[llvm] [InstCombine] Allow folds of shifts by constants for scalable vectors again (PR #132522)

[Yingwei Zheng via llvm-commits]

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@@ -428,7 +428,10 @@ Instruction *InstCombinerImpl::commonShiftTransforms(BinaryOperator &I) {
         return R;
 
   Constant *CUI;
-  if (match(Op1, m_ImmConstant(CUI)))
+  if (match(Op1, m_Constant(CUI)) &&
+      (!isa<ConstantExpr>(CUI) ||
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dtcxzyw wrote:

Can you add a fixme here to note that we should remove this special case after we use ConstantInt to represent a scalable vector splat by default?


https://github.com/llvm/llvm-project/pull/132522