Changes

[clang-format] Fix AlignConsecutiveDeclarations handling of pointers

This is a bug fix of https://bugs.llvm.org/show_bug.cgi?id=49175

The expected code format:

unsigned int*       a;
int*                b;
unsigned int Const* c;

The actual code after formatting (without this patch):

unsigned int* a;
int*          b;
unsigned int Const* c;

Differential Revision: https://reviews.llvm.org/D97137

[lld-macho] check minimum header length when opening linkable input files

Bifurcate the `readFile()` API into ...
* `readRawFile()` which performs no checks, and
* `readLinkableFile()` which enforces minimum length of 20 bytes, same as ld64

There are no new tests because tweaks to existing tests are sufficient.

Differential Revision: https://reviews.llvm.org/D97610

[X86] Add back SSE check prefix for vec-umulo.ll. Regenerate vec-smulo.ll. NFC

Simon modified the check prefixes in these tests while D97160
was pending review. When D97160 was commited it wasn't updated
it merge cleanly, but didn't comprehend the check prefix changes.

[mlir][linalg] Generate additional interfaces for named ops.

* Adds ContractionOpInterface to polymorphic_matmul.

Differential Revision: https://reviews.llvm.org/D97601

[mlir][linalg] Add symbolic type conversion to linalg named ops.

This enables this kind of construct in the DSL to generate a named op that is polymorphic over numeric type variables `T` and `U`, generating the correct arithmetic casts at construction time:

```
@tc_def_op
def polymorphic_matmul(A=TensorDef(T1, S.M, S.K),
                       B=TensorDef(T2, S.K, S.N),
                       C=TensorDef(U, S.M, S.N, output=True)):
  implements(ContractionOpInterface)
  C[D.m, D.n] += cast(U, A[D.m, D.k]) * cast(U, B[D.k, D.n])
```

Presently, this only supports type variables that are bound to the element type of one of the arguments, although a further extension that allows binding a type variable to an attribute would allow some more expressiveness and may be useful for some formulations. This is left to a future patch. In addition, this patch does not yet materialize the verifier support which ensures that types are bound correctly (for such simple examples, failing to do so will yield IR that fails verification, it just won't yet fail with a precise error).

Note that the full grid of extensions/truncation/int<->float conversions are supported, but many of them are lossy and higher level code needs to be mindful of numerics (it is not the job of this level).

As-is, this should be sufficient for most integer matmul scenarios we work with in typical quantization schemes.

Differential Revision: https://reviews.llvm.org/D97603

NFC: Adds labels to a linalg test and extend a missing case.