[Mlir-commits] [flang] [mlir] [Flang][MLIR][OpenMP] - Add support for firstprivate when translating omp.target ops from MLIR to LLVMIR (PR #131213)

[Tom Eccles]

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@@ -158,5 +169,50 @@ class MapsForPrivatizedSymbolsPass
       }
     }
   }
+  // As the name suggests, this function examines var to determine if
+  // it has dynamic size. If true, this pass'll have to extract these
+  // bounds from descriptor of var and add the bounds to the resultant
+  // MapInfoOp.
+  bool needsBoundsOps(mlir::Value var) {
+    assert(mlir::isa<omp::PointerLikeType>(var.getType()) &&
+           "needsBoundsOps can deal only with pointer types");
+    mlir::Type t = fir::unwrapRefType(var.getType());
+    // t could be a box, so look inside the box
+    auto innerType = fir::dyn_cast_ptrOrBoxEleTy(t);
+    if (innerType)
+      return fir::hasDynamicSize(innerType);
+    return fir::hasDynamicSize(t);
+  }
+  void genBoundsOps(fir::FirOpBuilder &builder, mlir::Value var,
+                    llvm::SmallVector<mlir::Value> &boundsOps) {
+    if (!fir::isBoxAddress(var.getType()))
+      return;
+
+    unsigned int rank = 0;
+    rank = fir::getBoxRank(fir::unwrapRefType(var.getType()));
+    mlir::Location loc = var.getLoc();
+    mlir::Type idxTy = builder.getIndexType();
+    mlir::Value one = builder.createIntegerConstant(loc, idxTy, 1);
+    mlir::Type boundTy = builder.getType<omp::MapBoundsType>();
+    mlir::Value box = builder.create<fir::LoadOp>(loc, var);
+    for (unsigned int i = 0; i < rank; ++i) {
+      mlir::Value dimNo = builder.createIntegerConstant(loc, idxTy, i);
+      auto dimInfo =
+          builder.create<fir::BoxDimsOp>(loc, idxTy, idxTy, idxTy, box, dimNo);
+      auto normalizedLB = builder.create<mlir::arith::ConstantOp>(
+          loc, idxTy, builder.getIntegerAttr(idxTy, 0));
+      mlir::Value lb = dimInfo.getLowerBound();
+      mlir::Value extent = dimInfo.getExtent();
+      mlir::Value byteStride = dimInfo.getByteStride();
+      mlir::Value ub = builder.create<mlir::arith::SubIOp>(loc, extent, one);
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tblah wrote:

Why do you subtract 1 here?

https://github.com/llvm/llvm-project/pull/131213