Fortran: Fix class transformational intrinsic calls [PR102689]

2024-08-06  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran
	PR fortran/102689
	* trans-array.cc (get_array_ref_dim_for_loop_dim): Use the arg1
	class container carried in ss->info as the seed for a lhs in
	class valued transformational intrinsic calls that are not the
	rhs of an assignment. Otherwise, the lhs variable expression is
	taken from the loop chain. For this latter case, the _vptr and
	_len fields are set.
	(gfc_trans_create_temp_array): Use either the lhs expression
	seeds to build a class variable that will take the returned
	descriptor as its _data field. In the case that the arg1 expr.
	is used, a class typespec must be built with the correct rank
	and the _vptr and _len fields set. The element size is provided
	for the temporary allocation and to set the descriptor span.
	(gfc_array_init_size): When an intrinsic type scalar expr3 is
	used in allocation of a class array, use its element size in
	the descriptor dtype.
	* trans-expr.cc (gfc_conv_class_to_class): Class valued
	transformational intrinsics return the pointer to the array
	descriptor as the _data field of a class temporary. Extract
	directly and return the address of the class temporary.
	(gfc_conv_procedure_call): store the expression for the first
	argument of a class valued transformational intrinsic function
	in the ss info class_container field. Later, use its type  as
	the element type in the call to gfc_trans_create_temp_array.
	(fcncall_realloc_result): Add a dtype argument and use it in
	the descriptor, when available.
	(gfc_trans_arrayfunc_assign): For class lhs, build a dtype with
	the lhs rank and the rhs element size and use it in the call to
	fcncall_realloc_result.

gcc/testsuite/
	PR fortran/102689
	* gfortran.dg/class_transformational_1.f90: New test for class-
	valued reshape.
	* gfortran.dg/class_transformational_2.f90: New test for other
	class_valued transformational intrinsics.

2 files changed, 168 insertions, 35 deletions

diff --git a/gcc/fortran/trans-array.cc b/gcc/fortran/trans-array.cc
index c93a5f1..9fb0b2b 100644
--- a/gcc/fortran/trans-array.cc
+++ b/gcc/fortran/trans-array.cc
@@ -1301,23 +1301,28 @@ get_array_ref_dim_for_loop_dim (gfc_ss *ss, int loop_dim)
    is a class expression.  */
 
 static tree
-get_class_info_from_ss (stmtblock_t * pre, gfc_ss *ss, tree *eltype)
+get_class_info_from_ss (stmtblock_t * pre, gfc_ss *ss, tree *eltype,
+			gfc_ss **fcnss)
 {
+  gfc_ss *loop_ss = ss->loop->ss;
   gfc_ss *lhs_ss;
   gfc_ss *rhs_ss;
+  gfc_ss *fcn_ss = NULL;
   tree tmp;
   tree tmp2;
   tree vptr;
-  tree rhs_class_expr = NULL_TREE;
+  tree class_expr = NULL_TREE;
   tree lhs_class_expr = NULL_TREE;
   bool unlimited_rhs = false;
   bool unlimited_lhs = false;
   bool rhs_function = false;
+  bool unlimited_arg1 = false;
   gfc_symbol *vtab;
+  tree cntnr = NULL_TREE;
 
   /* The second element in the loop chain contains the source for the
-     temporary; ie. the rhs of the assignment.  */
-  rhs_ss = ss->loop->ss->loop_chain;
+     class temporary created in gfc_trans_create_temp_array.  */
+  rhs_ss = loop_ss->loop_chain;
 
   if (rhs_ss != gfc_ss_terminator
       && rhs_ss->info
@@ -1326,28 +1331,58 @@ get_class_info_from_ss (stmtblock_t * pre, gfc_ss *ss, tree *eltype)
       && rhs_ss->info->data.array.descriptor)
     {
       if (rhs_ss->info->expr->expr_type != EXPR_VARIABLE)
-	rhs_class_expr
+	class_expr
 	  = gfc_get_class_from_expr (rhs_ss->info->data.array.descriptor);
       else
-	rhs_class_expr = gfc_get_class_from_gfc_expr (rhs_ss->info->expr);
+	class_expr = gfc_get_class_from_gfc_expr (rhs_ss->info->expr);
       unlimited_rhs = UNLIMITED_POLY (rhs_ss->info->expr);
       if (rhs_ss->info->expr->expr_type == EXPR_FUNCTION)
 	rhs_function = true;
     }
 
