Hi Christophe, On Tue, May 07, 2019 at 01:31:39PM +0000, Christophe Leroy wrote: > Cache instructions (dcbz, dcbi, dcbf and dcbst) take two registers > that are summed to obtain the target address. Using '%y0' argument > gives GCC the opportunity to use both registers instead of only one > with the second being forced to 0.
That's not quite right. Sorry if I didn't explain it properly. "m" allows all memory. But this instruction only allows reg,reg and 0,reg addressing. For that you need to use constraint "Z". The output modifier "%y0" just makes [reg] (i.e. simple indirect addressing) print as "0,reg" instead of "0(reg)" as it would by default (for just "%0"). Segher
