Add missing splitter for H8

While testing a minor optimization on the H8 my builds failed due to
failure to split a zero-extended memory load.    That particular pattern
is a bit special on the H8 in that it's split at assembly time primarily
to get the length computations correct.  Arguably that alternative should
go away completely, but I haven't really looked into that.

Anyway, with the final-asm split we obviously need to match a define_split
somewhere.  But none was ever written after adding CCZN optimizations.  So
if we had a zero extend of a memory operand and it was used to eliminate
a compare, then we'd abort at final asm time.

Regression tested (in conjunction with various other in-progress patches) on
H8 without regressions.

gcc/
	* config/h8300/extensions.md (CCZN setting zero extended load): Add
	missing splitter.

0 files changed, 0 insertions, 0 deletions