+  /* Usually, ss points to the function. When the function call is an actual
+     argument, it is instead rhs_ss because the ss chain is shifted by one.  */
+  *fcnss = fcn_ss = rhs_function ? rhs_ss : ss;
+
+  /* If this is a transformational function with a class result, the info
+     class_container field points to the class container of arg1.  */
+  if (class_expr != NULL_TREE
+      && fcn_ss->info && fcn_ss->info->expr
+      && fcn_ss->info->expr->expr_type == EXPR_FUNCTION
+      && fcn_ss->info->expr->value.function.isym
+      && fcn_ss->info->expr->value.function.isym->transformational)
+    {
+      cntnr = ss->info->class_container;
+      unlimited_arg1
+	   = UNLIMITED_POLY (fcn_ss->info->expr->value.function.actual->expr);
+    }
+
   /* For an assignment the lhs is the next element in the loop chain.
      If we have a class rhs, this had better be a class variable
-     expression!  */
+     expression!  Otherwise, the class container from arg1 can be used
+     to set the vptr and len fields of the result class container.  */
   lhs_ss = rhs_ss->loop_chain;
-  if (lhs_ss != gfc_ss_terminator
-      && lhs_ss->info
-      && lhs_ss->info->expr
+  if (lhs_ss && lhs_ss != gfc_ss_terminator
+      && lhs_ss->info && lhs_ss->info->expr
       && lhs_ss->info->expr->expr_type ==EXPR_VARIABLE
       && lhs_ss->info->expr->ts.type == BT_CLASS)
     {
       tmp = lhs_ss->info->data.array.descriptor;
       unlimited_lhs = UNLIMITED_POLY (rhs_ss->info->expr);
     }
+  else if (cntnr != NULL_TREE)
+    {
+      tmp = gfc_class_vptr_get (class_expr);
+      gfc_add_modify (pre, tmp, fold_convert (TREE_TYPE (tmp),
+					      gfc_class_vptr_get (cntnr)));
+      if (unlimited_rhs)
+	{
+	  tmp = gfc_class_len_get (class_expr);
+	  if (unlimited_arg1)
+	    gfc_add_modify (pre, tmp, gfc_class_len_get (cntnr));
+	}
+      tmp = NULL_TREE;
+    }
   else
     tmp = NULL_TREE;
 
@@ -1355,35 +1390,33 @@ get_class_info_from_ss (stmtblock_t * pre, gfc_ss *ss, tree *eltype)
   if (tmp != NULL_TREE && lhs_ss->loop_chain == gfc_ss_terminator)
     lhs_class_expr = gfc_get_class_from_expr (tmp);
   else
-    return rhs_class_expr;
+    return class_expr;
 
   gcc_assert (GFC_CLASS_TYPE_P (TREE_TYPE (lhs_class_expr)));
 
   /* Set the lhs vptr and, if necessary, the _len field.  */
-  if (rhs_class_expr)
+  if (class_expr)
     {
       /* Both lhs and rhs are class expressions.  */
       tmp = gfc_class_vptr_get (lhs_class_expr);
       gfc_add_modify (pre, tmp,
 		      fold_convert (TREE_TYPE (tmp),
-				    gfc_class_vptr_get (rhs_class_expr)));
+				    gfc_class_vptr_get (class_expr)));
       if (unlimited_lhs)
 	{
+	  gcc_assert (unlimited_rhs);
 	  tmp = gfc_class_len_get (lhs_class_expr);
-	  if (unlimited_rhs)
-	    tmp2 = gfc_class_len_get (rhs_class_expr);
-	  else
-	    tmp2 = build_int_cst (TREE_TYPE (tmp), 0);
+	  tmp2 = gfc_class_len_get (class_expr);
 	  gfc_add_modify (pre, tmp, tmp2);
 	}
 
