[Mlir-commits] [mlir] [mlir][IR] Generalize`DenseElementsAttr` to custom element types (PR #179122)

[Matthias Springer]

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@@ -85,6 +88,125 @@ IntegerType IntegerType::scaleElementBitwidth(unsigned scale) {
   return IntegerType::get(getContext(), scale * getWidth(), getSignedness());
 }
 
+size_t IntegerType::getDenseElementBitSize() const {
+  // Return the actual bit width. Storage alignment is handled separately.
+  // Note: i1 is bit-packed and should be special-cased by the caller.
+  return getWidth();
+}
+
+Attribute IntegerType::convertToAttribute(ArrayRef<char> rawData) const {
+  APInt value = detail::readBits(rawData.data(), /*bitPos=*/0, getWidth());
+  return IntegerAttr::get(*this, value);
+}
+
+LogicalResult
+IntegerType::convertFromAttribute(Attribute attr,
+                                  SmallVectorImpl<char> &result) const {
+  auto intAttr = dyn_cast<IntegerAttr>(attr);
+  if (!intAttr || intAttr.getType() != *this)
+    return failure();
+
+  size_t byteSize = llvm::divideCeil(getDenseElementBitSize(), CHAR_BIT);
+  size_t bitPos = result.size() * CHAR_BIT;
+  result.resize(result.size() + byteSize);
+  detail::writeBits(result.data(), bitPos, intAttr.getValue());
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matthias-springer wrote:

I removed some of the duplication.

https://github.com/llvm/llvm-project/pull/179122