[csa] Re-introduce automatic constant folding for IntPtrAdd and IntPtrSub

src/compiler/code-assembler.h

 // Copyright 2015 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_COMPILER_CODE_ASSEMBLER_H_
 #define V8_COMPILER_CODE_ASSEMBLER_H_
 
 #include <map>
 #include <memory>
 
@@ skipping 67 matching lines @@
   CODE_ASSEMBLER_COMPARE_BINARY_OP_LIST(V) \
   V(Float64Add)                            \
   V(Float64Sub)                            \
   V(Float64Mul)                            \
   V(Float64Div)                            \
   V(Float64Mod)                            \
   V(Float64Atan2)                          \
   V(Float64Pow)                            \
   V(Float64InsertLowWord32)                \
   V(Float64InsertHighWord32)               \
-  V(IntPtrAdd)                             \
   V(IntPtrAddWithOverflow)                 \
-  V(IntPtrSub)                             \
   V(IntPtrSubWithOverflow)                 \
   V(IntPtrMul)                             \
   V(Int32Add)                              \
   V(Int32AddWithOverflow)                  \
   V(Int32Sub)                              \
   V(Int32Mul)                              \
   V(Int32MulWithOverflow)                  \
   V(Int32Div)                              \
   V(Int32Mod)                              \
   V(WordOr)                                \
@@ skipping 168 matching lines @@
                     Node* value);
 
   // Store a value to the root array.
   Node* StoreRoot(Heap::RootListIndex root_index, Node* value);
 
 // Basic arithmetic operations.
 #define DECLARE_CODE_ASSEMBLER_BINARY_OP(name) Node* name(Node* a, Node* b);
   CODE_ASSEMBLER_BINARY_OP_LIST(DECLARE_CODE_ASSEMBLER_BINARY_OP)
 #undef DECLARE_CODE_ASSEMBLER_BINARY_OP
 
+  Node* IntPtrAdd(Node* left, Node* right);
+  Node* IntPtrSub(Node* left, Node* right);
+
   Node* WordShl(Node* value, int shift);
   Node* WordShr(Node* value, int shift);
   Node* Word32Shr(Node* value, int shift);
 
 // Unary
 #define DECLARE_CODE_ASSEMBLER_UNARY_OP(name) Node* name(Node* a);
   CODE_ASSEMBLER_UNARY_OP_LIST(DECLARE_CODE_ASSEMBLER_UNARY_OP)
 #undef DECLARE_CODE_ASSEMBLER_UNARY_OP
 
   // Changes an intptr_t to a double, e.g. for storing an element index
@@ skipping 190 matching lines @@
   ZoneSet<CodeAssemblerVariable::Impl*> variables_;
 
   DISALLOW_COPY_AND_ASSIGN(CodeAssemblerState);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_CODE_ASSEMBLER_H_