This is the mail archive of the gcc@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: powercp-linux cross GCC 4.2 vs GCC 4.0.0: -Os code size regression? [Emcraft #11717]

David Edelsohn wrote:
Andrew Haley writes: 

Andrew> I suspect that the real reason for the change in save/restore is because
Andrew> not using lmw/stmw is faster.  That's just a guess though.  gcc could probably
Andrew> be fixed to use ldmw/stmw if -Os is used.

Andrew> Anyway, now we've found something specific this is for the ppc maintainer to comment.

	GCC does use load/store multiple and load/store string
instructions if -Os is used, but not when the sequence is broken up by a
fixed register.

Err, why not?

Thanks,
Andrew.

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