       if (rhs_function)
 	{
-	  tmp = gfc_class_data_get (rhs_class_expr);
+	  tmp = gfc_class_data_get (class_expr);
 	  gfc_conv_descriptor_offset_set (pre, tmp, gfc_index_zero_node);
 	}
     }
-  else
+  else if (rhs_ss->info->data.array.descriptor)
    {
       /* lhs is class and rhs is intrinsic or derived type.  */
       *eltype = TREE_TYPE (rhs_ss->info->data.array.descriptor);
@@ -1411,7 +1444,7 @@ get_class_info_from_ss (stmtblock_t * pre, gfc_ss *ss, tree *eltype)
 	}
     }
 
-  return rhs_class_expr;
+  return class_expr;
 }
 
 
@@ -1452,6 +1485,7 @@ gfc_trans_create_temp_array (stmtblock_t * pre, stmtblock_t * post, gfc_ss * ss,
   tree or_expr;
   tree elemsize;
   tree class_expr = NULL_TREE;
+  gfc_ss *fcn_ss = NULL;
   int n, dim, tmp_dim;
   int total_dim = 0;
 
@@ -1471,7 +1505,7 @@ gfc_trans_create_temp_array (stmtblock_t * pre, stmtblock_t * post, gfc_ss * ss,
      The descriptor can be obtained from the ss->info and then converted
      to the class object.  */
   if (class_expr == NULL_TREE && GFC_CLASS_TYPE_P (eltype))
-    class_expr = get_class_info_from_ss (pre, ss, &eltype);
+    class_expr = get_class_info_from_ss (pre, ss, &eltype, &fcn_ss);
 
   /* If the dynamic type is not available, use the declared type.  */
   if (eltype && GFC_CLASS_TYPE_P (eltype))
@@ -1571,14 +1605,46 @@ gfc_trans_create_temp_array (stmtblock_t * pre, stmtblock_t * post, gfc_ss * ss,
   gfc_add_expr_to_block (pre, build1 (DECL_EXPR,
 				      arraytype, TYPE_NAME (arraytype)));
 
-  if (class_expr != NULL_TREE)
+  if (class_expr != NULL_TREE
+      || (fcn_ss && fcn_ss->info && fcn_ss->info->class_container))
     {
       tree class_data;
       tree dtype;
+      gfc_expr *expr1 = fcn_ss ? fcn_ss->info->expr : NULL;
 
-      /* Create a class temporary.  */
-      tmp = gfc_create_var (TREE_TYPE (class_expr), "ctmp");
-      gfc_add_modify (pre, tmp, class_expr);
+      /* Create a class temporary for the result using the lhs class object.  */
+      if (class_expr != NULL_TREE)
+	{
+	  tmp = gfc_create_var (TREE_TYPE (class_expr), "ctmp");
+	  gfc_add_modify (pre, tmp, class_expr);
+	}
+      else
+	{
+	  tree vptr;
+	  class_expr = fcn_ss->info->class_container;
+	  gcc_assert (expr1);
+
+	  /* Build a new class container using the arg1 class object. The class
+	     typespec must be rebuilt because the rank might have changed.  */
+	  gfc_typespec ts = CLASS_DATA (expr1)->ts;
+	  symbol_attribute attr = CLASS_DATA (expr1)->attr;
+	  gfc_change_class (&ts, &attr, NULL, expr1->rank, 0);
+	  tmp = gfc_create_var (gfc_typenode_for_spec (&ts), "ctmp");
+	  fcn_ss->info->class_container = tmp;
+
+	  /* Set the vptr and obtain the element size.  */
+	  vptr = gfc_class_vptr_get (tmp);
+	  gfc_add_modify (pre, vptr,
+			  fold_convert (TREE_TYPE (vptr),
+					gfc_class_vptr_get (class_expr)));
+	  elemsize = gfc_class_vtab_size_get (class_expr);
+	  elemsize = gfc_evaluate_now (elemsize, pre);
+
+	  /* Set the _len field, if necessary.  */
+	  if (UNLIMITED_POLY (expr1))
+	    gfc_add_modify (pre, gfc_class_len_get (tmp),
+			    gfc_class_len_get (class_expr));
+	}
 
