1 /* Code translation -- generate GCC trees from gfc_code.
2 Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
3 Contributed by Paul Brook
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
24 #include "coretypes.h"
26 #include "tree-gimple.h"
33 #include "trans-stmt.h"
34 #include "trans-array.h"
35 #include "trans-types.h"
36 #include "trans-const.h"
38 /* Naming convention for backend interface code:
40 gfc_trans_* translate gfc_code into STMT trees.
42 gfc_conv_* expression conversion
44 gfc_get_* get a backend tree representation of a decl or type */
46 static gfc_file *gfc_current_backend_file;
49 /* Advance along TREE_CHAIN n times. */
52 gfc_advance_chain (tree t, int n)
56 gcc_assert (t != NULL_TREE);
63 /* Wrap a node in a TREE_LIST node and add it to the end of a list. */
66 gfc_chainon_list (tree list, tree add)
70 l = tree_cons (NULL_TREE, add, NULL_TREE);
72 return chainon (list, l);
76 /* Strip off a legitimate source ending from the input
77 string NAME of length LEN. */
80 remove_suffix (char *name, int len)
84 for (i = 2; i < 8 && len > i; i++)
86 if (name[len - i] == '.')
95 /* Creates a variable declaration with a given TYPE. */
98 gfc_create_var_np (tree type, const char *prefix)
100 return create_tmp_var_raw (type, prefix);
104 /* Like above, but also adds it to the current scope. */
107 gfc_create_var (tree type, const char *prefix)
111 tmp = gfc_create_var_np (type, prefix);
119 /* If the an expression is not constant, evaluate it now. We assign the
120 result of the expression to an artificially created variable VAR, and
121 return a pointer to the VAR_DECL node for this variable. */
124 gfc_evaluate_now (tree expr, stmtblock_t * pblock)
128 if (CONSTANT_CLASS_P (expr))
131 var = gfc_create_var (TREE_TYPE (expr), NULL);
132 gfc_add_modify_expr (pblock, var, expr);
138 /* Build a MODIFY_EXPR node and add it to a given statement block PBLOCK.
139 A MODIFY_EXPR is an assignment: LHS <- RHS. */
142 gfc_add_modify_expr (stmtblock_t * pblock, tree lhs, tree rhs)
146 #ifdef ENABLE_CHECKING
147 /* Make sure that the types of the rhs and the lhs are the same
148 for scalar assignments. We should probably have something
149 similar for aggregates, but right now removing that check just
150 breaks everything. */
151 gcc_assert (TREE_TYPE (rhs) == TREE_TYPE (lhs)
152 || AGGREGATE_TYPE_P (TREE_TYPE (lhs)));
155 tmp = fold_build2 (MODIFY_EXPR, void_type_node, lhs, rhs);
156 gfc_add_expr_to_block (pblock, tmp);
160 /* Create a new scope/binding level and initialize a block. Care must be
161 taken when translating expressions as any temporaries will be placed in
162 the innermost scope. */
165 gfc_start_block (stmtblock_t * block)
167 /* Start a new binding level. */
169 block->has_scope = 1;
171 /* The block is empty. */
172 block->head = NULL_TREE;
176 /* Initialize a block without creating a new scope. */
179 gfc_init_block (stmtblock_t * block)
181 block->head = NULL_TREE;
182 block->has_scope = 0;
186 /* Sometimes we create a scope but it turns out that we don't actually
187 need it. This function merges the scope of BLOCK with its parent.
