[stubs] Add RegExpReplace and RegExpSplit stubs

src/builtins/builtins-regexp.cc

Index: src/builtins/builtins-regexp.cc
diff --git a/src/builtins/builtins-regexp.cc b/src/builtins/builtins-regexp.cc
index b907a1bf45dd0559bbf92279e69cb6704121e94f..95979c91e1908023617c155bc685afa9e0b5934f 100644
--- a/src/builtins/builtins-regexp.cc
+++ b/src/builtins/builtins-regexp.cc
@@ -422,9 +422,10 @@ Node* RegExpBuiltinsAssembler::IsInitialRegExpMap(Node* context, Node* map) {
 // We use a fairly coarse granularity for this and simply check whether both
 // the regexp itself is unmodified (i.e. its map has not changed) and its
 // prototype is unmodified.
-void RegExpBuiltinsAssembler::BranchIfFastRegExp(Node* context, Node* map,
-                                                 Label* if_isunmodified,
-                                                 Label* if_ismodified) {
+void RegExpBuiltinsAssembler::BranchIfFastRegExp(Node* const context,
+                                                 Node* const map,
+                                                 Label* const if_isunmodified,
+                                                 Label* const if_ismodified) {
   Node* const native_context = LoadNativeContext(context);
   Node* const regexp_fun =
       LoadContextElement(native_context, Context::REGEXP_FUNCTION_INDEX);
@@ -446,6 +447,25 @@ void RegExpBuiltinsAssembler::BranchIfFastRegExp(Node* context, Node* map,
   Branch(proto_has_initialmap, if_isunmodified, if_ismodified);
 }
 
+Node* RegExpBuiltinsAssembler::IsFastRegExpMap(Node* const context,
+                                               Node* const map) {
+  Label yup(this), nope(this), out(this);
+  Variable var_result(this, MachineRepresentation::kWord32);
+
+  BranchIfFastRegExp(context, map, &yup, &nope);
+
+  Bind(&yup);
+  var_result.Bind(Int32Constant(1));
+  Goto(&out);
+
+  Bind(&nope);
+  var_result.Bind(Int32Constant(0));
+  Goto(&out);
+
+  Bind(&out);
+  return var_result.value();
+}
+
 void RegExpBuiltinsAssembler::BranchIfFastRegExpResult(Node* context, Node* map,
                                                        Label* if_isunmodified,
                                                        Label* if_ismodified) {
@@ -2029,6 +2049,51 @@ void RegExpBuiltinsAssembler::RegExpPrototypeSplitBody(Node* const context,
   }
 }
 
+// Helper that skips a few initial checks.
+TF_BUILTIN(RegExpSplit, RegExpBuiltinsAssembler) {
+  typedef RegExpSplitDescriptor Descriptor;
+
+  Node* const regexp = Parameter(Descriptor::kReceiver);
+  Node* const string = Parameter(Descriptor::kString);
+  Node* const maybe_limit = Parameter(Descriptor::kLimit);
+  Node* const context = Parameter(Descriptor::kContext);
+
+  CSA_ASSERT(this, IsFastRegExpMap(context, LoadMap(regexp)));
+  CSA_ASSERT(this, IsString(string));
+
+  // TODO(jgruber): Even if map checks send us to the fast path, we still need
+  // to verify the constructor property and jump to the slow path if it has
+  // been changed.
+
+  // Convert {maybe_limit} to a uint32, capping at the maximal smi value.
+  Variable var_limit(this, MachineRepresentation::kTagged);
+  Label if_limitissmimax(this), limit_done(this);
+
+  GotoIf(IsUndefined(maybe_limit), &if_limitissmimax);
+
+  {
+    Node* const limit = ToUint32(context, maybe_limit);
+    GotoUnless(TaggedIsSmi(limit), &if_limitissmimax);
+
+    var_limit.Bind(limit);
+    Goto(&limit_done);
+  }
+
+  Bind(&if_limitissmimax);
+  {
+    // TODO(jgruber): In this case, we can probably avoid generation of limit
+    // checks in Generate_RegExpPrototypeSplitBody.
+    var_limit.Bind(SmiConstant(Smi::kMaxValue));
+    Goto(&limit_done);
+  }
+
+  Bind(&limit_done);
+  {
+    Node* const limit = var_limit.value();
+    RegExpPrototypeSplitBody(context, regexp, string, limit);
+  }
+}
+
 // ES#sec-regexp.prototype-@@split
 // RegExp.prototype [ @@split ] ( string, limit )
 TF_BUILTIN(RegExpPrototypeSplit, RegExpBuiltinsAssembler) {
@@ -2046,51 +2111,16 @@ TF_BUILTIN(RegExpPrototypeSplit, RegExpBuiltinsAssembler) {
   // Convert {maybe_string} to a String.
   Node* const string = ToString(context, maybe_string);
 
