1 /* Function return value location for SPARC.
2 Copyright (C) 2006-2010 Red Hat, Inc.
3 This file is part of elfutils.
5 This file is free software; you can redistribute it and/or modify
6 it under the terms of either
8 * the GNU Lesser General Public License as published by the Free
9 Software Foundation; either version 3 of the License, or (at
10 your option) any later version
14 * the GNU General Public License as published by the Free
15 Software Foundation; either version 2 of the License, or (at
16 your option) any later version
18 or both in parallel, as here.
20 elfutils is distributed in the hope that it will be useful, but
21 WITHOUT ANY WARRANTY; without even the implied warranty of
22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 General Public License for more details.
25 You should have received copies of the GNU General Public License and
26 the GNU Lesser General Public License along with this program. If
27 not, see <http://www.gnu.org/licenses/>. */
36 #define BACKEND sparc_
37 #include "libebl_CPU.h"
40 /* %o0, or pair %o0, %o1. */
41 static const Dwarf_Op loc_intreg[] =
43 { .atom = DW_OP_reg8 }, { .atom = DW_OP_piece, .number = 4 },
44 { .atom = DW_OP_reg9 }, { .atom = DW_OP_piece, .number = 4 },
47 #define nloc_intregpair 4
49 /* %f0 or pair %f0, %f1, or quad %f0..%f3. */
50 static const Dwarf_Op loc_fpreg[] =
52 { .atom = DW_OP_regx, .number = 32 }, { .atom = DW_OP_piece, .number = 4 },
53 { .atom = DW_OP_regx, .number = 33 }, { .atom = DW_OP_piece, .number = 4 },
54 { .atom = DW_OP_regx, .number = 34 }, { .atom = DW_OP_piece, .number = 4 },
55 { .atom = DW_OP_regx, .number = 35 }, { .atom = DW_OP_piece, .number = 4 },
58 #define nloc_fpregpair 4
59 #define nloc_fpregquad 8
61 /* The return value is a structure and is actually stored in stack space
62 passed in a hidden argument by the caller. But, the compiler
63 helpfully returns the address of that space in %o0. */
64 static const Dwarf_Op loc_aggregate[] =
66 { .atom = DW_OP_breg8, .number = 0 }
68 #define nloc_aggregate 1
71 sparc_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp)
73 /* Start with the function's type, and get the DW_AT_type attribute,
74 which is the type of the return value. */
76 Dwarf_Attribute attr_mem;
77 Dwarf_Attribute *attr = dwarf_attr_integrate (functypedie, DW_AT_type,
80 /* The function has no return value, like a `void' function in C. */
84 Dwarf_Die *typedie = dwarf_formref_die (attr, &die_mem);
85 int tag = dwarf_tag (typedie);
87 /* Follow typedefs and qualifiers to get to the actual type. */
88 while (tag == DW_TAG_typedef
89 || tag == DW_TAG_const_type || tag == DW_TAG_volatile_type
90 || tag == DW_TAG_restrict_type || tag == DW_TAG_mutable_type)
92 attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem);
93 typedie = dwarf_formref_die (attr, &die_mem);
94 tag = dwarf_tag (typedie);
103 case DW_TAG_subrange_type:
104 if (! dwarf_hasattr_integrate (typedie, DW_AT_byte_size))
106 attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem);
107 typedie = dwarf_formref_die (attr, &die_mem);
108 tag = dwarf_tag (typedie);
112 case DW_TAG_base_type:
113 case DW_TAG_enumeration_type:
114 case DW_TAG_pointer_type:
115 case DW_TAG_ptr_to_member_type:
116 if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_byte_size,
117 &attr_mem), &size) != 0)
121 if ((tag == DW_TAG_pointer_type || tag == DW_TAG_ptr_to_member_type)
122 && dwarf_diecu (typedie, &cudie, &asize, NULL) != NULL)
127 if (tag == DW_TAG_base_type)
130 if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_encoding,
134 if (encoding == DW_ATE_float)
140 return nloc_fpregpair;
142 return nloc_fpregquad;
149 return size <= 4 ? nloc_intreg : nloc_intregpair;
153 *locp = loc_aggregate;
154 return nloc_aggregate;
156 case DW_TAG_structure_type:
157 case DW_TAG_class_type:
158 case DW_TAG_union_type:
159 case DW_TAG_array_type:
160 if (dwarf_aggregate_size (typedie, &size) == 0
161 && size > 0 && size <= 8)
166 /* XXX We don't have a good way to return specific errors from ebl calls.
167 This value means we do not understand the type, but it is well-formed
168 DWARF and might be valid. */