> Please, just look at those charts > > https://vmakarov.108.redhat.com/nonav/spec/comparison.html > > The compilation speed decrease without a performance improving (at least > for the default case) is really scary.
Right, I also found those charts a bit depressing, given the time and energy that have been put in the compiler since GCC 3.2.3. For example, it seems that the Tree-SSA infrastructure has brought very little benefit in terms of performance in the generic case, in exchange for a massive dump of new code. Does anyone have the beginning of an idea as to why this is so? Did GCC hit a fundamental wall some time ago, for example because of its portability? On the other hand, those efforts have not been lost, since the compiler is now much more modern in terms of infrastructure and algorithms. However, before triggering the next internal earthquake (namely LTO), we should probably try to understand what's going on (or not going on). -- Eric Botcazou
