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Re: flow still deleting important labels



  In message <19990328151310.B18408@cygnus.com>you write:
  > In the first (-mgas), I don't replicate what you reported 
  > exactly.. the label hangs out until flow2.  At which point 
  > there are no references to the label whatsoever, and it 
  > gets deleted.
Weird.  I'll look further into this one since I've got hpux boxes handy.


  > So there are two choices here -- either set LABEL_PRESERVE_P
  > on things that enter the constant pool, or always garbage
  > collect the constant pool.  The later solution seems better.
Yea, always garbage collecting the pool sounds right.


  > In the second (-mno-gas), the initial rtl has the label in
  > the constant pool, but no REG_LABEL note.  So jump1 purges
  > the label.  Curious.  Looking again I see the reference in
  > the constant pool set to zero...  I'll check this some more.
Hmmm, what code is responsible for adding a REG_LABEL note to an insn
that loads the address of a label out of the constant pool?

Maybe marking labels in the pool with LABEL_PRESERVE_P isn't such a bad
idea after all.
jeff


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