Handle cleanup of omp allocated variables (OpenMP 5.0).

Currently we are only handling omp allocate directive that is associated
with an allocate statement.  This statement results in malloc and free calls.
The malloc calls are easy to get to as they are in the same block as allocate
directive.  But the free calls come in a separate cleanup block.  To help any
later passes finding them, an allocate directive is generated in the
cleanup block with kind=free. The normal allocate directive is given
kind=allocate.

Backport of a patch posted at
https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588370.html

gcc/fortran/ChangeLog:

	* gfortran.h (struct access_ref): Declare new members
	omp_allocated and omp_allocated_end.
	* openmp.c (gfc_match_omp_allocate): Set new_st.resolved_sym to
	NULL.
	(prepare_omp_allocated_var_list_for_cleanup): New function.
	(gfc_resolve_omp_allocate): Call it.
	* trans-decl.c (gfc_trans_deferred_vars): Process omp_allocated.
	* trans-openmp.c (gfc_trans_omp_allocate): Set kind for the stmt
	generated for allocate directive.

gcc/ChangeLog:

	* tree-core.h (struct tree_base): Add comments.
	* tree-pretty-print.c (dump_generic_node): Handle allocate directive
	kind.
	* tree.h (OMP_ALLOCATE_KIND_ALLOCATE): New define.
	(OMP_ALLOCATE_KIND_FREE): Likewise.

gcc/testsuite/ChangeLog:

	* gfortran.dg/gomp/allocate-6.f90: Test kind of allocate directive.

11 files changed, 106 insertions, 1 deletions

diff --git a/gcc/ChangeLog.omp b/gcc/ChangeLog.omp
index ffd4881..f5d59fb 100644
--- a/gcc/ChangeLog.omp
+++ b/gcc/ChangeLog.omp
@@ -1,6 +1,17 @@
 2022-03-09  Abid Qadeer  <abidh@codesourcery.com>
 
 	Backport of a patch posted at
+	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588370.html
+
+	* tree-core.h (struct tree_base): Add comments.
+	* tree-pretty-print.c (dump_generic_node): Handle allocate directive
+	kind.
+	* tree.h (OMP_ALLOCATE_KIND_ALLOCATE): New define.
+	(OMP_ALLOCATE_KIND_FREE): Likewise.
+
+2022-03-09  Abid Qadeer  <abidh@codesourcery.com>
+
+	Backport of a patch posted at
 	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588369.html
 
 	* tree-pretty-print.c (dump_omp_clause): Handle OMP_CLAUSE_ALLOCATOR.
diff --git a/gcc/fortran/ChangeLog.omp b/gcc/fortran/ChangeLog.omp
index df3d17f..f1c0257 100644
--- a/gcc/fortran/ChangeLog.omp
+++ b/gcc/fortran/ChangeLog.omp
@@ -1,6 +1,21 @@
 2022-03-09  Abid Qadeer  <abidh@codesourcery.com>
 
 	Backport of a patch posted at
+	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588370.html
+
+	* gfortran.h (struct access_ref): Declare new members
+	omp_allocated and omp_allocated_end.
+	* openmp.c (gfc_match_omp_allocate): Set new_st.resolved_sym to
+	NULL.
+	(prepare_omp_allocated_var_list_for_cleanup): New function.
+	(gfc_resolve_omp_allocate): Call it.
+	* trans-decl.c (gfc_trans_deferred_vars): Process omp_allocated.
+	* trans-openmp.c (gfc_trans_omp_allocate): Set kind for the stmt
+	generated for allocate directive.
+
+2022-03-09  Abid Qadeer  <abidh@codesourcery.com>
+
+	Backport of a patch posted at
 	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588369.html
 
 	* trans-openmp.c (gfc_trans_omp_clauses): Handle OMP_LIST_ALLOCATOR.
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index b4f24c2..2de4507 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -1831,6 +1831,7 @@ typedef struct gfc_symbol
   gfc_array_spec *as;
   struct gfc_symbol *result;	/* function result symbol */
   gfc_component *components;	/* Derived type components */
+  gfc_omp_namelist *omp_allocated, *omp_allocated_end;
 
