LIR ineffective in opt cycles

Bugzilla Link	860
Created on	Aug 21, 2011 09:44
Version	svn
OS	Linux
Architecture	PC
Attachments	lir.sac

Extended Description

When compiling the unit test testsuite/optimizations/al/lir.sac
AL identifies the loop invariant variables in the first opt cycle
and rearranges the multi-operand expression accordingly. 
However, none of the LIRs in the two opt cycles actually removed the
loop invariant expression and, hence, it is identified again and again
by AL. Only the final off-cycle application of LIR does its job. In a
less trivial example that, of course, would be too late for other
optimisations to benefit.
Funny enough, despite the fact that lir and wlir go together (as they
should not) the similar wlir.sac unit test works fine.