4277 lines
129 KiB
C++
4277 lines
129 KiB
C++
// arm.cc -- arm target support for gold.
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// Copyright 2009 Free Software Foundation, Inc.
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// Written by Doug Kwan <dougkwan@google.com> based on the i386 code
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// by Ian Lance Taylor <iant@google.com>.
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// This file also contains borrowed and adapted code from
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// bfd/elf32-arm.c.
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// This file is part of gold.
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// This program 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
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// the Free Software Foundation; either version 3 of the License, or
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// (at your option) any later version.
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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// MA 02110-1301, USA.
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#include "gold.h"
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#include <cstring>
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#include <limits>
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#include <cstdio>
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#include <string>
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#include <algorithm>
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#include "elfcpp.h"
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#include "parameters.h"
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#include "reloc.h"
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#include "arm.h"
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#include "object.h"
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#include "symtab.h"
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#include "layout.h"
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#include "output.h"
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#include "copy-relocs.h"
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#include "target.h"
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#include "target-reloc.h"
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#include "target-select.h"
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#include "tls.h"
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#include "defstd.h"
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#include "gc.h"
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namespace
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{
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using namespace gold;
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template<bool big_endian>
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class Output_data_plt_arm;
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template<bool big_endian>
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class Stub_table;
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template<bool big_endian>
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class Arm_input_section;
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template<bool big_endian>
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class Arm_output_section;
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template<bool big_endian>
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class Arm_relobj;
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template<bool big_endian>
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class Target_arm;
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// For convenience.
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typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address;
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// Maximum branch offsets for ARM, THUMB and THUMB2.
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const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8);
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const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8);
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const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4);
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const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4);
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const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4);
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const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
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// The arm target class.
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//
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// This is a very simple port of gold for ARM-EABI. It is intended for
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// supporting Android only for the time being. Only these relocation types
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// are supported.
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//
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// R_ARM_NONE
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// R_ARM_ABS32
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// R_ARM_ABS32_NOI
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// R_ARM_ABS16
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// R_ARM_ABS12
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// R_ARM_ABS8
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// R_ARM_THM_ABS5
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// R_ARM_BASE_ABS
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// R_ARM_REL32
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// R_ARM_THM_CALL
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// R_ARM_COPY
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// R_ARM_GLOB_DAT
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// R_ARM_BASE_PREL
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// R_ARM_JUMP_SLOT
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// R_ARM_RELATIVE
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// R_ARM_GOTOFF32
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// R_ARM_GOT_BREL
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// R_ARM_GOT_PREL
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// R_ARM_PLT32
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// R_ARM_CALL
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// R_ARM_JUMP24
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// R_ARM_TARGET1
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// R_ARM_PREL31
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// R_ARM_ABS8
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// R_ARM_MOVW_ABS_NC
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// R_ARM_MOVT_ABS
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// R_ARM_THM_MOVW_ABS_NC
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// R_ARM_THM_MOVT_ABS
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// R_ARM_MOVW_PREL_NC
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// R_ARM_MOVT_PREL
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// R_ARM_THM_MOVW_PREL_NC
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// R_ARM_THM_MOVT_PREL
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//
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// TODOs:
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// - Generate various branch stubs.
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// - Support interworking.
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// - Define section symbols __exidx_start and __exidx_stop.
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// - Support more relocation types as needed.
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// - Make PLTs more flexible for different architecture features like
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// Thumb-2 and BE8.
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// There are probably a lot more.
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// Instruction template class. This class is similar to the insn_sequence
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// struct in bfd/elf32-arm.c.
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class Insn_template
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{
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public:
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// Types of instruction templates.
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enum Type
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{
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THUMB16_TYPE = 1,
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THUMB32_TYPE,
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ARM_TYPE,
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DATA_TYPE
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};
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// Factory methods to create instrunction templates in different formats.
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static const Insn_template
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thumb16_insn(uint32_t data)
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{ return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); }
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// A bit of a hack. A Thumb conditional branch, in which the proper
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// condition is inserted when we build the stub.
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static const Insn_template
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thumb16_bcond_insn(uint32_t data)
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{ return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 1); }
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static const Insn_template
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thumb32_insn(uint32_t data)
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{ return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); }
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static const Insn_template
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thumb32_b_insn(uint32_t data, int reloc_addend)
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{
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return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24,
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reloc_addend);
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}
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static const Insn_template
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arm_insn(uint32_t data)
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{ return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); }
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static const Insn_template
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arm_rel_insn(unsigned data, int reloc_addend)
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{ return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); }
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static const Insn_template
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data_word(unsigned data, unsigned int r_type, int reloc_addend)
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{ return Insn_template(data, DATA_TYPE, r_type, reloc_addend); }
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// Accessors. This class is used for read-only objects so no modifiers
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// are provided.
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uint32_t
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data() const
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{ return this->data_; }
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// Return the instruction sequence type of this.
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Type
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type() const
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{ return this->type_; }
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// Return the ARM relocation type of this.
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unsigned int
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r_type() const
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{ return this->r_type_; }
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int32_t
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reloc_addend() const
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{ return this->reloc_addend_; }
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// Return size of instrunction template in bytes.
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size_t
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size() const;
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// Return byte-alignment of instrunction template.
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unsigned
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alignment() const;
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private:
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// We make the constructor private to ensure that only the factory
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// methods are used.
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inline
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Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend)
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: data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend)
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{ }
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// Instruction specific data. This is used to store information like
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// some of the instruction bits.
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uint32_t data_;
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// Instruction template type.
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Type type_;
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// Relocation type if there is a relocation or R_ARM_NONE otherwise.
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unsigned int r_type_;
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// Relocation addend.
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int32_t reloc_addend_;
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};
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// Macro for generating code to stub types. One entry per long/short
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// branch stub
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#define DEF_STUBS \
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DEF_STUB(long_branch_any_any) \
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DEF_STUB(long_branch_v4t_arm_thumb) \
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DEF_STUB(long_branch_thumb_only) \
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DEF_STUB(long_branch_v4t_thumb_thumb) \
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DEF_STUB(long_branch_v4t_thumb_arm) \
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DEF_STUB(short_branch_v4t_thumb_arm) \
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DEF_STUB(long_branch_any_arm_pic) \
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DEF_STUB(long_branch_any_thumb_pic) \
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DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
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DEF_STUB(long_branch_v4t_arm_thumb_pic) \
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DEF_STUB(long_branch_v4t_thumb_arm_pic) \
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DEF_STUB(long_branch_thumb_only_pic) \
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DEF_STUB(a8_veneer_b_cond) \
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DEF_STUB(a8_veneer_b) \
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DEF_STUB(a8_veneer_bl) \
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DEF_STUB(a8_veneer_blx)
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// Stub types.
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#define DEF_STUB(x) arm_stub_##x,
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typedef enum
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{
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arm_stub_none,
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DEF_STUBS
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// First reloc stub type.
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arm_stub_reloc_first = arm_stub_long_branch_any_any,
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// Last reloc stub type.
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arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic,
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// First Cortex-A8 stub type.
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arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond,
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// Last Cortex-A8 stub type.
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arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
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// Last stub type.
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arm_stub_type_last = arm_stub_a8_veneer_blx
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} Stub_type;
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#undef DEF_STUB
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// Stub template class. Templates are meant to be read-only objects.
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// A stub template for a stub type contains all read-only attributes
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// common to all stubs of the same type.
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class Stub_template
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{
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public:
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Stub_template(Stub_type, const Insn_template*, size_t);
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~Stub_template()
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{ }
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// Return stub type.
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Stub_type
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type() const
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{ return this->type_; }
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// Return an array of instruction templates.
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const Insn_template*
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insns() const
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{ return this->insns_; }
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// Return size of template in number of instructions.
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size_t
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insn_count() const
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{ return this->insn_count_; }
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// Return size of template in bytes.
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size_t
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size() const
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{ return this->size_; }
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// Return alignment of the stub template.
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unsigned
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alignment() const
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{ return this->alignment_; }
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// Return whether entry point is in thumb mode.
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bool
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entry_in_thumb_mode() const
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{ return this->entry_in_thumb_mode_; }
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// Return number of relocations in this template.
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size_t
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reloc_count() const
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{ return this->relocs_.size(); }
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// Return index of the I-th instruction with relocation.
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size_t
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reloc_insn_index(size_t i) const
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{
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gold_assert(i < this->relocs_.size());
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return this->relocs_[i].first;
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}
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// Return the offset of the I-th instruction with relocation from the
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// beginning of the stub.
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section_size_type
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reloc_offset(size_t i) const
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{
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gold_assert(i < this->relocs_.size());
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return this->relocs_[i].second;
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}
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private:
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// This contains information about an instruction template with a relocation
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// and its offset from start of stub.
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typedef std::pair<size_t, section_size_type> Reloc;
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// A Stub_template may not be copied. We want to share templates as much
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// as possible.
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Stub_template(const Stub_template&);
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Stub_template& operator=(const Stub_template&);
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// Stub type.
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Stub_type type_;
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// Points to an array of Insn_templates.
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const Insn_template* insns_;
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// Number of Insn_templates in insns_[].
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size_t insn_count_;
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// Size of templated instructions in bytes.
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size_t size_;
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// Alignment of templated instructions.
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unsigned alignment_;
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// Flag to indicate if entry is in thumb mode.
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bool entry_in_thumb_mode_;
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// A table of reloc instruction indices and offsets. We can find these by
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// looking at the instruction templates but we pre-compute and then stash
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// them here for speed.
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std::vector<Reloc> relocs_;
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};
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//
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// A class for code stubs. This is a base class for different type of
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// stubs used in the ARM target.
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//
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class Stub
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{
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private:
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static const section_offset_type invalid_offset =
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static_cast<section_offset_type>(-1);
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public:
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Stub(const Stub_template* stub_template)
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: stub_template_(stub_template), offset_(invalid_offset)
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{ }
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virtual
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~Stub()
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{ }
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// Return the stub template.
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const Stub_template*
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stub_template() const
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{ return this->stub_template_; }
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// Return offset of code stub from beginning of its containing stub table.
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section_offset_type
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offset() const
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{
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gold_assert(this->offset_ != invalid_offset);
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return this->offset_;
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}
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// Set offset of code stub from beginning of its containing stub table.
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void
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set_offset(section_offset_type offset)
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{ this->offset_ = offset; }
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// Return the relocation target address of the i-th relocation in the
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// stub. This must be defined in a child class.
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Arm_address
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reloc_target(size_t i)
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{ return this->do_reloc_target(i); }
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// Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
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void
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write(unsigned char* view, section_size_type view_size, bool big_endian)
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{ this->do_write(view, view_size, big_endian); }
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protected:
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// This must be defined in the child class.
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virtual Arm_address
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do_reloc_target(size_t) = 0;
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// This must be defined in the child class.
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virtual void
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do_write(unsigned char*, section_size_type, bool) = 0;
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private:
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// Its template.
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const Stub_template* stub_template_;
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// Offset within the section of containing this stub.
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section_offset_type offset_;
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};
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// Reloc stub class. These are stubs we use to fix up relocation because
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// of limited branch ranges.
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class Reloc_stub : public Stub
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{
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public:
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static const unsigned int invalid_index = static_cast<unsigned int>(-1);
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// We assume we never jump to this address.
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static const Arm_address invalid_address = static_cast<Arm_address>(-1);
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// Return destination address.
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Arm_address
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destination_address() const
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{
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gold_assert(this->destination_address_ != this->invalid_address);
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return this->destination_address_;
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}
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// Set destination address.
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void
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set_destination_address(Arm_address address)
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{
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gold_assert(address != this->invalid_address);
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this->destination_address_ = address;
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}
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// Reset destination address.
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void
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reset_destination_address()
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{ this->destination_address_ = this->invalid_address; }
|
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|
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// Determine stub type for a branch of a relocation of R_TYPE going
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// from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
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// the branch target is a thumb instruction. TARGET is used for look
|
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// up ARM-specific linker settings.
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static Stub_type
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stub_type_for_reloc(unsigned int r_type, Arm_address branch_address,
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Arm_address branch_target, bool target_is_thumb);
|
||
|
||
// Reloc_stub key. A key is logically a triplet of a stub type, a symbol
|
||
// and an addend. Since we treat global and local symbol differently, we
|
||
// use a Symbol object for a global symbol and a object-index pair for
|
||
// a local symbol.
|
||
class Key
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||
{
|
||
public:
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||
// If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
|
||
// R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
|
||
// and R_SYM must not be invalid_index.
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||
Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj,
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unsigned int r_sym, int32_t addend)
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: stub_type_(stub_type), addend_(addend)
|
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{
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if (symbol != NULL)
|
||
{
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this->r_sym_ = Reloc_stub::invalid_index;
|
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this->u_.symbol = symbol;
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}
|
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else
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||
{
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gold_assert(relobj != NULL && r_sym != invalid_index);
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this->r_sym_ = r_sym;
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this->u_.relobj = relobj;
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}
|
||
}
|
||
|
||
~Key()
|
||
{ }
|
||
|
||
// Accessors: Keys are meant to be read-only object so no modifiers are
|
||
// provided.
|
||
|
||
// Return stub type.
|
||
Stub_type
|
||
stub_type() const
|
||
{ return this->stub_type_; }
|
||
|
||
// Return the local symbol index or invalid_index.
|
||
unsigned int
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||
r_sym() const
|
||
{ return this->r_sym_; }
|
||
|
||
// Return the symbol if there is one.
|
||
const Symbol*
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||
symbol() const
|
||
{ return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
|
||
|
||
// Return the relobj if there is one.
|
||
const Relobj*
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||
relobj() const
|
||
{ return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
|
||
|
||
// Whether this equals to another key k.
|
||
bool
|
||
eq(const Key& k) const
|
||
{
|
||
return ((this->stub_type_ == k.stub_type_)
|
||
&& (this->r_sym_ == k.r_sym_)
|
||
&& ((this->r_sym_ != Reloc_stub::invalid_index)
|
||
? (this->u_.relobj == k.u_.relobj)
|
||
: (this->u_.symbol == k.u_.symbol))
|
||
&& (this->addend_ == k.addend_));
|
||
}
|
||
|
||
// Return a hash value.
|
||
size_t
|
||
hash_value() const
|
||
{
|
||
return (this->stub_type_
|
||
^ this->r_sym_
|
||
^ gold::string_hash<char>(
|
||
(this->r_sym_ != Reloc_stub::invalid_index)
|
||
? this->u_.relobj->name().c_str()
|
||
: this->u_.symbol->name())
|
||
^ this->addend_);
|
||
}
|
||
|
||
// Functors for STL associative containers.
|
||
struct hash
|
||
{
|
||
size_t
|
||
operator()(const Key& k) const
|
||
{ return k.hash_value(); }
|
||
};
|
||
|
||
struct equal_to
|
||
{
|
||
bool
|
||
operator()(const Key& k1, const Key& k2) const
|
||
{ return k1.eq(k2); }
|
||
};
|
||
|
||
// Name of key. This is mainly for debugging.
