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Re: [PATCH] Fix PR middle-end/28690, indexed load/store performance + reload bug


Peter Bergner wrote:

> In this case, the first "find_reg (allocno_order[i], 0, 0, 0, 0)" fails to
> find a register, so we're forced to find a register in an alternate class.
> For pseudo 238, reg_alternate_class() returns ALL_REGS, so we call
> "find_reg (allocno_order[i], 0, 1, 0, 0)" and it's this call that we get
> reg 65.  I'll dig in a little more to see why we didn't get a reg during
> the first call to find_reg.

That will most likely be simply because all registers in that class are
already in use.

The interesting question is, why is reg_alternate_class for the pseudo
ALL_REGS if there's an instruction that doesn't accept it ...

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com


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