[llvm] [RISCV] Strength reduce mul by 2^M - 3/5/9 (PR #88993)

[Philip Reames via llvm-commits]

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@@ -13447,7 +13447,6 @@ static SDValue expandMul(SDNode *N, SelectionDAG &DAG,
   case 21:
   case 25:
   case 27:
-  case 29:
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preames wrote:

It was a mistake to start with.  We don't actually have a TD pattern for 29.

https://github.com/llvm/llvm-project/pull/88993