[PATCH] Break dependencies in large loops containing reductions (LoopVectorize)

[Olivier Sallenave]

> I think we might want to separate the current single number into two numbers: one for ILP and once for latency. But I'm not exactly sure what you're suggesting.


It seems we don't really care about the latency alone, we just want to know about ILP. As I see it, the current number takes into account ILP (that is, latency and number of functional units), and **somehow** register pressure, like we don't want to put a big number like 12 in there.

What I need is a number which only takes into account ILP, and that is because the cost function I propose already takes register pressure into account. Typically I want to have 12 for http://reviews.llvm.org/P7/http://reviews.llvm.org/P8. What I am suggesting is to add a new TTI function to return the max ILP available.


http://reviews.llvm.org/D7514

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/