On 07/01/14 13:58, Marc Glisse wrote:
I don't think we can define any reasonable semantics for &+. My
recommendation would be for this to be considered a hard error.
Uh? The doc explicitly says "An input operand can be tied to an
earlyclobber operand" and goes on to explain why that is useful. It
avoids using the same register for other input when they are identical.
Nothing like making a statement on the internet to bring out folks more
"in the know" to refute what was said :-)
Reviewing that paragraph, it does sound vaguely familiar. So the
backend developer explicitly ties the input to an earlyclobbered output
and the other inputs are marked as conflicting.
I guess I can see how that is helpful, though I wonder how often it is
helpful in practice.
Regardless, I stand corrected :-)
jeff
