Re: C++ PATCH: improve performance of vbase initialization

[Mark Mitchell <mark at codesourcery dot com>]

>>>>> "Richard" == Richard Henderson <rth@cygnus.com> writes:

    Richard> On Sun, Jan 16, 2000 at 12:22:49PM -0800, Mark Mitchell
    Richard> wrote:
    >> BTW, I'm surprised that GCSE isn't able to eliminate the
    >> redundant test of edx.  Any ideas?

    Richard> We don't currently do gcse on hard registers.
    Richard> E.g. (reg:CCNO 17 flags).  It hurts the x86 port
    Richard> elsewhere too -- the clobbering of flags by arithmetic
    Richard> means that gcse is effectively crippled.

    Richard> It's something that could (perhaps easily) be addressed.
    Richard> The reason we don't handle hard regs now is that Doug
    Richard> Evans' initial implementation was on a deadline and
    Richard> didn't want to have to think about any hidden traps.

Thanks for the answers.

--
Mark Mitchell                   mark@codesourcery.com
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