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 expand_expr to expand language-specific tree codes. */
42 cplus_expand_expr (exp
, target
, tmode
, modifier
)
45 enum machine_mode tmode
;
46 enum expand_modifier modifier
;
48 tree type
= TREE_TYPE (exp
);
49 register enum machine_mode mode
= TYPE_MODE (type
);
50 register enum tree_code code
= TREE_CODE (exp
);
51 int ignore
= target
== const0_rtx
;
56 /* No sense saving up arithmetic to be done
57 if it's all in the wrong mode to form part of an address.
58 And force_operand won't know whether to sign-extend or zero-extend. */
60 if (mode
!= Pmode
&& modifier
== EXPAND_SUM
)
61 modifier
= EXPAND_NORMAL
;
67 /* Something needs to be initialized, but we didn't know
68 where that thing was when building the tree. For example,
69 it could be the return value of a function, or a parameter
70 to a function which lays down in the stack, or a temporary
71 variable which must be passed by reference.
73 Cleanups are handled in a language-specific way: they
74 might be run by the called function (true in GNU C++
75 for parameters with cleanups), or they might be
76 run by the caller, after the call (true in GNU C++
77 for other cleanup needs). */
79 tree func
= TREE_OPERAND (exp
, 0);
80 tree args
= TREE_OPERAND (exp
, 1);
81 tree type
= TREE_TYPE (exp
), slot
;
83 rtx call_target
, return_target
;
84 int pcc_struct_return
= 0;
86 /* The expression `init' wants to initialize what
87 `target' represents. SLOT holds the slot for TARGET. */
88 slot
= TREE_OPERAND (exp
, 2);
90 /* Should always be called with a target. */
91 my_friendly_assert (target
!= NULL_RTX
, 205);
93 /* The target the initializer will initialize (CALL_TARGET)
94 must now be directed to initialize the target we are
95 supposed to initialize (TARGET). The semantics for
96 choosing what CALL_TARGET is is language-specific,
97 as is building the call which will perform the
98 initialization. It is left here to show the choices that
101 if (TREE_CODE (func
) == ADDR_EXPR
102 && TREE_CODE (TREE_OPERAND (func
, 0)) == FUNCTION_DECL
103 && DECL_CONSTRUCTOR_P (TREE_OPERAND (func
, 0)))
105 type
= build_pointer_type (type
);
106 /* Don't clobber a value that might be part of a default
108 mark_addressable (slot
);
109 if (TREE_PERMANENT (args
))
110 args
= expr_tree_cons (0, build1 (ADDR_EXPR
, type
, slot
),
113 TREE_VALUE (args
) = build1 (ADDR_EXPR
, type
, slot
);
118 call_target
= target
;
119 #ifdef PCC_STATIC_STRUCT_RETURN
120 if (aggregate_value_p (type
))
122 pcc_struct_return
= 1;
128 call_exp
= build (CALL_EXPR
, type
, func
, args
, NULL_TREE
);
129 TREE_SIDE_EFFECTS (call_exp
) = 1;
130 return_target
= expand_call (call_exp
, call_target
, ignore
);
133 /* Trust that the right thing has been done; it's too hard to
135 return return_target
;
137 /* If we're suffering under the ancient PCC_STATIC_STRUCT_RETURN
138 calling convention, we need to copy the return value out of
139 the static return buffer into slot. */
140 if (pcc_struct_return
)
142 extern int flag_access_control
;
143 int old_ac
= flag_access_control
;
145 tree init
= build_decl (VAR_DECL
, NULL_TREE
,
146 build_reference_type (type
));
147 DECL_RTL (init
) = XEXP (return_target
, 0);
148 init
= convert_from_reference (init
);
150 flag_access_control
= 0;
151 expand_aggr_init (slot
, init
, LOOKUP_ONLYCONVERTING
);
152 flag_access_control
= old_ac
;
154 if (TYPE_NEEDS_DESTRUCTOR (type
))
156 init
= maybe_build_cleanup (init
);
157 if (init
!= NULL_TREE
)
158 expand_expr (init
, const0_rtx
, VOIDmode
, 0);
162 return DECL_RTL (slot
);
170 /* Find the member. */
171 member
= PTRMEM_CST_MEMBER (exp
);
173 if (TREE_CODE (member
) == FIELD_DECL
)
175 /* Find the offset for the field. */
176 offset
= convert (sizetype
,
177 size_binop (EASY_DIV_EXPR
,
178 DECL_FIELD_BITPOS (member
),
179 size_int (BITS_PER_UNIT
)));
181 /* We offset all pointer to data members by 1 so that we
182 can distinguish between a null pointer to data member
183 and the first data member of a structure. */
184 offset
= size_binop (PLUS_EXPR
, offset
, size_int (1));
186 return expand_expr (cp_convert (type
, offset
), target
, tmode
,
196 expand_ptrmemfunc_cst (exp
