[llvm] [GlobalISel][TableGen] Support Intrinsics in MIR Patterns (PR #79278)

[Matt Arsenault via llvm-commits]

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@@ -521,14 +522,16 @@ void CombineRuleOperandTypeChecker::getInstEqClasses(
   //    - Iterating over the map, filtering types we don't like, and just adding
   //      the array of Operand Indexes to \p OutTECs.
 
-  // We can only do this on CodeGenInstructions. Other InstructionPatterns have
-  // no type inference information associated with them.
+  // We can only do this on CodeGenInstructions that aren't intrinsics. Other
+  // InstructionPatterns have no type inference information associated with
+  // them. Intrinsics also don't have any constraints to guide inference.
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arsenm wrote:

This isn't entirely true? The signatures do support some level of related parameter constraints 

https://github.com/llvm/llvm-project/pull/79278