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

[Peter Waller via llvm-commits]

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@@ -597,14 +610,25 @@ int main(int argc, char **argv) {
           // Default case.
           WithColor::error() << toString(std::move(NewE));
         }
+        if (SkipUnsupportedInstructions) {
+          DroppedInsts.insert(&MCI);
+          continue;
+        }
         return 1;
       }
 
       IPP->postProcessInstruction(Inst.get(), MCI);
-
+      InstToInstruments.insert({&MCI, Instruments});
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peterwaller-arm wrote:

The `continue` above is dropping instructions, so it seemed logical to me to avoid inserting these dropped instructions into other data structures since they're now "gone".

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