|
||
std::string
|
||
name() const;
|
||
|
||
private:
|
||
// Stub type.
|
||
Stub_type stub_type_;
|
||
// If this is a local symbol, this is the index in the defining object.
|
||
// Otherwise, it is invalid_index for a global symbol.
|
||
unsigned int r_sym_;
|
||
// If r_sym_ is invalid index. This points to a global symbol.
|
||
// Otherwise, this points a relobj. We used the unsized and target
|
||
// independent Symbol and Relobj classes instead of Arm_symbol and
|
||
// Arm_relobj. This is done to avoid making the stub class a template
|
||
// as most of the stub machinery is endianity-neutral. However, it
|
||
// may require a bit of casting done by users of this class.
|
||
union
|
||
{
|
||
const Symbol* symbol;
|
||
const Relobj* relobj;
|
||
} u_;
|
||
// Addend associated with a reloc.
|
||
int32_t addend_;
|
||
};
|
||
|
||
protected:
|
||
// Reloc_stubs are created via a stub factory. So these are protected.
|
||
Reloc_stub(const Stub_template* stub_template)
|
||
: Stub(stub_template), destination_address_(invalid_address)
|
||
{ }
|
||
|
||
~Reloc_stub()
|
||
{ }
|
||
|
||
friend class Stub_factory;
|
||
|
||
private:
|
||
// Return the relocation target address of the i-th relocation in the
|
||
// stub.
|
||
Arm_address
|
||
do_reloc_target(size_t i)
|
||
{
|
||
// All reloc stub have only one relocation.
|
||
gold_assert(i == 0);
|
||
return this->destination_address_;
|
||
}
|
||
|
||
// A template to implement do_write below.
|
||
template<bool big_endian>
|
||
void inline
|
||
do_fixed_endian_write(unsigned char*, section_size_type);
|
||
|
||
// Write a stub.
|
||
void
|
||
do_write(unsigned char* view, section_size_type view_size, bool big_endian);
|
||
|
||
// Address of destination.
|
||
Arm_address destination_address_;
|
||
};
|
||
|
||
// Stub factory class.
|
||
|
||
class Stub_factory
|
||
{
|
||
public:
|
||
// Return the unique instance of this class.
|
||
static const Stub_factory&
|
||
get_instance()
|
||
{
|
||
static Stub_factory singleton;
|
||
return singleton;
|
||
}
|
||
|
||
// Make a relocation stub.
|
||
Reloc_stub*
|
||
make_reloc_stub(Stub_type stub_type) const
|
||
{
|
||
gold_assert(stub_type >= arm_stub_reloc_first
|
||
&& stub_type <= arm_stub_reloc_last);
|
||
return new Reloc_stub(this->stub_templates_[stub_type]);
|
||
}
|
||
|
||
private:
|
||
// Constructor and destructor are protected since we only return a single
|
||
// instance created in Stub_factory::get_instance().
|
||
|
||
Stub_factory();
|
||
|
||
// A Stub_factory may not be copied since it is a singleton.
|
||
Stub_factory(const Stub_factory&);
|
||
Stub_factory& operator=(Stub_factory&);
|
||
|
||
// Stub templates. These are initialized in the constructor.
|
||
const Stub_template* stub_templates_[arm_stub_type_last+1];
|
||
};
|
||
|
||
// A class to hold stubs for the ARM target.
|
||
|
||
template<bool big_endian>
|
||
class Stub_table : public Output_data
|
||
{
|
||
public:
|
||
Stub_table(Arm_input_section<big_endian>* owner)
|
||
: Output_data(), addralign_(1), owner_(owner), has_been_changed_(false),
|
||
reloc_stubs_()
|
||
{ }
|
||
|
||
~Stub_table()
|
||
{ }
|
||
|
||
// Owner of this stub table.
|
||
Arm_input_section<big_endian>*
|
||
owner() const
|
||
{ return this->owner_; }
|
||
|
||
// Whether this stub table is empty.
|
||
bool
|
||
empty() const
|
||
{ return this->reloc_stubs_.empty(); }
|
||
|
||
// Whether this has been changed.
|
||
bool
|
||
has_been_changed() const
|
||
{ return this->has_been_changed_; }
|
||
|
||
// Set the has-been-changed flag.
|
||
void
|
||
set_has_been_changed(bool value)
|
||
{ this->has_been_changed_ = value; }
|
||
|
||
// Return the current data size.
|
||
off_t
|
||
current_data_size() const
|
||
{ return this->current_data_size_for_child(); }
|
||
|
||
// Add a STUB with using KEY. Caller is reponsible for avoid adding
|
||
// if already a STUB with the same key has been added.
|
||
void
|
||
add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key);
|
||
|
||
// Look up a relocation stub using KEY. Return NULL if there is none.
|
||
Reloc_stub*
|
||
find_reloc_stub(const Reloc_stub::Key& key) const
|
||
{
|
||
typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key);
|
||
return (p != this->reloc_stubs_.end()) ? p->second : NULL;
|
||
}
|
||
|
||
// Relocate stubs in this stub table.
|
||
void
|
||
relocate_stubs(const Relocate_info<32, big_endian>*,
|
||
Target_arm<big_endian>*, Output_section*,
|
||
unsigned char*, Arm_address, section_size_type);
|
||
|
||
protected:
|
||
// Write out section contents.
|
||
void
|
||
do_write(Output_file*);
|
||
|
||
// Return the required alignment.
|
||
uint64_t
|
||
do_addralign() const
|
||
{ return this->addralign_; }
|
||
|
||
// Finalize data size.
|
||
void
|
||
set_final_data_size()
|
||
{ this->set_data_size(this->current_data_size_for_child()); }
|
||
|
||
// Reset address and file offset.
|
||
void
|
||
do_reset_address_and_file_offset();
|
||
|
||
private:
|
||
// Unordered map of stubs.
|
||
typedef
|
||
Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash,
|
||
Reloc_stub::Key::equal_to>
|
||
Reloc_stub_map;
|
||
|
||
// Address alignment
|
||
uint64_t addralign_;
|
||
// Owner of this stub table.
|
||
Arm_input_section<big_endian>* owner_;
|
||
// This is set to true during relaxiong if the size of the stub table
|
||
// has been changed.
|
||
bool has_been_changed_;
|
||
// The relocation stubs.
|
||
Reloc_stub_map reloc_stubs_;
|
||
};
|
||
|
||
// A class to wrap an ordinary input section containing executable code.
|
||
|
||
template<bool big_endian>
|
||
class Arm_input_section : public Output_relaxed_input_section
|
||
{
|
||
public:
|
||
Arm_input_section(Relobj* relobj, unsigned int shndx)
|
||
: Output_relaxed_input_section(relobj, shndx, 1),
|
||
original_addralign_(1), original_size_(0), stub_table_(NULL)
|
||
{ }
|
||
|
||
~Arm_input_section()
|
||
{ }
|
||
|
||
// Initialize.
|
||
void
|
||
init();
|
||
|
||
// Whether this is a stub table owner.
|
||
bool
|
||
is_stub_table_owner() const
|
||
{ return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
|
||
|
||
// Return the stub table.
|
||
Stub_table<big_endian>*
|
||
stub_table() const
|
||
{ return this->stub_table_; }
|
||
|
||
// Set the stub_table.
|
||
void
|
||
set_stub_table(Stub_table<big_endian>* stub_table)
|
||
{ this->stub_table_ = stub_table; }
|
||
|
||
// Downcast a base pointer to an Arm_input_section pointer. This is
|
||
// not type-safe but we only use Arm_input_section not the base class.
|
||
static Arm_input_section<big_endian>*
|
||
as_arm_input_section(Output_relaxed_input_section* poris)
|
||
{ return static_cast<Arm_input_section<big_endian>*>(poris); }
|
||
|
||
protected:
|
||
// Write data to output file.
|
||
void
|
||
do_write(Output_file*);
|
||
|
||
// Return required alignment of this.
|
||
uint64_t
|
||
do_addralign() const
|
||
{
|
||
if (this->is_stub_table_owner())
|
||
return std::max(this->stub_table_->addralign(),
|
||
this->original_addralign_);
|
||
else
|
||
return this->original_addralign_;
|
||
}
|
||
|
||
// Finalize data size.
|
||
void
|
||
set_final_data_size();
|
||
|
||
// Reset address and file offset.
|
||
void
|
||
do_reset_address_and_file_offset();
|
||
|
||
// Output offset.
|
||
bool
|
||
do_output_offset(const Relobj* object, unsigned int shndx,
|
||
section_offset_type offset,
|
||
section_offset_type* poutput) const
|
||
{
|
||
if ((object == this->relobj())
|
||
&& (shndx == this->shndx())
|
||
&& (offset >= 0)
|
||
&& (convert_types<uint64_t, section_offset_type>(offset)
|
||
<= this->original_size_))
|
||
{
|
||
*poutput = offset;
|
||
return true;
|
||
}
|
||
else
|
||
return false;
|
||
}
|
||
|
||
private:
|
||
// Copying is not allowed.
|
||
Arm_input_section(const Arm_input_section&);
|
||
Arm_input_section& operator=(const Arm_input_section&);
|
||
|
||
// Address alignment of the original input section.
|
||
uint64_t original_addralign_;
|
||
// Section size of the original input section.
|
||
uint64_t original_size_;
|
||
// Stub table.
|
||
Stub_table<big_endian>* stub_table_;
|
||
};
|
||
|
||
// Arm output section class. This is defined mainly to add a number of
|
||
// stub generation methods.
|
||
|
||
template<bool big_endian>
|
||
class Arm_output_section : public Output_section
|
||
{
|
||
public:
|
||
Arm_output_section(const char* name, elfcpp::Elf_Word type,
|
||
elfcpp::Elf_Xword flags)
|
||
: Output_section(name, type, flags)
|
||
{ }
|
||
|
||
~Arm_output_section()
|
||
{ }
|
||
|
||
// Group input sections for stub generation.
|
||
void
|
||
group_sections(section_size_type, bool, Target_arm<big_endian>*);
|
||
|
||
// Downcast a base pointer to an Arm_output_section pointer. This is
|
||
// not type-safe but we only use Arm_output_section not the base class.
|
||
static Arm_output_section<big_endian>*
|
||
as_arm_output_section(Output_section* os)
|
||
{ return static_cast<Arm_output_section<big_endian>*>(os); }
|
||
|
||
private:
|
||
// For convenience.
|
||
typedef Output_section::Input_section Input_section;
|
||
typedef Output_section::Input_section_list Input_section_list;
|
||
|
||
// Create a stub group.
|
||
void create_stub_group(Input_section_list::const_iterator,
|
||
Input_section_list::const_iterator,
|
||
Input_section_list::const_iterator,
|
||
Target_arm<big_endian>*,
|
||
std::vector<Output_relaxed_input_section*>*);
|
||
};
|
||
|
||
// Utilities for manipulating integers of up to 32-bits
|
||
|
||
namespace utils
|
||
{
|
||
// Sign extend an n-bit unsigned integer stored in an uint32_t into
|
||
// an int32_t. NO_BITS must be between 1 to 32.
|
||
template<int no_bits>
|
||
static inline int32_t
|
||
sign_extend(uint32_t bits)
|
||
{
|
||
gold_assert(no_bits >= 0 && no_bits <= 32);
|
||
if (no_bits == 32)
|
||
return static_cast<int32_t>(bits);
|
||
uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
|
||
bits &= mask;
|
||
uint32_t top_bit = 1U << (no_bits - 1);
|
||
int32_t as_signed = static_cast<int32_t>(bits);
|
||
return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
|
||
}
|
||
|
||
// Detects overflow of an NO_BITS integer stored in a uint32_t.
|
||
template<int no_bits>
|
||
static inline bool
|
||
has_overflow(uint32_t bits)
|
||
{
|
||
gold_assert(no_bits >= 0 && no_bits <= 32);
|
||
if (no_bits == 32)
|
||
return false;
|
||
int32_t max = (1 << (no_bits - 1)) - 1;
|
||
int32_t min = -(1 << (no_bits - 1));
|
||
int32_t as_signed = static_cast<int32_t>(bits);
|
||
return as_signed > max || as_signed < min;
|
||
}
|
||
|
||
// Detects overflow of an NO_BITS integer stored in a uint32_t when it
|
||
// fits in the given number of bits as either a signed or unsigned value.
|
||
// For example, has_signed_unsigned_overflow<8> would check
|
||
// -128 <= bits <= 255
|
||
template<int no_bits>
|
||
static inline bool
|
||
has_signed_unsigned_overflow(uint32_t bits)
|
||
{
|
||
gold_assert(no_bits >= 2 && no_bits <= 32);
|
||
if (no_bits == 32)
|
||
return false;
|
||
int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
|
||
int32_t min = -(1 << (no_bits - 1));
|
||
int32_t as_signed = static_cast<int32_t>(bits);
|
||
return as_signed > max || as_signed < min;
|
||
}
|
||
|
||
// Select bits from A and B using bits in MASK. For each n in [0..31],
|
||
// the n-th bit in the result is chosen from the n-th bits of A and B.
|
||
// A zero selects A and a one selects B.
|
||
static inline uint32_t
|
||
bit_select(uint32_t a, uint32_t b, uint32_t mask)
|
||
{ return (a & ~mask) | (b & mask); }
|
||
};
|
||
|
||
template<bool big_endian>
|
||
class Target_arm : public Sized_target<32, big_endian>
|
||
{
|
||
public:
|
||
typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
|
||
Reloc_section;
|
||
|
||
Target_arm()
|
||
: Sized_target<32, big_endian>(&arm_info),
|
||
got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
|
||
copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
|
||
may_use_blx_(true), should_force_pic_veneer_(false)
|
||
{ }
|
||
|
||
// Whether we can use BLX.
|
||
bool
|
||
may_use_blx() const
|
||
{ return this->may_use_blx_; }
|
||
|
||
// Set use-BLX flag.
|
||
void
|
||
set_may_use_blx(bool value)
|
||
{ this->may_use_blx_ = value; }
|
||
|
||
// Whether we force PCI branch veneers.
|
||
bool
|
||
should_force_pic_veneer() const
|
||
{ return this->should_force_pic_veneer_; }
|
||
|
||
// Set PIC veneer flag.
|
||
void
|
||
set_should_force_pic_veneer(bool value)
|
||
{ this->should_force_pic_veneer_ = value; }
|
||
|
||
// Whether we use THUMB-2 instructions.
|
||
bool
|
||
using_thumb2() const
|
||
{
|
||
// FIXME: This should not hard-coded.
|
||
return false;
|
||
}
|
||
|
||
// Whether we use THUMB/THUMB-2 instructions only.
