re PR fortran/50221 (Allocatable string length fails with array assignment)

2015-11-15  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/50221
	PR fortran/68216
	PR fortran/63932
	PR fortran/66408
	* trans_array.c (gfc_conv_scalarized_array_ref): Pass the
	symbol decl for deferred character length array references.
	* trans-stmt.c (gfc_trans_allocate): Keep the string lengths
	to update deferred length character string lengths.
	* trans-types.c (gfc_get_dtype_rank_type); Use the string
	length of deferred character types for the dtype size.
	* trans.c (gfc_build_array_ref): For references to deferred
	character arrays, use the domain max value, if it is a variable
	to set the 'span' and use pointer arithmetic for acces to the
	element.
	(trans_code): Set gfc_current_locus for diagnostic purposes.

	PR fortran/67674
	* trans-expr.c (gfc_conv_procedure_call): Do not fix deferred
	string lengths of components.

	PR fortran/49954
	* resolve.c (deferred_op_assign): New function.
	(gfc_resolve_code): Call it.
	* trans-array.c (concat_str_length): New function.
	(gfc_alloc_allocatable_for_assignment): Jump directly to alloc/
	realloc blocks for deferred character length arrays because the
	string length might change, even if the shape is the same. Call
	concat_str_length to obtain the string length for concatenation
	since it is needed to compute the lhs string length.
	Set the descriptor dtype appropriately for the new string
	length.
	* trans-expr.c (gfc_trans_assignment_1): Use the rse string
	length for all characters, other than deferred types. For
	concatenation operators, push the rse.pre block to the inner
	most loop so that the temporary pointer and the assignments
	are properly placed.

2015-11-15  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/50221
	* gfortran.dg/deferred_character_1.f90: New test.
	* gfortran.dg/deferred_character_4.f90: New test for comment
	#4 of the PR.

	PR fortran/68216
	* gfortran.dg/deferred_character_2.f90: New test.

	PR fortran/67674
	* gfortran.dg/deferred_character_3.f90: New test.

	PR fortran/63932
	* gfortran.dg/deferred_character_5.f90: New test.

	PR fortran/66408
	* gfortran.dg/deferred_character_6.f90: New test.

	PR fortran/49954
	* gfortran.dg/deferred_character_7.f90: New test.

From-SVN: r230396

6 files changed, 249 insertions, 11 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 5fdb866..1e6f404 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,42 @@
+2015-11-15  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/50221
+	PR fortran/68216
+	PR fortran/63932
+	PR fortran/66408
+	* trans_array.c (gfc_conv_scalarized_array_ref): Pass the
+	symbol decl for deferred character length array references.
+	* trans-stmt.c (gfc_trans_allocate): Keep the string lengths
+	to update deferred length character string lengths.
+	* trans-types.c (gfc_get_dtype_rank_type); Use the string
+	length of deferred character types for the dtype size.
+	* trans.c (gfc_build_array_ref): For references to deferred
+	character arrays, use the domain max value, if it is a variable
+	to set the 'span' and use pointer arithmetic for acces to the
+	element.
+	(trans_code): Set gfc_current_locus for diagnostic purposes.
+
+	PR fortran/67674
+	* trans-expr.c (gfc_conv_procedure_call): Do not fix deferred
+	string lengths of components.
+
+	PR fortran/49954
+	* resolve.c (deferred_op_assign): New function.
+	(gfc_resolve_code): Call it.
+	* trans-array.c (concat_str_length): New function.
+	(gfc_alloc_allocatable_for_assignment): Jump directly to alloc/
+	realloc blocks for deferred character length arrays because the
+	string length might change, even if the shape is the same. Call
+	concat_str_length to obtain the string length for concatenation
+	since it is needed to compute the lhs string length.
+	Set the descriptor dtype appropriately for the new string
+	length.
+	* trans-expr.c (gfc_trans_assignment_1): Use the rse string
+	length for all characters, other than deferred types. For
+	concatenation operators, push the rse.pre block to the inner
+	most loop so that the temporary pointer and the assignments
+	are properly placed.
+
 2015-11-14  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	PR fortran/67803
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index bf2837c..90bc6d4 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -10222,6 +10222,50 @@ resolve_ptr_fcn_assign (gfc_code **code, gfc_namespace *ns)
 }
 
