OpenMP/Fortran: extend 'adjust_args' clause, fixes for it and declare variant [PR115271]

On the extension side, it implements OpenMP 6.0's numeric values/ranges for
the adjust_args arguments, including 'omp_num_args'. And it adds parser
support for need_device_addr. It also implements the post-OpenMP-6.0
clarification of OpenMP spec Issue #4443 regarding type(c_ptr) with
dimension being invalid for need_device_ptr.

To be done: Adding full support for need_device_addr (optional, array
descriptor, ...).

On the invalid side, it removed a bogus c_ptr check that went through
all adjust_args without checking for need_device_ptr and the current scope.

And it finally also processes 'declare variant' in an INTERFACE block,
which is part of PR115271, but it does not handle .mod file yet - the
main issue tracked in that PR.

	PR fortran/115271

gcc/fortran/ChangeLog:

	* gfortran.h (gfc_omp_namelist): Change need_device_ptr to adj_args
	union and add more flags.
	* openmp.cc (gfc_match_omp_declare_variant,
	gfc_resolve_omp_declare): For adjust_args, handle need_device_addr
	and numeric values/ranges besides dummy argument names.
	(resolve_omp_dispatch): Remove bogus a adjust_args check.
	* trans-decl.cc (gfc_handle_omp_declare_variant): New.
	(gfc_generate_module_vars, gfc_generate_function_code): Call it.
	* trans-openmp.cc (gfc_trans_omp_declare_variant): Handle numeric
	values/ranges besides dummy argument names.

gcc/testsuite/ChangeLog:

	* gfortran.dg/gomp/adjust-args-1.f90: Update dg-.* expectations.
	* gfortran.dg/gomp/adjust-args-2.f90: Likewise.
	* gfortran.dg/gomp/adjust-args-2a.f90: Likewise.
	* gfortran.dg/gomp/adjust-args-3.f90: Likewise.
	* gfortran.dg/gomp/adjust-args-4.f90: Remove array from c_ptr.
	* gfortran.dg/gomp/adjust-args-5.f90: Likewise.
	* gfortran.dg/gomp/adjust-args-11.f90: Likewise. Add check that
	INTERFACE is now handled in subroutines and in modules.
	* gfortran.dg/gomp/adjust-args-13.f90: New test.
	* gfortran.dg/gomp/adjust-args-14.f90: New test.
	* gfortran.dg/gomp/adjust-args-15.f90: New test.
	* gfortran.dg/gomp/declare-variant-21.f90: New test.

1 files changed, 23 insertions, 0 deletions

diff --git a/gcc/fortran/trans-decl.cc b/gcc/fortran/trans-decl.cc
index 0acf0e9..ebb63a4 100644
--- a/gcc/fortran/trans-decl.cc
+++ b/gcc/fortran/trans-decl.cc
@@ -6131,6 +6131,19 @@ create_module_nml_decl (gfc_symbol *sym)
     }
 }
 
+static void
+gfc_handle_omp_declare_variant (gfc_symbol * sym)
+{
+  if (sym->attr.external
+      && sym->formal_ns
+      && sym->formal_ns->omp_declare_variant)
+    {
+      gfc_namespace *ns = gfc_current_ns;
+      gfc_current_ns = sym->ns;
+      gfc_get_symbol_decl (sym);
+      gfc_current_ns = ns;
+    }
+}
 
 /* Generate all the required code for module variables.  */
 
@@ -6155,6 +6168,11 @@ gfc_generate_module_vars (gfc_namespace * ns)
   if (flag_coarray == GFC_FCOARRAY_LIB && has_coarray_vars_or_accessors)
     generate_coarray_init (ns);
 
+  /* For OpenMP, ensure that declare variant in INTERFACE is is processed
+     especially as some late diagnostic is only done on tree level.  */
+  if (flag_openmp)
+    gfc_traverse_ns (ns, gfc_handle_omp_declare_variant);
+
   cur_module = NULL;
 
   gfc_trans_use_stmts (ns);
@@ -8005,6 +8023,11 @@ gfc_generate_function_code (gfc_namespace * ns)
 	gfc_conv_cfi_to_gfc (&init, &cleanup, tmp, desc, fsym);
       }
 
+  /* For OpenMP, ensure that declare variant in INTERFACE is is processed
+     especially as some late diagnostic is only done on tree level.  */
+  if (flag_openmp)
+    gfc_traverse_ns (ns, gfc_handle_omp_declare_variant);
+
   gfc_generate_contained_functions (ns);
 
   has_coarray_vars_or_accessors = caf_accessor_head != NULL;