Apply patterns repeatly if the function is modified
During the pattern rewrite, if the function is changed, i.e. ops created,
deleted or swapped, the pattern rewriter needs to re-scan the function entirely
and apply the patterns again, so the patterns whose root ops have been popped
out from the working list nor an immediate users of the changed ops can be
reconsidered.
A command line flag is added to set the max number of iterations rescanning the
function for pattern match. If the rewrite doesn' converge after this number,
this compiling will continue and the result can be sub-optimal.
One unit test is updated because this change fixed the missing optimization opportunities.
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PiperOrigin-RevId:
244754190