[Mlir-commits] [mlir] [MLIR][XeGPU] Recover temporary layout from Anchor Layout (PR #191947)

[Jianhui Li]

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@@ -80,30 +82,199 @@ xegpu::dropInstDataOnAttrs(ArrayRef<NamedAttribute> attrs) {
   return out;
 }
 
-// Attach layout attributes to all vector-type operands of operations within
-// the given operation's region. Reports an error if any vector operand lacks
-// a layout attribute.
-bool xegpu::recoverTemporaryLayouts(Operation *rootOp) {
-  auto result = rootOp->walk([&](Operation *op) {
-    for (OpOperand &operand : op->getOpOperands()) {
-      // Layouts are needed for vector type only.
-      if (!isa<VectorType>(operand.get().getType()))
-        continue;
-      // Skip block arguments since they don't have defining ops to attach
-      // layout attributes to.
-      if (isa<BlockArgument>(operand.get()))
-        continue;
-      auto layout = xegpu::getDistributeLayoutAttr(operand.get());
-      if (!layout) {
-        op->emitWarning("Could not find layout attribute for operand ")
-            << operand.getOperandNumber() << " of operation " << op->getName();
+// Prerequisite for Layout Recovery
+// It relies on the following invariant:
+// 1. there is no layout conflict between different uses of the same definition.
+// 2. each definition has a well-defined layout requirement at its use point.
+//     - Every definition must have at least one use that appears after it in
+//     topological order.
+//     - If a definition has no such use (e.g., a loop result or region output),
+//     an explicit convert_layout operation is inserted to create a use.
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Jianhui-Li wrote:

added TODO.

https://github.com/llvm/llvm-project/pull/191947