[clang][OpenMP] Fix error handling of the adjust_args clause (llvm#94696)

Static verifier noticed the current code has logically dead code parsing
the clause where IsComma is assigned. Fix this and improve the error
message received when a bad adjust-op is specified.

This will now be handled like 'map' where a nice diagnostic is given
with the correct values, then parsing continues on the next clause
reducing unhelpful diagnostics.

Author: mikerice1969

clang/include/clang/Basic/DiagnosticParseKinds.td

@@ -1508,6 +1508,8 @@ def err_omp_unexpected_append_op : Error<
   "unexpected operation specified in 'append_args' clause, expected 'interop'">;
 def err_omp_unexpected_execution_modifier : Error<
   "unexpected 'execution' modifier in non-executable context">;
+def err_omp_unknown_adjust_args_op : Error<
+  "incorrect adjust_args type, expected 'need_device_ptr' or 'nothing'">;
 def err_omp_declare_variant_wrong_clause : Error<
   "expected %select{'match'|'match', 'adjust_args', or 'append_args'}0 clause "
   "on 'omp declare variant' directive">;

clang/lib/Parse/ParseOpenMP.cpp

@@ -4785,8 +4785,8 @@ bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
         getLangOpts());
     Data.ExtraModifierLoc = Tok.getLocation();
     if (Data.ExtraModifier == OMPC_ADJUST_ARGS_unknown) {
-      SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
-                StopBeforeMatch);
+      Diag(Tok, diag::err_omp_unknown_adjust_args_op);
+      SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
     } else {
       ConsumeToken();
       if (Tok.is(tok::colon))
@@ -4799,7 +4799,7 @@ bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
   bool IsComma =
       (Kind != OMPC_reduction && Kind != OMPC_task_reduction &&
        Kind != OMPC_in_reduction && Kind != OMPC_depend &&
-       Kind != OMPC_doacross && Kind != OMPC_map) ||
+       Kind != OMPC_doacross && Kind != OMPC_map && Kind != OMPC_adjust_args) ||
       (Kind == OMPC_reduction && !InvalidReductionId) ||
       (Kind == OMPC_map && Data.ExtraModifier != OMPC_MAP_unknown) ||
       (Kind == OMPC_depend && Data.ExtraModifier != OMPC_DEPEND_unknown) ||

clang/test/OpenMP/declare_variant_clauses_messages.cpp

@@ -186,6 +186,16 @@ void vararg_bar2(const char *fmt) { return; }
 // expected-error@+1 {{variant in '#pragma omp declare variant' with type 'void (float *, float *, int *, omp_interop_t)' (aka 'void (float *, float *, int *, void *)') is incompatible with type 'void (float *, float *, int *)'}}
 #pragma omp declare variant(foo_v4) match(construct={dispatch})
 
+// expected-error@+3 {{incorrect adjust_args type, expected 'need_device_ptr' or 'nothing'}}
+#pragma omp declare variant(foo_v1)                        \
+   match(construct={dispatch}, device={arch(arm)})         \
+   adjust_args(badaaop:AAA,BBB)
+
+// expected-error@+3 {{incorrect adjust_args type, expected 'need_device_ptr' or 'nothing'}}
+#pragma omp declare variant(foo_v1)                        \
+   match(construct={dispatch}, device={arch(arm)})         \
+   adjust_args(badaaop AAA,BBB)
+
 #endif // _OPENMP >= 202011
 #if _OPENMP < 202011  // OpenMP 5.0 or lower
 // expected-error@+2 {{expected 'match' clause on 'omp declare variant' directive}}