The stripmineSink helper splices loop body operations into a new inner
scf.for that has no iter_args. When the target loop carries iter_args,
values yielded by the spliced body are moved inside the inner loop, but
the outer loop's yield terminator still references those values,
creating an SSA invariant violation. In debug builds this triggers the
assertion
use_empty() && "Cannot destroy a value that still has uses\!"
when the outer RewriterBase tries to erase the now-broken operations.
Fix: in extractFixedOuterLoops, skip the strip-mining transformation if
any of the collected perfectly-nested loops have iter_args.
Add a regression test to parametric-tiling.mlir.
Fixes#129044
Assisted-by: Claude Code
b78ceef43e