[OpenMP] Require trivially copyable type for mapping

A trivially copyable type provides a trivial copy constructor and a trivial
copy assignment operator. This is enough for the runtime to memcpy the data
to the device. Additionally there must be no virtual functions or virtual
base classes and the destructor is guaranteed to be trivial, ie performs
no action.
The runtime does not require trivial default constructors because on alloc
the memory is undefined. Thus, weaken the warning to be only issued if the
mapped type is not trivially copyable.

Differential Revision: https://reviews.llvm.org/D71134

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -9600,7 +9600,7 @@ def err_omp_reduction_vla_unsupported : Error<
 def err_omp_linear_distribute_var_non_loop_iteration : Error<
   "only loop iteration variables are allowed in 'linear' clause in distribute directives">;
 def warn_omp_non_trivial_type_mapped : Warning<
-  "Non-trivial type %0 is mapped, only trivial types are guaranteed to be mapped correctly">,
+  "Type %0 is not trivially copyable and not guaranteed to be mapped correctly">,
   InGroup<OpenMPMapping>;
 def err_omp_requires_clause_redeclaration : Error <
   "Only one %0 clause can appear on a requires directive in a single translation unit">;

clang/lib/Sema/SemaOpenMP.cpp

@@ -14916,7 +14916,7 @@ static bool checkTypeMappable(SourceLocation SL, SourceRange SR, Sema &SemaRef,
     return false;
   }
   if (FullCheck && !SemaRef.CurContext->isDependentContext() &&
-      !QTy.isTrivialType(SemaRef.Context))
+      !QTy.isTriviallyCopyableType(SemaRef.Context))
     SemaRef.Diag(SL, diag::warn_omp_non_trivial_type_mapped) << QTy << SR;
   return true;
 }

clang/test/OpenMP/distribute_firstprivate_messages.cpp

@@ -95,19 +95,19 @@ int main(int argc, char **argv) {
   for (i = 0; i < argc; ++i) foo();
   #pragma omp target
   #pragma omp teams
-  #pragma omp distribute firstprivate (a, b, c, d, f) // expected-error {{firstprivate variable with incomplete type 'S1'}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-warning {{Non-trivial type 'const S3' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-error {{incomplete type 'S1' where a complete type is required}}
+  #pragma omp distribute firstprivate (a, b, c, d, f) // expected-error {{firstprivate variable with incomplete type 'S1'}} expected-warning {{Type 'const S2' is not trivially copyable and not guaranteed to be mapped correctly}} expected-warning {{Type 'const S3' is not trivially copyable and not guaranteed to be mapped correctly}} expected-error {{incomplete type 'S1' where a complete type is required}}
   for (i = 0; i < argc; ++i) foo();
   #pragma omp target
   #pragma omp teams
   #pragma omp distribute firstprivate (argv[1]) // expected-error {{expected variable name}}
   for (i = 0; i < argc; ++i) foo();
   #pragma omp target
   #pragma omp teams
-  #pragma omp distribute firstprivate(ba) // expected-warning {{Non-trivial type 'const S2 [5]' is mapped, only trivial types are guaranteed to be mapped correctly}}
+  #pragma omp distribute firstprivate(ba) // expected-warning {{Type 'const S2 [5]' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i) foo();
   #pragma omp target
   #pragma omp teams
-  #pragma omp distribute firstprivate(ca) // expected-error {{no matching constructor for initialization of 'S3'}} expected-warning {{Non-trivial type 'const S3 [5]' is mapped, only trivial types are guaranteed to be mapped correctly}}
+  #pragma omp distribute firstprivate(ca) // expected-error {{no matching constructor for initialization of 'S3'}} expected-warning {{Type 'const S3 [5]' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i) foo();
   #pragma omp target
   #pragma omp teams

