[Mlir-commits] [mlir] [mlir][vector]add foldConstantOp fold function and apply it to extractOp and insertOp. (PR #124399)

[Oleksandr Alex Zinenko]

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@@ -1977,6 +1977,48 @@ static Value foldScalarExtractFromFromElements(ExtractOp extractOp) {
   return fromElementsOp.getElements()[flatIndex];
 }
 
+// If the dynamic operands of `extractOp` or `insertOp` is result of
+// `constantOp`, then fold it.
+template <typename T>
+static LogicalResult foldConstantOp(T op, SmallVectorImpl<Value> &operands) {
+  auto staticPosition = op.getStaticPosition().vec();
+  OperandRange dynamicPosition = op.getDynamicPosition();
+
+  // If the dynamic operands is empty, it is returned directly.
+  if (!dynamicPosition.size())
+    return failure();
+  unsigned index = 0;
+
+  // `opChange` is a flog. If it is true, it means to update `op` in place.
+  bool opChange = false;
+  for (unsigned i = 0, e = staticPosition.size(); i < e; ++i) {
+    if (!ShapedType::isDynamic(staticPosition[i]))
+      continue;
+    Value position = dynamicPosition[index++];
+
+    // If it is a block parameter, proceed to the next iteration.
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ftynse wrote:

Generally, there is no need to add comments to explain trivial blocks of code. One can see _what_ code does, what's missing is _why_.

https://github.com/llvm/llvm-project/pull/124399