125b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* Function return value location for Linux/PPC64 ABI. 225b3c049e70834cf33790a28643ab058b507b35cBen Cheng Copyright (C) 2005-2010 Red Hat, Inc. 325b3c049e70834cf33790a28643ab058b507b35cBen Cheng This file is part of Red Hat elfutils. 425b3c049e70834cf33790a28643ab058b507b35cBen Cheng 525b3c049e70834cf33790a28643ab058b507b35cBen Cheng Red Hat elfutils is free software; you can redistribute it and/or modify 625b3c049e70834cf33790a28643ab058b507b35cBen Cheng it under the terms of the GNU General Public License as published by the 725b3c049e70834cf33790a28643ab058b507b35cBen Cheng Free Software Foundation; version 2 of the License. 825b3c049e70834cf33790a28643ab058b507b35cBen Cheng 925b3c049e70834cf33790a28643ab058b507b35cBen Cheng Red Hat elfutils is distributed in the hope that it will be useful, but 1025b3c049e70834cf33790a28643ab058b507b35cBen Cheng WITHOUT ANY WARRANTY; without even the implied warranty of 1125b3c049e70834cf33790a28643ab058b507b35cBen Cheng MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 1225b3c049e70834cf33790a28643ab058b507b35cBen Cheng General Public License for more details. 1325b3c049e70834cf33790a28643ab058b507b35cBen Cheng 1425b3c049e70834cf33790a28643ab058b507b35cBen Cheng You should have received a copy of the GNU General Public License along 1525b3c049e70834cf33790a28643ab058b507b35cBen Cheng with Red Hat elfutils; if not, write to the Free Software Foundation, 1625b3c049e70834cf33790a28643ab058b507b35cBen Cheng Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 1725b3c049e70834cf33790a28643ab058b507b35cBen Cheng 1825b3c049e70834cf33790a28643ab058b507b35cBen Cheng Red Hat elfutils is an included package of the Open Invention Network. 1925b3c049e70834cf33790a28643ab058b507b35cBen Cheng An included package of the Open Invention Network is a package for which 2025b3c049e70834cf33790a28643ab058b507b35cBen Cheng Open Invention Network licensees cross-license their patents. No patent 2125b3c049e70834cf33790a28643ab058b507b35cBen Cheng license is granted, either expressly or impliedly, by designation as an 2225b3c049e70834cf33790a28643ab058b507b35cBen Cheng included package. Should you wish to participate in the Open Invention 2325b3c049e70834cf33790a28643ab058b507b35cBen Cheng Network licensing program, please visit www.openinventionnetwork.com 2425b3c049e70834cf33790a28643ab058b507b35cBen Cheng <http://www.openinventionnetwork.com>. */ 2525b3c049e70834cf33790a28643ab058b507b35cBen Cheng 2625b3c049e70834cf33790a28643ab058b507b35cBen Cheng#ifdef HAVE_CONFIG_H 2725b3c049e70834cf33790a28643ab058b507b35cBen Cheng# include <config.h> 2825b3c049e70834cf33790a28643ab058b507b35cBen Cheng#endif 2925b3c049e70834cf33790a28643ab058b507b35cBen Cheng 3025b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <assert.h> 3125b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <dwarf.h> 3225b3c049e70834cf33790a28643ab058b507b35cBen Cheng 3325b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define BACKEND ppc64_ 3425b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include "libebl_CPU.h" 3525b3c049e70834cf33790a28643ab058b507b35cBen Cheng 3625b3c049e70834cf33790a28643ab058b507b35cBen Cheng 3725b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* r3. */ 3825b3c049e70834cf33790a28643ab058b507b35cBen Chengstatic const Dwarf_Op loc_intreg[] = 3925b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 4025b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_reg3 } 4125b3c049e70834cf33790a28643ab058b507b35cBen Cheng }; 4225b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define nloc_intreg 1 4325b3c049e70834cf33790a28643ab058b507b35cBen Cheng 4425b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* f1, or f1:f2, or f1:f4. */ 4525b3c049e70834cf33790a28643ab058b507b35cBen Chengstatic const Dwarf_Op loc_fpreg[] = 4625b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 