[llvm] [llvm-mca] Abort on parse error without -skip-unsupported-instructions (PR #90474)

[Michael Maitland via llvm-commits]

michaelmaitland wrote:

> I really dislike that we are going to allow this. Can we exclude these kinds of errors from any skip-parse-errors option? Maybe we need two levels: (1) ignore all parse errors and (2) ignore parse errors because CPU did not support those instructions?

On second thought, maybe we just allow the garbage for sake of simplicity. Let users who use this option know that they can abuse it for the sake of backwards compatibility. This approach means this change is minimally invasive to maintainability of llvm-mca since we're keeping it as simple as possible.

You have my support on either approach. 

https://github.com/llvm/llvm-project/pull/90474