188 Only variable decls will be merged, you still need to add the code. */
191 gfc_merge_block_scope (stmtblock_t * block)
196 gcc_assert (block->has_scope);
197 block->has_scope = 0;
199 /* Remember the decls in this scope. */
203 /* Add them to the parent scope. */
204 while (decl != NULL_TREE)
206 next = TREE_CHAIN (decl);
207 TREE_CHAIN (decl) = NULL_TREE;
215 /* Finish a scope containing a block of statements. */
218 gfc_finish_block (stmtblock_t * stmtblock)
224 expr = stmtblock->head;
226 expr = build_empty_stmt ();
228 stmtblock->head = NULL_TREE;
230 if (stmtblock->has_scope)
236 block = poplevel (1, 0, 0);
237 expr = build3_v (BIND_EXPR, decl, expr, block);
247 /* Build an ADDR_EXPR and cast the result to TYPE. If TYPE is NULL, the
248 natural type is used. */
251 gfc_build_addr_expr (tree type, tree t)
253 tree base_type = TREE_TYPE (t);
256 if (type && POINTER_TYPE_P (type)
257 && TREE_CODE (base_type) == ARRAY_TYPE
258 && TYPE_MAIN_VARIANT (TREE_TYPE (type))
259 == TYPE_MAIN_VARIANT (TREE_TYPE (base_type)))
262 natural_type = build_pointer_type (base_type);
264 if (TREE_CODE (t) == INDIRECT_REF)
268 t = TREE_OPERAND (t, 0);
269 natural_type = TREE_TYPE (t);
274 TREE_ADDRESSABLE (t) = 1;
275 t = build1 (ADDR_EXPR, natural_type, t);
278 if (type && natural_type != type)
279 t = convert (type, t);
285 /* Build an ARRAY_REF with its natural type. */
288 gfc_build_array_ref (tree base, tree offset)
290 tree type = TREE_TYPE (base);
291 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
292 type = TREE_TYPE (type);
295 TREE_ADDRESSABLE (base) = 1;
297 return build4 (ARRAY_REF, type, base, offset, NULL_TREE, NULL_TREE);
301 /* Generate a runtime error if COND is true. */
304 gfc_trans_runtime_check (tree cond, tree msg, stmtblock_t * pblock)
311 if (integer_zerop (cond))
314 /* The code to generate the error. */
315 gfc_start_block (&block);
317 gcc_assert (TREE_CODE (msg) == STRING_CST);
321 tmp = gfc_build_addr_expr (pchar_type_node, msg);
322 args = gfc_chainon_list (NULL_TREE, tmp);
324 tmp = gfc_build_addr_expr (pchar_type_node, gfc_strconst_current_filename);
325 args = gfc_chainon_list (args, tmp);
327 tmp = build_int_cst (NULL_TREE, input_line);
328 args = gfc_chainon_list (args, tmp);
330 tmp = build_function_call_expr (gfor_fndecl_runtime_error, args);
331 gfc_add_expr_to_block (&block, tmp);
333 body = gfc_finish_block (&block);
335 if (integer_onep (cond))
337 gfc_add_expr_to_block (pblock, body);
341 /* Tell the compiler that this isn't likely. */
342 tmp = gfc_chainon_list (NULL_TREE, cond);
343 tmp = gfc_chainon_list (tmp, integer_zero_node);
344 cond = build_function_call_expr (built_in_decls[BUILT_IN_EXPECT], tmp);
346 tmp = build3_v (COND_EXPR, cond, body, build_empty_stmt ());
347 gfc_add_expr_to_block (pblock, tmp);
352 /* Add a statement to a block. */
355 gfc_add_expr_to_block (stmtblock_t * block, tree expr)
359 if (expr == NULL_TREE || IS_EMPTY_STMT (expr))
362 if (TREE_CODE (expr) != STATEMENT_LIST
363 && TREE_CODE_CLASS (TREE_CODE (expr)) != tcc_statement)
368 if (TREE_CODE (block->head) != STATEMENT_LIST)
373 block->head = NULL_TREE;
374 append_to_statement_list (tmp, &block->head);
376 append_to_statement_list (expr, &block->head);
379 /* Don't bother creating a list if we only have a single statement. */
384 /* Add a block the end of a block. */
387 gfc_add_block_to_block (stmtblock_t * block, stmtblock_t * append)
