Notes:
- pc and npc are left unmodified, since they can point to out-of-TB
jump targets.
- Got rid of last_pc in gen_intermediate_code(), using base.pc_next
instead. Only update pc_next (1) on a breakpoint (so that tb->size
includes the insn), and (2) after reading the current instruction
from memory. This allows us to use base.pc_next in the BP check,
which is what the translator loop does.
Backports commit af00be490b30d7f576d12ac7b2bc5406ca6fda3f from qemu