I think that sequence of compare + cond-jump will exists in any compiler pass.
Combine can optimize away compares, if you have other instructions that set the condition code register to useful values. This optimization will only work correctly if instructions that set or clobber the cc are properly marked.
If no instructions are marked as setting the cc (other than compares), then this will probably work, but you won't get any optimization from combine, and may get worse code than before.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com