|
||
bool
|
||
using_thumb_only() const
|
||
{
|
||
// FIXME: This should not hard-coded.
|
||
return false;
|
||
}
|
||
|
||
// Process the relocations to determine unreferenced sections for
|
||
// garbage collection.
|
||
void
|
||
gc_process_relocs(const General_options& options,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
size_t local_symbol_count,
|
||
const unsigned char* plocal_symbols);
|
||
|
||
// Scan the relocations to look for symbol adjustments.
|
||
void
|
||
scan_relocs(const General_options& options,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
size_t local_symbol_count,
|
||
const unsigned char* plocal_symbols);
|
||
|
||
// Finalize the sections.
|
||
void
|
||
do_finalize_sections(Layout*);
|
||
|
||
// Return the value to use for a dynamic symbol which requires special
|
||
// treatment.
|
||
uint64_t
|
||
do_dynsym_value(const Symbol*) const;
|
||
|
||
// Relocate a section.
|
||
void
|
||
relocate_section(const Relocate_info<32, big_endian>*,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr view_address,
|
||
section_size_type view_size,
|
||
const Reloc_symbol_changes*);
|
||
|
||
// Scan the relocs during a relocatable link.
|
||
void
|
||
scan_relocatable_relocs(const General_options& options,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
size_t local_symbol_count,
|
||
const unsigned char* plocal_symbols,
|
||
Relocatable_relocs*);
|
||
|
||
// Relocate a section during a relocatable link.
|
||
void
|
||
relocate_for_relocatable(const Relocate_info<32, big_endian>*,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
off_t offset_in_output_section,
|
||
const Relocatable_relocs*,
|
||
unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr view_address,
|
||
section_size_type view_size,
|
||
unsigned char* reloc_view,
|
||
section_size_type reloc_view_size);
|
||
|
||
// Return whether SYM is defined by the ABI.
|
||
bool
|
||
do_is_defined_by_abi(Symbol* sym) const
|
||
{ return strcmp(sym->name(), "__tls_get_addr") == 0; }
|
||
|
||
// Return the size of the GOT section.
|
||
section_size_type
|
||
got_size()
|
||
{
|
||
gold_assert(this->got_ != NULL);
|
||
return this->got_->data_size();
|
||
}
|
||
|
||
// Map platform-specific reloc types
|
||
static unsigned int
|
||
get_real_reloc_type (unsigned int r_type);
|
||
|
||
// Get the default ARM target.
|
||
static const Target_arm<big_endian>&
|
||
default_target()
|
||
{
|
||
gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
|
||
&& parameters->target().is_big_endian() == big_endian);
|
||
return static_cast<const Target_arm<big_endian>&>(parameters->target());
|
||
}
|
||
|
||
private:
|
||
// The class which scans relocations.
|
||
class Scan
|
||
{
|
||
public:
|
||
Scan()
|
||
: issued_non_pic_error_(false)
|
||
{ }
|
||
|
||
inline void
|
||
local(const General_options& options, Symbol_table* symtab,
|
||
Layout* layout, Target_arm* target,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
Output_section* output_section,
|
||
const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
|
||
const elfcpp::Sym<32, big_endian>& lsym);
|
||
|
||
inline void
|
||
global(const General_options& options, Symbol_table* symtab,
|
||
Layout* layout, Target_arm* target,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
Output_section* output_section,
|
||
const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
|
||
Symbol* gsym);
|
||
|
||
private:
|
||
static void
|
||
unsupported_reloc_local(Sized_relobj<32, big_endian>*,
|
||
unsigned int r_type);
|
||
|
||
static void
|
||
unsupported_reloc_global(Sized_relobj<32, big_endian>*,
|
||
unsigned int r_type, Symbol*);
|
||
|
||
void
|
||
check_non_pic(Relobj*, unsigned int r_type);
|
||
|
||
// Almost identical to Symbol::needs_plt_entry except that it also
|
||
// handles STT_ARM_TFUNC.
|
||
static bool
|
||
symbol_needs_plt_entry(const Symbol* sym)
|
||
{
|
||
// An undefined symbol from an executable does not need a PLT entry.
|
||
if (sym->is_undefined() && !parameters->options().shared())
|
||
return false;
|
||
|
||
return (!parameters->doing_static_link()
|
||
&& (sym->type() == elfcpp::STT_FUNC
|
||
|| sym->type() == elfcpp::STT_ARM_TFUNC)
|
||
&& (sym->is_from_dynobj()
|
||
|| sym->is_undefined()
|
||
|| sym->is_preemptible()));
|
||
}
|
||
|
||
// Whether we have issued an error about a non-PIC compilation.
|
||
bool issued_non_pic_error_;
|
||
};
|
||
|
||
// The class which implements relocation.
|
||
class Relocate
|
||
{
|
||
public:
|
||
Relocate()
|
||
{ }
|
||
|
||
~Relocate()
|
||
{ }
|
||
|
||
// Return whether the static relocation needs to be applied.
|
||
inline bool
|
||
should_apply_static_reloc(const Sized_symbol<32>* gsym,
|
||
int ref_flags,
|
||
bool is_32bit,
|
||
Output_section* output_section);
|
||
|
||
// Do a relocation. Return false if the caller should not issue
|
||
// any warnings about this relocation.
|
||
inline bool
|
||
relocate(const Relocate_info<32, big_endian>*, Target_arm*,
|
||
Output_section*, size_t relnum,
|
||
const elfcpp::Rel<32, big_endian>&,
|
||
unsigned int r_type, const Sized_symbol<32>*,
|
||
const Symbol_value<32>*,
|
||
unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
|
||
section_size_type);
|
||
|
||
// Return whether we want to pass flag NON_PIC_REF for this
|
||
// reloc.
|
||
static inline bool
|
||
reloc_is_non_pic (unsigned int r_type)
|
||
{
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_REL32:
|
||
case elfcpp::R_ARM_THM_CALL:
|
||
case elfcpp::R_ARM_CALL:
|
||
case elfcpp::R_ARM_JUMP24:
|
||
case elfcpp::R_ARM_PREL31:
|
||
case elfcpp::R_ARM_THM_ABS5:
|
||
case elfcpp::R_ARM_ABS8:
|
||
case elfcpp::R_ARM_ABS12:
|
||
case elfcpp::R_ARM_ABS16:
|
||
case elfcpp::R_ARM_BASE_ABS:
|
||
return true;
|
||
default:
|
||
return false;
|
||
}
|
||
}
|
||
};
|
||
|
||
// A class which returns the size required for a relocation type,
|
||
// used while scanning relocs during a relocatable link.
|
||
class Relocatable_size_for_reloc
|
||
{
|
||
public:
|
||
unsigned int
|
||
get_size_for_reloc(unsigned int, Relobj*);
|
||
};
|
||
|
||
// Get the GOT section, creating it if necessary.
|
||
Output_data_got<32, big_endian>*
|
||
got_section(Symbol_table*, Layout*);
|
||
|
||
// Get the GOT PLT section.
|
||
Output_data_space*
|
||
got_plt_section() const
|
||
{
|
||
gold_assert(this->got_plt_ != NULL);
|
||
return this->got_plt_;
|
||
}
|
||
|
||
// Create a PLT entry for a global symbol.
|
||
void
|
||
make_plt_entry(Symbol_table*, Layout*, Symbol*);
|
||
|
||
// Get the PLT section.
|
||
const Output_data_plt_arm<big_endian>*
|
||
plt_section() const
|
||
{
|
||
gold_assert(this->plt_ != NULL);
|
||
return this->plt_;
|
||
}
|
||
|
||
// Get the dynamic reloc section, creating it if necessary.
|
||
Reloc_section*
|
||
rel_dyn_section(Layout*);
|
||
|
||
// Return true if the symbol may need a COPY relocation.
|
||
// References from an executable object to non-function symbols
|
||
// defined in a dynamic object may need a COPY relocation.
|
||
bool
|
||
may_need_copy_reloc(Symbol* gsym)
|
||
{
|
||
return (gsym->type() != elfcpp::STT_ARM_TFUNC
|
||
&& gsym->may_need_copy_reloc());
|
||
}
|
||
|
||
// Add a potential copy relocation.
|
||
void
|
||
copy_reloc(Symbol_table* symtab, Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int shndx, Output_section* output_section,
|
||
Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
|
||
{
|
||
this->copy_relocs_.copy_reloc(symtab, layout,
|
||
symtab->get_sized_symbol<32>(sym),
|
||
object, shndx, output_section, reloc,
|
||
this->rel_dyn_section(layout));
|
||
}
|
||
|
||
// Information about this specific target which we pass to the
|
||
// general Target structure.
|
||
static const Target::Target_info arm_info;
|
||
|
||
// The types of GOT entries needed for this platform.
|
||
enum Got_type
|
||
{
|
||
GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol
|
||
};
|
||
|
||
// The GOT section.
|
||
Output_data_got<32, big_endian>* got_;
|
||
// The PLT section.
|
||
Output_data_plt_arm<big_endian>* plt_;
|
||
// The GOT PLT section.
|
||
Output_data_space* got_plt_;
|
||
// The dynamic reloc section.
|
||
Reloc_section* rel_dyn_;
|
||
// Relocs saved to avoid a COPY reloc.
|
||
Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
|
||
// Space for variables copied with a COPY reloc.
|
||
Output_data_space* dynbss_;
|
||
// Whether we can use BLX.
|
||
bool may_use_blx_;
|
||
// Whether we force PIC branch veneers.
|
||
bool should_force_pic_veneer_;
|
||
};
|
||
|
||
template<bool big_endian>
|
||
const Target::Target_info Target_arm<big_endian>::arm_info =
|
||
{
|
||
32, // size
|
||
big_endian, // is_big_endian
|
||
elfcpp::EM_ARM, // machine_code
|
||
false, // has_make_symbol
|
||
false, // has_resolve
|
||
false, // has_code_fill
|
||
true, // is_default_stack_executable
|
||
'\0', // wrap_char
|
||
"/usr/lib/libc.so.1", // dynamic_linker
|
||
0x8000, // default_text_segment_address
|
||
0x1000, // abi_pagesize (overridable by -z max-page-size)
|
||
0x1000, // common_pagesize (overridable by -z common-page-size)
|
||
elfcpp::SHN_UNDEF, // small_common_shndx
|
||
elfcpp::SHN_UNDEF, // large_common_shndx
|
||
0, // small_common_section_flags
|
||
0 // large_common_section_flags
|
||
};
|
||
|
||
// Arm relocate functions class
|
||
//
|
||
|
||
template<bool big_endian>
|
||
class Arm_relocate_functions : public Relocate_functions<32, big_endian>
|
||
{
|
||
public:
|
||
typedef enum
|
||
{
|
||
STATUS_OKAY, // No error during relocation.
|
||
STATUS_OVERFLOW, // Relocation oveflow.
|
||
STATUS_BAD_RELOC // Relocation cannot be applied.
|
||
} Status;
|
||
|
||
private:
|
||
typedef Relocate_functions<32, big_endian> Base;
|
||
typedef Arm_relocate_functions<big_endian> This;
|
||
|
||
// Get an symbol value of *PSYMVAL with an ADDEND. This is a wrapper
|
||
// to Symbol_value::value(). If HAS_THUMB_BIT is true, that LSB is used
|
||
// to distinguish ARM and THUMB functions and it is treated specially.
|
||
static inline Symbol_value<32>::Value
|
||
arm_symbol_value (const Sized_relobj<32, big_endian> *object,
|
||
const Symbol_value<32>* psymval,
|
||
Symbol_value<32>::Value addend,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef Symbol_value<32>::Value Valtype;
|
||
|
||
if (has_thumb_bit)
|
||
{
|
||
Valtype raw = psymval->value(object, 0);
|
||
Valtype thumb_bit = raw & 1;
|
||
return ((raw & ~((Valtype) 1)) + addend) | thumb_bit;
|
||
}
|
||
else
|
||
return psymval->value(object, addend);
|
||
}
|
||
|
||
// Encoding of imm16 argument for movt and movw ARM instructions
|
||
// from ARM ARM:
|
||
//
|
||
// imm16 := imm4 | imm12
|
||
//
|
||
// f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
|
||
// +-------+---------------+-------+-------+-----------------------+
|
||
// | | |imm4 | |imm12 |
|
||
// +-------+---------------+-------+-------+-----------------------+
|
||
|
||
// Extract the relocation addend from VAL based on the ARM
|
||
// instruction encoding described above.
|
||
static inline typename elfcpp::Swap<32, big_endian>::Valtype
|
||
extract_arm_movw_movt_addend(
|
||
typename elfcpp::Swap<32, big_endian>::Valtype val)
|
||
{
|
||
// According to the Elf ABI for ARM Architecture the immediate
|
||
// field is sign-extended to form the addend.
|
||
return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
|
||
}
|
||
|
||
// Insert X into VAL based on the ARM instruction encoding described
|
||
// above.
|
||
static inline typename elfcpp::Swap<32, big_endian>::Valtype
|
||
insert_val_arm_movw_movt(
|
||
typename elfcpp::Swap<32, big_endian>::Valtype val,
|
||
typename elfcpp::Swap<32, big_endian>::Valtype x)
|
||
{
|
||
val &= 0xfff0f000;
|
||
val |= x & 0x0fff;
|
||
val |= (x & 0xf000) << 4;
|
||
return val;
|
||
}
|
||
|
||
// Encoding of imm16 argument for movt and movw Thumb2 instructions
|
||
// from ARM ARM:
|
||
//
|
||
// imm16 := imm4 | i | imm3 | imm8
|
||
//
|
||
// f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
|
||
// +---------+-+-----------+-------++-+-----+-------+---------------+
|
||
// | |i| |imm4 || |imm3 | |imm8 |
|
||
// +---------+-+-----------+-------++-+-----+-------+---------------+
|
||
|
||
// Extract the relocation addend from VAL based on the Thumb2
|
||
// instruction encoding described above.
|
||
static inline typename elfcpp::Swap<32, big_endian>::Valtype
|
||
extract_thumb_movw_movt_addend(
|
||
typename elfcpp::Swap<32, big_endian>::Valtype val)
|
||
{
|
||
// According to the Elf ABI for ARM Architecture the immediate
|
||
// field is sign-extended to form the addend.
|
||
return utils::sign_extend<16>(((val >> 4) & 0xf000)
|
||
| ((val >> 15) & 0x0800)
|
||
| ((val >> 4) & 0x0700)
|
||
| (val & 0x00ff));
|
||
}
|
||
|
||
// Insert X into VAL based on the Thumb2 instruction encoding
|
||
// described above.