4725b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_regx, .number = 33 }, { .atom = DW_OP_piece, .number = 8 }, 4825b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_regx, .number = 34 }, { .atom = DW_OP_piece, .number = 8 }, 4925b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_regx, .number = 35 }, { .atom = DW_OP_piece, .number = 8 }, 5025b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_regx, .number = 36 }, { .atom = DW_OP_piece, .number = 8 }, 5125b3c049e70834cf33790a28643ab058b507b35cBen Cheng }; 5225b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define nloc_fpreg 1 5325b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define nloc_fp2regs 4 5425b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define nloc_fp4regs 8 5525b3c049e70834cf33790a28643ab058b507b35cBen Cheng 5625b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* vr2. */ 5725b3c049e70834cf33790a28643ab058b507b35cBen Chengstatic const Dwarf_Op loc_vmxreg[] = 5825b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 5925b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_regx, .number = 1124 + 2 } 6025b3c049e70834cf33790a28643ab058b507b35cBen Cheng }; 6125b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define nloc_vmxreg 1 6225b3c049e70834cf33790a28643ab058b507b35cBen Cheng 6325b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* The return value is a structure and is actually stored in stack space 6425b3c049e70834cf33790a28643ab058b507b35cBen Cheng passed in a hidden argument by the caller. But, the compiler 6525b3c049e70834cf33790a28643ab058b507b35cBen Cheng helpfully returns the address of that space in r3. */ 6625b3c049e70834cf33790a28643ab058b507b35cBen Chengstatic const Dwarf_Op loc_aggregate[] = 6725b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 6825b3c049e70834cf33790a28643ab058b507b35cBen Cheng { .atom = DW_OP_breg3, .number = 0 } 6925b3c049e70834cf33790a28643ab058b507b35cBen Cheng }; 7025b3c049e70834cf33790a28643ab058b507b35cBen Cheng#define nloc_aggregate 1 7125b3c049e70834cf33790a28643ab058b507b35cBen Cheng 7225b3c049e70834cf33790a28643ab058b507b35cBen Chengint 7325b3c049e70834cf33790a28643ab058b507b35cBen Chengppc64_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) 7425b3c049e70834cf33790a28643ab058b507b35cBen Cheng{ 7525b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Start with the function's type, and get the DW_AT_type attribute, 7625b3c049e70834cf33790a28643ab058b507b35cBen Cheng which is the type of the return value. */ 7725b3c049e70834cf33790a28643ab058b507b35cBen Cheng 7825b3c049e70834cf33790a28643ab058b507b35cBen Cheng Dwarf_Attribute attr_mem; 7925b3c049e70834cf33790a28643ab058b507b35cBen Cheng Dwarf_Attribute *attr = dwarf_attr_integrate (functypedie, DW_AT_type, 8025b3c049e70834cf33790a28643ab058b507b35cBen Cheng &attr_mem); 8125b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (attr == NULL) 8225b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* The function has no return value, like a `void' function in C. */ 8325b3c049e70834cf33790a28643ab058b507b35cBen Cheng return 0; 8425b3c049e70834cf33790a28643ab058b507b35cBen Cheng 8525b3c049e70834cf33790a28643ab058b507b35cBen Cheng Dwarf_Die die_mem; 8625b3c049e70834cf33790a28643ab058b507b35cBen Cheng Dwarf_Die *typedie = dwarf_formref_die (attr, &die_mem); 8725b3c049e70834cf33790a28643ab058b507b35cBen Cheng int tag = dwarf_tag (typedie); 8825b3c049e70834cf33790a28643ab058b507b35cBen Cheng 8925b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Follow typedefs and qualifiers to get to the actual type. */ 9025b3c049e70834cf33790a28643ab058b507b35cBen Cheng while (tag == DW_TAG_typedef 9125b3c049e70834cf33790a28643ab058b507b35cBen Cheng || tag == DW_TAG_const_type || tag == DW_TAG_volatile_type 9225b3c049e70834cf33790a28643ab058b507b35cBen Cheng || tag == DW_TAG_restrict_type || tag == DW_TAG_mutable_type) 9325b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 9425b3c049e70834cf33790a28643ab058b507b35cBen Cheng attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem); 9525b3c049e70834cf33790a28643ab058b507b35cBen Cheng typedie = dwarf_formref_die (attr, &die_mem); 9625b3c049e70834cf33790a28643ab058b507b35cBen Cheng tag = dwarf_tag (typedie); 9725b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 9825b3c049e70834cf33790a28643ab058b507b35cBen Cheng 9925b3c049e70834cf33790a28643ab058b507b35cBen Cheng Dwarf_Word size; 10025b3c049e70834cf33790a28643ab058b507b35cBen Cheng switch (tag) 10125b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 10225b3c049e70834cf33790a28643ab058b507b35cBen Cheng case -1: 10325b3c049e70834cf33790a28643ab058b507b35cBen Cheng return -1; 10425b3c049e70834cf33790a28643ab058b507b35cBen Cheng 10525b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_subrange_type: 10625b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (! dwarf_hasattr_integrate (typedie, DW_AT_byte_size)) 10725b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 10825b3c049e70834cf33790a28643ab058b507b35cBen Cheng attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem); 10925b3c049e70834cf33790a28643ab058b507b35cBen Cheng typedie = dwarf_formref_die (attr, &die_mem); 11025b3c049e70834cf33790a28643ab058b507b35cBen Cheng tag = dwarf_tag (typedie); 11125b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 11225b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Fall through. */ 11325b3c049e70834cf33790a28643ab058b507b35cBen Cheng 11425b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_base_type: 11525b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_enumeration_type: 11625b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_pointer_type: 11725b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_ptr_to_member_type: 11825b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_byte_size, 11925b3c049e70834cf33790a28643ab058b507b35cBen Cheng &attr_mem), &size) != 0) 12025b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 12125b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (tag == DW_TAG_pointer_type || tag == DW_TAG_ptr_to_member_type) 12225b3c049e70834cf33790a28643ab058b507b35cBen Cheng size = 8; 12325b3c049e70834cf33790a28643ab058b507b35cBen Cheng else 12425b3c049e70834cf33790a28643ab058b507b35cBen Cheng return -1; 12525b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 12625b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (tag == DW_TAG_base_type) 12725b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 12825b3c049e70834cf33790a28643ab058b507b35cBen Cheng Dwarf_Word encoding; 12925b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_encoding, 13025b3c049e70834cf33790a28643ab058b507b35cBen Cheng &attr_mem), 13125b3c049e70834cf33790a28643ab058b507b35cBen Cheng &encoding) != 0) 13225b3c049e70834cf33790a28643ab058b507b35cBen Cheng return -1; 13325b3c049e70834cf33790a28643ab058b507b35cBen Cheng 13425b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (encoding == DW_ATE_float || encoding == DW_ATE_complex_float) 13525b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 13625b3c049e70834cf33790a28643ab058b507b35cBen Cheng *locp = loc_fpreg; 13725b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (size <= 8) 13825b3c049e70834cf33790a28643ab058b507b35cBen Cheng return nloc_fpreg; 13925b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (size <= 16) 14025b3c049e70834cf33790a28643ab058b507b35cBen Cheng return nloc_fp2regs; 14125b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (size <= 32) 14225b3c049e70834cf33790a28643ab058b507b35cBen Cheng return nloc_fp4regs; 14325b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 14425b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 14525b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (size <= 8) 14625b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 14725b3c049e70834cf33790a28643ab058b507b35cBen Cheng intreg: 14825b3c049e70834cf33790a28643ab058b507b35cBen Cheng *locp = loc_intreg; 