modarray causes LIR failure

Bugzilla Link	750
Created on	Sep 26, 2010 17:48
Version	svn
OS	Linux
Architecture	PC
Attachments	crud.reallyslow.sac

Extended Description

Created an attachment (id=757)
source code to reproduce fault
The attached SAC code, if compiled with -DGOSLOW, ends up recomputing
the Boolean vector on every iteration through the indexof (iotaBBI) loop.
This is A Bad Thing, if you have any interest in (good) performance.
I just came across thie by accident, while lamenting the compiler's
inability to fold a WL into a FOR-loop.