 

src/builtins/builtins-string-gen.h

+// Copyright 2017 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.
+
+#ifndef V8_BUILTINS_BUILTINS_STRING_GEN_H_
+#define V8_BUILTINS_BUILTINS_STRING_GEN_H_
+
+#include "src/code-stub-assembler.h"
+
+namespace v8 {
+namespace internal {
+
+class StringBuiltinsAssembler : public CodeStubAssembler {
+ public:
+  explicit StringBuiltinsAssembler(compiler::CodeAssemblerState* state)
+      : CodeStubAssembler(state) {}
+
+  // ES#sec-getsubstitution
+  Node* GetSubstitution(Node* context, Node* subject_string,
+                        Node* match_start_index, Node* match_end_index,
+                        Node* replace_string);
+  void StringEqual_Core(Node* context, Node* lhs, Node* lhs_instance_type,
+                        Node* lhs_length, Node* rhs, Node* rhs_instance_type,
+                        Label* if_equal, Label* if_not_equal,
+                        Label* if_notbothdirectonebyte);
+
+ protected:
+  Node* DirectStringData(Node* string, Node* string_instance_type);
+
+  void DispatchOnStringEncodings(Node* const lhs_instance_type,
+                                 Node* const rhs_instance_type,
+                                 Label* if_one_one, Label* if_one_two,
+                                 Label* if_two_one, Label* if_two_two);
+
+  template <typename SubjectChar, typename PatternChar>
+  Node* CallSearchStringRaw(Node* const subject_ptr, Node* const subject_length,
+                            Node* const search_ptr, Node* const search_length,
+                            Node* const start_position);
+
+  Node* PointerToStringDataAtIndex(Node* const string_data, Node* const index,
+                                   String::Encoding encoding);
+
+  // substr and slice have a common way of handling the {start} argument.
+  void ConvertAndBoundsCheckStartArgument(Node* context, Variable* var_start,
+                                          Node* start, Node* string_length);
+
+  void GenerateStringEqual(Node* context, Node* left, Node* right);
+  void GenerateStringRelationalComparison(Node* context, Node* left,
+                                          Node* right,
+                                          RelationalComparisonMode mode);
+
+  Node* ToSmiBetweenZeroAnd(Node* context, Node* value, Node* limit);
+
+  Node* LoadSurrogatePairAt(Node* string, Node* length, Node* index,
+                            UnicodeEncoding encoding);
+
+  void StringIndexOf(Node* const subject_string,
+                     Node* const subject_instance_type,
+                     Node* const search_string,
+                     Node* const search_instance_type, Node* const position,
+                     std::function<void(Node*)> f_return);
+
+  Node* IndexOfDollarChar(Node* const context, Node* const string);
+
+  Node* IsNullOrUndefined(Node* const value);
+  void RequireObjectCoercible(Node* const context, Node* const value,
+                              const char* method_name);
+
+  Node* SmiIsNegative(Node* const value) {
+    return SmiLessThan(value, SmiConstant(0));
+  }
+
+  // Implements boilerplate logic for {match, split, replace, search} of the
+  // form:
+  //
+  //  if (!IS_NULL_OR_UNDEFINED(object)) {
+  //    var maybe_function = object[symbol];
+  //    if (!IS_UNDEFINED(maybe_function)) {
+  //      return %_Call(maybe_function, ...);
+  //    }
+  //  }
+  //
+  // Contains fast paths for Smi and RegExp objects.
+  typedef std::function<Node*()> NodeFunction0;
+  typedef std::function<Node*(Node* fn)> NodeFunction1;
+  void MaybeCallFunctionAtSymbol(Node* const context, Node* const object,
+                                 Handle<Symbol> symbol,
+                                 const NodeFunction0& regexp_call,
+                                 const NodeFunction1& generic_call);
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_BUILTINS_BUILTINS_STRING_GEN_H_

src/debug/debug-evaluate.cc

@@ -319,6 +319,7 @@ bool IntrinsicHasNoSideEffect(Runtime::FunctionId id) {
   V(StringParseInt)                  \
   V(StringCharCodeAtRT)              \
   V(StringIndexOfUnchecked)          \
+  V(StringEqual)                     \
   V(SymbolDescriptiveString)         \
   V(GenerateRandomNumbers)           \
   V(ExternalStringGetChar)           \
@@ -679,6 +680,7 @@ bool DebugEvaluate::FunctionHasNoSideEffect(Handle<SharedFunctionInfo> info) {
     if (builtin_index >= 0 && builtin_index < Builtins::builtin_count &&
         BuiltinHasNoSideEffect(static_cast<Builtins::Name>(builtin_index))) {
 #ifdef DEBUG
+      // TODO(yangguo): Check builtin-to-builtin calls too.
       int mode = RelocInfo::ModeMask(RelocInfo::EXTERNAL_REFERENCE);
       bool failed = false;
       for (RelocIterator it(info->code(), mode); !it.done(); it.next()) {

src/v8.gyp

@@ -527,6 +527,7 @@
         'builtins/builtins-sharedarraybuffer-gen.cc',
         'builtins/builtins-string.cc',
         'builtins/builtins-string-gen.cc',
+        'builtins/builtins-string-gen.h',
         'builtins/builtins-intl.cc',
         'builtins/builtins-intl-gen.cc',
         'builtins/builtins-symbol.cc',