Some DImode rotate-right-and-mask can be implemented best with a rlwinm
instruction: those that could be a lshiftrt instead of a rotatert, while
the mask is not right-aligned. Why the rotate in the testcase is not
optimised to a plain shift is another question, but we need to handle
it here anyway. We compute the shift amount for a 64-bit rotate. This
is 32 too high in this case; if we print using %h that is masked out (and
this doesn't silently let through invalid instructions, everything is
checked by rs6000_is_valid_shift_mask which is much more thorough).
PR target/69946
* config/rs6000/rs6000.c (rs6000_insn_for_shift_mask): Print rlwinm
shift amount using %h. Add comment.
gcc/testsuite/
* gcc.target/powerpc/pr69946.c: New file.
From-SVN: r233755