 
+/* Deferred character length assignments from an operator expression
+   require a temporary because the character length of the lhs can
+   change in the course of the assignment.  */
+
+static bool
+deferred_op_assign (gfc_code **code, gfc_namespace *ns)
+{
+  gfc_expr *tmp_expr;
+  gfc_code *this_code;
+
+  if (!((*code)->expr1->ts.type == BT_CHARACTER
+	 && (*code)->expr1->ts.deferred && (*code)->expr1->rank
+	 && (*code)->expr2->expr_type == EXPR_OP))
+    return false;
+
+  if (!gfc_check_dependency ((*code)->expr1, (*code)->expr2, 1))
+    return false;
+
+  tmp_expr = get_temp_from_expr ((*code)->expr1, ns);
+  tmp_expr->where = (*code)->loc;
+
+  /* A new charlen is required to ensure that the variable string
+     length is different to that of the original lhs.  */
+  tmp_expr->ts.u.cl = gfc_get_charlen();
+  tmp_expr->symtree->n.sym->ts.u.cl = tmp_expr->ts.u.cl;
+  tmp_expr->ts.u.cl->next = (*code)->expr2->ts.u.cl->next;
+  (*code)->expr2->ts.u.cl->next = tmp_expr->ts.u.cl;
+
+  tmp_expr->symtree->n.sym->ts.deferred = 1;
+
+  this_code = build_assignment (EXEC_ASSIGN,
+				(*code)->expr1,
+				gfc_copy_expr (tmp_expr),
+				NULL, NULL, (*code)->loc);
+
+  (*code)->expr1 = tmp_expr;
+
+  this_code->next = (*code)->next;
+  (*code)->next = this_code;
+
+  return true;
+}
+
+
 /* Given a block of code, recursively resolve everything pointed to by this
    code block.  */
 
@@ -10427,6 +10471,11 @@ start:
 		goto call;
 	    }
 
+	  /* Check for dependencies in deferred character length array
+	     assignments and generate a temporary, if necessary.  */
+	  if (code->op == EXEC_ASSIGN && deferred_op_assign (&code, ns))
+	    break;
+
 	  /* F03 7.4.1.3 for non-allocatable, non-pointer components.  */
 	  if (code->op != EXEC_CALL && code->expr1->ts.type == BT_DERIVED
 	      && code->expr1->ts.u.derived
@@ -10801,7 +10850,7 @@ gfc_verify_binding_labels (gfc_symbol *sym)
       sym->binding_label = NULL;
 
     }
-  else if (sym->attr.flavor == FL_VARIABLE && module 
+  else if (sym->attr.flavor == FL_VARIABLE && module
 	   && (strcmp (module, gsym->mod_name) != 0
 	       || strcmp (sym->name, gsym->sym_name) != 0))
     {
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index c294516..69f6e19 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -3164,7 +3164,8 @@ gfc_conv_scalarized_array_ref (gfc_se * se, gfc_array_ref * ar)
     index = fold_build2_loc (input_location, PLUS_EXPR, gfc_array_index_type,
 			     index, info->offset);
 
-  if (expr && is_subref_array (expr))
+  if (expr && (is_subref_array (expr)
+	       || (expr->ts.deferred && expr->expr_type == EXPR_VARIABLE)))
     decl = expr->symtree->n.sym->backend_decl;
 
   tmp = build_fold_indirect_ref_loc (input_location, info->data);
@@ -8499,6 +8500,75 @@ gfc_is_reallocatable_lhs (gfc_expr *expr)
 }
 