390 gcc_assert (!append->has_scope);
392 gfc_add_expr_to_block (block, append->head);
393 append->head = NULL_TREE;
397 /* Get the current locus. The structure may not be complete, and should
398 only be used with gfc_set_backend_locus. */
401 gfc_get_backend_locus (locus * loc)
403 loc->lb = gfc_getmem (sizeof (gfc_linebuf));
404 #ifdef USE_MAPPED_LOCATION
405 loc->lb->location = input_location;
407 loc->lb->linenum = input_line;
409 loc->lb->file = gfc_current_backend_file;
413 /* Set the current locus. */
416 gfc_set_backend_locus (locus * loc)
418 gfc_current_backend_file = loc->lb->file;
419 #ifdef USE_MAPPED_LOCATION
420 input_location = loc->lb->location;
422 input_line = loc->lb->linenum;
423 input_filename = loc->lb->file->filename;
428 /* Translate an executable statement. */
431 gfc_trans_code (gfc_code * code)
437 return build_empty_stmt ();
439 gfc_start_block (&block);
441 /* Translate statements one by one to GIMPLE trees until we reach
442 the end of this gfc_code branch. */
443 for (; code; code = code->next)
447 res = gfc_trans_label_here (code);
448 gfc_add_expr_to_block (&block, res);
458 res = gfc_trans_assign (code);
461 case EXEC_LABEL_ASSIGN:
462 res = gfc_trans_label_assign (code);
465 case EXEC_POINTER_ASSIGN:
466 res = gfc_trans_pointer_assign (code);
474 res = gfc_trans_cycle (code);
478 res = gfc_trans_exit (code);
482 res = gfc_trans_goto (code);
486 res = gfc_trans_entry (code);
490 res = gfc_trans_pause (code);
494 res = gfc_trans_stop (code);
498 res = gfc_trans_call (code);
502 res = gfc_trans_return (code);
506 res = gfc_trans_if (code);
509 case EXEC_ARITHMETIC_IF:
510 res = gfc_trans_arithmetic_if (code);
514 res = gfc_trans_do (code);
518 res = gfc_trans_do_while (code);
522 res = gfc_trans_select (code);
526 res = gfc_trans_flush (code);
530 res = gfc_trans_forall (code);
534 res = gfc_trans_where (code);
538 res = gfc_trans_allocate (code);
541 case EXEC_DEALLOCATE:
542 res = gfc_trans_deallocate (code);
546 res = gfc_trans_open (code);
550 res = gfc_trans_close (code);
554 res = gfc_trans_read (code);
558 res = gfc_trans_write (code);
562 res = gfc_trans_iolength (code);
566 res = gfc_trans_backspace (code);
570 res = gfc_trans_endfile (code);
574 res = gfc_trans_inquire (code);
578 res = gfc_trans_rewind (code);
582 res = gfc_trans_transfer (code);
586 res = gfc_trans_dt_end (code);
590 internal_error ("gfc_trans_code(): Bad statement code");
593 gfc_set_backend_locus (&code->loc);
595 if (res != NULL_TREE && ! IS_EMPTY_STMT (res))
597 if (TREE_CODE (res) == STATEMENT_LIST)
598 annotate_all_with_locus (&res, input_location);
600 SET_EXPR_LOCATION (res, input_location);
602 /* Add the new statement to the block. */
603 gfc_add_expr_to_block (&block, res);
607 /* Return the finished block. */
608 return gfc_finish_block (&block);
612 /* This function is called after a complete program unit has been parsed
616 gfc_generate_code (gfc_namespace * ns)
618 if (ns->is_block_data)
620 gfc_generate_block_data (ns);
624 gfc_generate_function_code (ns);
628 /* This function is called after a complete module has been parsed
632 gfc_generate_module_code (gfc_namespace * ns)
636 gfc_generate_module_vars (ns);
638 /* We need to generate all module function prototypes first, to allow
640 for (n = ns->contained; n; n = n->sibling)
645 gfc_create_function_decl (n);
648 for (n = ns->contained; n; n = n->sibling)
653 gfc_generate_function_code (n);