[Mlir-commits] [mlir] [mlir][bufferization] Fix promote-buffers-to-stack crash caused by nested memref (PR #127441)

[Matthias Springer]

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@@ -89,6 +89,11 @@ static bool defaultIsSmallAlloc(Value alloc, unsigned maximumSizeInBytes,
   auto type = dyn_cast<ShapedType>(alloc.getType());
   if (!type || !alloc.getDefiningOp<memref::AllocOp>())
     return false;
+  auto elementType = type.getElementType();
+  // Not support nested memref type.
+  if (isa<MemRefType>(elementType))
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matthias-springer wrote:

This will still crash on `UnrankedMemRefType` and certain types that implement `MemRefElementTypeInterface`. I think the right way to fix this is to add a helper function `DataLayout::hasKnownTypeSize(Type)`. Internally, there could be function that returns `std::optional<TypeSize>`, which is called by both `getTypeSizeInBits` and `hasKnownTypeSize`.

https://github.com/llvm/llvm-project/pull/127441