|
||
static inline typename elfcpp::Swap<32, big_endian>::Valtype
|
||
insert_val_thumb_movw_movt(
|
||
typename elfcpp::Swap<32, big_endian>::Valtype val,
|
||
typename elfcpp::Swap<32, big_endian>::Valtype x)
|
||
{
|
||
val &= 0xfbf08f00;
|
||
val |= (x & 0xf000) << 4;
|
||
val |= (x & 0x0800) << 15;
|
||
val |= (x & 0x0700) << 4;
|
||
val |= (x & 0x00ff);
|
||
return val;
|
||
}
|
||
|
||
// FIXME: This probably only works for Android on ARM v5te. We should
|
||
// following GNU ld for the general case.
|
||
template<unsigned r_type>
|
||
static inline typename This::Status
|
||
arm_branch_common(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
|
||
bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
|
||
&& ((val & 0x0f000000UL) == 0x0a000000UL);
|
||
bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
|
||
bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
|
||
&& ((val & 0x0f000000UL) == 0x0b000000UL);
|
||
bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
|
||
bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
|
||
|
||
if (r_type == elfcpp::R_ARM_CALL)
|
||
{
|
||
if (!insn_is_uncond_bl && !insn_is_blx)
|
||
return This::STATUS_BAD_RELOC;
|
||
}
|
||
else if (r_type == elfcpp::R_ARM_JUMP24)
|
||
{
|
||
if (!insn_is_b && !insn_is_cond_bl)
|
||
return This::STATUS_BAD_RELOC;
|
||
}
|
||
else if (r_type == elfcpp::R_ARM_PLT32)
|
||
{
|
||
if (!insn_is_any_branch)
|
||
return This::STATUS_BAD_RELOC;
|
||
}
|
||
else
|
||
gold_unreachable();
|
||
|
||
Valtype addend = utils::sign_extend<26>(val << 2);
|
||
Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
|
||
- address);
|
||
|
||
// If target has thumb bit set, we need to either turn the BL
|
||
// into a BLX (for ARMv5 or above) or generate a stub.
|
||
if (x & 1)
|
||
{
|
||
// Turn BL to BLX.
|
||
if (insn_is_uncond_bl)
|
||
val = (val & 0xffffff) | 0xfa000000 | ((x & 2) << 23);
|
||
else
|
||
return This::STATUS_BAD_RELOC;
|
||
}
|
||
else
|
||
gold_assert(!insn_is_blx);
|
||
|
||
val = utils::bit_select(val, (x >> 2), 0xffffffUL);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return (utils::has_overflow<26>(x)
|
||
? This::STATUS_OVERFLOW : This::STATUS_OKAY);
|
||
}
|
||
|
||
public:
|
||
|
||
// R_ARM_ABS8: S + A
|
||
static inline typename This::Status
|
||
abs8(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval)
|
||
{
|
||
typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
|
||
Reltype addend = utils::sign_extend<8>(val);
|
||
Reltype x = This::arm_symbol_value(object, psymval, addend, false);
|
||
val = utils::bit_select(val, x, 0xffU);
|
||
elfcpp::Swap<8, big_endian>::writeval(wv, val);
|
||
return (utils::has_signed_unsigned_overflow<8>(x)
|
||
? This::STATUS_OVERFLOW
|
||
: This::STATUS_OKAY);
|
||
}
|
||
|
||
// R_ARM_THM_ABS5: S + A
|
||
static inline typename This::Status
|
||
thm_abs5(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval)
|
||
{
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
|
||
Reltype addend = (val & 0x7e0U) >> 6;
|
||
Reltype x = This::arm_symbol_value(object, psymval, addend, false);
|
||
val = utils::bit_select(val, x << 6, 0x7e0U);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, val);
|
||
return (utils::has_overflow<5>(x)
|
||
? This::STATUS_OVERFLOW
|
||
: This::STATUS_OKAY);
|
||
}
|
||
|
||
// R_ARM_ABS12: S + A
|
||
static inline typename This::Status
|
||
abs12(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Reltype addend = val & 0x0fffU;
|
||
Reltype x = This::arm_symbol_value(object, psymval, addend, false);
|
||
val = utils::bit_select(val, x, 0x0fffU);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return (utils::has_overflow<12>(x)
|
||
? This::STATUS_OVERFLOW
|
||
: This::STATUS_OKAY);
|
||
}
|
||
|
||
// R_ARM_ABS16: S + A
|
||
static inline typename This::Status
|
||
abs16(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval)
|
||
{
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
|
||
Reltype addend = utils::sign_extend<16>(val);
|
||
Reltype x = This::arm_symbol_value(object, psymval, addend, false);
|
||
val = utils::bit_select(val, x, 0xffffU);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, val);
|
||
return (utils::has_signed_unsigned_overflow<16>(x)
|
||
? This::STATUS_OVERFLOW
|
||
: This::STATUS_OKAY);
|
||
}
|
||
|
||
// R_ARM_ABS32: (S + A) | T
|
||
static inline typename This::Status
|
||
abs32(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, x);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_REL32: (S + A) | T - P
|
||
static inline typename This::Status
|
||
rel32(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
|
||
- address);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, x);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_THM_CALL: (S + A) | T - P
|
||
static inline typename This::Status
|
||
thm_call(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
// A thumb call consists of two instructions.
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype hi = elfcpp::Swap<16, big_endian>::readval(wv);
|
||
Valtype lo = elfcpp::Swap<16, big_endian>::readval(wv + 1);
|
||
// Must be a BL instruction. lo == 11111xxxxxxxxxxx.
|
||
gold_assert((lo & 0xf800) == 0xf800);
|
||
Reltype addend = utils::sign_extend<23>(((hi & 0x7ff) << 12)
|
||
| ((lo & 0x7ff) << 1));
|
||
Reltype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
|
||
- address);
|
||
|
||
// If target has no thumb bit set, we need to either turn the BL
|
||
// into a BLX (for ARMv5 or above) or generate a stub.
|
||
if ((x & 1) == 0)
|
||
{
|
||
// This only works for ARMv5 and above with interworking enabled.
|
||
lo &= 0xefff;
|
||
}
|
||
hi = utils::bit_select(hi, (x >> 12), 0x7ffU);
|
||
lo = utils::bit_select(lo, (x >> 1), 0x7ffU);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, hi);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv + 1, lo);
|
||
return (utils::has_overflow<23>(x)
|
||
? This::STATUS_OVERFLOW
|
||
: This::STATUS_OKAY);
|
||
}
|
||
|
||
// R_ARM_BASE_PREL: B(S) + A - P
|
||
static inline typename This::Status
|
||
base_prel(unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr origin,
|
||
elfcpp::Elf_types<32>::Elf_Addr address)
|
||
{
|
||
Base::rel32(view, origin - address);
|
||
return STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_BASE_ABS: B(S) + A
|
||
static inline typename This::Status
|
||
base_abs(unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr origin)
|
||
{
|
||
Base::rel32(view, origin);
|
||
return STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
|
||
static inline typename This::Status
|
||
got_brel(unsigned char* view,
|
||
typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
|
||
{
|
||
Base::rel32(view, got_offset);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_GOT_PREL: GOT(S) + A – P
|
||
static inline typename This::Status
|
||
got_prel(unsigned char* view,
|
||
typename elfcpp::Swap<32, big_endian>::Valtype got_offset,
|
||
elfcpp::Elf_types<32>::Elf_Addr address)
|
||
{
|
||
Base::rel32(view, got_offset - address);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_PLT32: (S + A) | T - P
|
||
static inline typename This::Status
|
||
plt32(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
return arm_branch_common<elfcpp::R_ARM_PLT32>(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
}
|
||
|
||
// R_ARM_CALL: (S + A) | T - P
|
||
static inline typename This::Status
|
||
call(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
return arm_branch_common<elfcpp::R_ARM_CALL>(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
}
|
||
|
||
// R_ARM_JUMP24: (S + A) | T - P
|
||
static inline typename This::Status
|
||
jump24(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
return arm_branch_common<elfcpp::R_ARM_JUMP24>(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
}
|
||
|
||
// R_ARM_PREL: (S + A) | T - P
|
||
static inline typename This::Status
|
||
prel31(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype addend = utils::sign_extend<31>(val);
|
||
Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
|
||
- address);
|
||
val = utils::bit_select(val, x, 0x7fffffffU);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return (utils::has_overflow<31>(x) ?
|
||
This::STATUS_OVERFLOW : This::STATUS_OKAY);
|
||
}
|
||
|
||
// R_ARM_MOVW_ABS_NC: (S + A) | T
|
||
static inline typename This::Status
|
||
movw_abs_nc(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype addend = This::extract_arm_movw_movt_addend(val);
|
||
Valtype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit);
|
||
val = This::insert_val_arm_movw_movt(val, x);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_MOVT_ABS: S + A
|
||
static inline typename This::Status
|
||
movt_abs(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype addend = This::extract_arm_movw_movt_addend(val);
|
||
Valtype x = This::arm_symbol_value(object, psymval, addend, 0) >> 16;
|
||
val = This::insert_val_arm_movw_movt(val, x);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_THM_MOVW_ABS_NC: S + A | T
|
||
static inline typename This::Status
|
||
thm_movw_abs_nc(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16)
|
||
| elfcpp::Swap<16, big_endian>::readval(wv + 1));
|
||
Reltype addend = extract_thumb_movw_movt_addend(val);
|
||
Reltype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit);
|
||
val = This::insert_val_thumb_movw_movt(val, x);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_THM_MOVT_ABS: S + A
|
||
static inline typename This::Status
|
||
thm_movt_abs(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval)
|
||
{
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16)
|
||
| elfcpp::Swap<16, big_endian>::readval(wv + 1));
|
||
Reltype addend = This::extract_thumb_movw_movt_addend(val);
|
||
Reltype x = This::arm_symbol_value(object, psymval, addend, 0) >> 16;
|
||
val = This::insert_val_thumb_movw_movt(val, x);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_MOVW_PREL_NC: (S + A) | T - P
|
||
static inline typename This::Status
|
||
movw_prel_nc(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype addend = This::extract_arm_movw_movt_addend(val);
|
||
Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
|
||
- address);
|
||
val = This::insert_val_arm_movw_movt(val, x);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_MOVT_PREL: S + A - P
|
||
static inline typename This::Status
|
||
movt_prel(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address)
|
||
{
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
|
||
Valtype addend = This::extract_arm_movw_movt_addend(val);
|
||
Valtype x = (This::arm_symbol_value(object, psymval, addend, 0)
|
||
- address) >> 16;
|
||
val = This::insert_val_arm_movw_movt(val, x);
|
||
elfcpp::Swap<32, big_endian>::writeval(wv, val);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
|
||
static inline typename This::Status
|
||
thm_movw_prel_nc(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
bool has_thumb_bit)
|
||
{
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
|
||
| elfcpp::Swap<16, big_endian>::readval(wv + 1);
|
||
Reltype addend = This::extract_thumb_movw_movt_addend(val);
|
||
Reltype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
|
||
- address);
|
||
val = This::insert_val_thumb_movw_movt(val, x);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
|
||
// R_ARM_THM_MOVT_PREL: S + A - P
|
||
static inline typename This::Status
|
||
thm_movt_prel(unsigned char *view,
|
||
const Sized_relobj<32, big_endian>* object,
|
||
const Symbol_value<32>* psymval,
|
||
elfcpp::Elf_types<32>::Elf_Addr address)
|
||
{
|
||
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
|
||
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
|
||
Valtype* wv = reinterpret_cast<Valtype*>(view);
|
||
Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
|
||
| elfcpp::Swap<16, big_endian>::readval(wv + 1);
|
||
Reltype addend = This::extract_thumb_movw_movt_addend(val);
|
||
Reltype x = (This::arm_symbol_value(object, psymval, addend, 0)
|
||
- address) >> 16;
|
||
val = This::insert_val_thumb_movw_movt(val, x);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
|
||
elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
|
||
return This::STATUS_OKAY;
|
||
}
|
||
};
|
||
|
||
// Get the GOT section, creating it if necessary.
|
||
|
||
template<bool big_endian>
|
||
Output_data_got<32, big_endian>*
|
||
Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
|
||
{
|
||
if (this->got_ == NULL)
|
||
{
|
||
gold_assert(symtab != NULL && layout != NULL);
|
||
|
||
this->got_ = new Output_data_got<32, big_endian>();
|
||
|
||
Output_section* os;
|
||
os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
|
||
(elfcpp::SHF_ALLOC
|
||
| elfcpp::SHF_WRITE),
|
||
this->got_);
|
||
os->set_is_relro();
|
||
|
||
// The old GNU linker creates a .got.plt section. We just
|
||
// create another set of data in the .got section. Note that we
|
||
// always create a PLT if we create a GOT, although the PLT
|
||
// might be empty.
|
||
this->got_plt_ = new Output_data_space(4, "** GOT PLT");
|
||
os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
|
||
(elfcpp::SHF_ALLOC
|
||
| elfcpp::SHF_WRITE),
|
||
this->got_plt_);
|
||
os->set_is_relro();
|
||
|
||
// The first three entries are reserved.
|
||
this->got_plt_->set_current_data_size(3 * 4);
|
||
|
||
// Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
|
||
symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
|
||
this->got_plt_,
|
||
0, 0, elfcpp::STT_OBJECT,
|
||
elfcpp::STB_LOCAL,
|
||
elfcpp::STV_HIDDEN, 0,
|
||
false, false);
|
||
}
|
||
return this->got_;
|
||
}
|
||
|
||
// Get the dynamic reloc section, creating it if necessary.
|
||
|
||
template<bool big_endian>
|
||
typename Target_arm<big_endian>::Reloc_section*
|
||
Target_arm<big_endian>::rel_dyn_section(Layout* layout)
|
||
{
|
||
if (this->rel_dyn_ == NULL)
|
||
{
|
||
gold_assert(layout != NULL);
|
||
this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
|
||
layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
|
||
elfcpp::SHF_ALLOC, this->rel_dyn_);
|
||
}
|
||
return this->rel_dyn_;
|
||
}
|
||
|
||
// Insn_template methods.
|
||
|
||
// Return byte size of an instruction template.
|
||
|
||
size_t
|
||
Insn_template::size() const
|
||
{
|
||
switch (this->type())
|
||
{
|
||
case THUMB16_TYPE:
|
||
return 2;
|
||
case ARM_TYPE:
|
||
case THUMB32_TYPE:
|
||
case DATA_TYPE:
|
||
return 4;
|
||
default:
|
||
gold_unreachable();
|
||
}
|
||
}
|
||
|
||
// Return alignment of an instruction template.
|
||
|
||
unsigned
|
||
Insn_template::alignment() const
|
||
{
|
||
switch (this->type())
|
||
{
|
||
case THUMB16_TYPE:
|
||
case THUMB32_TYPE:
|
||
return 2;
|
||
case ARM_TYPE:
|
||
case DATA_TYPE:
|
||
return 4;
|
||
default:
|
||
gold_unreachable();
|
||
}
|
||
}
|
||
|
||
// Stub_template methods.
