JavaScript:SpiderMonkey:Context Threading

Context threading is an interpreter implementation technique that aligns the interpreter's virtual PC with the real PC, to optimize branch prediction. SpiderMonkey needs it. Challenges:

• Preserving the SpiderMonkey Debugger API.
• Preserving the JS_SetBranchCallback API.
• Recoding bytecodes as necessary to improve icache utilization.
• Dealing with goto out; and any other such jumps in the interpreter.

/be