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/* Function return value location for Alpha ELF ABI.
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Copyright (C) 2005 Red Hat, Inc.
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This file is part of Red Hat elfutils.
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Red Hat elfutils is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by the
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Free Software Foundation; version 2 of the License.
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Red Hat elfutils is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License along
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with Red Hat elfutils; if not, write to the Free Software Foundation,
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Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
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Red Hat elfutils is an included package of the Open Invention Network.
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An included package of the Open Invention Network is a package for which
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Open Invention Network licensees cross-license their patents. No patent
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license is granted, either expressly or impliedly, by designation as an
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included package. Should you wish to participate in the Open Invention
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Network licensing program, please visit www.openinventionnetwork.com
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<http://www.openinventionnetwork.com>. */
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#define BACKEND alpha_
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#include "libebl_CPU.h"
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static const Dwarf_Op loc_intreg[] =
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{ .atom = DW_OP_reg0 }
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/* $f0, or pair $f0, $f1. */
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static const Dwarf_Op loc_fpreg[] =
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{ .atom = DW_OP_regx, .number = 32 }, { .atom = DW_OP_piece, .number = 4 },
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{ .atom = DW_OP_regx, .number = 33 }, { .atom = DW_OP_piece, .number = 4 },
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#define nloc_fpregpair 4
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/* The return value is a structure and is actually stored in stack space
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passed in a hidden argument by the caller. But, the compiler
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helpfully returns the address of that space in $0. */
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static const Dwarf_Op loc_aggregate[] =
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{ .atom = DW_OP_breg0, .number = 0 }
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#define nloc_aggregate 1
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alpha_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp)
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/* Start with the function's type, and get the DW_AT_type attribute,
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which is the type of the return value. */
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Dwarf_Attribute attr_mem;
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Dwarf_Attribute *attr = dwarf_attr (functypedie, DW_AT_type, &attr_mem);
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/* The function has no return value, like a `void' function in C. */
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Dwarf_Die *typedie = dwarf_formref_die (attr, &die_mem);
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int tag = dwarf_tag (typedie);
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/* Follow typedefs and qualifiers to get to the actual type. */
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while (tag == DW_TAG_typedef
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|| tag == DW_TAG_const_type || tag == DW_TAG_volatile_type
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|| tag == DW_TAG_restrict_type || tag == DW_TAG_mutable_type)
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attr = dwarf_attr (typedie, DW_AT_type, &attr_mem);
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typedie = dwarf_formref_die (attr, &die_mem);
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tag = dwarf_tag (typedie);
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case DW_TAG_subrange_type:
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if (! dwarf_hasattr (typedie, DW_AT_byte_size))
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attr = dwarf_attr (typedie, DW_AT_type, &attr_mem);
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typedie = dwarf_formref_die (attr, &die_mem);
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tag = dwarf_tag (typedie);
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case DW_TAG_base_type:
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case DW_TAG_enumeration_type:
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case DW_TAG_pointer_type:
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case DW_TAG_ptr_to_member_type:
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if (dwarf_formudata (dwarf_attr (typedie, DW_AT_byte_size,
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&attr_mem), &size) != 0)
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if (tag == DW_TAG_pointer_type || tag == DW_TAG_ptr_to_member_type)
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if (tag == DW_TAG_base_type)
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if (dwarf_formudata (dwarf_attr (typedie, DW_AT_encoding,
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&attr_mem), &encoding) != 0)
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if (encoding == DW_ATE_float)
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if (encoding == DW_ATE_complex_float)
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return nloc_fpregpair;
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/* Else fall through. */
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case DW_TAG_structure_type:
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case DW_TAG_class_type:
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case DW_TAG_union_type:
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case DW_TAG_string_type:
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case DW_TAG_array_type:
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*locp = loc_aggregate;
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return nloc_aggregate;
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/* XXX We don't have a good way to return specific errors from ebl calls.
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This value means we do not understand the type, but it is well-formed
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DWARF and might be valid. */
added
removed
backends/alpha_retval.c
