[llvm] [LLVM] Change Intrinsic::ID to encode target and intrinsic index (PR #113576)

[Rahul Joshi via llvm-commits]

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@@ -275,7 +275,7 @@ enum {
   /// Check the operand is a specific intrinsic ID
   /// - InsnID(ULEB128) - Instruction ID
   /// - OpIdx(ULEB128) - Operand index
-  /// - IID(2) - Expected Intrinsic ID
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jurahul wrote:

My concern with making this 2 byte is: (1) won't we have files with patterns that use mix of target independent and target dependent builtins. In such cases, just encoding the 16-bit target index is not sufficient, and  (2) premature optimizations? If its really important, I'd prefer doing this as an independent change.

https://github.com/llvm/llvm-project/pull/113576