1945651 - [meta] Slow number-crunchy JS code

Status: NEW

(Core :: JavaScript Engine: JIT, task, P3)

Description

[Iain Ireland [:iain]]

Since moving from IonBuilder to WarpBuilder, we are slower on a particular style of number-crunchy code, often involving looping over arrays doing math of some sort, where trimming a few instructions from a hot inner loop can be a big deal. (WarpBuilder adds guards in places where Ion would have relied on TI and constraints.) This kind of code is over-represented in benchmarks and under-represented in user code, so we haven't put a high priority on fixing this, but at the very least it's worth having a place to keep track of examples.