[mlir][linalg] Fix to Elementwise Fusion when preserving results (#149843)

In the linalg ElementwiseOpFusion transform, a pre-requisite for the
fusion between a producer and consumer op is that the producer's output
indexing map associated to the result to be fused must be invertible
(e.g. a simple permutation).
Before this patch, only the first output indexing map was being checked;
this bug produced issues when the operand to fuse was not the 1st result
of the producer op. For example, this situation arises when the producer
op has multiple results because it's the result of previous fusions
where the original result had been preserved: in these cases, the pass
ought to check the indexing map of the result being fused, which is not
necessarily the 1st one.

Signed-off-by: Fabrizio Indirli <Fabrizio.Indirli@arm.com>

0 files changed, 0 insertions, 0 deletions