1 /* Default target hook functions.
2 Copyright (C) 2003, 2004 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 2, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to the Free
18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 /* The migration of target macros to target hooks works as follows:
23 1. Create a target hook that uses the existing target macros to
24 implement the same functionality.
26 2. Convert all the MI files to use the hook instead of the macro.
28 3. Repeat for a majority of the remaining target macros. This will
31 4. Tell target maintainers to start migrating.
33 5. Eventually convert the backends to override the hook instead of
34 defining the macros. This will take some time too.
36 6. TBD when, poison the macros. Unmigrated targets will break at
39 Note that we expect steps 1-3 to be done by the people that
40 understand what the MI does with each macro, and step 5 to be done
41 by the target maintainers for their respective targets.
43 Note that steps 1 and 2 don't have to be done together, but no
44 target can override the new hook until step 2 is complete for it.
46 Once the macros are poisoned, we will revert to the old migration
47 rules - migrate the macro, callers, and targets all at once. This
48 comment can thus be removed at that point. */
52 #include "coretypes.h"
63 #include "target-def.h"
67 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
69 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
70 ASM_OUTPUT_EXTERNAL_LIBCALL(asm_out_file, fun);
75 default_cc_modes_compatible (enum machine_mode m1, enum machine_mode m2)
83 default_return_in_memory (tree type,
84 tree fntype ATTRIBUTE_UNUSED)
86 #ifndef RETURN_IN_MEMORY
87 return (TYPE_MODE (type) == BLKmode);
89 return RETURN_IN_MEMORY (type);
94 default_expand_builtin_saveregs (void)
96 error ("__builtin_saveregs not supported by this target");
101 default_fold_builtin (tree t ATTRIBUTE_UNUSED, bool ignore ATTRIBUTE_UNUSED)
107 default_setup_incoming_varargs (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
108 enum machine_mode mode ATTRIBUTE_UNUSED,
109 tree type ATTRIBUTE_UNUSED,
110 int *pretend_arg_size ATTRIBUTE_UNUSED,
111 int second_time ATTRIBUTE_UNUSED)
115 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE. */
118 default_builtin_setjmp_frame_value (void)
120 return virtual_stack_vars_rtx;
123 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false. */
126 hook_bool_CUMULATIVE_ARGS_false (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED)
132 default_pretend_outgoing_varargs_named (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED)
134 return (targetm.calls.setup_incoming_varargs
135 != default_setup_incoming_varargs);
139 default_eh_return_filter_mode (void)
144 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK. */
146 unsigned HOST_WIDE_INT
147 default_shift_truncation_mask (enum machine_mode mode)
149 return SHIFT_COUNT_TRUNCATED ? GET_MODE_BITSIZE (mode) - 1 : 0;
152 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true. */
155 hook_bool_CUMULATIVE_ARGS_true (CUMULATIVE_ARGS * a ATTRIBUTE_UNUSED)
161 /* The generic C++ ABI specifies this is a 64-bit value. */
163 default_cxx_guard_type (void)
165 return long_long_integer_type_node;
169 /* Returns the size of the cookie to use when allocating an array
170 whose elements have the indicated TYPE. Assumes that it is already
171 known that a cookie is needed. */
174 default_cxx_get_cookie_size (tree type)
178 /* We need to allocate an additional max (sizeof (size_t), alignof
179 (true_type)) bytes. */
183 sizetype_size = size_in_bytes (sizetype);
184 type_align = size_int (TYPE_ALIGN_UNIT (type));
185 if (INT_CST_LT_UNSIGNED (type_align, sizetype_size))
186 cookie_size = sizetype_size;
188 cookie_size = type_align;
193 /* Return true if a parameter must be passed by reference. This version
194 of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK. */
197 hook_pass_by_reference_must_pass_in_stack (CUMULATIVE_ARGS *c ATTRIBUTE_UNUSED,
198 enum machine_mode mode ATTRIBUTE_UNUSED, tree type ATTRIBUTE_UNUSED,
199 bool named_arg ATTRIBUTE_UNUSED)
201 return targetm.calls.must_pass_in_stack (mode, type);
204 /* Return true if a parameter follows callee copies conventions. This
205 version of the hook is true for all named arguments. */
208 hook_callee_copies_named (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
209 enum machine_mode mode ATTRIBUTE_UNUSED,
210 tree type ATTRIBUTE_UNUSED, bool named)
215 /* Emit any directives required to unwind this instruction. */
218 default_unwind_emit (FILE * stream ATTRIBUTE_UNUSED,
219 rtx insn ATTRIBUTE_UNUSED)
221 /* Should never happen. */
225 /* True if MODE is valid for the target. By "valid", we mean able to
226 be manipulated in non-trivial ways. In particular, this means all
227 the arithmetic is supported.
229 By default we guess this means that any C type is supported. If
230 we can't map the mode back to a type that would be available in C,
231 then reject it. Special case, here, is the double-word arithmetic
232 supported by optabs.c. */
235 default_scalar_mode_supported_p (enum machine_mode mode)
237 int precision = GET_MODE_PRECISION (mode);
239 switch (GET_MODE_CLASS (mode))
241 case MODE_PARTIAL_INT:
243 if (precision == CHAR_TYPE_SIZE)
245 if (precision == SHORT_TYPE_SIZE)
247 if (precision == INT_TYPE_SIZE)
249 if (precision == LONG_TYPE_SIZE)
251 if (precision == LONG_LONG_TYPE_SIZE)
253 if (precision == 2 * BITS_PER_WORD)
258 if (precision == FLOAT_TYPE_SIZE)
260 if (precision == DOUBLE_TYPE_SIZE)
262 if (precision == LONG_DOUBLE_TYPE_SIZE)
272 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
273 CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
274 enum machine_mode mode ATTRIBUTE_UNUSED,
275 tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
281 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
282 CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
283 enum machine_mode mode ATTRIBUTE_UNUSED,
284 tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)