Bug 174275 – [JSC] Add support overriding of the runtime error messages without adding new op_codes

• Status: NEW
• Component: JavaScriptCore

[GSkachkov]

JSC should support overriding of the runtime error messages, to show more suitable error message. i.e. https://webkit.org/b/169293. There is expected more such types of modification of already existed error messages and this should be done without adding new op_codes check, to prevent performance degradation.
The idea is use some metadata in CodeBlock, and after throwing check if error message that was thrown from some byte code operation was overridden in CodeBlock metadata.

[GSkachkov]

Ohh, wrong link to example, should be https://webkit.org/b/1173381