14925b3c049e70834cf33790a28643ab058b507b35cBen Cheng return nloc_intreg; 15025b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 15125b3c049e70834cf33790a28643ab058b507b35cBen Cheng 15225b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Else fall through. */ 15325b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_structure_type: 15425b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_class_type: 15525b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_union_type: 15625b3c049e70834cf33790a28643ab058b507b35cBen Cheng aggregate: 15725b3c049e70834cf33790a28643ab058b507b35cBen Cheng *locp = loc_aggregate; 15825b3c049e70834cf33790a28643ab058b507b35cBen Cheng return nloc_aggregate; 15925b3c049e70834cf33790a28643ab058b507b35cBen Cheng 16025b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_array_type: 16125b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 16225b3c049e70834cf33790a28643ab058b507b35cBen Cheng bool is_vector; 16325b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (dwarf_formflag (dwarf_attr_integrate (typedie, DW_AT_GNU_vector, 16425b3c049e70834cf33790a28643ab058b507b35cBen Cheng &attr_mem), &is_vector) == 0 16525b3c049e70834cf33790a28643ab058b507b35cBen Cheng && is_vector) 16625b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 16725b3c049e70834cf33790a28643ab058b507b35cBen Cheng *locp = loc_vmxreg; 16825b3c049e70834cf33790a28643ab058b507b35cBen Cheng return nloc_vmxreg; 16925b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 17025b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 17125b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Fall through. */ 17225b3c049e70834cf33790a28643ab058b507b35cBen Cheng 17325b3c049e70834cf33790a28643ab058b507b35cBen Cheng case DW_TAG_string_type: 17425b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (dwarf_aggregate_size (typedie, &size) == 0 && size <= 8) 17525b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 17625b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (tag == DW_TAG_array_type) 17725b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 17825b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Check if it's a character array. */ 17925b3c049e70834cf33790a28643ab058b507b35cBen Cheng attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem); 18025b3c049e70834cf33790a28643ab058b507b35cBen Cheng typedie = dwarf_formref_die (attr, &die_mem); 18125b3c049e70834cf33790a28643ab058b507b35cBen Cheng tag = dwarf_tag (typedie); 18225b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (tag != DW_TAG_base_type) 18325b3c049e70834cf33790a28643ab058b507b35cBen Cheng goto aggregate; 18425b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (dwarf_formudata (dwarf_attr_integrate (typedie, 18525b3c049e70834cf33790a28643ab058b507b35cBen Cheng DW_AT_byte_size, 18625b3c049e70834cf33790a28643ab058b507b35cBen Cheng &attr_mem), 18725b3c049e70834cf33790a28643ab058b507b35cBen Cheng &size) != 0) 18825b3c049e70834cf33790a28643ab058b507b35cBen Cheng return -1; 18925b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (size != 1) 19025b3c049e70834cf33790a28643ab058b507b35cBen Cheng goto aggregate; 19125b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 19225b3c049e70834cf33790a28643ab058b507b35cBen Cheng goto intreg; 19325b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 19425b3c049e70834cf33790a28643ab058b507b35cBen Cheng goto aggregate; 19525b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 19625b3c049e70834cf33790a28643ab058b507b35cBen Cheng 19725b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* XXX We don't have a good way to return specific errors from ebl calls. 19825b3c049e70834cf33790a28643ab058b507b35cBen Cheng This value means we do not understand the type, but it is well-formed 19925b3c049e70834cf33790a28643ab058b507b35cBen Cheng DWARF and might be valid. */ 20025b3c049e70834cf33790a28643ab058b507b35cBen Cheng return -2; 20125b3c049e70834cf33790a28643ab058b507b35cBen Cheng} 202