[llvm] [DAGCombine] Remove oneuse restrictions for RISCV in folding (shl (add_nsw x, c1)), c2) and folding (shl(sext(add x, c1)), c2) in some scenarios (PR #101294)

[Simon Pilgrim via llvm-commits]

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@@ -60673,3 +60673,20 @@ Align X86TargetLowering::getPrefLoopAlignment(MachineLoop *ML) const {
     return Align(1ULL << ExperimentalPrefInnermostLoopAlignment);
   return TargetLowering::getPrefLoopAlignment();
 }
+
+bool X86TargetLowering::isDesirableToCommuteWithShift(
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RKSimon wrote:

remove this? it looks like it matched the generic implementation

https://github.com/llvm/llvm-project/pull/101294