Implement experimental exponentiation operator via desugaring

src/parser.cc

 // Copyright 2012 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.
 
 #include "src/v8.h"
 
 #include "src/api.h"
 #include "src/ast.h"
 #include "src/bailout-reason.h"
 #include "src/base/platform/platform.h"
@@ skipping 493 matching lines @@
         uint32_t value = DoubleToUint32(x_val) >> shift;
         *x = factory->NewNumberLiteral(value, pos);
         return true;
       }
       case Token::SAR: {
         uint32_t shift = DoubleToInt32(y_val) & 0x1f;
         int value = ArithmeticShiftRight(DoubleToInt32(x_val), shift);
         *x = factory->NewNumberLiteral(value, pos);
         return true;
       }
+      case Token::EXP: {
+        double value = power_helper(x_val, y_val);
+        *x = factory->NewNumberLiteral(value, pos);
+        return true;
+      }
       default:
         break;
     }
+  } else if (op == Token::EXP) {
+    Zone* zone = parser_->zone();
+
+    // Desugar exponentiation to runtime call
+    ZoneList<Expression*>* args = new (zone) ZoneList<Expression*>(2, zone);
+    args->Add(*x, zone);
+    args->Add(y, zone);
+    *x = factory->NewCallRuntime(
+        parser_->ast_value_factory()->math_pow_string(), NULL, args, pos);
+    return true;
   }
   return false;
 }
 
 
 Expression* ParserTraits::BuildUnaryExpression(Expression* expression,
                                                Token::Value op, int pos,
                                                AstNodeFactory* factory) {
   DCHECK(expression != NULL);
   if (expression->IsLiteral()) {
@@ skipping 281 matching lines @@
   set_allow_harmony_arrow_functions(FLAG_harmony_arrow_functions);
   set_allow_harmony_numeric_literals(FLAG_harmony_numeric_literals);
   set_allow_harmony_classes(FLAG_harmony_classes);
   set_allow_harmony_object_literals(FLAG_harmony_object_literals);
   set_allow_harmony_templates(FLAG_harmony_templates);
   set_allow_harmony_sloppy(FLAG_harmony_sloppy);
   set_allow_harmony_unicode(FLAG_harmony_unicode);
   set_allow_harmony_computed_property_names(
       FLAG_harmony_computed_property_names);
   set_allow_harmony_rest_params(FLAG_harmony_rest_parameters);
+  set_allow_harmony_exponentiation(FLAG_harmony_exponentiation);
   set_allow_strong_mode(FLAG_strong_mode);
   for (int feature = 0; feature < v8::Isolate::kUseCounterFeatureCount;
        ++feature) {
     use_counts_[feature] = 0;
   }
   if (info->ast_value_factory() == NULL) {
     // info takes ownership of AstValueFactory.
     info->SetAstValueFactory(new AstValueFactory(zone(), hash_seed));
     ast_value_factory_ = info->ast_value_factory();
   }
@@ skipping 3224 matching lines @@
     reusable_preparser_->set_allow_harmony_classes(allow_harmony_classes());
     reusable_preparser_->set_allow_harmony_object_literals(
         allow_harmony_object_literals());
     reusable_preparser_->set_allow_harmony_templates(allow_harmony_templates());
     reusable_preparser_->set_allow_harmony_sloppy(allow_harmony_sloppy());
     reusable_preparser_->set_allow_harmony_unicode(allow_harmony_unicode());
     reusable_preparser_->set_allow_harmony_computed_property_names(
         allow_harmony_computed_property_names());
     reusable_preparser_->set_allow_harmony_rest_params(
         allow_harmony_rest_params());
+    reusable_preparser_->set_allow_harmony_exponentiation(
+        allow_harmony_exponentiation());
     reusable_preparser_->set_allow_strong_mode(allow_strong_mode());
   }
   PreParser::PreParseResult result = reusable_preparser_->PreParseLazyFunction(
       language_mode(), function_state_->kind(), logger);
   if (pre_parse_timer_ != NULL) {
     pre_parse_timer_->Stop();
   }
   return result;
 }
 
@@ skipping 1413 matching lines @@
     } else {
       const uc16* data = reinterpret_cast<const uc16*>(raw_string->raw_data());
       running_hash = StringHasher::ComputeRunningHash(running_hash, data,
                                                       raw_string->length());
     }
   }
 
   return running_hash;
 }
 } }  // namespace v8::internal