Messages in this thread |  | | Date | Fri, 09 May 2003 15:22:52 -0700 | From | Ulrich Drepper <> | Subject | Re: hammer: MAP_32BIT |
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Timothy Miller wrote:
> If your program is capable of handling an address with more than 32 > bits, what point is there giving a hint? Either your program can handle > 64-bit pointers or it cannot. Any program flexible enough to handle > either size dynamically would expend enough overhead checking that it > would be worse than if it just made a hard choice.
Look at the x86-64 context switching code. If memory addressed by the GDT entries has a 32-bit address it uses a different method than for cases where the virtual address has more than 32 bits. This way of handling GDT entries is faster according to ak. So, it's not a correctness thing, it's a performance thing.
- -- - --------------. ,-. 444 Castro Street Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA Red Hat `--' drepper at redhat.com `--------------------------- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (GNU/Linux)
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