1 /* Convert language-specific tree expression to rtl instructions,
3 Copyright (C) 1988, 92-97, 1998 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
33 static tree extract_aggr_init PROTO((tree, tree));
34 static tree extract_scalar_init PROTO((tree, tree));
36 static rtx cplus_expand_expr PROTO((tree, rtx, enum machine_mode,
37 enum expand_modifier));
39 /* Hook used by output_constant to expand language-specific
43 cplus_expand_constant (cst)
46 switch (TREE_CODE (cst))
50 tree type = TREE_TYPE (cst);
54 /* Find the member. */
55 member = PTRMEM_CST_MEMBER (cst);
57 if (TREE_CODE (member) == FIELD_DECL)
59 /* Find the offset for the field. */
60 offset = convert (sizetype,
61 size_binop (EASY_DIV_EXPR,
62 DECL_FIELD_BITPOS (member),
63 size_int (BITS_PER_UNIT)));
65 /* We offset all pointer to data members by 1 so that we
66 can distinguish between a null pointer to data member
67 and the first data member of a structure. */
68 offset = size_binop (PLUS_EXPR, offset, size_int (1));
70 cst = cp_convert (type, offset);
79 expand_ptrmemfunc_cst (cst, &delta, &idx, &pfn, &delta2);
81 cst = build_ptrmemfunc1 (type, delta, idx,
88 /* There's nothing to do. */
95 /* Hook used by expand_expr to expand language-specific tree codes. */
98 cplus_expand_expr (exp, target, tmode, modifier)
101 enum machine_mode tmode;
102 enum expand_modifier modifier;
104 tree type = TREE_TYPE (exp);
105 register enum machine_mode mode = TYPE_MODE (type);
106 register enum tree_code code = TREE_CODE (exp);
107 int ignore = target == const0_rtx;
112 /* No sense saving up arithmetic to be done
113 if it's all in the wrong mode to form part of an address.
114 And force_operand won't know whether to sign-extend or zero-extend. */
116 if (mode != Pmode && modifier == EXPAND_SUM)
117 modifier = EXPAND_NORMAL;
123 /* Something needs to be initialized, but we didn't know
124 where that thing was when building the tree. For example,
125 it could be the return value of a function, or a parameter
126 to a function which lays down in the stack, or a temporary
127 variable which must be passed by reference.
129 Cleanups are handled in a language-specific way: they
130 might be run by the called function (true in GNU C++
131 for parameters with cleanups), or they might be
132 run by the caller, after the call (true in GNU C++
133 for other cleanup needs). */
135 tree func = TREE_OPERAND (exp, 0);
136 tree args = TREE_OPERAND (exp, 1);
137 tree type = TREE_TYPE (exp), slot;
139 rtx call_target, return_target;
140 int pcc_struct_return = 0;
142 /* The expression `init' wants to initialize what
143 `target' represents. SLOT holds the slot for TARGET. */
144 slot = TREE_OPERAND (exp, 2);
146 /* Should always be called with a target. */
147 my_friendly_assert (target != NULL_RTX, 205);
149 /* The target the initializer will initialize (CALL_TARGET)
150 must now be directed to initialize the target we are
151 supposed to initialize (TARGET). The semantics for
152 choosing what CALL_TARGET is is language-specific,
153 as is building the call which will perform the
154 initialization. It is left here to show the choices that
157 if (TREE_CODE (func) == ADDR_EXPR
158 && TREE_CODE (TREE_OPERAND (func, 0)) == FUNCTION_DECL
159 && DECL_CONSTRUCTOR_P (TREE_OPERAND (func, 0)))
161 type = build_pointer_type (type);
162 /* Don't clobber a value that might be part of a default
164 mark_addressable (slot);
165 if (TREE_PERMANENT (args))
166 args = expr_tree_cons (0, build1 (ADDR_EXPR, type, slot),
169 TREE_VALUE (args) = build1 (ADDR_EXPR, type, slot);
174 call_target = target;
175 #ifdef PCC_STATIC_STRUCT_RETURN
176 if (aggregate_value_p (type))
178 pcc_struct_return = 1;
184 call_exp = build (CALL_EXPR, type, func, args, NULL_TREE);
185 TREE_SIDE_EFFECTS (call_exp) = 1;
186 return_target = expand_call (call_exp, call_target, ignore);
189 /* Trust that the right thing has been done; it's too hard to
191 return return_target;
193 /* If we're suffering under the ancient PCC_STATIC_STRUCT_RETURN
194 calling convention, we need to copy the return value out of
195 the static return buffer into slot. */
196 if (pcc_struct_return)
198 extern int flag_access_control;
199 int old_ac = flag_access_control;
201 tree init = build_decl (VAR_DECL, NULL_TREE,
202 build_reference_type (type));
203 DECL_RTL (init) = XEXP (return_target, 0);
204 init = convert_from_reference (init);
