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Re: [PATCH 204/236] final.c: Use rtx_sequence


On 08/15/14 18:56, David Malcolm wrote:
On Fri, 2014-08-15 at 18:38 -0400, Trevor Saunders wrote:

i.e. back to just a GET_CODE check again (albeit with a new local, of
the subclass ptr type; I don't know how well our optimizations handle
that yet: the idea that a local ptr X is either equal to another local
ptr Y or is NULL.  Does our value-numbering cope with this, where one
ptr is a subclass of another?).
I'm not sure what you're asking. If you can give me the gimple I can probably answer ;-)

In general the gimple optimizers don't care/know about class relationships. So if the pointers point to the same object, but have different types, it's likely we won't optimize away things as well as we'd like.
jeff


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