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cc0 -> CCmode questions


Segher Boessenkool schrieb:
Btw, does GCC support clobbering registers in branches (or cbranch<mode>4 for that matter)? This requirement would come up when transitioning avr to cc_mode because cbranches would live post reload.

Of course.  You cannot have *reloads* on branches, that is all.

Segher

Does this also apply to input reloads?

Suppose cbranch with constraints like

"d,r"
"n,r"

for the operands to be compared, where d is a register class that
can be compared against immediate, but registers in r can't be
compared to n in general.

For a case #2 target (only ccmode clobbers before reload), reload might
generate an input reload for the constant in the cbranch.

So this is for bidden?

Johann


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