On Sun, Oct 14, 2012 at 10:05 PM, Steven Bosscher <stevenb....@gmail.com> wrote: > Hello, > > This patch is a back-port of one of the scalability improvements I > made to perform, well, maybe not well but at least not so poorly on > the test case of PR54146, which has an extremely large function. > > The problem in ifcvt.c has two parts. The first is that clearing > several arrays of size(max_reg_num) for every basic block slowed down > things. The second part is that this memory was being allocated with > alloca, so that a sufficiently large function could blow out the > stack. > > The latter problem was now also found by a user trying to compile a > sensible and well-known piece of software (see > http://gcc.gnu.org/ml/gcc/2012-10/msg00202.html). This code compiles > with older GCC releases, so this problem is a regression. To fix the > problem in GCC 4.7, I'd like to propose this back-port. > > Bootstrapped&tested with release and default development checking on > x86_64-unknown-linux-gnu and on powerpc64-unknown-linux-gnu. The patch > has also already spent more than two months on the trunk now without > problems. OK for the GCC 4.7 release branch? Maybe also for the GCC > 4.6 branch after testing?
Ok for 4.7, I prefer to not backport this to 4.6 at this point. Thanks, Richard. > Ciao! > Steven