clang/test/OpenMP/distribute_parallel_for_firstprivate_messages.cpp

@@ -119,7 +119,7 @@ int foomain(int argc, char **argv) {
     ++k;
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(a, b) // expected-error {{firstprivate variable with incomplete type 'S1'}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(a, b) // expected-error {{firstprivate variable with incomplete type 'S1'}} expected-warning {{Type 'const S2' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (int k = 0; k < argc; ++k)
     ++k;
 #pragma omp target
@@ -129,7 +129,7 @@ int foomain(int argc, char **argv) {
     ++k;
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(e, g) // expected-error {{calling a private constructor of class 'S4'}} expected-error {{calling a private constructor of class 'S5'}} expected-warning {{Non-trivial type 'S4' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-warning {{Non-trivial type 'S5' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(e, g) // expected-error {{calling a private constructor of class 'S4'}} expected-error {{calling a private constructor of class 'S5'}} expected-warning {{Type 'S4' is not trivially copyable and not guaranteed to be mapped correctly}} expected-warning {{Type 'S5' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (int k = 0; k < argc; ++k)
     ++k;
 #pragma omp target
@@ -241,7 +241,7 @@ int main(int argc, char **argv) {
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(a, b, c, d, f) // expected-error {{firstprivate variable with incomplete type 'S1'}} expected-error {{incomplete type 'S1' where a complete type is required}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-warning {{Non-trivial type 'const S3' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(a, b, c, d, f) // expected-error {{firstprivate variable with incomplete type 'S1'}} expected-error {{incomplete type 'S1' where a complete type is required}} expected-warning {{Type 'const S2' is not trivially copyable and not guaranteed to be mapped correctly}} expected-warning {{Type 'const S3' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
@@ -256,12 +256,12 @@ int main(int argc, char **argv) {
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(ba) // expected-warning {{Non-trivial type 'const S2 [5]' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(ba) // expected-warning {{Type 'const S2 [5]' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(ca) // expected-warning {{Non-trivial type 'const S3 [5]' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(ca) // expected-warning {{Type 'const S3 [5]' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
@@ -292,12 +292,12 @@ int main(int argc, char **argv) {
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(e, g) // expected-error {{calling a private constructor of class 'S4'}} expected-error {{calling a private constructor of class 'S5'}} expected-warning {{Non-trivial type 'S4' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-warning {{Non-trivial type 'S5' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(e, g) // expected-error {{calling a private constructor of class 'S4'}} expected-error {{calling a private constructor of class 'S5'}} expected-warning {{Type 'S4' is not trivially copyable and not guaranteed to be mapped correctly}} expected-warning {{Type 'S5' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(m) // expected-warning {{Non-trivial type 'S3' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(m) // expected-warning {{Type 'S3' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
@@ -329,13 +329,13 @@ int main(int argc, char **argv) {
 // expected-error@+3 {{lastprivate variable cannot be firstprivate}} expected-note@+3 {{defined as lastprivate}}
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(g) firstprivate(g) // expected-warning {{Non-trivial type 'S5' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(g) firstprivate(g) // expected-warning {{Type 'S5' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 // expected-error@+3 {{lastprivate variable cannot be firstprivate}} expected-note@+3 {{defined as lastprivate}}
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(n) firstprivate(n) // expected-error {{calling a private constructor of class 'S6'}} expected-warning {{Non-trivial type 'S6' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(n) firstprivate(n) // expected-error {{calling a private constructor of class 'S6'}} expected-warning {{Type 'S6' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp parallel