|
||
|
||
Stub_template::Stub_template(
|
||
Stub_type type, const Insn_template* insns,
|
||
size_t insn_count)
|
||
: type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
|
||
entry_in_thumb_mode_(false), relocs_()
|
||
{
|
||
off_t offset = 0;
|
||
|
||
// Compute byte size and alignment of stub template.
|
||
for (size_t i = 0; i < insn_count; i++)
|
||
{
|
||
unsigned insn_alignment = insns[i].alignment();
|
||
size_t insn_size = insns[i].size();
|
||
gold_assert((offset & (insn_alignment - 1)) == 0);
|
||
this->alignment_ = std::max(this->alignment_, insn_alignment);
|
||
switch (insns[i].type())
|
||
{
|
||
case Insn_template::THUMB16_TYPE:
|
||
if (i == 0)
|
||
this->entry_in_thumb_mode_ = true;
|
||
break;
|
||
|
||
case Insn_template::THUMB32_TYPE:
|
||
if (insns[i].r_type() != elfcpp::R_ARM_NONE)
|
||
this->relocs_.push_back(Reloc(i, offset));
|
||
if (i == 0)
|
||
this->entry_in_thumb_mode_ = true;
|
||
break;
|
||
|
||
case Insn_template::ARM_TYPE:
|
||
// Handle cases where the target is encoded within the
|
||
// instruction.
|
||
if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
|
||
this->relocs_.push_back(Reloc(i, offset));
|
||
break;
|
||
|
||
case Insn_template::DATA_TYPE:
|
||
// Entry point cannot be data.
|
||
gold_assert(i != 0);
|
||
this->relocs_.push_back(Reloc(i, offset));
|
||
break;
|
||
|
||
default:
|
||
gold_unreachable();
|
||
}
|
||
offset += insn_size;
|
||
}
|
||
this->size_ = offset;
|
||
}
|
||
|
||
// Reloc_stub::Key methods.
|
||
|
||
// Dump a Key as a string for debugging.
|
||
|
||
std::string
|
||
Reloc_stub::Key::name() const
|
||
{
|
||
if (this->r_sym_ == invalid_index)
|
||
{
|
||
// Global symbol key name
|
||
// <stub-type>:<symbol name>:<addend>.
|
||
const std::string sym_name = this->u_.symbol->name();
|
||
// We need to print two hex number and two colons. So just add 100 bytes
|
||
// to the symbol name size.
|
||
size_t len = sym_name.size() + 100;
|
||
char* buffer = new char[len];
|
||
int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
|
||
sym_name.c_str(), this->addend_);
|
||
gold_assert(c > 0 && c < static_cast<int>(len));
|
||
delete[] buffer;
|
||
return std::string(buffer);
|
||
}
|
||
else
|
||
{
|
||
// local symbol key name
|
||
// <stub-type>:<object>:<r_sym>:<addend>.
|
||
const size_t len = 200;
|
||
char buffer[len];
|
||
int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
|
||
this->u_.relobj, this->r_sym_, this->addend_);
|
||
gold_assert(c > 0 && c < static_cast<int>(len));
|
||
return std::string(buffer);
|
||
}
|
||
}
|
||
|
||
// Reloc_stub methods.
|
||
|
||
// Determine the type of stub needed, if any, for a relocation of R_TYPE at
|
||
// LOCATION to DESTINATION.
|
||
// This code is based on the arm_type_of_stub function in
|
||
// bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
|
||
// class simple.
|
||
|
||
Stub_type
|
||
Reloc_stub::stub_type_for_reloc(
|
||
unsigned int r_type,
|
||
Arm_address location,
|
||
Arm_address destination,
|
||
bool target_is_thumb)
|
||
{
|
||
Stub_type stub_type = arm_stub_none;
|
||
|
||
// This is a bit ugly but we want to avoid using a templated class for
|
||
// big and little endianities.
|
||
bool may_use_blx;
|
||
bool should_force_pic_veneer;
|
||
bool thumb2;
|
||
bool thumb_only;
|
||
if (parameters->target().is_big_endian())
|
||
{
|
||
const Target_arm<true>& big_endian_target =
|
||
Target_arm<true>::default_target();
|
||
may_use_blx = big_endian_target.may_use_blx();
|
||
should_force_pic_veneer = big_endian_target.should_force_pic_veneer();
|
||
thumb2 = big_endian_target.using_thumb2();
|
||
thumb_only = big_endian_target.using_thumb_only();
|
||
}
|
||
else
|
||
{
|
||
const Target_arm<false>& little_endian_target =
|
||
Target_arm<false>::default_target();
|
||
may_use_blx = little_endian_target.may_use_blx();
|
||
should_force_pic_veneer = little_endian_target.should_force_pic_veneer();
|
||
thumb2 = little_endian_target.using_thumb2();
|
||
thumb_only = little_endian_target.using_thumb_only();
|
||
}
|
||
|
||
int64_t branch_offset = (int64_t)destination - location;
|
||
|
||
if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
|
||
{
|
||
// Handle cases where:
|
||
// - this call goes too far (different Thumb/Thumb2 max
|
||
// distance)
|
||
// - it's a Thumb->Arm call and blx is not available, or it's a
|
||
// Thumb->Arm branch (not bl). A stub is needed in this case.
|
||
if ((!thumb2
|
||
&& (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
|
||
|| (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
|
||
|| (thumb2
|
||
&& (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
|
||
|| (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
|
||
|| ((!target_is_thumb)
|
||
&& (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
|
||
|| (r_type == elfcpp::R_ARM_THM_JUMP24))))
|
||
{
|
||
if (target_is_thumb)
|
||
{
|
||
// Thumb to thumb.
|
||
if (!thumb_only)
|
||
{
|
||
stub_type = (parameters->options().shared() | should_force_pic_veneer)
|
||
// PIC stubs.
|
||
? ((may_use_blx
|
||
&& (r_type == elfcpp::R_ARM_THM_CALL))
|
||
// V5T and above. Stub starts with ARM code, so
|
||
// we must be able to switch mode before
|
||
// reaching it, which is only possible for 'bl'
|
||
// (ie R_ARM_THM_CALL relocation).
|
||
? arm_stub_long_branch_any_thumb_pic
|
||
// On V4T, use Thumb code only.
|
||
: arm_stub_long_branch_v4t_thumb_thumb_pic)
|
||
|
||
// non-PIC stubs.
|
||
: ((may_use_blx
|
||
&& (r_type == elfcpp::R_ARM_THM_CALL))
|
||
? arm_stub_long_branch_any_any // V5T and above.
|
||
: arm_stub_long_branch_v4t_thumb_thumb); // V4T.
|
||
}
|
||
else
|
||
{
|
||
stub_type = (parameters->options().shared() | should_force_pic_veneer)
|
||
? arm_stub_long_branch_thumb_only_pic // PIC stub.
|
||
: arm_stub_long_branch_thumb_only; // non-PIC stub.
|
||
}
|
||
}
|
||
else
|
||
{
|
||
// Thumb to arm.
|
||
|
||
// FIXME: We should check that the input section is from an
|
||
// object that has interwork enabled.
|
||
|
||
stub_type = (parameters->options().shared()
|
||
|| should_force_pic_veneer)
|
||
// PIC stubs.
|
||
? ((may_use_blx
|
||
&& (r_type == elfcpp::R_ARM_THM_CALL))
|
||
? arm_stub_long_branch_any_arm_pic // V5T and above.
|
||
: arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
|
||
|
||
// non-PIC stubs.
|
||
: ((may_use_blx
|
||
&& (r_type == elfcpp::R_ARM_THM_CALL))
|
||
? arm_stub_long_branch_any_any // V5T and above.
|
||
: arm_stub_long_branch_v4t_thumb_arm); // V4T.
|
||
|
||
// Handle v4t short branches.
|
||
if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
|
||
&& (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
|
||
&& (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
|
||
stub_type = arm_stub_short_branch_v4t_thumb_arm;
|
||
}
|
||
}
|
||
}
|
||
else if (r_type == elfcpp::R_ARM_CALL
|
||
|| r_type == elfcpp::R_ARM_JUMP24
|
||
|| r_type == elfcpp::R_ARM_PLT32)
|
||
{
|
||
if (target_is_thumb)
|
||
{
|
||
// Arm to thumb.
|
||
|
||
// FIXME: We should check that the input section is from an
|
||
// object that has interwork enabled.
|
||
|
||
// We have an extra 2-bytes reach because of
|
||
// the mode change (bit 24 (H) of BLX encoding).
|
||
if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
|
||
|| (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
|
||
|| ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
|
||
|| (r_type == elfcpp::R_ARM_JUMP24)
|
||
|| (r_type == elfcpp::R_ARM_PLT32))
|
||
{
|
||
stub_type = (parameters->options().shared()
|
||
|| should_force_pic_veneer)
|
||
// PIC stubs.
|
||
? (may_use_blx
|
||
? arm_stub_long_branch_any_thumb_pic// V5T and above.
|
||
: arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
|
||
|
||
// non-PIC stubs.
|
||
: (may_use_blx
|
||
? arm_stub_long_branch_any_any // V5T and above.
|
||
: arm_stub_long_branch_v4t_arm_thumb); // V4T.
|
||
}
|
||
}
|
||
else
|
||
{
|
||
// Arm to arm.
|
||
if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
|
||
|| (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
|
||
{
|
||
stub_type = (parameters->options().shared()
|
||
|| should_force_pic_veneer)
|
||
? arm_stub_long_branch_any_arm_pic // PIC stubs.
|
||
: arm_stub_long_branch_any_any; /// non-PIC.
|
||
}
|
||
}
|
||
}
|
||
|
||
return stub_type;
|
||
}
|
||
|
||
// Template to implement do_write for a specific target endianity.
|
||
|
||
template<bool big_endian>
|
||
void inline
|
||
Reloc_stub::do_fixed_endian_write(unsigned char* view,
|
||
section_size_type view_size)
|
||
{
|
||
const Stub_template* stub_template = this->stub_template();
|
||
const Insn_template* insns = stub_template->insns();
|
||
|
||
// FIXME: We do not handle BE8 encoding yet.
|
||
unsigned char* pov = view;
|
||
for (size_t i = 0; i < stub_template->insn_count(); i++)
|
||
{
|
||
switch (insns[i].type())
|
||
{
|
||
case Insn_template::THUMB16_TYPE:
|
||
// Non-zero reloc addends are only used in Cortex-A8 stubs.
|
||
gold_assert(insns[i].reloc_addend() == 0);
|
||
elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
|
||
break;
|
||
case Insn_template::THUMB32_TYPE:
|
||
{
|
||
uint32_t hi = (insns[i].data() >> 16) & 0xffff;
|
||
uint32_t lo = insns[i].data() & 0xffff;
|
||
elfcpp::Swap<16, big_endian>::writeval(pov, hi);
|
||
elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
|
||
}
|
||
break;
|
||
case Insn_template::ARM_TYPE:
|
||
case Insn_template::DATA_TYPE:
|
||
elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
|
||
break;
|
||
default:
|
||
gold_unreachable();
|
||
}
|
||
pov += insns[i].size();
|
||
}
|
||
gold_assert(static_cast<section_size_type>(pov - view) == view_size);
|
||
}
|
||
|
||
// Write a reloc stub to VIEW with endianity specified by BIG_ENDIAN.
|
||
|
||
void
|
||
Reloc_stub::do_write(unsigned char* view, section_size_type view_size,
|
||
bool big_endian)
|
||
{
|
||
if (big_endian)
|
||
this->do_fixed_endian_write<true>(view, view_size);
|
||
else
|
||
this->do_fixed_endian_write<false>(view, view_size);
|
||
}
|
||
|
||
// Stub_factory methods.
|
||
|
||
Stub_factory::Stub_factory()
|
||
{
|
||
// The instruction template sequences are declared as static
|
||
// objects and initialized first time the constructor runs.
|
||
|
||
// Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
|
||
// to reach the stub if necessary.
|
||
static const Insn_template elf32_arm_stub_long_branch_any_any[] =
|
||
{
|
||
Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
|
||
Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
|
||
// dcd R_ARM_ABS32(X)
|
||
};
|
||
|
||
// V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
|
||
// available.
|
||
static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
|
||
{
|
||
Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
|
||
Insn_template::arm_insn(0xe12fff1c), // bx ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
|
||
// dcd R_ARM_ABS32(X)
|
||
};
|
||
|
||
// Thumb -> Thumb long branch stub. Used on M-profile architectures.
|
||
static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
|
||
{
|
||
Insn_template::thumb16_insn(0xb401), // push {r0}
|
||
Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
|
||
Insn_template::thumb16_insn(0x4684), // mov ip, r0
|
||
Insn_template::thumb16_insn(0xbc01), // pop {r0}
|
||
Insn_template::thumb16_insn(0x4760), // bx ip
|
||
Insn_template::thumb16_insn(0xbf00), // nop
|
||
Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
|
||
// dcd R_ARM_ABS32(X)
|
||
};
|
||
|
||
// V4T Thumb -> Thumb long branch stub. Using the stack is not
|
||
// allowed.
|
||
static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
|
||
{
|
||
Insn_template::thumb16_insn(0x4778), // bx pc
|
||
Insn_template::thumb16_insn(0x46c0), // nop
|
||
Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
|
||
Insn_template::arm_insn(0xe12fff1c), // bx ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
|
||
// dcd R_ARM_ABS32(X)
|
||
};
|
||
|
||
// V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
|
||
// available.
|
||
static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
|
||
{
|
||
Insn_template::thumb16_insn(0x4778), // bx pc
|
||
Insn_template::thumb16_insn(0x46c0), // nop
|
||
Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
|
||
Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
|
||
// dcd R_ARM_ABS32(X)
|
||
};
|
||
|
||
// V4T Thumb -> ARM short branch stub. Shorter variant of the above
|
||
// one, when the destination is close enough.
|
||
static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
|
||
{
|
||
Insn_template::thumb16_insn(0x4778), // bx pc
|
||
Insn_template::thumb16_insn(0x46c0), // nop
|
||
Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
|
||
};
|
||
|
||
// ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
|
||
// blx to reach the stub if necessary.
|
||
static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
|
||
{
|
||
Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
|
||
Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
|
||
// dcd R_ARM_REL32(X-4)
|
||
};
|
||
|
||
// ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
|
||
// blx to reach the stub if necessary. We can not add into pc;
|
||
// it is not guaranteed to mode switch (different in ARMv6 and
|
||
// ARMv7).
|
||
static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
|
||
{
|
||
Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
|
||
Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
|
||
Insn_template::arm_insn(0xe12fff1c), // bx ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
|
||
// dcd R_ARM_REL32(X)
|
||
};
|
||
|
||
// V4T ARM -> ARM long branch stub, PIC.