       /* Assign the new descriptor to the _data field. This allows the
 	 vptr _copy to be used for scalarized assignment since the class
@@ -1588,11 +1654,25 @@ gfc_trans_create_temp_array (stmtblock_t * pre, stmtblock_t * post, gfc_ss * ss,
 			     TREE_TYPE (desc), desc);
       gfc_add_modify (pre, class_data, tmp);
 
-      /* Take the dtype from the class expression.  */
-      dtype = gfc_conv_descriptor_dtype (gfc_class_data_get (class_expr));
-      tmp = gfc_conv_descriptor_dtype (class_data);
-      gfc_add_modify (pre, tmp, dtype);
+      if (expr1 && expr1->expr_type == EXPR_FUNCTION
+	  && expr1->value.function.isym
+	  && (expr1->value.function.isym->id == GFC_ISYM_RESHAPE
+	      || expr1->value.function.isym->id == GFC_ISYM_UNPACK))
+	{
+	  /* Take the dtype from the class expression.  */
+	  dtype = gfc_conv_descriptor_dtype (gfc_class_data_get (class_expr));
+	  tmp = gfc_conv_descriptor_dtype (class_data);
+	  gfc_add_modify (pre, tmp, dtype);
 
+	  /* Transformational functions reshape and reduce can change the rank.  */
+	  if (fcn_ss && fcn_ss->info && fcn_ss->info->class_container)
+	    {
+	      tmp = gfc_conv_descriptor_rank (class_data);
+	      gfc_add_modify (pre, tmp,
+			      build_int_cst (TREE_TYPE (tmp), ss->loop->dimen));
+	      fcn_ss->info->class_container = NULL_TREE;
+	    }
+	}
       /* Point desc to the class _data field.  */
       desc = class_data;
     }
@@ -5990,6 +6070,14 @@ gfc_array_init_size (tree descriptor, int rank, int corank, tree * poffset,
       tmp = gfc_conv_descriptor_dtype (descriptor);
       gfc_add_modify (pblock, tmp, gfc_conv_descriptor_dtype (expr3_desc));
     }
+  else if (expr->ts.type == BT_CLASS
+	   && expr3 && expr3->ts.type != BT_CLASS
+	   && expr3_elem_size != NULL_TREE && expr3_desc == NULL_TREE)
+    {
+      tmp = gfc_conv_descriptor_elem_len (descriptor);
+      gfc_add_modify (pblock, tmp,
+		      fold_convert (TREE_TYPE (tmp), expr3_elem_size));
+    }
   else
     {
       tmp = gfc_conv_descriptor_dtype (descriptor);
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index feb43fd..3677e49 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -1226,6 +1226,21 @@ gfc_conv_class_to_class (gfc_se *parmse, gfc_expr *e, gfc_typespec class_ts,
   stmtblock_t block;
   bool full_array = false;
 
+  /* Class transformational function results are the data field of a class
+     temporary and so the class expression can be obtained directly.  */
+  if (e->expr_type == EXPR_FUNCTION
+      && e->value.function.isym
+      && e->value.function.isym->transformational
+      && TREE_CODE (parmse->expr) == COMPONENT_REF
+      && !GFC_CLASS_TYPE_P (TREE_TYPE (parmse->expr)))
+    {
+      parmse->expr = TREE_OPERAND (parmse->expr, 0);
+      if (!VAR_P (parmse->expr))
+	parmse->expr = gfc_evaluate_now (parmse->expr, &parmse->pre);
+      parmse->expr = gfc_build_addr_expr (NULL_TREE, parmse->expr);
+      return;
+    }
+
   gfc_init_block (&block);
 
   class_ref = NULL;
@@ -6326,7 +6341,7 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
   gfc_component *comp = NULL;
   int arglen;
   unsigned int argc;
-
+  tree arg1_cntnr = NULL_TREE;
   arglist = NULL;
   retargs = NULL;
   stringargs = NULL;
@@ -6334,6 +6349,8 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
   var = NULL_TREE;
   len = NULL_TREE;
   gfc_clear_ts (&ts);
+  gfc_intrinsic_sym *isym = expr && expr->rank ?
+			    expr->value.function.isym : NULL;
 
   comp = gfc_get_proc_ptr_comp (expr);
 