clang/test/OpenMP/distribute_parallel_for_lastprivate_messages.cpp

@@ -112,7 +112,7 @@ int foomain(int argc, char **argv) {
     ++k;
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(a, b) // expected-error {{lastprivate variable with incomplete type 'S1'}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(a, b) // expected-error {{lastprivate variable with incomplete type 'S1'}} expected-warning {{Type 'const S2' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (int k = 0; k < argc; ++k)
     ++k;
 #pragma omp target
@@ -122,7 +122,7 @@ int foomain(int argc, char **argv) {
     ++k;
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(e, g) // expected-error 2 {{calling a private constructor of class 'S4'}} expected-warning 2 {{Non-trivial type 'S4' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(e, g) // expected-error 2 {{calling a private constructor of class 'S4'}} expected-warning 2 {{Type 'S4' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (int k = 0; k < argc; ++k)
     ++k;
 #pragma omp target
@@ -221,7 +221,7 @@ int main(int argc, char **argv) {
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(a, b, c, d, f) // expected-error {{lastprivate variable with incomplete type 'S1'}} expected-error 1 {{const-qualified variable without mutable fields cannot be lastprivate}} expected-error 2 {{const-qualified variable cannot be lastprivate}} expected-error {{incomplete type 'S1' where a complete type is required}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-warning {{Non-trivial type 'const S3' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(a, b, c, d, f) // expected-error {{lastprivate variable with incomplete type 'S1'}} expected-error 1 {{const-qualified variable without mutable fields cannot be lastprivate}} expected-error 2 {{const-qualified variable cannot be lastprivate}} expected-error {{incomplete type 'S1' where a complete type is required}} expected-warning {{Type 'const S2' is not trivially copyable and not guaranteed to be mapped correctly}} expected-warning {{Type 'const S3' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
@@ -236,12 +236,12 @@ int main(int argc, char **argv) {
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(ba) // expected-warning {{Non-trivial type 'const S2 [5]' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(ba) // expected-warning {{Type 'const S2 [5]' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(ca) // expected-error {{const-qualified variable without mutable fields cannot be lastprivate}} expected-warning {{Non-trivial type 'const S3 [5]' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(ca) // expected-error {{const-qualified variable without mutable fields cannot be lastprivate}} expected-warning {{Type 'const S3 [5]' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
@@ -272,12 +272,12 @@ int main(int argc, char **argv) {
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(e, g) // expected-error {{calling a private constructor of class 'S4'}} expected-error {{calling a private constructor of class 'S5'}} expected-warning {{Non-trivial type 'S4' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-warning {{Non-trivial type 'S5' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(e, g) // expected-error {{calling a private constructor of class 'S4'}} expected-error {{calling a private constructor of class 'S5'}} expected-warning {{Type 'S4' is not trivially copyable and not guaranteed to be mapped correctly}} expected-warning {{Type 'S5' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(m) // expected-error {{'operator=' is a private member of 'S3'}} expected-warning {{Non-trivial type 'S3' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(m) // expected-error {{'operator=' is a private member of 'S3'}} expected-warning {{Type 'S3' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 #pragma omp target
@@ -318,13 +318,13 @@ int main(int argc, char **argv) {
 // expected-error@+3 {{firstprivate variable cannot be lastprivate}} expected-note@+3 {{defined as firstprivate}}
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for firstprivate(m) lastprivate(m) // expected-warning {{Non-trivial type 'S3' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for firstprivate(m) lastprivate(m) // expected-warning {{Type 'S3' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
 // expected-error@+3 {{lastprivate variable cannot be firstprivate}} expected-note@+3 {{defined as lastprivate}}
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for lastprivate(n) firstprivate(n) // expected-error {{calling a private constructor of class 'S6'}} expected-warning {{Non-trivial type 'S6' is mapped, only trivial types are guaranteed to be mapped correctly}}
+#pragma omp distribute parallel for lastprivate(n) firstprivate(n) // expected-error {{calling a private constructor of class 'S6'}} expected-warning {{Type 'S6' is not trivially copyable and not guaranteed to be mapped correctly}}
   for (i = 0; i < argc; ++i)
     foo();
   static int si;

clang/test/OpenMP/distribute_parallel_for_private_messages.cpp

@@ -50,7 +50,7 @@ class S5 {
 #pragma omp target
 #pragma omp teams
 #pragma omp distribute parallel for private(a) private(this->a) private(s.a) // expected-error {{expected variable name or data member of current class}}
-    for (int k = 0; k < s.a; ++k) // expected-warning {{Non-trivial type 'S5' is mapped, only trivial types are guaranteed to be mapped correctly}}
+    for (int k = 0; k < s.a; ++k) // expected-warning {{Type 'S5' is not trivially copyable and not guaranteed to be mapped correctly}}
       ++s.a;
     return *this;
   }