|
||
static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
|
||
{
|
||
Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
|
||
Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
|
||
Insn_template::arm_insn(0xe12fff1c), // bx ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
|
||
// dcd R_ARM_REL32(X)
|
||
};
|
||
|
||
// V4T Thumb -> ARM long branch stub, PIC.
|
||
static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
|
||
{
|
||
Insn_template::thumb16_insn(0x4778), // bx pc
|
||
Insn_template::thumb16_insn(0x46c0), // nop
|
||
Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
|
||
Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
|
||
Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
|
||
// dcd R_ARM_REL32(X)
|
||
};
|
||
|
||
// Thumb -> Thumb long branch stub, PIC. Used on M-profile
|
||
// architectures.
|
||
static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
|
||
{
|
||
Insn_template::thumb16_insn(0xb401), // push {r0}
|
||
Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
|
||
Insn_template::thumb16_insn(0x46fc), // mov ip, pc
|
||
Insn_template::thumb16_insn(0x4484), // add ip, r0
|
||
Insn_template::thumb16_insn(0xbc01), // pop {r0}
|
||
Insn_template::thumb16_insn(0x4760), // bx ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
|
||
// dcd R_ARM_REL32(X)
|
||
};
|
||
|
||
// V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
|
||
// allowed.
|
||
static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
|
||
{
|
||
Insn_template::thumb16_insn(0x4778), // bx pc
|
||
Insn_template::thumb16_insn(0x46c0), // nop
|
||
Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
|
||
Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
|
||
Insn_template::arm_insn(0xe12fff1c), // bx ip
|
||
Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
|
||
// dcd R_ARM_REL32(X)
|
||
};
|
||
|
||
// Cortex-A8 erratum-workaround stubs.
|
||
|
||
// Stub used for conditional branches (which may be beyond +/-1MB away,
|
||
// so we can't use a conditional branch to reach this stub).
|
||
|
||
// original code:
|
||
//
|
||
// b<cond> X
|
||
// after:
|
||
//
|
||
static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
|
||
{
|
||
Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
|
||
Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
|
||
Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
|
||
// b.w X
|
||
};
|
||
|
||
// Stub used for b.w and bl.w instructions.
|
||
|
||
static const Insn_template elf32_arm_stub_a8_veneer_b[] =
|
||
{
|
||
Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
|
||
};
|
||
|
||
static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
|
||
{
|
||
Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
|
||
};
|
||
|
||
// Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
|
||
// instruction (which switches to ARM mode) to point to this stub. Jump to
|
||
// the real destination using an ARM-mode branch.
|
||
const Insn_template elf32_arm_stub_a8_veneer_blx[] =
|
||
{
|
||
Insn_template::arm_rel_insn(0xea000000, -8) // b dest
|
||
};
|
||
|
||
// Fill in the stub template look-up table. Stub templates are constructed
|
||
// per instance of Stub_factory for fast look-up without locking
|
||
// in a thread-enabled environment.
|
||
|
||
this->stub_templates_[arm_stub_none] =
|
||
new Stub_template(arm_stub_none, NULL, 0);
|
||
|
||
#define DEF_STUB(x) \
|
||
do \
|
||
{ \
|
||
size_t array_size \
|
||
= sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
|
||
Stub_type type = arm_stub_##x; \
|
||
this->stub_templates_[type] = \
|
||
new Stub_template(type, elf32_arm_stub_##x, array_size); \
|
||
} \
|
||
while (0);
|
||
|
||
DEF_STUBS
|
||
#undef DEF_STUB
|
||
}
|
||
|
||
// Stub_table methods.
|
||
|
||
// Add a STUB with using KEY. Caller is reponsible for avoid adding
|
||
// if already a STUB with the same key has been added.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Stub_table<big_endian>::add_reloc_stub(
|
||
Reloc_stub* stub,
|
||
const Reloc_stub::Key& key)
|
||
{
|
||
const Stub_template* stub_template = stub->stub_template();
|
||
gold_assert(stub_template->type() == key.stub_type());
|
||
this->reloc_stubs_[key] = stub;
|
||
if (this->addralign_ < stub_template->alignment())
|
||
this->addralign_ = stub_template->alignment();
|
||
this->has_been_changed_ = true;
|
||
}
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Stub_table<big_endian>::relocate_stubs(
|
||
const Relocate_info<32, big_endian>* relinfo,
|
||
Target_arm<big_endian>* arm_target,
|
||
Output_section* output_section,
|
||
unsigned char* view,
|
||
Arm_address address,
|
||
section_size_type view_size)
|
||
{
|
||
// If we are passed a view bigger than the stub table's. we need to
|
||
// adjust the view.
|
||
gold_assert(address == this->address()
|
||
&& (view_size
|
||
== static_cast<section_size_type>(this->data_size())));
|
||
|
||
for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
|
||
p != this->reloc_stubs_.end();
|
||
++p)
|
||
{
|
||
Reloc_stub* stub = p->second;
|
||
const Stub_template* stub_template = stub->stub_template();
|
||
if (stub_template->reloc_count() != 0)
|
||
{
|
||
// Adjust view to cover the stub only.
|
||
section_size_type offset = stub->offset();
|
||
section_size_type stub_size = stub_template->size();
|
||
gold_assert(offset + stub_size <= view_size);
|
||
|
||
arm_target->relocate_stub(stub, relinfo, output_section,
|
||
view + offset, address + offset,
|
||
stub_size);
|
||
}
|
||
}
|
||
}
|
||
|
||
// Reset address and file offset.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Stub_table<big_endian>::do_reset_address_and_file_offset()
|
||
{
|
||
off_t off = 0;
|
||
uint64_t max_addralign = 1;
|
||
for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
|
||
p != this->reloc_stubs_.end();
|
||
++p)
|
||
{
|
||
Reloc_stub* stub = p->second;
|
||
const Stub_template* stub_template = stub->stub_template();
|
||
uint64_t stub_addralign = stub_template->alignment();
|
||
max_addralign = std::max(max_addralign, stub_addralign);
|
||
off = align_address(off, stub_addralign);
|
||
stub->set_offset(off);
|
||
stub->reset_destination_address();
|
||
off += stub_template->size();
|
||
}
|
||
|
||
this->addralign_ = max_addralign;
|
||
this->set_current_data_size_for_child(off);
|
||
}
|
||
|
||
// Write out the stubs to file.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Stub_table<big_endian>::do_write(Output_file* of)
|
||
{
|
||
off_t offset = this->offset();
|
||
const section_size_type oview_size =
|
||
convert_to_section_size_type(this->data_size());
|
||
unsigned char* const oview = of->get_output_view(offset, oview_size);
|
||
|
||
for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
|
||
p != this->reloc_stubs_.end();
|
||
++p)
|
||
{
|
||
Reloc_stub* stub = p->second;
|
||
Arm_address address = this->address() + stub->offset();
|
||
gold_assert(address
|
||
== align_address(address,
|
||
stub->stub_template()->alignment()));
|
||
stub->write(oview + stub->offset(), stub->stub_template()->size(),
|
||
big_endian);
|
||
}
|
||
of->write_output_view(this->offset(), oview_size, oview);
|
||
}
|
||
|
||
// Arm_input_section methods.
|
||
|
||
// Initialize an Arm_input_section.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Arm_input_section<big_endian>::init()
|
||
{
|
||
Relobj* relobj = this->relobj();
|
||
unsigned int shndx = this->shndx();
|
||
|
||
// Cache these to speed up size and alignment queries. It is too slow
|
||
// to call section_addraglin and section_size every time.
|
||
this->original_addralign_ = relobj->section_addralign(shndx);
|
||
this->original_size_ = relobj->section_size(shndx);
|
||
|
||
// We want to make this look like the original input section after
|
||
// output sections are finalized.
|
||
Output_section* os = relobj->output_section(shndx);
|
||
off_t offset = relobj->output_section_offset(shndx);
|
||
gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
|
||
this->set_address(os->address() + offset);
|
||
this->set_file_offset(os->offset() + offset);
|
||
|
||
this->set_current_data_size(this->original_size_);
|
||
this->finalize_data_size();
|
||
}
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Arm_input_section<big_endian>::do_write(Output_file* of)
|
||
{
|
||
// We have to write out the original section content.
|
||
section_size_type section_size;
|
||
const unsigned char* section_contents =
|
||
this->relobj()->section_contents(this->shndx(), §ion_size, false);
|
||
of->write(this->offset(), section_contents, section_size);
|
||
|
||
// If this owns a stub table and it is not empty, write it.
|
||
if (this->is_stub_table_owner() && !this->stub_table_->empty())
|
||
this->stub_table_->write(of);
|
||
}
|
||
|
||
// Finalize data size.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Arm_input_section<big_endian>::set_final_data_size()
|
||
{
|
||
// If this owns a stub table, finalize its data size as well.
|
||
if (this->is_stub_table_owner())
|
||
{
|
||
uint64_t address = this->address();
|
||
|
||
// The stub table comes after the original section contents.
|
||
address += this->original_size_;
|
||
address = align_address(address, this->stub_table_->addralign());
|
||
off_t offset = this->offset() + (address - this->address());
|
||
this->stub_table_->set_address_and_file_offset(address, offset);
|
||
address += this->stub_table_->data_size();
|
||
gold_assert(address == this->address() + this->current_data_size());
|
||
}
|
||
|
||
this->set_data_size(this->current_data_size());
|
||
}
|
||
|
||
// Reset address and file offset.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Arm_input_section<big_endian>::do_reset_address_and_file_offset()
|
||
{
|
||
// Size of the original input section contents.
|
||
off_t off = convert_types<off_t, uint64_t>(this->original_size_);
|
||
|
||
// If this is a stub table owner, account for the stub table size.
|
||
if (this->is_stub_table_owner())
|
||
{
|
||
Stub_table<big_endian>* stub_table = this->stub_table_;
|
||
|
||
// Reset the stub table's address and file offset. The
|
||
// current data size for child will be updated after that.
|
||
stub_table_->reset_address_and_file_offset();
|
||
off = align_address(off, stub_table_->addralign());
|
||
off += stub_table->current_data_size();
|
||
}
|
||
|
||
this->set_current_data_size(off);
|
||
}
|
||
|
||
// Arm_output_section methods.
|
||
|
||
// Create a stub group for input sections from BEGIN to END. OWNER
|
||
// points to the input section to be the owner a new stub table.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Arm_output_section<big_endian>::create_stub_group(
|
||
Input_section_list::const_iterator begin,
|
||
Input_section_list::const_iterator end,
|
||
Input_section_list::const_iterator owner,
|
||
Target_arm<big_endian>* target,
|
||
std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
|
||
{
|
||
// Currently we convert ordinary input sections into relaxed sections only
|
||
// at this point but we may want to support creating relaxed input section
|
||
// very early. So we check here to see if owner is already a relaxed
|
||
// section.
|
||
|
||
Arm_input_section<big_endian>* arm_input_section;
|
||
if (owner->is_relaxed_input_section())
|
||
{
|
||
arm_input_section =
|
||
Arm_input_section<big_endian>::as_arm_input_section(
|
||
owner->relaxed_input_section());
|
||
}
|
||
else
|
||
{
|
||
gold_assert(owner->is_input_section());
|
||
// Create a new relaxed input section.
|
||
arm_input_section =
|
||
target->new_arm_input_section(owner->relobj(), owner->shndx());
|
||
new_relaxed_sections->push_back(arm_input_section);
|
||
}
|
||
|
||
// Create a stub table.
|
||
Stub_table<big_endian>* stub_table =
|
||
target->new_stub_table(arm_input_section);
|
||
|
||
arm_input_section->set_stub_table(stub_table);
|
||
|
||
Input_section_list::const_iterator p = begin;
|
||
Input_section_list::const_iterator prev_p;
|
||
|
||
// Look for input sections or relaxed input sections in [begin ... end].
|
||
do
|
||
{
|
||
if (p->is_input_section() || p->is_relaxed_input_section())
|
||
{
|
||
// The stub table information for input sections live
|
||
// in their objects.
|
||
Arm_relobj<big_endian>* arm_relobj =
|
||
Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
|
||
arm_relobj->set_stub_table(p->shndx(), stub_table);
|
||
}
|
||
prev_p = p++;
|
||
}
|
||
while (prev_p != end);
|
||
}
|
||
|
||
// Group input sections for stub generation. GROUP_SIZE is roughly the limit
|
||
// of stub groups. We grow a stub group by adding input section until the
|
||
// size is just below GROUP_SIZE. The last input section will be converted
|
||
// into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
|
||
// input section after the stub table, effectively double the group size.
|
||
//
|
||
// This is similar to the group_sections() function in elf32-arm.c but is
|
||
// implemented differently.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Arm_output_section<big_endian>::group_sections(
|
||
section_size_type group_size,
|
||
bool stubs_always_after_branch,
|
||
Target_arm<big_endian>* target)
|
||
{
|
||
// We only care about sections containing code.
|
||
if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
|
||
return;
|
||
|
||
// States for grouping.
|
||
typedef enum
|
||
{
|
||
// No group is being built.
|
||
NO_GROUP,
|
||
// A group is being built but the stub table is not found yet.
|
||
// We keep group a stub group until the size is just under GROUP_SIZE.
|
||
// The last input section in the group will be used as the stub table.
|
||
FINDING_STUB_SECTION,
|
||
// A group is being built and we have already found a stub table.
|
||
// We enter this state to grow a stub group by adding input section
|
||
// after the stub table. This effectively doubles the group size.
|
||
HAS_STUB_SECTION
|
||
} State;
|
||
|
||
// Any newly created relaxed sections are stored here.
|
||
std::vector<Output_relaxed_input_section*> new_relaxed_sections;
|
||
|
||
State state = NO_GROUP;
|
||
section_size_type off = 0;
|
||
section_size_type group_begin_offset = 0;
|
||
section_size_type group_end_offset = 0;
|
||
section_size_type stub_table_end_offset = 0;
|
||
Input_section_list::const_iterator group_begin =
|
||
this->input_sections().end();
|
||
Input_section_list::const_iterator stub_table =
|
||
this->input_sections().end();
|
||
Input_section_list::const_iterator group_end = this->input_sections().end();
|
||
for (Input_section_list::const_iterator p = this->input_sections().begin();
|
||
p != this->input_sections().end();
|
||
++p)
|
||
{
|
||
section_size_type section_begin_offset =
|
||
align_address(off, p->addralign());
|
||
section_size_type section_end_offset =
|
||
section_begin_offset + p->data_size();
|
||
|
||
// Check to see if we should group the previously seens sections.
|
||
switch(state)
|
||
{
|
||
case NO_GROUP:
|
||
break;
|
||
|
||
case FINDING_STUB_SECTION:
|
||
// Adding this section makes the group larger than GROUP_SIZE.