@@ -7428,6 +7445,19 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
 				    e->representation.length);
 	}
 
+      /* Make the class container for the first argument available with class
+	 valued transformational functions.  */
+      if (argc == 0 && e && e->ts.type == BT_CLASS
+	  && isym && isym->transformational
+	  && se->ss && se->ss->info)
+	{
+	  arg1_cntnr = parmse.expr;
+	  if (POINTER_TYPE_P (TREE_TYPE (arg1_cntnr)))
+	    arg1_cntnr = build_fold_indirect_ref_loc (input_location, arg1_cntnr);
+	  arg1_cntnr = gfc_get_class_from_expr (arg1_cntnr);
+	  se->ss->info->class_container = arg1_cntnr;
+	}
+
       if (fsym && e)
 	{
 	  /* Obtain the character length of an assumed character length
@@ -8029,6 +8059,7 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
 
 	  /* Set the type of the array.  */
 	  tmp = gfc_typenode_for_spec (&ts);
+	  tmp = arg1_cntnr ? TREE_TYPE (arg1_cntnr) : tmp;
 	  gcc_assert (se->ss->dimen == se->loop->dimen);
 
 	  /* Evaluate the bounds of the result, if known.  */
@@ -8309,8 +8340,7 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
 	 argument is actually given.  */
       arg = expr->value.function.actual;
       if (result && arg && expr->rank
-	  && expr->value.function.isym
-	  && expr->value.function.isym->transformational
+	  && isym && isym->transformational
 	  && arg->expr
 	  && arg->expr->ts.type == BT_DERIVED
 	  && arg->expr->ts.u.derived->attr.alloc_comp)
@@ -11255,7 +11285,7 @@ realloc_lhs_loop_for_fcn_call (gfc_se *se, locus *where, gfc_ss **ss,
    result to the original descriptor.  */
 
 static void
-fcncall_realloc_result (gfc_se *se, int rank)
+fcncall_realloc_result (gfc_se *se, int rank, tree dtype)
 {
   tree desc;
   tree res_desc;
@@ -11274,7 +11304,10 @@ fcncall_realloc_result (gfc_se *se, int rank)
 
   /* Unallocated, the descriptor does not have a dtype.  */
   tmp = gfc_conv_descriptor_dtype (desc);
-  gfc_add_modify (&se->pre, tmp, gfc_get_dtype (TREE_TYPE (desc)));
+  if (dtype != NULL_TREE)
+    gfc_add_modify (&se->pre, tmp, dtype);
+  else
+    gfc_add_modify (&se->pre, tmp, gfc_get_dtype (TREE_TYPE (desc)));
 
   res_desc = gfc_evaluate_now (desc, &se->pre);
   gfc_conv_descriptor_data_set (&se->pre, res_desc, null_pointer_node);
@@ -11491,7 +11524,19 @@ gfc_trans_arrayfunc_assign (gfc_expr * expr1, gfc_expr * expr2)
 	  ss->is_alloc_lhs = 1;
 	}
       else
-	fcncall_realloc_result (&se, expr1->rank);
+	{
+	  tree dtype = NULL_TREE;
+	  tree type = gfc_typenode_for_spec (&expr2->ts);
+	  if (expr1->ts.type == BT_CLASS)
+	    {
+	      tmp = gfc_class_vptr_get (sym->backend_decl);
+	      tree tmp2 = gfc_get_symbol_decl (gfc_find_vtab (&expr2->ts));
+	      tmp2 = gfc_build_addr_expr (TREE_TYPE (tmp), tmp2);
+	      gfc_add_modify (&se.pre, tmp, tmp2);
+	      dtype = gfc_get_dtype_rank_type (expr1->rank,type);
+	    }
+	  fcncall_realloc_result (&se, expr1->rank, dtype);
+	}
     }
 
   gfc_conv_function_expr (&se, expr2);