-  Label fast_path(this), slow_path(this);
-  BranchIfFastRegExp(context, map, &fast_path, &slow_path);
-
-  Bind(&fast_path);
-  {
-    // TODO(jgruber): Even if map checks send us to the fast path, we still need
-    // to verify the constructor property and jump to the slow path if it has
-    // been changed.
-
-    // Convert {maybe_limit} to a uint32, capping at the maximal smi value.
-    Variable var_limit(this, MachineRepresentation::kTagged);
-    Label if_limitissmimax(this), limit_done(this);
-
-    GotoIf(IsUndefined(maybe_limit), &if_limitissmimax);
-
-    {
-      Node* const limit = ToUint32(context, maybe_limit);
-      GotoUnless(TaggedIsSmi(limit), &if_limitissmimax);
-
-      var_limit.Bind(limit);
-      Goto(&limit_done);
-    }
-
-    Bind(&if_limitissmimax);
-    {
-      // TODO(jgruber): In this case, we can probably generation of limit checks
-      // in Generate_RegExpPrototypeSplitBody.
-      Node* const smi_max = SmiConstant(Smi::kMaxValue);
-      var_limit.Bind(smi_max);
-      Goto(&limit_done);
-    }
+  Label stub(this), runtime(this, Label::kDeferred);
+  BranchIfFastRegExp(context, map, &stub, &runtime);
 
-    Bind(&limit_done);
-    {
-      Node* const limit = var_limit.value();
-      RegExpPrototypeSplitBody(context, receiver, string, limit);
-    }
-  }
+  Bind(&stub);
+  Callable split_callable = CodeFactory::RegExpSplit(isolate());
+  Return(CallStub(split_callable, context, receiver, string, maybe_limit));
 
-  Bind(&slow_path);
-  {
-    Node* const result = CallRuntime(Runtime::kRegExpSplit, context, receiver,
-                                     string, maybe_limit);
-    Return(result);
-  }
+  Bind(&runtime);
+  Return(CallRuntime(Runtime::kRegExpSplit, context, receiver, string,
+                     maybe_limit));
 }
 
 Node* RegExpBuiltinsAssembler::ReplaceGlobalCallableFastPath(
@@ -2406,50 +2436,37 @@ Node* RegExpBuiltinsAssembler::ReplaceSimpleStringFastPath(
   return var_result.value();
 }
 
-// ES#sec-regexp.prototype-@@replace
-// RegExp.prototype [ @@replace ] ( string, replaceValue )
-TF_BUILTIN(RegExpPrototypeReplace, RegExpBuiltinsAssembler) {
-  Node* const maybe_receiver = Parameter(0);
-  Node* const maybe_string = Parameter(1);
-  Node* const replace_value = Parameter(2);
-  Node* const context = Parameter(5);
-
-  // Ensure {maybe_receiver} is a JSReceiver.
-  Node* const map = ThrowIfNotJSReceiver(
-      context, maybe_receiver, MessageTemplate::kIncompatibleMethodReceiver,
-      "RegExp.prototype.@@replace");
-  Node* const receiver = maybe_receiver;
+// Helper that skips a few initial checks.
+TF_BUILTIN(RegExpReplace, RegExpBuiltinsAssembler) {
+  typedef RegExpReplaceDescriptor Descriptor;
 
-  // Convert {maybe_string} to a String.
-  Callable tostring_callable = CodeFactory::ToString(isolate());
-  Node* const string = CallStub(tostring_callable, context, maybe_string);
+  Node* const regexp = Parameter(Descriptor::kReceiver);
+  Node* const string = Parameter(Descriptor::kString);
+  Node* const replace_value = Parameter(Descriptor::kReplaceValue);
+  Node* const context = Parameter(Descriptor::kContext);
 
-  // Fast-path checks: 1. Is the {receiver} an unmodified JSRegExp instance?
-  Label checkreplacecallable(this), runtime(this, Label::kDeferred),
-      fastpath(this);
-  BranchIfFastRegExp(context, map, &checkreplacecallable, &runtime);
+  CSA_ASSERT(this, IsFastRegExpMap(context, LoadMap(regexp)));
+  CSA_ASSERT(this, IsString(string));
 
