Michael_fogel wrote:
(ior:SI (subreg:SI (mem/s:QI (reg/f:SI 1250) [0 <variable>.flags+0 S1 A32]) 0)
See register_operand and general_operand in recog.c. (SUBREG (MEM)) is accepted by register_operand if INSN_SCHEDULING is not defined, for historical reasons. This is something that should be fixed some day.
INSN_SCHEDULING is defined if you have any of the instruction scheduling related patterns in your md file. If this is a new port, and you haven't tried to add instruction scheduling support, then INSN_SCHEDULING won't be defined yet.
Anyways, this means that the RTL is correct, and we expect reload to fix it. The error from gen_reg_rtx implies that reload is failing, perhaps because of a bug in your port that doesn't handle (SUBREG (MEM)) correctly.
There are other legitimate cases where (SUBREG (MEM)) can occur during reload, when you have a subreg of an pseudo that did not get allocated to a hard register for instance, so even if register_operand and general_operand are changed, you still need to find and fix the bug in your port.
-- Jim Wilson, GNU Tools Support, http://www.specifix.com