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Re: [tree-ssa] PATCH to improve optimization at ssa rewrite time


On Tue, 2003-05-13 at 15:09, Jason Merrill wrote:

> This is very useful in conjunction with expression temporaries, which
> produce a lot of redundant statements.
> 
Cool.  Thanks!

> Oddly, this doesn't work for plain "i = 42".  Something to look into.
> 
Because 'i = 42' is not cached in the avail_exprs table.  It's stored in
the const_and_copies table for constant/copy propagation.  Both tables
are accessed in a different way.  For available expressions, we use the
expression (RHS) as index, for constant and copies we use the variable
on the LHS as index.


Diego.


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