[stubs] Port SubStringStub to TurboFan

src/code-stub-assembler.h

 // Copyright 2016 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_CODE_STUB_ASSEMBLER_H_
 #define V8_CODE_STUB_ASSEMBLER_H_
 
 #include <functional>
 
 #include "src/compiler/code-assembler.h"
@@ skipping 93 matching lines @@
   compiler::Node* SmiFromWord32(compiler::Node* value);
   compiler::Node* SmiToWord(compiler::Node* value) { return SmiUntag(value); }
   compiler::Node* SmiToWord32(compiler::Node* value);
 
   // Smi operations.
   compiler::Node* SmiAdd(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiAddWithOverflow(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiSub(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiSubWithOverflow(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiEqual(compiler::Node* a, compiler::Node* b);
+  compiler::Node* SmiAbove(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiAboveOrEqual(compiler::Node* a, compiler::Node* b);
+  compiler::Node* SmiBelow(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiLessThan(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiLessThanOrEqual(compiler::Node* a, compiler::Node* b);
   compiler::Node* SmiMin(compiler::Node* a, compiler::Node* b);
   // Computes a % b for Smi inputs a and b; result is not necessarily a Smi.
   compiler::Node* SmiMod(compiler::Node* a, compiler::Node* b);
   // Computes a * b for Smi inputs a and b; result is not necessarily a Smi.
   compiler::Node* SmiMul(compiler::Node* a, compiler::Node* b);
 
   // Allocate an object of the given size.
   compiler::Node* Allocate(compiler::Node* size, AllocationFlags flags = kNone);
   compiler::Node* Allocate(int size, AllocationFlags flags = kNone);
   compiler::Node* InnerAllocate(compiler::Node* previous, int offset);
   compiler::Node* InnerAllocate(compiler::Node* previous,
                                 compiler::Node* offset);
 
   void Assert(compiler::Node* condition);
 
   // Check a value for smi-ness
   compiler::Node* WordIsSmi(compiler::Node* a);
-  // Check that the value is a positive smi.
+  // Check that the value is a non-negative smi.
   compiler::Node* WordIsPositiveSmi(compiler::Node* a);

[jgruber, 2016/09/21 09:57:11]

Maybe we should change this function name?

+  // Check that the value is a negative smi.
+  compiler::Node* WordIsNegativeSmi(compiler::Node* a);
 
   void BranchIfSmiEqual(compiler::Node* a, compiler::Node* b, Label* if_true,
                         Label* if_false) {
     BranchIf(SmiEqual(a, b), if_true, if_false);
   }
 
   void BranchIfSmiLessThan(compiler::Node* a, compiler::Node* b, Label* if_true,
                            Label* if_false) {
     BranchIf(SmiLessThan(a, b), if_true, if_false);
   }
@@ skipping 169 matching lines @@
   compiler::Node* AllocateHeapNumberWithValue(compiler::Node* value,
                                               MutableMode mode = IMMUTABLE);
   // Allocate a SeqOneByteString with the given length.
   compiler::Node* AllocateSeqOneByteString(int length);
   compiler::Node* AllocateSeqOneByteString(compiler::Node* context,
                                            compiler::Node* length);
   // Allocate a SeqTwoByteString with the given length.
   compiler::Node* AllocateSeqTwoByteString(int length);
   compiler::Node* AllocateSeqTwoByteString(compiler::Node* context,
                                            compiler::Node* length);
+
+  // Allocate a SlicedOneByteString with the given length, parent and offset.
+  compiler::Node* AllocateSlicedOneByteString(compiler::Node* length,
+                                              compiler::Node* parent,
+                                              compiler::Node* offset);
+  // Allocate a SlicedTwoByteString with the given length, parent and offset.
+  compiler::Node* AllocateSlicedTwoByteString(compiler::Node* length,
+                                              compiler::Node* parent,
+                                              compiler::Node* offset);
+
   // Allocate a JSArray without elements and initialize the header fields.
   compiler::Node* AllocateUninitializedJSArrayWithoutElements(
       ElementsKind kind, compiler::Node* array_map, compiler::Node* length,
       compiler::Node* allocation_site);
   // Allocate and return a JSArray with initialized header fields and its
   // uninitialized elements.
   // The ParameterMode argument is only used for the capacity parameter.
   std::pair<compiler::Node*, compiler::Node*>
   AllocateUninitializedJSArrayWithElements(
       ElementsKind kind, compiler::Node* array_map, compiler::Node* length,
@@ skipping 30 matching lines @@
 
   // Copies |element_count| elements from |from_array| to |to_array| of
   // |capacity| size respecting both array's elements kinds.
   void CopyFixedArrayElements(
       ElementsKind from_kind, compiler::Node* from_array, ElementsKind to_kind,
       compiler::Node* to_array, compiler::Node* element_count,
       compiler::Node* capacity,
       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
       ParameterMode mode = INTEGER_PARAMETERS);
 
+  // Copies |character_count| elements from |from_string| to |to_string|
+  // starting at the |from_index|'th character. |from_index| and
+  // |character_count| must be Smis s.t.
+  // 0 <= |from_index| <= |from_index| + |character_count| < from_string.length.
+  void CopyStringCharacters(compiler::Node* from_string,
+                            compiler::Node* to_string,
+                            compiler::Node* from_index,
+                            compiler::Node* character_count,
+                            String::Encoding encoding);
+
   // Loads an element from |array| of |from_kind| elements by given |offset|
   // (NOTE: not index!), does a hole check if |if_hole| is provided and
   // converts the value so that it becomes ready for storing to array of
   // |to_kind| elements.
   compiler::Node* LoadElementAndPrepareForStore(compiler::Node* array,
                                                 compiler::Node* offset,
                                                 ElementsKind from_kind,
                                                 ElementsKind to_kind,
                                                 Label* if_hole);
 
@@ skipping 51 matching lines @@
   compiler::Node* ToThisValue(compiler::Node* context, compiler::Node* value,
                               PrimitiveType primitive_type,
                               char const* method_name);
 
   // String helpers.
   // Load a character from a String (might flatten a ConsString).
   compiler::Node* StringCharCodeAt(compiler::Node* string,
                                    compiler::Node* smi_index);
   // Return the single character string with only {code}.
   compiler::Node* StringFromCharCode(compiler::Node* code);
+  // Return a new string object which holds a substring containing the range
+  // [from,to[ of string.
+  compiler::Node* StringSubString(compiler::Node* context,
+                                  compiler::Node* string, compiler::Node* from,
+                                  compiler::Node* to);
 
   // Type conversion helpers.
   // Convert a String to a Number.
   compiler::Node* StringToNumber(compiler::Node* context,
                                  compiler::Node* input);
   // Convert an object to a name.
   compiler::Node* ToName(compiler::Node* context, compiler::Node* input);
   // Convert a Non-Number object to a Number.
   compiler::Node* NonNumberToNumber(compiler::Node* context,
                                     compiler::Node* input);
@@ skipping 341 matching lines @@
                                            Label* bailout);
 
   static const int kElementLoopUnrollThreshold = 8;
 };
 
 DEFINE_OPERATORS_FOR_FLAGS(CodeStubAssembler::AllocationFlags);
 
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_CODE_STUB_ASSEMBLER_H_