[mlir][linalg] Add makeComposedPadHighOp.

Add the makeComposedPadHighOp method which creates a new PadTensorOp if necessary. If the source to pad is actually the result of a sequence of padded LinalgOps, the method checks if padding is needed or if we can use the padded result of the padded LinalgOp sequence directly.

Example:
```
%0 = tensor.extract_slice %arg0 [%iv0, %iv1] [%sz0, %sz1]
%1 = linalg.pad_tensor %0 low[0, 0] high[...] { linalg.yield %cst }
%2 = linalg.matmul ins(...) outs(%1)
%3 = tensor.extract_slice %2 [0, 0] [%sz0, %sz1]
```
when padding %3 return %2 instead of introducing
```
%4 = linalg.pad_tensor %3 low[0, 0] high[...] { linalg.yield %cst }
```

Depends On D114161

Reviewed By: nicolasvasilache, pifon2a

Differential Revision: https://reviews.llvm.org/D114175

0 files changed, 0 insertions, 0 deletions