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Re: i386 performance problem due to regmove.c change


|   > I seem to be seeing around a 3 percent performance hit when
|   > running the crafty chess benchmark and the Brl-Cad raytracing
|   > benchmarks on an Intel Pentium II with:
|   > 
|   > Thu Jun 11 14:50:02 1998  Michael Meissner  <meissner@cygnus.com>
|   > 
|   > 	* regmove.c (regmove_optimize): If we can't replace the
|   > 	destination in an insn that sets the source, generate an explicit
|   > 	move of the source to the destination.
|   > 	(copy_src_to_dest): New function.
|   > 
|   > installed.  If I remove this patch then life gets better (not to
|   > mention faster :-).
| I would be very curious to know if this performance regression went
| away after my changes to recompute register set/reference counts.

Also there was a fix on June 15th that helped things along.  If you could
compile the source that slows down with the new regmove using the -save-temps
option and send us the .i or .ii file, it would be helpful.


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