[flang-commits] [flang] [flang][cuda] Allow object with SHARED attribute as definable (PR #82822)

[Valentin Clement バレンタイン クレメン via flang-commits]

https://github.com/clementval created https://github.com/llvm/llvm-project/pull/82822

A semantic error was raised in device subprogram like: 

```
attributes(global) subroutine devsubr2()
   real, shared :: rs
   rs = 1
end subroutine
```

Object with the SHARED attribute can be can be read or written by all threads in the block.

https://docs.nvidia.com/hpc-sdk/archive/24.1/compilers/cuda-fortran-prog-guide/index.html#cfpg-var-qual-attr-shared

>From afd09ddb4a97337a10a72f663a3400b9fc9ce5b3 Mon Sep 17 00:00:00 2001
From: Valentin Clement <clementval at gmail.com>
Date: Fri, 23 Feb 2024 11:53:09 -0800
Subject: [PATCH] [flang][cuda] Allow objcte with SHARED attribute as definable

---
 flang/lib/Semantics/definable.cpp | 5 +++--
 flang/test/Semantics/cuf03.cuf    | 7 +++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/flang/lib/Semantics/definable.cpp b/flang/lib/Semantics/definable.cpp
index 2c57efbb40cd18..5c3fa905d60725 100644
--- a/flang/lib/Semantics/definable.cpp
+++ b/flang/lib/Semantics/definable.cpp
@@ -160,9 +160,10 @@ static std::optional<parser::Message> WhyNotDefinableBase(parser::CharBlock at,
             "'%s' is a host-associated allocatable and is not definable in a device subprogram"_err_en_US,
             original);
       } else if (*cudaDataAttr != common::CUDADataAttr::Device &&
-          *cudaDataAttr != common::CUDADataAttr::Managed) {
+          *cudaDataAttr != common::CUDADataAttr::Managed &&
+          *cudaDataAttr != common::CUDADataAttr::Shared) {
         return BlameSymbol(at,
-            "'%s' is not device or managed data and is not definable in a device subprogram"_err_en_US,
+            "'%s' is not device or managed or shared data and is not definable in a device subprogram"_err_en_US,
             original);
       }
     } else if (!isOwnedByDeviceCode) {
diff --git a/flang/test/Semantics/cuf03.cuf b/flang/test/Semantics/cuf03.cuf
index bebfdadbdbb16b..1b1a3b44b0eded 100644
--- a/flang/test/Semantics/cuf03.cuf
+++ b/flang/test/Semantics/cuf03.cuf
@@ -56,4 +56,11 @@ module m
     !WARNING: Pointer 'dp' may not be associated in a device subprogram
     real, device, pointer :: dp
   end subroutine
+
+  attributes(global) subroutine devsubr2()
+    real, shared :: rs
+
+    rs = 1 ! ok
+  end subroutine
+
 end module