[OpenACC] Adjust rules of 'routine' required clauses (llvm#170667)

The interaction between various clauses on 'routine' was not implemented
QUITE right, as I discovered when looking into the implementation of the
ACC dialect. This patch fixes it up so that there can only be 1 of the
special clauses per device_type VALUE (including nvidia ==
    acc_device_nvidia).

This patch also does a refactor/unification of this with the rules of
other clauses, as we now know they are effectively the same.

Author: erichkeane

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -13537,21 +13537,19 @@ def err_acc_clause_after_device_type
 def err_acc_clause_cannot_combine
     : Error<"OpenACC clause '%0' may not appear on the same construct as a "
             "'%1' clause on a '%2' construct">;
-def err_acc_clause_routine_cannot_combine_before_device_type
-    : Error<"OpenACC clause '%0' after 'device_type' clause on a 'routine' "
-              "conflicts with the '%1' clause before the first 'device_type'">;
-def err_acc_clause_routine_cannot_combine_same_device_type
-    : Error<"OpenACC clause '%0' on a 'routine' directive conflicts with the "
-            "'%1' clause applying to the same 'device_type'">;
+def err_acc_clause_cannot_combine_before_device_type
+    : Error<
+          "OpenACC clause '%1' after 'device_type' clause on a '%0' construct "
+          "conflicts with the '%2' clause before the first 'device_type'">;
+def err_acc_clause_cannot_combine_same_device_type
+    : Error<"OpenACC clause '%1' cannot combine with previous '%2' clause"
+            "%select{| in the same 'device_type' region}3 on a '%0' directive">;
+def err_acc_clause_conflicts_prev_dev_type
+    : Error<"OpenACC '%0' clause applies to 'device_type' '%1', which "
+            "conflicts with previous '%2' clause">;
 def err_acc_clause_routine_one_of_in_region
     : Error<"OpenACC 'routine' construct must have at least one 'gang', 'seq', "
             "'vector', or 'worker' clause that applies to each 'device_type'">;
-def err_acc_clause_since_last_device_type
-    : Error<"OpenACC '%0' clause cannot appear more than once%select{| in a "
-            "'device_type' region}2 on a '%1' directive">;
-def err_acc_clause_conflicts_prev_dev_type
-    : Error<"OpenACC '%0' clause applies to 'device_type' '%1', which "
-            "conflicts with previous '%0' clause">;
 
 def err_acc_reduction_num_gangs_conflict
     : Error<"OpenACC '%1' clause %select{|with more than 1 argument }0may not "

clang/lib/Sema/SemaOpenACCClause.cpp

@@ -1315,16 +1315,16 @@ void Gang() {
 
 }
 
-  // expected-error@+4{{OpenACC clause 'seq' may not appear on the same construct as a 'worker' clause on a 'routine' construct}}
+  // expected-error@+4{{OpenACC clause 'seq' cannot combine with previous 'worker' clause on a 'routine' directive}}
   // expected-note@+3{{previous 'worker' clause is here}}
-  // expected-error@+2{{OpenACC clause 'vector' may not appear on the same construct as a 'worker' clause on a 'routine' construct}}
+  // expected-error@+2{{OpenACC clause 'vector' cannot combine with previous 'worker' clause on a 'routine' directive}}
   // expected-note@+1{{previous 'worker' clause is here}}
 #pragma acc routine worker, vector, seq, nohost
 void bar();
 
-  // expected-error@+4{{OpenACC clause 'seq' may not appear on the same construct as a 'worker' clause on a 'routine' construct}}
+  // expected-error@+4{{OpenACC clause 'seq' cannot combine with previous 'worker' clause on a 'routine' directive}}
   // expected-note@+3{{previous 'worker' clause is here}}
-  // expected-error@+2{{OpenACC clause 'vector' may not appear on the same construct as a 'worker' clause on a 'routine' construct}}
+  // expected-error@+2{{OpenACC clause 'vector' cannot combine with previous 'worker' clause on a 'routine' directive}}
   // expected-note@+1{{previous 'worker' clause is here}}
 #pragma acc routine(bar) worker, vector, seq, nohost
 