|
||
if (section_end_offset - group_begin_offset >= group_size)
|
||
{
|
||
if (stubs_always_after_branch)
|
||
{
|
||
gold_assert(group_end != this->input_sections().end());
|
||
this->create_stub_group(group_begin, group_end, group_end,
|
||
target, &new_relaxed_sections);
|
||
state = NO_GROUP;
|
||
}
|
||
else
|
||
{
|
||
// But wait, there's more! Input sections up to
|
||
// stub_group_size bytes after the stub table can be
|
||
// handled by it too.
|
||
state = HAS_STUB_SECTION;
|
||
stub_table = group_end;
|
||
stub_table_end_offset = group_end_offset;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case HAS_STUB_SECTION:
|
||
// Adding this section makes the post stub-section group larger
|
||
// than GROUP_SIZE.
|
||
if (section_end_offset - stub_table_end_offset >= group_size)
|
||
{
|
||
gold_assert(group_end != this->input_sections().end());
|
||
this->create_stub_group(group_begin, group_end, stub_table,
|
||
target, &new_relaxed_sections);
|
||
state = NO_GROUP;
|
||
}
|
||
break;
|
||
|
||
default:
|
||
gold_unreachable();
|
||
}
|
||
|
||
// If we see an input section and currently there is no group, start
|
||
// a new one. Skip any empty sections.
|
||
if ((p->is_input_section() || p->is_relaxed_input_section())
|
||
&& (p->relobj()->section_size(p->shndx()) != 0))
|
||
{
|
||
if (state == NO_GROUP)
|
||
{
|
||
state = FINDING_STUB_SECTION;
|
||
group_begin = p;
|
||
group_begin_offset = section_begin_offset;
|
||
}
|
||
|
||
// Keep track of the last input section seen.
|
||
group_end = p;
|
||
group_end_offset = section_end_offset;
|
||
}
|
||
|
||
off = section_end_offset;
|
||
}
|
||
|
||
// Create a stub group for any ungrouped sections.
|
||
if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
|
||
{
|
||
gold_assert(group_end != this->input_sections().end());
|
||
this->create_stub_group(group_begin, group_end,
|
||
(state == FINDING_STUB_SECTION
|
||
? group_end
|
||
: stub_table),
|
||
target, &new_relaxed_sections);
|
||
}
|
||
|
||
// Convert input section into relaxed input section in a batch.
|
||
if (!new_relaxed_sections.empty())
|
||
this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
|
||
|
||
// Update the section offsets
|
||
for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
|
||
{
|
||
Arm_relobj<big_endian>* arm_relobj =
|
||
Arm_relobj<big_endian>::as_arm_relobj(
|
||
new_relaxed_sections[i]->relobj());
|
||
unsigned int shndx = new_relaxed_sections[i]->shndx();
|
||
// Tell Arm_relobj that this input section is converted.
|
||
arm_relobj->convert_input_section_to_relaxed_section(shndx);
|
||
}
|
||
}
|
||
|
||
// A class to handle the PLT data.
|
||
|
||
template<bool big_endian>
|
||
class Output_data_plt_arm : public Output_section_data
|
||
{
|
||
public:
|
||
typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
|
||
Reloc_section;
|
||
|
||
Output_data_plt_arm(Layout*, Output_data_space*);
|
||
|
||
// Add an entry to the PLT.
|
||
void
|
||
add_entry(Symbol* gsym);
|
||
|
||
// Return the .rel.plt section data.
|
||
const Reloc_section*
|
||
rel_plt() const
|
||
{ return this->rel_; }
|
||
|
||
protected:
|
||
void
|
||
do_adjust_output_section(Output_section* os);
|
||
|
||
// Write to a map file.
|
||
void
|
||
do_print_to_mapfile(Mapfile* mapfile) const
|
||
{ mapfile->print_output_data(this, _("** PLT")); }
|
||
|
||
private:
|
||
// Template for the first PLT entry.
|
||
static const uint32_t first_plt_entry[5];
|
||
|
||
// Template for subsequent PLT entries.
|
||
static const uint32_t plt_entry[3];
|
||
|
||
// Set the final size.
|
||
void
|
||
set_final_data_size()
|
||
{
|
||
this->set_data_size(sizeof(first_plt_entry)
|
||
+ this->count_ * sizeof(plt_entry));
|
||
}
|
||
|
||
// Write out the PLT data.
|
||
void
|
||
do_write(Output_file*);
|
||
|
||
// The reloc section.
|
||
Reloc_section* rel_;
|
||
// The .got.plt section.
|
||
Output_data_space* got_plt_;
|
||
// The number of PLT entries.
|
||
unsigned int count_;
|
||
};
|
||
|
||
// Create the PLT section. The ordinary .got section is an argument,
|
||
// since we need to refer to the start. We also create our own .got
|
||
// section just for PLT entries.
|
||
|
||
template<bool big_endian>
|
||
Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
|
||
Output_data_space* got_plt)
|
||
: Output_section_data(4), got_plt_(got_plt), count_(0)
|
||
{
|
||
this->rel_ = new Reloc_section(false);
|
||
layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
|
||
elfcpp::SHF_ALLOC, this->rel_);
|
||
}
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
|
||
{
|
||
os->set_entsize(0);
|
||
}
|
||
|
||
// Add an entry to the PLT.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
|
||
{
|
||
gold_assert(!gsym->has_plt_offset());
|
||
|
||
// Note that when setting the PLT offset we skip the initial
|
||
// reserved PLT entry.
|
||
gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
|
||
+ sizeof(first_plt_entry));
|
||
|
||
++this->count_;
|
||
|
||
section_offset_type got_offset = this->got_plt_->current_data_size();
|
||
|
||
// Every PLT entry needs a GOT entry which points back to the PLT
|
||
// entry (this will be changed by the dynamic linker, normally
|
||
// lazily when the function is called).
|
||
this->got_plt_->set_current_data_size(got_offset + 4);
|
||
|
||
// Every PLT entry needs a reloc.
|
||
gsym->set_needs_dynsym_entry();
|
||
this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
|
||
got_offset);
|
||
|
||
// Note that we don't need to save the symbol. The contents of the
|
||
// PLT are independent of which symbols are used. The symbols only
|
||
// appear in the relocations.
|
||
}
|
||
|
||
// ARM PLTs.
|
||
// FIXME: This is not very flexible. Right now this has only been tested
|
||
// on armv5te. If we are to support additional architecture features like
|
||
// Thumb-2 or BE8, we need to make this more flexible like GNU ld.
|
||
|
||
// The first entry in the PLT.
|
||
template<bool big_endian>
|
||
const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
|
||
{
|
||
0xe52de004, // str lr, [sp, #-4]!
|
||
0xe59fe004, // ldr lr, [pc, #4]
|
||
0xe08fe00e, // add lr, pc, lr
|
||
0xe5bef008, // ldr pc, [lr, #8]!
|
||
0x00000000, // &GOT[0] - .
|
||
};
|
||
|
||
// Subsequent entries in the PLT.
|
||
|
||
template<bool big_endian>
|
||
const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
|
||
{
|
||
0xe28fc600, // add ip, pc, #0xNN00000
|
||
0xe28cca00, // add ip, ip, #0xNN000
|
||
0xe5bcf000, // ldr pc, [ip, #0xNNN]!
|
||
};
|
||
|
||
// Write out the PLT. This uses the hand-coded instructions above,
|
||
// and adjusts them as needed. This is all specified by the arm ELF
|
||
// Processor Supplement.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Output_data_plt_arm<big_endian>::do_write(Output_file* of)
|
||
{
|
||
const off_t offset = this->offset();
|
||
const section_size_type oview_size =
|
||
convert_to_section_size_type(this->data_size());
|
||
unsigned char* const oview = of->get_output_view(offset, oview_size);
|
||
|
||
const off_t got_file_offset = this->got_plt_->offset();
|
||
const section_size_type got_size =
|
||
convert_to_section_size_type(this->got_plt_->data_size());
|
||
unsigned char* const got_view = of->get_output_view(got_file_offset,
|
||
got_size);
|
||
unsigned char* pov = oview;
|
||
|
||
elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
|
||
elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
|
||
|
||
// Write first PLT entry. All but the last word are constants.
|
||
const size_t num_first_plt_words = (sizeof(first_plt_entry)
|
||
/ sizeof(plt_entry[0]));
|
||
for (size_t i = 0; i < num_first_plt_words - 1; i++)
|
||
elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
|
||
// Last word in first PLT entry is &GOT[0] - .
|
||
elfcpp::Swap<32, big_endian>::writeval(pov + 16,
|
||
got_address - (plt_address + 16));
|
||
pov += sizeof(first_plt_entry);
|
||
|
||
unsigned char* got_pov = got_view;
|
||
|
||
memset(got_pov, 0, 12);
|
||
got_pov += 12;
|
||
|
||
const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
|
||
unsigned int plt_offset = sizeof(first_plt_entry);
|
||
unsigned int plt_rel_offset = 0;
|
||
unsigned int got_offset = 12;
|
||
const unsigned int count = this->count_;
|
||
for (unsigned int i = 0;
|
||
i < count;
|
||
++i,
|
||
pov += sizeof(plt_entry),
|
||
got_pov += 4,
|
||
plt_offset += sizeof(plt_entry),
|
||
plt_rel_offset += rel_size,
|
||
got_offset += 4)
|
||
{
|
||
// Set and adjust the PLT entry itself.
|
||
int32_t offset = ((got_address + got_offset)
|
||
- (plt_address + plt_offset + 8));
|
||
|
||
gold_assert(offset >= 0 && offset < 0x0fffffff);
|
||
uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
|
||
elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
|
||
uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
|
||
elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
|
||
uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
|
||
elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
|
||
|
||
// Set the entry in the GOT.
|
||
elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
|
||
}
|
||
|
||
gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
|
||
gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
|
||
|
||
of->write_output_view(offset, oview_size, oview);
|
||
of->write_output_view(got_file_offset, got_size, got_view);
|
||
}
|
||
|
||
// Create a PLT entry for a global symbol.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
|
||
Symbol* gsym)
|
||
{
|
||
if (gsym->has_plt_offset())
|
||
return;
|
||
|
||
if (this->plt_ == NULL)
|
||
{
|
||
// Create the GOT sections first.
|
||
this->got_section(symtab, layout);
|
||
|
||
this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
|
||
layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
|
||
(elfcpp::SHF_ALLOC
|
||
| elfcpp::SHF_EXECINSTR),
|
||
this->plt_);
|
||
}
|
||
this->plt_->add_entry(gsym);
|
||
}
|
||
|
||
// Report an unsupported relocation against a local symbol.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::Scan::unsupported_reloc_local(
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int r_type)
|
||
{
|
||
gold_error(_("%s: unsupported reloc %u against local symbol"),
|
||
object->name().c_str(), r_type);
|
||
}
|
||
|
||
// We are about to emit a dynamic relocation of type R_TYPE. If the
|
||
// dynamic linker does not support it, issue an error. The GNU linker
|
||
// only issues a non-PIC error for an allocated read-only section.
|
||
// Here we know the section is allocated, but we don't know that it is
|
||
// read-only. But we check for all the relocation types which the
|
||
// glibc dynamic linker supports, so it seems appropriate to issue an
|
||
// error even if the section is not read-only.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
|
||
unsigned int r_type)
|
||
{
|
||
switch (r_type)
|
||
{
|
||
// These are the relocation types supported by glibc for ARM.
|
||
case elfcpp::R_ARM_RELATIVE:
|
||
case elfcpp::R_ARM_COPY:
|
||
case elfcpp::R_ARM_GLOB_DAT:
|
||
case elfcpp::R_ARM_JUMP_SLOT:
|
||
case elfcpp::R_ARM_ABS32:
|
||
case elfcpp::R_ARM_ABS32_NOI:
|
||
case elfcpp::R_ARM_PC24:
|
||
// FIXME: The following 3 types are not supported by Android's dynamic
|
||
// linker.
|
||
case elfcpp::R_ARM_TLS_DTPMOD32:
|
||
case elfcpp::R_ARM_TLS_DTPOFF32:
|
||
case elfcpp::R_ARM_TLS_TPOFF32:
|
||
return;
|
||
|
||
default:
|
||
// This prevents us from issuing more than one error per reloc
|
||
// section. But we can still wind up issuing more than one
|
||
// error per object file.
|
||
if (this->issued_non_pic_error_)
|
||
return;
|
||
object->error(_("requires unsupported dynamic reloc; "
|
||
"recompile with -fPIC"));
|
||
this->issued_non_pic_error_ = true;
|
||
return;
|
||
|
||
case elfcpp::R_ARM_NONE:
|
||
gold_unreachable();
|
||
}
|
||
}
|
||
|
||
// Scan a relocation for a local symbol.
|
||
// FIXME: This only handles a subset of relocation types used by Android
|
||
// on ARM v5te devices.
|
||
|
||
template<bool big_endian>
|
||
inline void
|
||
Target_arm<big_endian>::Scan::local(const General_options&,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Target_arm* target,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
Output_section* output_section,
|
||
const elfcpp::Rel<32, big_endian>& reloc,
|
||
unsigned int r_type,
|
||
const elfcpp::Sym<32, big_endian>&)
|
||
{
|
||
r_type = get_real_reloc_type(r_type);
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_NONE:
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS32:
|
||
case elfcpp::R_ARM_ABS32_NOI:
|
||
// If building a shared library (or a position-independent
|
||
// executable), we need to create a dynamic relocation for
|
||
// this location. The relocation applied at link time will
|
||
// apply the link-time value, so we flag the location with
|
||
// an R_ARM_RELATIVE relocation so the dynamic loader can
|
||
// relocate it easily.
|
||
if (parameters->options().output_is_position_independent())
|
||
{
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
|
||
// If we are to add more other reloc types than R_ARM_ABS32,
|
||
// we need to add check_non_pic(object, r_type) here.
|
||
rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
|
||
output_section, data_shndx,
|
||
reloc.get_r_offset());
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_REL32:
|
||
case elfcpp::R_ARM_THM_CALL:
|
||
case elfcpp::R_ARM_CALL:
|
||
case elfcpp::R_ARM_PREL31:
|
||
case elfcpp::R_ARM_JUMP24:
|
||
case elfcpp::R_ARM_PLT32:
|
||
case elfcpp::R_ARM_THM_ABS5:
|
||
case elfcpp::R_ARM_ABS8:
|
||
case elfcpp::R_ARM_ABS12:
|
||
case elfcpp::R_ARM_ABS16:
|
||
case elfcpp::R_ARM_BASE_ABS:
|
||
case elfcpp::R_ARM_MOVW_ABS_NC:
|
||
case elfcpp::R_ARM_MOVT_ABS:
|
||
case elfcpp::R_ARM_THM_MOVW_ABS_NC:
|
||
case elfcpp::R_ARM_THM_MOVT_ABS:
|
||
case elfcpp::R_ARM_MOVW_PREL_NC:
|
||
case elfcpp::R_ARM_MOVT_PREL:
|
||
case elfcpp::R_ARM_THM_MOVW_PREL_NC:
|
||
case elfcpp::R_ARM_THM_MOVT_PREL:
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOTOFF32:
|
||
// We need a GOT section:
|
||
target->got_section(symtab, layout);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_BASE_PREL:
|
||
// FIXME: What about this?
