[Mlir-commits] [mlir] [mlir][EmitC] Expand the MemRefToEmitC pass - Lowering `CopyOp` (PR #151206)

[Gil Rapaport]

================
@@ -97,6 +99,49 @@ Type convertMemRefType(MemRefType opTy, const TypeConverter *typeConverter) {
   return resultTy;
 }
 
+static Value calculateMemrefTotalSizeBytes(Location loc, MemRefType memrefType,
+                                           OpBuilder &builder) {
+  assert(isMemRefTypeLegalForEmitC(memrefType) &&
+         "incompatible memref type for EmitC conversion");
+  emitc::CallOpaqueOp elementSize = builder.create<emitc::CallOpaqueOp>(
+      loc, emitc::SizeTType::get(builder.getContext()),
+      builder.getStringAttr("sizeof"), ValueRange{},
+      ArrayAttr::get(builder.getContext(),
+                     {TypeAttr::get(memrefType.getElementType())}));
+
+  IndexType indexType = builder.getIndexType();
+  int64_t numElements = std::accumulate(memrefType.getShape().begin(),
+                                        memrefType.getShape().end(), int64_t{1},
+                                        std::multiplies<int64_t>());
+  emitc::ConstantOp numElementsValue = builder.create<emitc::ConstantOp>(
+      loc, indexType, builder.getIndexAttr(numElements));
+
+  Type sizeTType = emitc::SizeTType::get(builder.getContext());
+  emitc::MulOp totalSizeBytes = builder.create<emitc::MulOp>(
+      loc, sizeTType, elementSize.getResult(0), numElementsValue);
+
+  return totalSizeBytes.getResult();
+}
+
+static emitc::ApplyOp
+createPointerFromEmitcArray(Location loc, OpBuilder &builder,
+                            TypedValue<emitc::ArrayType> arrayValue) {
+
+  emitc::ConstantOp zeroIndex = builder.create<emitc::ConstantOp>(
+      loc, builder.getIndexType(), builder.getIndexAttr(0));
+
+  int64_t rank = arrayValue.getType().getRank();
+  llvm::SmallVector<mlir::Value> indices(rank, zeroIndex);
+
+  emitc::SubscriptOp subPtr =
+      builder.create<emitc::SubscriptOp>(loc, arrayValue, ValueRange(indices));
+  emitc::ApplyOp ptr = builder.create<emitc::ApplyOp>(
+      loc, emitc::PointerType::get(arrayValue.getType().getElementType()),
+      builder.getStringAttr("&"), subPtr);
----------------
aniragil wrote:

```suggestion
  ArrayType arrayType = arrayValue.getType();
  llvm::SmallVector<mlir::Value> indices(arrayType.getRank(), zeroIndex);

  emitc::SubscriptOp subPtr =
      builder.create<emitc::SubscriptOp>(loc, arrayValue, ValueRange(indices));
  emitc::ApplyOp ptr = builder.create<emitc::ApplyOp>(
      loc, emitc::PointerType::get(arrayType.getElementType()),
      builder.getStringAttr("&"), subPtr);
```

https://github.com/llvm/llvm-project/pull/151206