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Re: ssa bootstrap problem on x86 (cmpstrsi_1 pattern)


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

    Richard> On Thu, Jul 27, 2000 at 01:10:11PM -0700, Mark Mitchell
    Richard> wrote:
    >> I think we need to bite the bullet and get the CLOBBERs out of
    >> there; otherwise, we are forced to do some kind of dataflow
    >> anlaysis in SSA...

    Richard> Not at all.  We have a register set, once, to an
    Richard> unspecified value.  That unspecified value is "valid"
    Richard> everywhere, just as with a register set to a useful
    Richard> value.

In Geoff's examples, I believe it was SET once, and then CLOBBERed.
Did I misread?

--
Mark Mitchell                   mark@codesourcery.com
CodeSourcery, LLC               http://www.codesourcery.com

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