-  Bind(&checkreplacecallable);
-  Node* const regexp = receiver;
+  Label checkreplacestring(this), if_iscallable(this),
+      runtime(this, Label::kDeferred);
 
   // 2. Is {replace_value} callable?
-  Label checkreplacestring(this), if_iscallable(this);
   GotoIf(TaggedIsSmi(replace_value), &checkreplacestring);
-
-  Node* const replace_value_map = LoadMap(replace_value);
-  Branch(IsCallableMap(replace_value_map), &if_iscallable, &checkreplacestring);
+  Branch(IsCallableMap(LoadMap(replace_value)), &if_iscallable,
+         &checkreplacestring);
 
   // 3. Does ToString({replace_value}) contain '$'?
   Bind(&checkreplacestring);
   {
+    Callable tostring_callable = CodeFactory::ToString(isolate());
     Node* const replace_string =
         CallStub(tostring_callable, context, replace_value);
 
     Node* const dollar_char = Int32Constant('$');
-    Node* const smi_minusone = SmiConstant(Smi::FromInt(-1));
     GotoUnless(SmiEqual(StringIndexOfChar(context, replace_string, dollar_char,
                                           SmiConstant(0)),
-                        smi_minusone),
+                        SmiConstant(-1)),
                &runtime);
 
     Return(
@@ -2459,35 +2476,56 @@ TF_BUILTIN(RegExpPrototypeReplace, RegExpBuiltinsAssembler) {
   // {regexp} is unmodified and {replace_value} is callable.
   Bind(&if_iscallable);
   {
-    Node* const replace_callable = replace_value;
+    Node* const replace_fn = replace_value;
 
     // Check if the {regexp} is global.
     Label if_isglobal(this), if_isnotglobal(this);
+
     Node* const is_global = FastFlagGetter(regexp, JSRegExp::kGlobal);
     Branch(is_global, &if_isglobal, &if_isnotglobal);
 
     Bind(&if_isglobal);
-    {
-      Node* const result = ReplaceGlobalCallableFastPath(
-          context, regexp, string, replace_callable);
-      Return(result);
-    }
+    Return(ReplaceGlobalCallableFastPath(context, regexp, string, replace_fn));
 
     Bind(&if_isnotglobal);
-    {
-      Node* const result =
-          CallRuntime(Runtime::kStringReplaceNonGlobalRegExpWithFunction,
-                      context, string, regexp, replace_callable);
-      Return(result);
-    }
+    Return(CallRuntime(Runtime::kStringReplaceNonGlobalRegExpWithFunction,
+                       context, string, regexp, replace_fn));
   }
 
   Bind(&runtime);
-  {
-    Node* const result = CallRuntime(Runtime::kRegExpReplace, context, receiver,
-                                     string, replace_value);
-    Return(result);
-  }
+  Return(CallRuntime(Runtime::kRegExpReplace, context, regexp, string,
+                     replace_value));
+}
+
+// ES#sec-regexp.prototype-@@replace
+// RegExp.prototype [ @@replace ] ( string, replaceValue )
+TF_BUILTIN(RegExpPrototypeReplace, RegExpBuiltinsAssembler) {
+  Node* const maybe_receiver = Parameter(0);
+  Node* const maybe_string = Parameter(1);
+  Node* const replace_value = Parameter(2);
+  Node* const context = Parameter(5);
+
+  // Ensure {maybe_receiver} is a JSReceiver.
+  Node* const map = ThrowIfNotJSReceiver(
+      context, maybe_receiver, MessageTemplate::kIncompatibleMethodReceiver,
+      "RegExp.prototype.@@replace");
+  Node* const receiver = maybe_receiver;
+
+  // Convert {maybe_string} to a String.
+  Callable tostring_callable = CodeFactory::ToString(isolate());
+  Node* const string = CallStub(tostring_callable, context, maybe_string);
+
+  // Fast-path checks: 1. Is the {receiver} an unmodified JSRegExp instance?
+  Label stub(this), runtime(this, Label::kDeferred);
+  BranchIfFastRegExp(context, map, &stub, &runtime);
+
+  Bind(&stub);
+  Callable replace_callable = CodeFactory::RegExpReplace(isolate());
+  Return(CallStub(replace_callable, context, receiver, string, replace_value));
+
+  Bind(&runtime);
+  Return(CallRuntime(Runtime::kRegExpReplace, context, receiver, string,
+                     replace_value));
 }
 
 // Simple string matching functionality for internal use which does not modify