206 flag_access_control = 0;
207 expand_aggr_init (slot, init, LOOKUP_ONLYCONVERTING);
208 flag_access_control = old_ac;
210 if (TYPE_NEEDS_DESTRUCTOR (type))
212 init = maybe_build_cleanup (init);
213 if (init != NULL_TREE)
214 expand_expr (init, const0_rtx, VOIDmode, 0);
218 return DECL_RTL (slot);
222 return expand_expr (cplus_expand_constant (exp),
223 target, tmode, modifier);
227 return expand_expr (default_conversion (resolve_offset_ref (exp)),
228 target, tmode, EXPAND_NORMAL);
232 return DECL_RTL (exp);
235 expand_throw (TREE_OPERAND (exp, 0));
241 (NULL_TREE, TREE_OPERAND (exp, 0),
242 build_binary_op (MINUS_EXPR, TREE_OPERAND (exp, 2),
244 TREE_OPERAND (exp, 1), 0), target, tmode, modifier);
247 return expand_expr (build_new_1 (exp), target, tmode, modifier);
252 my_friendly_abort (40);
260 lang_expand_expr = cplus_expand_expr;
261 lang_expand_constant = cplus_expand_constant;
264 /* If DECL had its rtl moved from where callers expect it
265 to be, fix it up. RESULT is the nominal rtl for the RESULT_DECL,
266 which may be a pseudo instead of a hard register. */
269 fixup_result_decl (decl, result)
275 if (REGNO (result) >= FIRST_PSEUDO_REGISTER)
277 rtx real_decl_result;
279 #ifdef FUNCTION_OUTGOING_VALUE
281 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl), current_function_decl);
284 = FUNCTION_VALUE (TREE_TYPE (decl), current_function_decl);
286 REG_FUNCTION_VALUE_P (real_decl_result) = 1;
287 result = real_decl_result;
289 store_expr (decl, result, 0);
290 emit_insn (gen_rtx (USE, VOIDmode, result));
295 /* Expand this initialization inline and see if it's simple enough that
296 it can be done at compile-time. */
299 extract_aggr_init (decl, init)
306 extract_scalar_init (decl, init)
309 rtx value, insns, insn;
310 extern struct obstack temporary_obstack;
313 push_obstacks (&temporary_obstack, &temporary_obstack);
315 value = expand_expr (init, NULL_RTX, VOIDmode, 0);
316 insns = get_insns ();
318 reg_scan (insns, max_reg_num (), 0);
319 jump_optimize (insns, 0, 0, 1);
322 for (insn = insns; insn; insn = NEXT_INSN (insn))
326 if (GET_CODE (insn) == NOTE)
328 else if (GET_CODE (insn) != INSN)
332 if (GET_CODE (r) != SET)
338 || (GET_CODE (to) == SUBREG && XEXP (to, 0) == value)))
343 switch (GET_CODE (r))
346 t = build_int_2 (XEXP (r, 0), 0);
358 extract_init (decl, init)
359 tree decl ATTRIBUTE_UNUSED, init ATTRIBUTE_UNUSED;
364 if (IS_AGGR_TYPE (TREE_TYPE (decl))
365 || TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
366 init = extract_aggr_init (decl, init);
368 init = extract_scalar_init (decl, init);
370 if (init == NULL_TREE)
373 DECL_INITIAL (decl) = init;
382 tree value1 = NULL_TREE, value2 = NULL_TREE, label;
384 if (start != NULL_TREE && TREE_TYPE (start) != NULL_TREE
385 && POINTER_TYPE_P (TREE_TYPE (start)))
386 error ("pointers are not permitted as case values");
389 pedwarn ("ANSI C++ forbids range expressions in switch statement");
391 if (processing_template_decl)
393 add_tree (build_min_nt (CASE_LABEL, start, end));
398 value1 = check_cp_case_value (start);
400 value2 = check_cp_case_value (end);
402 label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
404 if (value1 != error_mark_node
405 && value2 != error_mark_node)
411 success = pushcase_range (value1, value2, convert_and_check,
414 success = pushcase (value1, convert_and_check, label, &duplicate);
416 success = pushcase (NULL_TREE, 0, label, &duplicate);
421 error ("case label not within a switch statement");
423 cp_error ("case label `%E' not within a switch statement", start);
425 error ("default label not within a switch statement");
427 else if (success == 2)
431 error ("duplicate (or overlapping) case value");
432 cp_error_at ("this is the first entry overlapping that value",
437 cp_error ("duplicate case value `%E'", start);
438 cp_error_at ("previously used here", duplicate);
442 error ("multiple default labels in one switch");
443 cp_error_at ("this is the first default label", duplicate);
446 else if (success == 3)
447 warning ("case value out of range");
448 else if (success == 4)
449 warning ("empty range specified");
450 else if (success == 5)
453 error ("case label within scope of cleanup or variable array");
455 error ("`default' label within scope of cleanup or variable array");
457 cp_error ("case label `%E' within scope of cleanup or variable array", start);
460 define_case_label ();