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Re: splitting const_int's
On Tue, May 20, 2008 at 2:47 PM, Paul Brook <paul@codesourcery.com> wrote:
> Does this work reliably for straight mov patterns and during reload? Sounds
> like in the general case it would need secondary reloads, which is a whole
> lot of extra magic.
Hmm, right. Maybe something like what rs6000 does:
; List r->r after r->"o<>", otherwise reload will try to reload a
; non-offsettable address by using r->r which won't make progress.
(define_insn "*movdi_internal32"
[(set (match_operand:DI 0 "nonimmediate_operand" "=o<>,r,r,*f,*f,m,r")
(match_operand:DI 1 "input_operand" "r,r,m,f,m,f,IJKnGHF"))]
And then in the split it does:
/* Move register range backwards, if we might have destructive
overlap. */
in rs6000_split_multireg_move.
-- Pinski