1 /* Declarations and data types for RTL call insn generation.
2 Copyright (C) 2013-2023 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
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 3, or (at your option) any later
9 version.
10
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
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #ifndef GCC_CALLS_H
21 #define GCC_CALLS_H
22
23 /* Describes a function argument.
24
25 Each argument conceptually has a gimple-level type. Usually this type
26 is available directly as a tree via the TYPE field, but when calling
27 libgcc support functions it might instead be inferred from a mode,
28 in which case the type isn't available directly.
29
30 This gimple-level type might go through promotion before being passed to
31 the target function. Depending on the context, the MODE field is either
32 the mode of the gimple-level type (whether explicitly given or not)
33 or the mode after promotion has been performed. */
34 class function_arg_info
35 {
36 public:
37 function_arg_info ()
38 : type (NULL_TREE), mode (VOIDmode), named (false),
39 pass_by_reference (false)
40 {}
41
42 /* Initialize an argument of mode MODE, either before or after promotion. */
43 function_arg_info (machine_mode mode, bool named)
44 : type (NULL_TREE), mode (mode), named (named), pass_by_reference (false)
45 {}
46
47 /* Initialize an unpromoted argument of type TYPE. */
48 function_arg_info (tree type, bool named)
49 : type (type), mode (TYPE_MODE (type)), named (named),
50 pass_by_reference (false)
51 {}
52
53 /* Initialize an argument with explicit properties. */
54 function_arg_info (tree type, machine_mode mode, bool named)
55 : type (type), mode (mode), named (named), pass_by_reference (false)
56 {}
57
58 /* Return true if the gimple-level type is an aggregate. */
59 bool aggregate_type_p () const { return type && AGGREGATE_TYPE_P (type); }
60
61 /* Return the size of the gimple-level type, or -1 if the size is
62 variable or otherwise not representable as a poly_int64.
63
64 Use this function when MODE is the mode of the type before promotion,
65 or in any context if the target never promotes function arguments. */
66 poly_int64 type_size_in_bytes () const
67 {
68 if (type)
69 return int_size_in_bytes (type);
70 return GET_MODE_SIZE (mode);
71 }
72
73 /* Return the size of the argument after promotion, or -1 if the size
74 is variable or otherwise not representable as a poly_int64.
75
76 Use this function when MODE is the mode of the type after promotion. */
77 poly_int64 promoted_size_in_bytes () const
78 {
79 if (mode == BLKmode)
80 return int_size_in_bytes (type);
81 return GET_MODE_SIZE (mode);
82 }
83
84 /* True if the argument represents the end of the argument list,
85 as returned by end_marker (). */
86 bool end_marker_p () const { return mode == VOIDmode; }
87
88 /* Return a function_arg_info that represents the end of the
89 argument list. */
90 static function_arg_info end_marker ()
91 {
92 return function_arg_info (void_type_node, /*named=*/true);
93 }
94
95 /* The type of the argument, or null if not known (which is true for
96 libgcc support functions). */
97 tree type;
98
99 /* The mode of the argument. Depending on context, this might be
100 the mode of the argument type or the mode after promotion. */
101 machine_mode mode;
102
103 /* True if the argument is treated as a named argument, false if it is
104 treated as an unnamed variadic argument (i.e. one passed through
105 "..."). See also TARGET_STRICT_ARGUMENT_NAMING. */
106 unsigned int named : 1;
107
108 /* True if we have decided to pass the argument by reference, in which case
109 the function_arg_info describes a pointer to the original argument. */
110 unsigned int pass_by_reference : 1;
111 };
112
113 extern int flags_from_decl_or_type (const_tree);
114 extern int call_expr_flags (const_tree);
115 extern int setjmp_call_p (const_tree);
116 extern bool gimple_maybe_alloca_call_p (const gimple *);
117 extern bool gimple_alloca_call_p (const gimple *);
118 extern bool alloca_call_p (const_tree);
119 extern bool must_pass_in_stack_var_size (const function_arg_info &);
120 extern bool must_pass_in_stack_var_size_or_pad (const function_arg_info &);
121 extern bool must_pass_va_arg_in_stack (tree);
122 extern rtx prepare_call_address (tree, rtx, rtx, rtx *, int, int);
123 extern bool shift_return_value (machine_mode, bool, rtx);
124 extern rtx expand_call (tree, rtx, int);
125 extern void fixup_tail_calls (void);
126
127 extern bool pass_by_reference (CUMULATIVE_ARGS *, function_arg_info);
128 extern bool pass_va_arg_by_reference (tree);
129 extern bool apply_pass_by_reference_rules (CUMULATIVE_ARGS *,
130 function_arg_info &);
131 extern bool reference_callee_copied (CUMULATIVE_ARGS *,
132 const function_arg_info &);
133 extern void maybe_complain_about_tail_call (tree, const char *);
134
135 extern rtx rtx_for_static_chain (const_tree, bool);
136 extern bool cxx17_empty_base_field_p (const_tree);
137
138 #endif // GCC_CALLS_H