 
+static tree
+concat_str_length (gfc_expr* expr)
+{
+  tree type;
+  tree len1;
+  tree len2;
+  gfc_se se;
+
+  type = gfc_typenode_for_spec (&expr->value.op.op1->ts);
+  len1 = TYPE_MAX_VALUE (TYPE_DOMAIN (type));
+  if (len1 == NULL_TREE)
+    {
+      if (expr->value.op.op1->expr_type == EXPR_OP)
+	len1 = concat_str_length (expr->value.op.op1);
+      else if (expr->value.op.op1->expr_type == EXPR_CONSTANT)
+	len1 = build_int_cst (gfc_charlen_type_node,
+			expr->value.op.op1->value.character.length);
+      else if (expr->value.op.op1->ts.u.cl->length)
+	{
+	  gfc_init_se (&se, NULL);
+	  gfc_conv_expr (&se, expr->value.op.op1->ts.u.cl->length);
+	  len1 = se.expr;
+	}
+      else
+	{
+	  /* Last resort!  */
+	  gfc_init_se (&se, NULL);
+	  se.want_pointer = 1;
+	  se.descriptor_only = 1;
+	  gfc_conv_expr (&se, expr->value.op.op1);
+	  len1 = se.string_length;
+	}
+    }
+
+  type = gfc_typenode_for_spec (&expr->value.op.op2->ts);
+  len2 = TYPE_MAX_VALUE (TYPE_DOMAIN (type));
+  if (len2 == NULL_TREE)
+    {
+      if (expr->value.op.op2->expr_type == EXPR_OP)
+	len2 = concat_str_length (expr->value.op.op2);
+      else if (expr->value.op.op2->expr_type == EXPR_CONSTANT)
+	len2 = build_int_cst (gfc_charlen_type_node,
+			expr->value.op.op2->value.character.length);
+      else if (expr->value.op.op2->ts.u.cl->length)
+	{
+	  gfc_init_se (&se, NULL);
+	  gfc_conv_expr (&se, expr->value.op.op2->ts.u.cl->length);
+	  len2 = se.expr;
+	}
+      else
+	{
+	  /* Last resort!  */
+	  gfc_init_se (&se, NULL);
+	  se.want_pointer = 1;
+	  se.descriptor_only = 1;
+	  gfc_conv_expr (&se, expr->value.op.op2);
+	  len2 = se.string_length;
+	}
+    }
+
+  gcc_assert(len1 && len2);
+  len1 = fold_convert (gfc_charlen_type_node, len1);
+  len2 = fold_convert (gfc_charlen_type_node, len2);
+
+  return fold_build2_loc (input_location, PLUS_EXPR,
+			  gfc_charlen_type_node, len1, len2);
+}
+
+
 /* Allocate the lhs of an assignment to an allocatable array, otherwise
    reallocate it.  */
 
@@ -8596,6 +8666,12 @@ gfc_alloc_allocatable_for_assignment (gfc_loopinfo *loop,
   /* Allocate if data is NULL.  */
   cond_null = fold_build2_loc (input_location, EQ_EXPR, boolean_type_node,
 			 array1, build_int_cst (TREE_TYPE (array1), 0));
+
+  if (expr1->ts.deferred)
+    cond_null = gfc_evaluate_now (boolean_true_node, &fblock);
+  else
+    cond_null= gfc_evaluate_now (cond_null, &fblock);
+
   tmp = build3_v (COND_EXPR, cond_null,
 		  build1_v (GOTO_EXPR, jump_label1),
 		  build_empty_stmt (input_location));
@@ -8684,7 +8760,13 @@ gfc_alloc_allocatable_for_assignment (gfc_loopinfo *loop,
 
   cond = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
 			  size1, size2);
-  neq_size = gfc_evaluate_now (cond, &fblock);
+
+  /* If the lhs is deferred length, assume that the element size
+     changes and force a reallocation.  */
+  if (expr1->ts.deferred)
+    neq_size = gfc_evaluate_now (boolean_true_node, &fblock);
+  else
+    neq_size = gfc_evaluate_now (cond, &fblock);
 
   /* Deallocation of allocatable components will have to occur on
      reallocation.  Fix the old descriptor now.  */
@@ -8789,6 +8871,12 @@ gfc_alloc_allocatable_for_assignment (gfc_loopinfo *loop,
       else
 	{
 	  tmp = expr2->ts.u.cl->backend_decl;
+	  if (!tmp && expr2->expr_type == EXPR_OP
+	      && expr2->value.op.op == INTRINSIC_CONCAT)
+	    {
+	      tmp = concat_str_length (expr2);
+	      expr2->ts.u.cl->backend_decl = gfc_evaluate_now (tmp, &fblock);
+	    }
 	  tmp = fold_convert (TREE_TYPE (expr1->ts.u.cl->backend_decl), tmp);
 	}
 
