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Re: i386 CONST_COSTS take 2
> - Set the cost of simple constants for x86 back to one
> - Make gcse consider them (look for want_to_gcse_p)
> - Add a check to gcse them only if this results in an overall cost saving.
> Maybe taking lifetime into account / register pressure.
Shouldn't we be be able to teach reload and register allocator to eliminate
the cost completely? We are able to re-incarnate such values w/o spilling,
so proper tunning of preferences should do the trick.
What I worry about are the extra instructions in sequences of two instructions
with same constant, where extra load is just a lose. These are common.
Honza