clang/test/ParserOpenACC/parse-clauses.c

@@ -13,23 +13,23 @@ void Test() {
 #pragma acc parallel loop num_gangs(1)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+2{{OpenACC 'num_gangs' clause cannot appear more than once on a 'kernels loop' directive}}
+  // expected-error@+2{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause on a 'kernels loop' directive}}
   // expected-note@+1{{previous 'num_gangs' clause is here}}
 #pragma acc kernels loop num_gangs(1) num_gangs(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+2{{OpenACC 'num_gangs' clause cannot appear more than once on a 'parallel loop' directive}}
+  // expected-error@+2{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause on a 'parallel loop' directive}}
   // expected-note@+1{{previous 'num_gangs' clause is here}}
 #pragma acc parallel loop num_gangs(1) num_gangs(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+3{{OpenACC 'num_gangs' clause cannot appear more than once in a 'device_type' region on a 'kernels loop' directive}}
+  // expected-error@+3{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause in the same 'device_type' region on a 'kernels loop' directive}}
   // expected-note@+2{{previous 'num_gangs' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels loop num_gangs(1) device_type(*) num_gangs(1) num_gangs(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+3{{OpenACC 'num_gangs' clause cannot appear more than once in a 'device_type' region on a 'parallel loop' directive}}
+  // expected-error@+3{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause in the same 'device_type' region on a 'parallel loop' directive}}
   // expected-note@+2{{previous 'num_gangs' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel loop device_type(*) num_gangs(1) num_gangs(2)

clang/test/SemaOpenACC/combined-construct-num_gangs-clause.c

@@ -13,23 +13,23 @@ void Test() {
 #pragma acc parallel loop num_workers(1)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+2{{OpenACC 'num_workers' clause cannot appear more than once on a 'kernels loop' directive}}
+  // expected-error@+2{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause on a 'kernels loop' directive}}
   // expected-note@+1{{previous 'num_workers' clause is here}}
 #pragma acc kernels loop num_workers(1) num_workers(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+2{{OpenACC 'num_workers' clause cannot appear more than once on a 'parallel loop' directive}}
+  // expected-error@+2{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause on a 'parallel loop' directive}}
   // expected-note@+1{{previous 'num_workers' clause is here}}
 #pragma acc parallel loop num_workers(1) num_workers(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+3{{OpenACC 'num_workers' clause cannot appear more than once in a 'device_type' region on a 'kernels loop' directive}}
+  // expected-error@+3{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause in the same 'device_type' region on a 'kernels loop' directive}}
   // expected-note@+2{{previous 'num_workers' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels loop num_workers(1) device_type(*) num_workers(1) num_workers(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+3{{OpenACC 'num_workers' clause cannot appear more than once in a 'device_type' region on a 'parallel loop' directive}}
+  // expected-error@+3{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause in the same 'device_type' region on a 'parallel loop' directive}}
   // expected-note@+2{{previous 'num_workers' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel loop device_type(*) num_workers(1) num_workers(2)

clang/test/SemaOpenACC/combined-construct-num_workers-clause.c

@@ -13,23 +13,23 @@ void Test() {
 #pragma acc parallel loop vector_length(1)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+2{{OpenACC 'vector_length' clause cannot appear more than once on a 'kernels loop' directive}}
+  // expected-error@+2{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause on a 'kernels loop' directive}}
   // expected-note@+1{{previous 'vector_length' clause is here}}
 #pragma acc kernels loop vector_length(1) vector_length(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+2{{OpenACC 'vector_length' clause cannot appear more than once on a 'parallel loop' directive}}
+  // expected-error@+2{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause on a 'parallel loop' directive}}
   // expected-note@+1{{previous 'vector_length' clause is here}}
 #pragma acc parallel loop vector_length(1) vector_length(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+3{{OpenACC 'vector_length' clause cannot appear more than once in a 'device_type' region on a 'kernels loop' directive}}
+  // expected-error@+3{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause in the same 'device_type' region on a 'kernels loop' directive}}
   // expected-note@+2{{previous 'vector_length' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels loop vector_length(1) device_type(*) vector_length(1) vector_length(2)
   for(int i = 5; i < 10;++i);
 
