On 11/09/2010 10:22 AM, Joern Rennecke wrote:
Quoting roy rosen <roy.1ro...@gmail.com>:
What is the difference when writing define_insn_and_split?
From what I understood from the docs then if there is such an insn
then the split does not occur so it would simply match it as an insn
without splitting and at the end would print the #?
Can you please elaborate?
The combiner (and other passes) would match it as an insn, but ordinary
splitter passes, e.g. before scheduling, will still split it.
As I understand it, this will also give combine the ability to do
two->two (and two->N) transformations, though indirectly through the
temporary insn. Given this, could you explain further the benefits of
combiner-split define_split vs. define_insn_and_split.
Paolo