, &delta
, &idx
, &pfn
, &delta2
);
198 return expand_expr (build_ptrmemfunc1 (type
, delta
, idx
,
200 target
, tmode
, modifier
);
206 return expand_expr (default_conversion (resolve_offset_ref (exp
)),
207 target
, tmode
, EXPAND_NORMAL
);
211 return DECL_RTL (exp
);
214 expand_throw (TREE_OPERAND (exp
, 0));
220 (NULL_TREE
, TREE_OPERAND (exp
, 0),
221 build_binary_op (MINUS_EXPR
, TREE_OPERAND (exp
, 2),
223 TREE_OPERAND (exp
, 1), 0), target
, tmode
, modifier
);
226 return expand_expr (build_new_1 (exp
), target
, tmode
, modifier
);
231 my_friendly_abort (40);
239 lang_expand_expr
= cplus_expand_expr
;
242 /* If DECL had its rtl moved from where callers expect it
243 to be, fix it up. RESULT is the nominal rtl for the RESULT_DECL,
244 which may be a pseudo instead of a hard register. */
247 fixup_result_decl (decl
, result
)
253 if (REGNO (result
) >= FIRST_PSEUDO_REGISTER
)
255 rtx real_decl_result
;
257 #ifdef FUNCTION_OUTGOING_VALUE
259 = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl
), current_function_decl
);
262 = FUNCTION_VALUE (TREE_TYPE (decl
), current_function_decl
);
264 REG_FUNCTION_VALUE_P (real_decl_result
) = 1;
265 result
= real_decl_result
;
267 store_expr (decl
, result
, 0);
268 emit_insn (gen_rtx (USE
, VOIDmode
, result
));
273 /* Expand this initialization inline and see if it's simple enough that
274 it can be done at compile-time. */
277 extract_aggr_init (decl
, init
)
284 extract_scalar_init (decl
, init
)
287 rtx value
, insns
, insn
;
288 extern struct obstack temporary_obstack
;
291 push_obstacks (&temporary_obstack
, &temporary_obstack
);
293 value
= expand_expr (init
, NULL_RTX
, VOIDmode
, 0);
294 insns
= get_insns ();
296 reg_scan (insns
, max_reg_num (), 0);
297 jump_optimize (insns
, 0, 0, 1);
300 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
304 if (GET_CODE (insn
) == NOTE
)
306 else if (GET_CODE (insn
) != INSN
)
310 if (GET_CODE (r
) != SET
)
316 || (GET_CODE (to
) == SUBREG
&& XEXP (to
, 0) == value
)))
321 switch (GET_CODE (r
))
324 t
= build_int_2 (XEXP (r
, 0), 0);
336 extract_init (decl
, init
)
337 tree decl ATTRIBUTE_UNUSED
, init ATTRIBUTE_UNUSED
;
342 if (IS_AGGR_TYPE (TREE_TYPE (decl
))
343 || TREE_CODE (TREE_TYPE (decl
)) == ARRAY_TYPE
)
344 init
= extract_aggr_init (decl
, init
);
346 init
= extract_scalar_init (decl
, init
);
348 if (init
== NULL_TREE
)
351 DECL_INITIAL (decl
) = init
;
360 tree value1
= NULL_TREE
, value2
= NULL_TREE
, label
;
362 if (start
!= NULL_TREE
&& TREE_TYPE (start
) != NULL_TREE
363 && POINTER_TYPE_P (TREE_TYPE (start
)))
364 error ("pointers are not permitted as case values");
367 pedwarn ("ANSI C++ forbids range expressions in switch statement");
369 if (processing_template_decl
)
371 add_tree (build_min_nt (CASE_LABEL
, start
, end
));
376 value1
= check_cp_case_value (start
);
378 value2
= check_cp_case_value (end
);
380 label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
382 if (value1
!= error_mark_node
383 && value2
!= error_mark_node
)
389 success
= pushcase_range (value1
, value2
, convert_and_check
,
392 success
= pushcase (value1
, convert_and_check
, label
, &duplicate
);
394 success
= pushcase (NULL_TREE
, 0, label
, &duplicate
);
399 error ("case label not within a switch statement");
401 cp_error ("case label `%E' not within a switch statement", start
);
403 error ("default label not within a switch statement");
405 else if (success
== 2)
409 error ("duplicate (or overlapping) case value");
410 cp_error_at ("this is the first entry overlapping that value",
415 cp_error ("duplicate case value `%E'", start
);
416 cp_error_at ("previously used here", duplicate
);
420 error ("multiple default labels in one switch");
421 cp_error_at ("this is the first default label", duplicate
);
424 else if (success
== 3)
425 warning ("case value out of range");
426 else if (success
== 4)
427 warning ("empty range specified");
428 else if (success
== 5)
431 error ("case label within scope of cleanup or variable array");
433 error ("`default' label within scope of cleanup or variable array");
435 cp_error ("case label `%E' within scope of cleanup or variable array", start
);
438 define_case_label ();