[Mlir-commits] [mlir] [mlir] canonicalizer: shape_cast(poison) -> poison (PR #133988)

[Diego Caballero]

================
@@ -5611,28 +5612,27 @@ LogicalResult ShapeCastOp::verify() {
 }
 
 OpFoldResult ShapeCastOp::fold(FoldAdaptor adaptor) {
+
   // No-op shape cast.
-  if (getSource().getType() == getResult().getType())
+  if (getSource().getType() == getType())
     return getSource();
 
   // Canceling shape casts.
   if (auto otherOp = getSource().getDefiningOp<ShapeCastOp>()) {
-    if (getResult().getType() == otherOp.getSource().getType())
-      return otherOp.getSource();
 
-    // Only allows valid transitive folding.
-    VectorType srcType = llvm::cast<VectorType>(otherOp.getSource().getType());
-    VectorType resultType = llvm::cast<VectorType>(getResult().getType());
-    if (srcType.getRank() < resultType.getRank()) {
-      if (!isValidShapeCast(srcType.getShape(), resultType.getShape()))
+    // Only allows valid transitive folding (expand/collapse dimensions).
+    VectorType srcType = otherOp.getSource().getType();
+    if (getType() == srcType)
----------------
dcaballe wrote:

I would keep the `resultType` variable since the type is used multiple times and makes the reading easier

https://github.com/llvm/llvm-project/pull/133988