ssa bootstrap problem on x86 (cmpstrsi_1 pattern)

[Mark Mitchell]

>>>>> "Joern" == Joern Rennecke <amylaar@cygnus.co.uk> writes:

    >> The only reason clobbers appear this early in the compiler is
    >> that GCC generates machine-specific code very early.  There is
    >> no operation

    Joern> That is not true.  When gcc synthesizes a move that is
    Joern> wider than the widest one available in the machine
    Joern> description, it first clobbers the destination, then does a
    Joern> series of moves into SUBREGs of the destination.

But, again, isn't that a machine-specific issue?  These moves could be
represented directly as a SET and then resolved to an operation
involving SUBREGs and CLOBBERs later.

--
Mark Mitchell                   mark@codesourcery.com
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