ucbesvax.turner@ucbcad.UUCP (07/12/83)
#N:ucbesvax:12800005:000:781 ucbesvax!turner Jul 11 19:06:00 1983 Does anyone out there know of a processor with a "loop branch point" register--i.e., a register which holds a pc-value for continuation of loops? To give a simple example of string copy: ... ! a0,a1 with char pointers: lea bpr, pc ! next instruction loc -> loop branch point movb @a0+, @a1+ ! copy byte, post-incrementing loopnz ! pc <- lpb if byte was nonzero ... Of course, I suppose you could just say "jnz a2" instead, using a2 as a branch-point-register, if you really wanted to get into tricky code optimizations. It seems preferable to garbaging up the architecture with special registers and instructions. As an alternative question, then: does anyone know of code generators which do such optimizations? Michael Turner ucbvax!ucbesvax.turner