https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93932
--- Comment #3 from Michael Meissner <meissner at gcc dot gnu.org> --- While I agree that in general, we should only use input_operand for moves and define_expands, I tend to think in the short term (GCC 10) we should just fix the case we know about. As you point out, this is used in every single place where we fold sign/zero/float extension into a load. In looking at gcc 8 and gcc 9, the variable extract patterns are mostly the same, except gcc 8 uses 'ww', etc. constraints, while gcc 9/10 uses the 'isa' attribute to eliminate the cases using power9 instructions on power8. I don't know why only V2DI/V2DF shows it up, when V4SF/V4SI/V8HI/V16QI use the same construct, and why -mcpu=power9 compiles it ok on trunk, but not gcc 9.