@@ -8816,6 +8904,22 @@ gfc_alloc_allocatable_for_assignment (gfc_loopinfo *loop,
 			   size2, size_one_node);
   size2 = gfc_evaluate_now (size2, &fblock);
 
+  /* For deferred character length, the 'size' field of the dtype might
+     have changed so set the dtype.  */
+  if (GFC_DESCRIPTOR_TYPE_P (TREE_TYPE (desc))
+      && expr1->ts.type == BT_CHARACTER && expr1->ts.deferred)
+    {
+      tree type;
+      tmp = gfc_conv_descriptor_dtype (desc);
+      if (expr2->ts.u.cl->backend_decl)
+	type = gfc_typenode_for_spec (&expr2->ts);
+      else
+	type = gfc_typenode_for_spec (&expr1->ts);
+
+      gfc_add_modify (&fblock, tmp,
+		      gfc_get_dtype_rank_type (expr1->rank,type));
+    }
+
   /* Realloc expression.  Note that the scalarizer uses desc.data
      in the array reference - (*desc.data)[<element>].  */
   gfc_init_block (&realloc_block);
@@ -8858,8 +8962,16 @@ gfc_alloc_allocatable_for_assignment (gfc_loopinfo *loop,
 			     1, size2);
   gfc_conv_descriptor_data_set (&alloc_block,
 				desc, tmp);
-  tmp = gfc_conv_descriptor_dtype (desc);
-  gfc_add_modify (&alloc_block, tmp, gfc_get_dtype (TREE_TYPE (desc)));
+
+  /* We already set the dtype in the case of deferred character
+     length arrays.  */
+  if (!(GFC_DESCRIPTOR_TYPE_P (TREE_TYPE (desc))
+        && expr1->ts.type == BT_CHARACTER && expr1->ts.deferred))
+    {
+      tmp = gfc_conv_descriptor_dtype (desc);
+      gfc_add_modify (&alloc_block, tmp, gfc_get_dtype (TREE_TYPE (desc)));
+    }
+
   if ((expr1->ts.type == BT_DERIVED)
 	&& expr1->ts.u.derived->attr.alloc_comp)
     {
diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index 8515315..6647a4e 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -5599,7 +5599,8 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
 	  else
 	    {
 	      tmp = parmse.string_length;
-	      if (TREE_CODE (tmp) != VAR_DECL)
+	      if (TREE_CODE (tmp) != VAR_DECL
+		  && TREE_CODE (tmp) != COMPONENT_REF)
 		tmp = gfc_evaluate_now (parmse.string_length, &se->pre);
 	      parmse.string_length = gfc_build_addr_expr (NULL_TREE, tmp);
 	    }
@@ -9250,8 +9251,10 @@ gfc_trans_assignment_1 (gfc_expr * expr1, gfc_expr * expr2, bool init_flag,
     }
 
   /* Stabilize a string length for temporaries.  */
-  if (expr2->ts.type == BT_CHARACTER)
+  if (expr2->ts.type == BT_CHARACTER && !expr2->ts.deferred)
     string_length = gfc_evaluate_now (rse.string_length, &rse.pre);
+  else if (expr2->ts.type == BT_CHARACTER)
+    string_length = rse.string_length;
   else
     string_length = NULL_TREE;
 
@@ -9285,8 +9288,14 @@ gfc_trans_assignment_1 (gfc_expr * expr1, gfc_expr * expr2, bool init_flag,
      the function call must happen before the (re)allocation of the lhs -
      otherwise the character length of the result is not known.
      NOTE: This relies on having the exact dependence of the length type
-     parameter available to the caller; gfortran saves it in the .mod files.  */
-  if (flag_realloc_lhs && expr2->ts.type == BT_CHARACTER && expr1->ts.deferred)
+     parameter available to the caller; gfortran saves it in the .mod files.
+     NOTE ALSO: The concatenation operation generates a temporary pointer,
+     whose allocation must go to the innermost loop.  */
+  if (flag_realloc_lhs
+      && expr2->ts.type == BT_CHARACTER && expr1->ts.deferred
+      && !(lss != gfc_ss_terminator
+	   && expr2->expr_type == EXPR_OP
+	   && expr2->value.op.op == INTRINSIC_CONCAT))
     gfc_add_block_to_block (&block, &rse.pre);
 
