[llvm] [llvm-mca] Add -skip-unsupported-instructions option (PR #89733)

[Michael Maitland via llvm-commits]

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@@ -759,6 +783,11 @@ int main(int argc, char **argv) {
     ++RegionIdx;
   }
 
+  if (NonEmptyRegions == 0) {
+    WithColor::error() << "no assembly instructions found.\n";
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michaelmaitland wrote:

Can you please add test coverage for this case?

https://github.com/llvm/llvm-project/pull/89733