Hi Martin,
On 2019-11-27 19:03, Doerr, Martin wrote:
Hi Claes,
that kind of surprises me. I'd expect files which rather benefit from -O3 to be
far less than those which benefit from -Os.
Most performance critical code lives inside the code cache and is not dependent
on C++ compiler optimizations.
I'd expect GC code, C2's register allocation and a few runtime files to be the
most performance critical C++ code.
So the list of files for -Os may become long.
that might very well be the end result, and once/if we've gone down this
path long enough to see that -O3 becomes the exception, we can re-
examine the default. Changing the default and then trying to recuperate
would be hard/impossible to do incrementally.
Yeah, I think we should use native profiling information to find out what's really
going on >
Your idea to change file by file and check for performance regression makes
sense to me, though
Hopefully we don't have to do one RFE per file.. :-)
/Claes
