[OPENMP50]Perform data mapping analysis only for explicitly mapped data.

[ABataev]

Summary

According to OpenMP 5.0, the restrictions for mapping of overlapped data
apply only for explicitly mapped data, there is no restriction for
implicitly mapped data just like in OpenMP 4.5.

[ABataev]

Rebase

[ABataev]

Rebase

[jdoerfert]

LGTM

clang/lib/Sema/SemaOpenMP.cpp

for (Expr *RE : MVLI.VarList) {
     // Check conflicts with other map clause expressions. We check the conflicts
     // with the current construct separately from the enclosing data
     // environment, because the restrictions are different. We only have to
     // check conflicts across regions for the map clauses.
     if (checkMapConflicts(SemaRef, DSAS, CurDeclaration, SimpleExpr,
                           /*CurrentRegionOnly=*/true, CurComponents, CKind))
       break;
     if (CKind == OMPC_map &&
+        (SemaRef.getLangOpts().OpenMP <= 45 || StartLoc.isValid()) &&
         checkMapConflicts(SemaRef, DSAS, CurDeclaration, SimpleExpr,
                           /*CurrentRegionOnly=*/false, CurComponents, CKind))
       break;
 
     // OpenMP 4.5 [2.10.5, target update Construct]
     // OpenMP 4.5 [2.15.5.1, map Clause, Restrictions, C++, p.1]
     //  If the type of a list item is a reference to a type T then the type will
     //  be considered to be T for all purposes of this clause.

clang/test/OpenMP/target_map_messages.cpp

int main(int argc, char **argv) {
   int *k = &j;
   S6<int> m;
   int x;
   int y;
   int to, tofrom, always, close;
   const int (&l)[5] = da;
   SC1 s;
   SC1 *p;
+  int Arr[10];
 #pragma omp target data map // expected-error {{expected '(' after 'map'}} le45-error {{expected at least one 'map' or 'use_device_ptr' clause for '#pragma omp target data'}} le50-error {{expected at least one 'map', 'use_device_ptr', or 'use_device_addr' clause for '#pragma omp target data'}}
 #pragma omp target data map( // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}}
 #pragma omp target data map() // expected-error {{expected expression}}
 #pragma omp target data map(alloc) // expected-error {{use of undeclared identifier 'alloc'}}
 #pragma omp target data map(to argc // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected ',' or ')' in 'map' clause}}
 #pragma omp target data map(to:) // expected-error {{expected expression}}
 #pragma omp target data map(from: argc, // expected-error {{expected expression}} expected-error {{expected ')'}} expected-note {{to match this '('}}
 #pragma omp target data map(x: y) // expected-error {{incorrect map type, expected one of 'to', 'from', 'tofrom', 'alloc', 'release', or 'delete'}}
#pragma omp target map(release: a) // expected-error {{map type 'release' is not allowed for '#pragma omp target'}}
 
   int marr[10][10], iarr[5];
 
 #pragma omp target map(marr[10][0:2:2]) // expected-error {{expected ']'}} expected-note {{to match this '['}}
   {}
 #pragma omp target map(iarr[:2:d]) // expected-error {{expected ']'}} expected-note {{to match this '['}}
   {}
 
+#pragma omp target data map(Arr[0:4]) // le45-note {{used here}}
+  {
+#pragma omp target
+    Arr[0] = 2; // le45-error {{original storage of expression in data environment is shared but data environment do not fully contain mapped expression storage}}
+  }
+
   return tmain<int, 3>(argc)+tmain<from, 4>(argc); // expected-note {{in instantiation of function template specialization 'tmain<int, 3>' requested here}} expected-note {{in instantiation of function template specialization 'tmain<int, 4>' requested here}}
 }
 #endif