Known as Carakan, the new engine was designed to put speedy performance first, eschewing the emphasis on a small memory footprint that dictated the design of previous components.
"This has traditionally been a correct trade-off on many of the platforms Opera runs on," wrote Opera developer Jens Lindström.
"The Web is a changing environment however, and tomorrow's advanced web applications will require faster ECMAScript execution, so we have now taken on the challenge to once again develop the fastest ECMAScript engine on the market."
To boost speed, Lindström said that the developers focused on changing three components of the engine to maximise performance.
Bytecode will be processed with a register-based system rather than the stack-based system used by the current engine.
This will reduce the amount of data that needs to be copied and processed, explained Lindström.
Developers also looked to speed up performance by generating larger amounts of native code and streamlining the handling of objects within script code.
Lindström noted that development of the Carakan engine was still ongoing with certain components, such as native code generation, not yet ready for extensive testing. No possible release date was given, though developers cautioned users not to expect Carakan in the upcoming Opera 10 release.
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