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Re: Help with "unable to generate reloads for" atomic_exchangesi
On Tue, Sep 24, 2019 at 11:33:56AM -0500, William Tambe wrote:
> On Tue, Sep 24, 2019 at 10:52 AM Segher Boessenkool
> <segher@kernel.crashing.org> wrote:
> > Don't use "+", just use matching constraints, like the "0" you already
> > have, but then "1"? Like
> >
> > (define_insn "atomic_exchangesi"
> > [(set (match_operand:SI 0 "register_operand" "=r,r")
> > (match_operand:SI 1 "memory_operand" "B,W"))
> > (set (match_operand:SI 2 "memory_operand" "=1,1")
> > (unspec:SI
> > [(match_operand:SI 3 "register_operand" "0,0")
> > (match_operand:SI 4 "const_int_operand")]
> > 0))]
> >
> Per https://gcc.gnu.org/onlinedocs/gccint/Standard-Names.html ,
> atomic_exchangesi only has 4 operands instead of 5 operands as it is
> the case in your example.
Yeah. So do a define_expand for atomic_exchangesi that has only the four
operands, and which expands to your actual machine pattern, which then is
a separate define_insn?
Segher