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Re: [PATCH] New code size estimate


Ref: http://gcc.gnu.org/ml/gcc-patches/2005-02/msg01796.html

> 	* tree-inline.c (estimate_num_insns_1): Ignore stores to decls with
> 	ignored flag set.

Someone still has to explain why this makes sense.  All large
expressions will now suddenly look really small, if I understand
this change correctly.  For example, say you have,

x = a + b + c + d + e + .... + z;

then the equivalent GIMPLE will look something like,

t2 = a + b;
t3 = t2 + c;
...
...
x = t25 + z;

and all the "t[0-9]+" temporaries would result in real code being
generated, but their assignments would be ignored if this patch is
applied, because all temporaries would have DECL_IGNORED set on
them.  Ignoring them would be not quite sane IMHO. Am I missing
something here?

Gr.
Steven




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