[flang-commits] [flang] [Flang][Semantics] Add a semantic check for simd construct (PR #109089)

[via flang-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-flang-openmp

Author: Thirumalai Shaktivel (Thirumalai-Shaktivel)

<details>
<summary>Changes</summary>

Add:
- Missing semantic check for the SAFELEN clause in the SIMD Order construct
- Missing tests

---
Full diff: https://github.com/llvm/llvm-project/pull/109089.diff


4 Files Affected:

- (modified) flang/lib/Semantics/check-omp-structure.cpp (+10) 
- (modified) flang/test/Semantics/OpenMP/clause-validity01.f90 (+6) 
- (modified) flang/test/Semantics/OpenMP/do-collapse.f90 (+7-1) 
- (modified) flang/test/Semantics/OpenMP/loop-association.f90 (+6) 


``````````diff
diff --git a/flang/lib/Semantics/check-omp-structure.cpp b/flang/lib/Semantics/check-omp-structure.cpp
index 643b713b32e29d..eac856f56fe8fd 100644
--- a/flang/lib/Semantics/check-omp-structure.cpp
+++ b/flang/lib/Semantics/check-omp-structure.cpp
@@ -2156,6 +2156,16 @@ void OmpStructureChecker::Leave(const parser::OmpClauseList &) {
         }
       }
     }
+
+    // 2.11.5 Simd construct restriction (OpenMP 5.1)
+    if ( auto *clause{FindClause(llvm::omp::Clause::OMPC_safelen)} ) {
+      if ( FindClause(llvm::omp::Clause::OMPC_order) ) {
+        context_.Say(clause->source,
+          "The `SAFELEN` clause cannot appear in the `SIMD` directive "
+          "with `ORDER(CONCURRENT)` clause"_err_en_US);
+      }
+    }
+
     // Sema checks related to presence of multiple list items within the same
     // clause
     CheckMultListItems();
diff --git a/flang/test/Semantics/OpenMP/clause-validity01.f90 b/flang/test/Semantics/OpenMP/clause-validity01.f90
index 020d63f735596d..9344258b9c1522 100644
--- a/flang/test/Semantics/OpenMP/clause-validity01.f90
+++ b/flang/test/Semantics/OpenMP/clause-validity01.f90
@@ -390,6 +390,12 @@
   enddo
   !$omp end parallel
 
+  !ERROR: The `SAFELEN` clause cannot appear in the `SIMD` directive with `ORDER(CONCURRENT)` clause
+  !$omp simd order(concurrent) safelen(1+2)
+  do i = 1, N
+    a = 3.14
+  enddo
+
 ! 2.11.1 parallel-do-clause -> parallel-clause |
 !                              do-clause
 
diff --git a/flang/test/Semantics/OpenMP/do-collapse.f90 b/flang/test/Semantics/OpenMP/do-collapse.f90
index 4f2512937ace4e..480bd45b79b839 100644
--- a/flang/test/Semantics/OpenMP/do-collapse.f90
+++ b/flang/test/Semantics/OpenMP/do-collapse.f90
@@ -30,5 +30,11 @@ program omp_doCollapse
       do
       end do
     end do
-end program omp_doCollapse
 
+  !ERROR: At most one COLLAPSE clause can appear on the SIMD directive
+  !$omp simd collapse(2) collapse(1)
+  do i = 1, 4
+    j = j + i + 1
+  end do
+  !$omp end simd
+end program omp_doCollapse
diff --git a/flang/test/Semantics/OpenMP/loop-association.f90 b/flang/test/Semantics/OpenMP/loop-association.f90
index d2167663c5ddea..9fac508e6128a7 100644
--- a/flang/test/Semantics/OpenMP/loop-association.f90
+++ b/flang/test/Semantics/OpenMP/loop-association.f90
@@ -131,4 +131,10 @@
   !$omp end parallel do simd
   !ERROR: The END PARALLEL DO SIMD directive must follow the DO loop associated with the loop construct
   !$omp end parallel do simd
+
+  !ERROR: A DO loop must follow the SIMD directive
+  !$omp simd
+    a = i + 1
+  !ERROR: The END SIMD directive must follow the DO loop associated with the loop construct
+  !$omp end simd
 end

``````````

</details>


https://github.com/llvm/llvm-project/pull/109089