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Re: insn does not satisfy its constraints
Hi!
Am 05.10.2007 um 21:48 schrieb Rask Ingemann Lambertsen:
*** 66? This is impossible!! There is no register set that contains
that register!
Stack, frame or argument pointer?
No, they are address registers and they are FIXED, that' why they
are not in register sets Ax.
You should have a class which is the union of the Rx and Ax
classes,
placed somewhere between Ax and GENERAL. If you have instructions
which take
both Rx and Ax, define a constraint for this new class.
Basically, such a class exist, but not used. But even if I change
such a class nothing changes.
Is your REGNO_REG_CLASS() correct?
Yes.
*** Why was this movsi instruction (insn 21) inserted? It should move
R0 to an address register.
The reload pass inserted insn 21 (this is the "Reload 0" above)
before
insn 8 because it found that register R0 was no good for the
address in insn
8. Unfortunately, it picked R2 which isn't any good either.
But that's what BASE_REG_CLASS id for.
There seems to be a problem with my mov<mode> instruction?
...
Replace the first four alternatives with just one using the
combined
Rx+Ax class from above. Better yet, since the fifth alternative r-
>r should
cover it and the instruction is the same, try deleting the first four
alternatives.
There is no r->r, but I replaced all Rx / Ax alternatives by r: no
change!
What is your REGISTER_MOVE_COST? Just wondering.
// Macro: REGISTER_MOVE_COST (MODE, FROM, TO)
#define REGISTER_MOVE_COST(MODE, FROM, TO) 1
// Macro: MEMORY_MOVE_COST (MODE, CLASS, IN)
#define MEMORY_MOVE_COST(MODE, CLASS, IN) 2
// Macro: BRANCH_COST
#define BRANCH_COST 2
Thanks,
Boris