-  // expected-error@+3{{OpenACC 'vector_length' clause cannot appear more than once in a 'device_type' region on a 'parallel loop' directive}}
+  // expected-error@+3{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause in the same 'device_type' region on a 'parallel loop' directive}}
   // expected-note@+2{{previous 'vector_length' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel loop device_type(*) vector_length(1) vector_length(2)

clang/test/SemaOpenACC/combined-construct-vector_length-clause.c

@@ -20,43 +20,43 @@ void Test() {
 #pragma acc serial async(1, 2)
   while(1);
 
-  // expected-error@+2{{OpenACC 'async' clause cannot appear more than once on a 'kernels' directive}}
+  // expected-error@+2{{OpenACC clause 'async' cannot combine with previous 'async' clause on a 'kernels' directive}}
   // expected-note@+1{{previous 'async' clause is here}}
 #pragma acc kernels async async
   while(1);
 
-  // expected-error@+2{{OpenACC 'async' clause cannot appear more than once on a 'kernels' directive}}
+  // expected-error@+2{{OpenACC clause 'async' cannot combine with previous 'async' clause on a 'kernels' directive}}
   // expected-note@+1{{previous 'async' clause is here}}
 #pragma acc kernels async(1) async(2)
   while(1);
 
-  // expected-error@+2{{OpenACC 'async' clause cannot appear more than once on a 'parallel' directive}}
+  // expected-error@+2{{OpenACC clause 'async' cannot combine with previous 'async' clause on a 'parallel' directive}}
   // expected-note@+1{{previous 'async' clause is here}}
 #pragma acc parallel async(1) async(2)
   while(1);
 
-  // expected-error@+2{{OpenACC 'async' clause cannot appear more than once on a 'serial' directive}}
+  // expected-error@+2{{OpenACC clause 'async' cannot combine with previous 'async' clause on a 'serial' directive}}
   // expected-note@+1{{previous 'async' clause is here}}
 #pragma acc serial async(1) async(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'async' clause cannot appear more than once in a 'device_type' region on a 'kernels' directive}}
+  // expected-error@+3{{OpenACC clause 'async' cannot combine with previous 'async' clause in the same 'device_type' region on a 'kernels' directive}}
   // expected-note@+2{{previous 'async' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels async(1) device_type(*) async(1) async(2)
   while(1);
-  // expected-error@+3{{OpenACC 'async' clause cannot appear more than once in a 'device_type' region on a 'parallel' directive}}
+  // expected-error@+3{{OpenACC clause 'async' cannot combine with previous 'async' clause in the same 'device_type' region on a 'parallel' directive}}
   // expected-note@+2{{previous 'async' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel async device_type(*) async async
   while(1);
-  // expected-error@+3{{OpenACC 'async' clause cannot appear more than once in a 'device_type' region on a 'serial' directive}}
+  // expected-error@+3{{OpenACC clause 'async' cannot combine with previous 'async' clause in the same 'device_type' region on a 'serial' directive}}
   // expected-note@+2{{previous 'async' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc serial async(1) device_type(*) async async(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'async' clause cannot appear more than once in a 'device_type' region on a 'parallel' directive}}
+  // expected-error@+3{{OpenACC clause 'async' cannot combine with previous 'async' clause in the same 'device_type' region on a 'parallel' directive}}
   // expected-note@+2{{previous 'async' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel device_type(*) async async

clang/test/SemaOpenACC/compute-construct-async-clause.c

@@ -12,23 +12,23 @@ void Test() {
 #pragma acc parallel num_gangs(1)
   while(1);
 
-  // expected-error@+2{{OpenACC 'num_gangs' clause cannot appear more than once on a 'kernels' directive}}
+  // expected-error@+2{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause on a 'kernels' directive}}
   // expected-note@+1{{previous 'num_gangs' clause is here}}
 #pragma acc kernels num_gangs(1) num_gangs(2)
   while(1);
 