   /* Nullify the allocatable components corresponding to those of the lhs
diff --git a/gcc/fortran/trans-stmt.c b/gcc/fortran/trans-stmt.c
index 1af2ad1..86548c0 100644
--- a/gcc/fortran/trans-stmt.c
+++ b/gcc/fortran/trans-stmt.c
@@ -5086,6 +5086,7 @@ gfc_trans_allocate (gfc_code * code)
   tree label_finish;
   tree memsz;
   tree al_vptr, al_len;
+  tree def_str_len = NULL_TREE;
   /* If an expr3 is present, then store the tree for accessing its
      _vptr, and _len components in the variables, respectively.  The
      element size, i.e. _vptr%size, is stored in expr3_esize.  Any of
@@ -5463,6 +5464,7 @@ gfc_trans_allocate (gfc_code * code)
 	  expr3_esize = fold_build2_loc (input_location, MULT_EXPR,
 					 TREE_TYPE (se_sz.expr),
 					 tmp, se_sz.expr);
+	  def_str_len = gfc_evaluate_now (se_sz.expr, &block);
 	}
     }
 
@@ -5514,6 +5516,17 @@ gfc_trans_allocate (gfc_code * code)
 
       se.want_pointer = 1;
       se.descriptor_only = 1;
+
+      if (expr->ts.type == BT_CHARACTER
+	  && expr->ts.deferred
+	  && TREE_CODE (expr->ts.u.cl->backend_decl) == VAR_DECL
+	  && def_str_len != NULL_TREE)
+	{
+	  tmp = expr->ts.u.cl->backend_decl;
+	  gfc_add_modify (&block, tmp,
+			  fold_convert (TREE_TYPE (tmp), def_str_len));
+	}
+
       gfc_conv_expr (&se, expr);
       if (expr->ts.type == BT_CHARACTER && expr->ts.deferred)
 	/* se.string_length now stores the .string_length variable of expr
diff --git a/gcc/fortran/trans.c b/gcc/fortran/trans.c
index d9ab346..9b44b71 100644
--- a/gcc/fortran/trans.c
+++ b/gcc/fortran/trans.c
@@ -331,6 +331,18 @@ gfc_build_array_ref (tree base, tree offset, tree decl, tree vptr)
 
   type = TREE_TYPE (type);
 
+  /* Use pointer arithmetic for deferred character length array
+     references.  */
+  if (type && TREE_CODE (type) == ARRAY_TYPE
+      && TYPE_MAXVAL (TYPE_DOMAIN (type)) != NULL_TREE
+      && TREE_CODE (TYPE_MAXVAL (TYPE_DOMAIN (type))) == VAR_DECL
+      && decl
+      && DECL_CONTEXT (TYPE_MAXVAL (TYPE_DOMAIN (type)))
+					== DECL_CONTEXT (decl))
+    span = TYPE_MAXVAL (TYPE_DOMAIN (type));
+  else
+    span = NULL_TREE;
+
   if (DECL_P (base))
     TREE_ADDRESSABLE (base) = 1;
 
@@ -345,8 +357,9 @@ gfc_build_array_ref (tree base, tree offset, tree decl, tree vptr)
 		|| TREE_CODE (decl) == PARM_DECL)
        && ((GFC_DECL_SUBREF_ARRAY_P (decl)
 	    && !integer_zerop (GFC_DECL_SPAN (decl)))
-	   || GFC_DECL_CLASS (decl)))
-      || vptr)
+	   || GFC_DECL_CLASS (decl)
+	   || span != NULL_TREE))
+      || vptr != NULL_TREE)
     {
       if (decl)
 	{
@@ -376,6 +389,8 @@ gfc_build_array_ref (tree base, tree offset, tree decl, tree vptr)
 	    }
 	  else if (GFC_DECL_SUBREF_ARRAY_P (decl))
 	    span = GFC_DECL_SPAN (decl);
+	  else if (span)
+	    span = fold_convert (gfc_array_index_type, span);
 	  else
 	    gcc_unreachable ();
 	}
@@ -1620,6 +1635,7 @@ trans_code (gfc_code * code, tree cond)
 	  gfc_add_expr_to_block (&block, res);
 	}
 
+      gfc_current_locus = code->loc;
       gfc_set_backend_locus (&code->loc);
 
       switch (code->op)