   /* Defined only for Cray pointees; points to their pointer.  */
   struct gfc_symbol *cp_pointer;
diff --git a/gcc/fortran/openmp.c b/gcc/fortran/openmp.c
index c364fe2..7be015f 100644
--- a/gcc/fortran/openmp.c
+++ b/gcc/fortran/openmp.c
@@ -6030,6 +6030,7 @@ gfc_match_omp_allocate (void)
 
   new_st.op = EXEC_OMP_ALLOCATE;
   new_st.ext.omp_clauses = c;
+  new_st.resolved_sym = NULL;
   gfc_free_expr (allocator);
   return MATCH_YES;
 }
@@ -9383,6 +9384,34 @@ gfc_resolve_oacc_routines (gfc_namespace *ns)
 }
 
 static void
+prepare_omp_allocated_var_list_for_cleanup (gfc_omp_namelist *cn, locus loc)
+{
+  gfc_symbol *proc = cn->sym->ns->proc_name;
+  gfc_omp_namelist *p, *n;
+
+  for (n = cn; n; n = n->next)
+    {
+      if (n->sym->attr.allocatable && !n->sym->attr.save
+	  && !n->sym->attr.result && !proc->attr.is_main_program)
+	{
+	  p = gfc_get_omp_namelist ();
+	  p->sym = n->sym;
+	  p->expr = gfc_copy_expr (n->expr);
+	  p->where = loc;
+	  p->next = NULL;
+	  if (proc->omp_allocated == NULL)
+	    proc->omp_allocated_end = proc->omp_allocated = p;
+	  else
+	    {
+	      proc->omp_allocated_end->next = p;
+	      proc->omp_allocated_end = p;
+	    }
+
+	}
+    }
+}
+
+static void
 check_allocate_directive_restrictions (gfc_symbol *sym, gfc_expr *omp_al,
 				       gfc_namespace *ns, locus loc)
 {
@@ -9512,6 +9541,7 @@ gfc_resolve_omp_allocate (gfc_code *code, gfc_namespace *ns)
 						 code->loc);
 	}
     }
+  prepare_omp_allocated_var_list_for_cleanup (cn, code->loc);
 }
 
 
diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index 096de6e..6ef2c9a 100644
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -4609,6 +4609,26 @@ gfc_trans_deferred_vars (gfc_symbol * proc_sym, gfc_wrapped_block * block)
 	  }
     }
 
+  /* Generate a dummy allocate pragma with free kind so that cleanup
+     of those variables which were allocated using the allocate statement
+     associated with an allocate clause happens correctly.  */
+
+  if (proc_sym->omp_allocated)
+    {
+      gfc_clear_new_st ();
+      new_st.op = EXEC_OMP_ALLOCATE;
+      gfc_omp_clauses *c = gfc_get_omp_clauses ();
+      c->lists[OMP_LIST_ALLOCATOR] = proc_sym->omp_allocated;
+      new_st.ext.omp_clauses = c;
+      /* This is just a hacky way to convey to handler that we are
+	 dealing with cleanup here.  Saves us from using another field
+	 for it.  */
+      new_st.resolved_sym = proc_sym->omp_allocated->sym;
+      gfc_add_init_cleanup (block, NULL,
+			    gfc_trans_omp_directive (&new_st));
+      gfc_free_omp_clauses (c);
+      proc_sym->omp_allocated = NULL;
+    }
 
   /* Initialize the INTENT(OUT) derived type dummy arguments.  This
      should be done here so that the offsets and lbounds of arrays
diff --git a/gcc/fortran/trans-openmp.c b/gcc/fortran/trans-openmp.c
index 36787c2..146aa74 100644
--- a/gcc/fortran/trans-openmp.c
+++ b/gcc/fortran/trans-openmp.c
@@ -6410,6 +6410,12 @@ gfc_trans_omp_allocate (gfc_code *code)
   OMP_ALLOCATE_CLAUSES (stmt) = gfc_trans_omp_clauses (&block, clauses,
 						       code->loc, false,
 						       true);
+  if (code->next == NULL && code->block == NULL
+      && code->resolved_sym != NULL)
+    OMP_ALLOCATE_KIND_FREE (stmt) = 1;
+  else
+    OMP_ALLOCATE_KIND_ALLOCATE (stmt) = 1;
+
   gfc_add_expr_to_block (&block, stmt);
   gfc_merge_block_scope (&block);
   return gfc_finish_block (&block);
diff --git a/gcc/testsuite/ChangeLog.omp b/gcc/testsuite/ChangeLog.omp
index ae8c018..3894b61 100644
--- a/gcc/testsuite/ChangeLog.omp
+++ b/gcc/testsuite/ChangeLog.omp
@@ -1,6 +1,13 @@
 2022-03-09  Abid Qadeer  <abidh@codesourcery.com>
 