-  // expected-error@+2{{OpenACC 'num_gangs' clause cannot appear more than once on a 'parallel' directive}}
+  // expected-error@+2{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause on a 'parallel' directive}}
   // expected-note@+1{{previous 'num_gangs' clause is here}}
 #pragma acc parallel num_gangs(1) num_gangs(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'num_gangs' clause cannot appear more than once in a 'device_type' region on a 'kernels' directive}}
+  // expected-error@+3{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause in the same 'device_type' region on a 'kernels' directive}}
   // expected-note@+2{{previous 'num_gangs' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels num_gangs(1) device_type(*) num_gangs(1) num_gangs(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'num_gangs' clause cannot appear more than once in a 'device_type' region on a 'parallel' directive}}
+  // expected-error@+3{{OpenACC clause 'num_gangs' cannot combine with previous 'num_gangs' clause in the same 'device_type' region on a 'parallel' directive}}
   // expected-note@+2{{previous 'num_gangs' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel device_type(*) num_gangs(1) num_gangs(2)

clang/test/SemaOpenACC/compute-construct-num_gangs-clause.c

@@ -8,23 +8,23 @@ void Test() {
 #pragma acc kernels num_workers(1)
   while(1);
 
-  // expected-error@+2{{OpenACC 'num_workers' clause cannot appear more than once on a 'kernels' directive}}
+  // expected-error@+2{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause on a 'kernels' directive}}
   // expected-note@+1{{previous 'num_workers' clause is here}}
 #pragma acc kernels num_workers(1) num_workers(2)
   while(1);
 
-  // expected-error@+2{{OpenACC 'num_workers' clause cannot appear more than once on a 'parallel' directive}}
+  // expected-error@+2{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause on a 'parallel' directive}}
   // expected-note@+1{{previous 'num_workers' clause is here}}
 #pragma acc parallel num_workers(1) num_workers(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'num_workers' clause cannot appear more than once in a 'device_type' region on a 'kernels' directive}}
+  // expected-error@+3{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause in the same 'device_type' region on a 'kernels' directive}}
   // expected-note@+2{{previous 'num_workers' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels num_workers(1) device_type(*) num_workers(1) num_workers(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'num_workers' clause cannot appear more than once in a 'device_type' region on a 'parallel' directive}}
+  // expected-error@+3{{OpenACC clause 'num_workers' cannot combine with previous 'num_workers' clause in the same 'device_type' region on a 'parallel' directive}}
   // expected-note@+2{{previous 'num_workers' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel device_type(*) num_workers(1) num_workers(2)

clang/test/SemaOpenACC/compute-construct-num_workers-clause.c

@@ -8,23 +8,23 @@ void Test() {
 #pragma acc kernels vector_length(1)
   while(1);
 
-  // expected-error@+2{{OpenACC 'vector_length' clause cannot appear more than once on a 'kernels' directive}}
+  // expected-error@+2{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause on a 'kernels' directive}}
   // expected-note@+1{{previous 'vector_length' clause is here}}
 #pragma acc kernels vector_length(1) vector_length(2)
   while(1);
 
-  // expected-error@+2{{OpenACC 'vector_length' clause cannot appear more than once on a 'parallel' directive}}
+  // expected-error@+2{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause on a 'parallel' directive}}
   // expected-note@+1{{previous 'vector_length' clause is here}}
 #pragma acc parallel vector_length(1) vector_length(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'vector_length' clause cannot appear more than once in a 'device_type' region on a 'kernels' directive}}
+  // expected-error@+3{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause in the same 'device_type' region on a 'kernels' directive}}
   // expected-note@+2{{previous 'vector_length' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc kernels vector_length(1) device_type(*) vector_length(1) vector_length(2)
   while(1);
 
-  // expected-error@+3{{OpenACC 'vector_length' clause cannot appear more than once in a 'device_type' region on a 'parallel' directive}}
+  // expected-error@+3{{OpenACC clause 'vector_length' cannot combine with previous 'vector_length' clause in the same 'device_type' region on a 'parallel' directive}}
   // expected-note@+2{{previous 'vector_length' clause is here}}
   // expected-note@+1{{active 'device_type' clause here}}
 #pragma acc parallel device_type(*) vector_length(1) vector_length(2)