[llvm] [RISCV][MC] Prioritize features in MultiMismatchFallback (PR #215737)

[Alexander Richardson via llvm-commits]

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@@ -1866,6 +1866,15 @@ class AsmParser {
   // messages.
   bit ReportMultipleNearMisses = false;
 
+  // PrioritizeFeatureInMultipleNearMisses -
+  // When 0, operand near-misses and feature near-misses are treated equally
+  // in the multiple near-miss reporting path.
+  // When 1, feature near-misses are prioritized over operand near-misses
+  // when multiple near-misses are recorded for the same instruction encoding,
+  // so that diagnostics point to the missing extension rather than a operand
+  // mismatch. Only effective when ReportMultipleNearMisses is also 1.
+  bit PrioritizeFeatureInMultipleNearMisses = false;
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arichardson wrote:

Do we even need this option? I think getting the missing feature error is generally more useful.

https://github.com/llvm/llvm-project/pull/215737