 	Backport of a patch posted at
+	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588370.html
+
+	* gfortran.dg/gomp/allocate-6.f90: Test kind of allocate directive.
+
+2022-03-09  Abid Qadeer  <abidh@codesourcery.com>
+
+	Backport of a patch posted at
 	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588369.html
 
 	* gfortran.dg/gomp/allocate-6.f90: New test.
diff --git a/gcc/testsuite/gfortran.dg/gomp/allocate-6.f90 b/gcc/testsuite/gfortran.dg/gomp/allocate-6.f90
index 2de2b52..0eb3517 100644
--- a/gcc/testsuite/gfortran.dg/gomp/allocate-6.f90
+++ b/gcc/testsuite/gfortran.dg/gomp/allocate-6.f90
@@ -69,4 +69,5 @@ end type
   allocate(pii, parr(5))
 end subroutine
 
-! { dg-final { scan-tree-dump-times "#pragma omp allocate" 6 "original" } }
+! { dg-final { scan-tree-dump-times "#pragma omp allocate \\(kind=allocate\\)" 6 "original" } }
+! { dg-final { scan-tree-dump "#pragma omp allocate \\(kind=free\\)" "original" } }
diff --git a/gcc/tree-core.h b/gcc/tree-core.h
index e2c641f..7cb9c51 100644
--- a/gcc/tree-core.h
+++ b/gcc/tree-core.h
@@ -1230,6 +1230,9 @@ struct GTY(()) tree_base {
        EXPR_LOCATION_WRAPPER_P in
 	   NON_LVALUE_EXPR, VIEW_CONVERT_EXPR
 
+       OMP_ALLOCATE_KIND_ALLOCATE in
+	   OMP_ALLOCATE
+
    private_flag:
 
        TREE_PRIVATE in
@@ -1256,6 +1259,9 @@ struct GTY(()) tree_base {
        ENUM_IS_OPAQUE in
 	   ENUMERAL_TYPE
 
+       OMP_ALLOCATE_KIND_FREE in
+	   OMP_ALLOCATE
+
    protected_flag:
 
        TREE_PROTECTED in
diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index dfc7624..fd336d3 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -3538,6 +3538,10 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
 
     case OMP_ALLOCATE:
       pp_string (pp, "#pragma omp allocate ");
+      if (OMP_ALLOCATE_KIND_ALLOCATE (node))
+	pp_string (pp, "(kind=allocate) ");
+      else if (OMP_ALLOCATE_KIND_FREE (node))
+	pp_string (pp, "(kind=free) ");
       dump_omp_clauses (pp, OMP_ALLOCATE_CLAUSES (node), spc, flags);
       break;
 
diff --git a/gcc/tree.h b/gcc/tree.h
index 57fa201..4145206 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1400,6 +1400,10 @@ class auto_suppress_location_wrappers
   TREE_OPERAND (OACC_UPDATE_CHECK (NODE), 0)
 
 #define OMP_ALLOCATE_CLAUSES(NODE) TREE_OPERAND (OMP_ALLOCATE_CHECK (NODE), 0)
+#define OMP_ALLOCATE_KIND_ALLOCATE(NODE) \
+  (OMP_ALLOCATE_CHECK (NODE)->base.public_flag)
+#define OMP_ALLOCATE_KIND_FREE(NODE) \
+  (OMP_ALLOCATE_CHECK (NODE)->base.private_flag)
 
 #define OMP_PARALLEL_BODY(NODE)    TREE_OPERAND (OMP_PARALLEL_CHECK (NODE), 0)
 #define OMP_PARALLEL_CLAUSES(NODE) TREE_OPERAND (OMP_PARALLEL_CHECK (NODE), 1)