Patch for scan_loop [Re: EGCS EXTREME optimization times...]

Michael Hayes m.hayes@elec.canterbury.ac.nz
Sun Feb 28 18:15:00 GMT 1999


Jeffrey A Law writes:
 >   > 
 >   > 	* loop.c (scan_loop): Call reg_in_basic_block_p before
 >   > 	loop_reg_used_before_p.
 > This is fine.  I'm going to install it on the egcs-1.1 branch, can you please
 > install it into the mainline sources?

Done, I also added the comment:

      ??? Note we have quadratic behaviour here, mitigated
      by the fact that the previous test will often fail for
      large loops.  Rather than re-scanning the entire loop
      each time for register usage, we should build tables
      of the register usage and use them here instead. 

Michael.



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