This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] Fix PR 13987, compile time slow down on powerpc-apple-darwin


I think the comment is OK. I don't think we need to override this.

OK.


We are looking for an integer which is fast even when targetting a
64-bit machine.  I think your suggestion of HOST_FAST_INT is
reasonable.  When targetting a 32-bit machine, HOST_FAST_INT and
HOST_WIDE_INT would normally be the same.  When targetting a 64-bit
machine, HOST_WIDE_INT must be 64 bits, but HOST_FAST_INT might be 32
bits.

So (unsigned) long will always work, you think? Or does it need a platform-specific override? I can only think of 8- or 16-bit host machines wanting that; and I don't really care about the speed of compiling _on_ such a machine ;-)

There are popular targets which require a 64-bit HOST_WIDE_INT--
powerpc, mips, x86_64--so I think HOST_FAST_INT is a reasonable idea
to use in bitmap operations.

That's what I did to speedup bitmap.[ch], but I hardcoded it to unsigned long. Will convert to HOST_FAST_INT and sbitmap too, and whatever else I find (some register set stuff at least, I think).


Segher



Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]