fix(t2u): preserve descriptor base displacement

Compose the analyzed pointer-base displacement with the complete descriptor carrier instead of replacing it during marked addptr parsing. Reject incompatible displacement types while preserving the existing descriptor ownership and structured-axis metadata.

Author: elstainniles

third_party/ascend/lib/TritonToUnstructure/OffsetAnalysis.cpp

@@ -598,9 +598,9 @@ void parseAddPtr(triton::AddPtrOp op, const Location &loc,
       isRebuild || ptrOffsetInfo.isPointerDescriptorOwned();
 
   if (isCompleteOffsetCarrier) {
-    // CFO has already accumulated every displacement relative to the common
-    // base into this operand. Do not parse through its SCF producer or add the
-    // base analysis' synthetic zero offset a second time.
+    // The carrier is complete relative to the descriptor base, but parsing
+    // that base may expose an additional displacement from its scalar source.
+    // Preserve both parts when reconstructing the complete pointer offset.
     auto offsetType = dyn_cast<RankedTensorType>(offsetValue.getType());
     auto offsetElementType =
         offsetType ? dyn_cast<IntegerType>(offsetType.getElementType())
@@ -626,7 +626,17 @@ void parseAddPtr(triton::AddPtrOp op, const Location &loc,
       offsetValue = rewriter.create<arith::ExtSIOp>(op.getLoc(), carrierType,
                                                     offsetValue);
     }
-    ptrOffsetInfo.setOffset(offsetValue);
+    Value baseDisplacement = ptrOffsetInfo.getOffset();
+    if (!baseDisplacement ||
+        baseDisplacement.getType() != offsetValue.getType()) {
+      op.emitOpError(
+          "expected pointer-base displacement compatible with complete "
+          "carrier");
+      return;
+    }
+    Value completeOffset = rewriter.create<arith::AddIOp>(
+        op.getLoc(), baseDisplacement, offsetValue);
+    ptrOffsetInfo.setOffset(completeOffset);
     // setUnstructured() updates only the per-axis classification; it does not
     // clear the independent scalar-like property inherited from a splatted
     // base. A complete offset carrier is intentionally opaque here, so there