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Re: Incorrect code using gcc 2.8.x for Motorola 5200 Coldfire

  In message <>you write:
  > Correct.  I didn't state that clearly enough.  Upon reading the
  > 68020, 68030, 68040, 5202, 5206 and 5307 programmers references;
  > it appears that a "movea.w" is not allowed on any of these
  > processors (i.e. a byte move into or out of an address register).
Err, "movea.w" != byte.  

I spent a little more time looking at the code, and for other m68k
variants we only disallow QImode loads/stores to/from address registers.

For a byte copy we'll actually generate a word sized copy.  So, does
the 5307 allow mov.w #<immedaite>,aX or mov.w reg0,reg1 where 
reg0 and/or reg1 are address registers?

If so, then the better solution is easy.  We fix the constraints to disallow
QImode load/stores to/from address regs and tweak output_movve_qimode
to use the ".w" extension instead of hte ".b" extension for something
which references an address reg.

[ I say better since we would still allow QImode values to be
  allocated to address regs, which has advantages for register
  allocation. ]



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