[llvm] [Matrix] Propagate shape information through PHI insts (PR #141681)

[Florian Hahn via llvm-commits]

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@@ -414,6 +416,33 @@ class LowerMatrixIntrinsics {
         addVector(PoisonValue::get(FixedVectorType::get(
             EltTy, isColumnMajor() ? NumRows : NumColumns)));
     }
+    MatrixTy(ConstantData *Constant, const ShapeInfo &SI)
+        : IsColumnMajor(SI.IsColumnMajor) {
+      Type *EltTy = cast<VectorType>(Constant->getType())->getElementType();
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fhahn wrote:

Would that also help in other places where we have constant operands? If so, could be split off as well?

https://github.com/llvm/llvm-project/pull/141681