[PATCH] D16749: [OpenMP] Map clause codegeneration.

[Alexey Bataev via cfe-commits]

ABataev added inline comments.

================
Comment at: lib/CodeGen/CGExpr.cpp:2937-2943
@@ -2936,2 +2936,9 @@
   QualType BaseTy = Base.getType();
+  // If the base is a pointer, we actually need to compute the offset in the
+  // pointee.
+  if (BaseTy->isAnyPointerType()) {
+    auto RBase = EmitLoadOfLValue(Base, E->getExprLoc());
+    Base = MakeNaturalAlignAddrLValue(
+        RBase.getScalarVal(), BaseTy->getAs<PointerType>()->getPointeeType());
+  }
   llvm::Value *Idx = nullptr;
----------------
This must be fixed already, please reabse

================
Comment at: lib/CodeGen/CGOpenMPRuntime.cpp:3915-3946
@@ +3914,34 @@
+    // Reference types are ignored for mapping purposes.
+    if (auto *RefTy = ExprTy->getAs<ReferenceType>())
+      ExprTy = RefTy->getPointeeType().getCanonicalType();
+
+    // Given that an array section is considered a built-in type, we need to
+    // do the calculation based on the length of the section instead of relying
+    // on CGF.getTypeSize(E->getType()).
+    if (const auto *OAE = dyn_cast<OMPArraySectionExpr>(E)) {
+
+      auto BaseTy = OAE->getBase()->getType().getCanonicalType();
+      // Reference types are ignored for mapping purposes.
+      if (auto *RefTy = BaseTy->getAs<ReferenceType>())
+        BaseTy = RefTy->getPointeeType().getCanonicalType();
+
+      // If there is no length associated with the expression, that means we
+      // are using the whole length of the base.
+      if (!OAE->getLength())
+        return CGF.getTypeSize(BaseTy);
+
+      llvm::Value *ElemSize;
+      if (auto *PTy = BaseTy->getAs<PointerType>()) {
+        ElemSize = CGF.getTypeSize(PTy->getPointeeType().getCanonicalType());
+      } else {
+        auto *ATy = cast<ArrayType>(BaseTy.getTypePtr());
+        assert(ATy && "Expecting array type if not a pointer type.");
+        ElemSize = CGF.getTypeSize(ATy->getElementType().getCanonicalType());
+      }
+
+      auto *LengthVal = CGF.EmitScalarExpr(OAE->getLength());
+      LengthVal =
+          CGF.Builder.CreateIntCast(LengthVal, CGF.SizeTy, /*isSigned=*/false);
+      return CGF.Builder.CreateNUWMul(LengthVal, ElemSize);
+    }
+    return CGF.getTypeSize(ExprTy);
----------------
I don't think this is correct. It won't work for 2(and more)-dimensional array sections. Instead calculate size as 'last_item_address-first_item_address+1'.

================
Comment at: lib/CodeGen/CGOpenMPRuntime.cpp:4126-4128
@@ +4125,5 @@
+      if (auto *ME = dyn_cast<MemberExpr>(I->first)) {
+        // The base is the 'this' pointer. The content of the pointer is going
+        // to be the base of the field being mapped.
+        BP = CGF.EmitScalarExpr(ME->getBase());
+      } else {
----------------
In a few days you won't need it at all. All member references are implicitly captured into special declaration and you should not worry about them at all


http://reviews.llvm.org/D16749