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOT_BREL:
|
||
case elfcpp::R_ARM_GOT_PREL:
|
||
{
|
||
// The symbol requires a GOT entry.
|
||
Output_data_got<32, big_endian>* got =
|
||
target->got_section(symtab, layout);
|
||
unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
|
||
if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
|
||
{
|
||
// If we are generating a shared object, we need to add a
|
||
// dynamic RELATIVE relocation for this symbol's GOT entry.
|
||
if (parameters->options().output_is_position_independent())
|
||
{
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
|
||
rel_dyn->add_local_relative(
|
||
object, r_sym, elfcpp::R_ARM_RELATIVE, got,
|
||
object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_TARGET1:
|
||
// This should have been mapped to another type already.
|
||
// Fall through.
|
||
case elfcpp::R_ARM_COPY:
|
||
case elfcpp::R_ARM_GLOB_DAT:
|
||
case elfcpp::R_ARM_JUMP_SLOT:
|
||
case elfcpp::R_ARM_RELATIVE:
|
||
// These are relocations which should only be seen by the
|
||
// dynamic linker, and should never be seen here.
|
||
gold_error(_("%s: unexpected reloc %u in object file"),
|
||
object->name().c_str(), r_type);
|
||
break;
|
||
|
||
default:
|
||
unsupported_reloc_local(object, r_type);
|
||
break;
|
||
}
|
||
}
|
||
|
||
// Report an unsupported relocation against a global symbol.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::Scan::unsupported_reloc_global(
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int r_type,
|
||
Symbol* gsym)
|
||
{
|
||
gold_error(_("%s: unsupported reloc %u against global symbol %s"),
|
||
object->name().c_str(), r_type, gsym->demangled_name().c_str());
|
||
}
|
||
|
||
// Scan a relocation for a global symbol.
|
||
// FIXME: This only handles a subset of relocation types used by Android
|
||
// on ARM v5te devices.
|
||
|
||
template<bool big_endian>
|
||
inline void
|
||
Target_arm<big_endian>::Scan::global(const General_options&,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Target_arm* target,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
Output_section* output_section,
|
||
const elfcpp::Rel<32, big_endian>& reloc,
|
||
unsigned int r_type,
|
||
Symbol* gsym)
|
||
{
|
||
r_type = get_real_reloc_type(r_type);
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_NONE:
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS32:
|
||
case elfcpp::R_ARM_ABS32_NOI:
|
||
{
|
||
// Make a dynamic relocation if necessary.
|
||
if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
|
||
{
|
||
if (target->may_need_copy_reloc(gsym))
|
||
{
|
||
target->copy_reloc(symtab, layout, object,
|
||
data_shndx, output_section, gsym, reloc);
|
||
}
|
||
else if (gsym->can_use_relative_reloc(false))
|
||
{
|
||
// If we are to add more other reloc types than R_ARM_ABS32,
|
||
// we need to add check_non_pic(object, r_type) here.
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
|
||
output_section, object,
|
||
data_shndx, reloc.get_r_offset());
|
||
}
|
||
else
|
||
{
|
||
// If we are to add more other reloc types than R_ARM_ABS32,
|
||
// we need to add check_non_pic(object, r_type) here.
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
rel_dyn->add_global(gsym, r_type, output_section, object,
|
||
data_shndx, reloc.get_r_offset());
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_MOVW_ABS_NC:
|
||
case elfcpp::R_ARM_MOVT_ABS:
|
||
case elfcpp::R_ARM_THM_MOVW_ABS_NC:
|
||
case elfcpp::R_ARM_THM_MOVT_ABS:
|
||
case elfcpp::R_ARM_MOVW_PREL_NC:
|
||
case elfcpp::R_ARM_MOVT_PREL:
|
||
case elfcpp::R_ARM_THM_MOVW_PREL_NC:
|
||
case elfcpp::R_ARM_THM_MOVT_PREL:
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_ABS5:
|
||
case elfcpp::R_ARM_ABS8:
|
||
case elfcpp::R_ARM_ABS12:
|
||
case elfcpp::R_ARM_ABS16:
|
||
case elfcpp::R_ARM_BASE_ABS:
|
||
{
|
||
// No dynamic relocs of this kinds.
|
||
// Report the error in case of PIC.
|
||
int flags = Symbol::NON_PIC_REF;
|
||
if (gsym->type() == elfcpp::STT_FUNC
|
||
|| gsym->type() == elfcpp::STT_ARM_TFUNC)
|
||
flags |= Symbol::FUNCTION_CALL;
|
||
if (gsym->needs_dynamic_reloc(flags))
|
||
check_non_pic(object, r_type);
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_REL32:
|
||
case elfcpp::R_ARM_PREL31:
|
||
{
|
||
// Make a dynamic relocation if necessary.
|
||
int flags = Symbol::NON_PIC_REF;
|
||
if (gsym->needs_dynamic_reloc(flags))
|
||
{
|
||
if (target->may_need_copy_reloc(gsym))
|
||
{
|
||
target->copy_reloc(symtab, layout, object,
|
||
data_shndx, output_section, gsym, reloc);
|
||
}
|
||
else
|
||
{
|
||
check_non_pic(object, r_type);
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
rel_dyn->add_global(gsym, r_type, output_section, object,
|
||
data_shndx, reloc.get_r_offset());
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_JUMP24:
|
||
case elfcpp::R_ARM_THM_CALL:
|
||
case elfcpp::R_ARM_CALL:
|
||
{
|
||
if (Target_arm<big_endian>::Scan::symbol_needs_plt_entry(gsym))
|
||
target->make_plt_entry(symtab, layout, gsym);
|
||
// Make a dynamic relocation if necessary.
|
||
int flags = Symbol::NON_PIC_REF;
|
||
if (gsym->type() == elfcpp::STT_FUNC
|
||
|| gsym->type() == elfcpp::STT_ARM_TFUNC)
|
||
flags |= Symbol::FUNCTION_CALL;
|
||
if (gsym->needs_dynamic_reloc(flags))
|
||
{
|
||
if (target->may_need_copy_reloc(gsym))
|
||
{
|
||
target->copy_reloc(symtab, layout, object,
|
||
data_shndx, output_section, gsym,
|
||
reloc);
|
||
}
|
||
else
|
||
{
|
||
check_non_pic(object, r_type);
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
rel_dyn->add_global(gsym, r_type, output_section, object,
|
||
data_shndx, reloc.get_r_offset());
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_PLT32:
|
||
// If the symbol is fully resolved, this is just a relative
|
||
// local reloc. Otherwise we need a PLT entry.
|
||
if (gsym->final_value_is_known())
|
||
break;
|
||
// If building a shared library, we can also skip the PLT entry
|
||
// if the symbol is defined in the output file and is protected
|
||
// or hidden.
|
||
if (gsym->is_defined()
|
||
&& !gsym->is_from_dynobj()
|
||
&& !gsym->is_preemptible())
|
||
break;
|
||
target->make_plt_entry(symtab, layout, gsym);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOTOFF32:
|
||
// We need a GOT section.
|
||
target->got_section(symtab, layout);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_BASE_PREL:
|
||
// FIXME: What about this?
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOT_BREL:
|
||
case elfcpp::R_ARM_GOT_PREL:
|
||
{
|
||
// The symbol requires a GOT entry.
|
||
Output_data_got<32, big_endian>* got =
|
||
target->got_section(symtab, layout);
|
||
if (gsym->final_value_is_known())
|
||
got->add_global(gsym, GOT_TYPE_STANDARD);
|
||
else
|
||
{
|
||
// If this symbol is not fully resolved, we need to add a
|
||
// GOT entry with a dynamic relocation.
|
||
Reloc_section* rel_dyn = target->rel_dyn_section(layout);
|
||
if (gsym->is_from_dynobj()
|
||
|| gsym->is_undefined()
|
||
|| gsym->is_preemptible())
|
||
got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
|
||
rel_dyn, elfcpp::R_ARM_GLOB_DAT);
|
||
else
|
||
{
|
||
if (got->add_global(gsym, GOT_TYPE_STANDARD))
|
||
rel_dyn->add_global_relative(
|
||
gsym, elfcpp::R_ARM_RELATIVE, got,
|
||
gsym->got_offset(GOT_TYPE_STANDARD));
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_TARGET1:
|
||
// This should have been mapped to another type already.
|
||
// Fall through.
|
||
case elfcpp::R_ARM_COPY:
|
||
case elfcpp::R_ARM_GLOB_DAT:
|
||
case elfcpp::R_ARM_JUMP_SLOT:
|
||
case elfcpp::R_ARM_RELATIVE:
|
||
// These are relocations which should only be seen by the
|
||
// dynamic linker, and should never be seen here.
|
||
gold_error(_("%s: unexpected reloc %u in object file"),
|
||
object->name().c_str(), r_type);
|
||
break;
|
||
|
||
default:
|
||
unsupported_reloc_global(object, r_type, gsym);
|
||
break;
|
||
}
|
||
}
|
||
|
||
// Process relocations for gc.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::gc_process_relocs(const General_options& options,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
unsigned int,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
size_t local_symbol_count,
|
||
const unsigned char* plocal_symbols)
|
||
{
|
||
typedef Target_arm<big_endian> Arm;
|
||
typedef typename Target_arm<big_endian>::Scan Scan;
|
||
|
||
gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
|
||
options,
|
||
symtab,
|
||
layout,
|
||
this,
|
||
object,
|
||
data_shndx,
|
||
prelocs,
|
||
reloc_count,
|
||
output_section,
|
||
needs_special_offset_handling,
|
||
local_symbol_count,
|
||
plocal_symbols);
|
||
}
|
||
|
||
// Scan relocations for a section.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::scan_relocs(const General_options& options,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
size_t local_symbol_count,
|
||
const unsigned char* plocal_symbols)
|
||
{
|
||
typedef typename Target_arm<big_endian>::Scan Scan;
|
||
if (sh_type == elfcpp::SHT_RELA)
|
||
{
|
||
gold_error(_("%s: unsupported RELA reloc section"),
|
||
object->name().c_str());
|
||
return;
|
||
}
|
||
|
||
gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
|
||
options,
|
||
symtab,
|
||
layout,
|
||
this,
|
||
object,
|
||
data_shndx,
|
||
prelocs,
|
||
reloc_count,
|
||
output_section,
|
||
needs_special_offset_handling,
|
||
local_symbol_count,
|
||
plocal_symbols);
|
||
}
|
||
|
||
// Finalize the sections.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::do_finalize_sections(Layout* layout)
|
||
{
|
||
// Fill in some more dynamic tags.
|
||
Output_data_dynamic* const odyn = layout->dynamic_data();
|
||
if (odyn != NULL)
|
||
{
|
||
if (this->got_plt_ != NULL)
|
||
odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
|
||
|
||
if (this->plt_ != NULL)
|
||
{
|
||
const Output_data* od = this->plt_->rel_plt();
|
||
odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
|
||
odyn->add_section_address(elfcpp::DT_JMPREL, od);
|
||
odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
|
||
}
|
||
|
||
if (this->rel_dyn_ != NULL)
|
||
{
|
||
const Output_data* od = this->rel_dyn_;
|
||
odyn->add_section_address(elfcpp::DT_REL, od);
|
||
odyn->add_section_size(elfcpp::DT_RELSZ, od);
|
||
odyn->add_constant(elfcpp::DT_RELENT,
|
||
elfcpp::Elf_sizes<32>::rel_size);
|
||
}
|
||
|
||
if (!parameters->options().shared())
|
||
{
|
||
// The value of the DT_DEBUG tag is filled in by the dynamic
|
||
// linker at run time, and used by the debugger.
|
||
odyn->add_constant(elfcpp::DT_DEBUG, 0);
|
||
}
|
||
}
|
||
|
||
// Emit any relocs we saved in an attempt to avoid generating COPY
|
||
// relocs.
|
||
if (this->copy_relocs_.any_saved_relocs())
|
||
this->copy_relocs_.emit(this->rel_dyn_section(layout));
|
||
|
||
// For the ARM target, we need to add a PT_ARM_EXIDX segment for
|
||
// the .ARM.exidx section.
|
||
if (!layout->script_options()->saw_phdrs_clause()
|
||
&& !parameters->options().relocatable())
|
||
{
|
||
Output_section* exidx_section =
|
||
layout->find_output_section(".ARM.exidx");
|
||
|
||
if (exidx_section != NULL
|
||
&& exidx_section->type() == elfcpp::SHT_ARM_EXIDX)
|
||
{
|
||
gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
|
||
== NULL);
|
||
Output_segment* exidx_segment =
|
||
layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
|
||
exidx_segment->add_output_section(exidx_section, elfcpp::PF_R);
|
||
}
|
||
}
|
||
}
|
||
|
||
// Return whether a direct absolute static relocation needs to be applied.
|
||
// In cases where Scan::local() or Scan::global() has created
|
||
// a dynamic relocation other than R_ARM_RELATIVE, the addend
|
||
// of the relocation is carried in the data, and we must not
|
||
// apply the static relocation.
|
||
|
||
template<bool big_endian>
|
||
inline bool
|
||
Target_arm<big_endian>::Relocate::should_apply_static_reloc(
|
||
const Sized_symbol<32>* gsym,
|
||
int ref_flags,
|
||
bool is_32bit,
|
||
Output_section* output_section)
|
||
{
|
||
// If the output section is not allocated, then we didn't call
|
||
// scan_relocs, we didn't create a dynamic reloc, and we must apply
|
||
// the reloc here.
|
||
if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
|
||
return true;
|
||
|
||
// For local symbols, we will have created a non-RELATIVE dynamic
|
||
// relocation only if (a) the output is position independent,
|
||
// (b) the relocation is absolute (not pc- or segment-relative), and
|
||
// (c) the relocation is not 32 bits wide.
|
||
if (gsym == NULL)
|
||
return !(parameters->options().output_is_position_independent()
|
||
&& (ref_flags & Symbol::ABSOLUTE_REF)
|
||
&& !is_32bit);
|
||
|
||
// For global symbols, we use the same helper routines used in the
|
||
// scan pass. If we did not create a dynamic relocation, or if we
|
||
// created a RELATIVE dynamic relocation, we should apply the static
|
||
// relocation.
|
||
bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
|
||
bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
|
||
&& gsym->can_use_relative_reloc(ref_flags
|
||
& Symbol::FUNCTION_CALL);
|
||
return !has_dyn || is_rel;
|
||
}
|
||
|
||
// Perform a relocation.
|
||
|
||
template<bool big_endian>
|
||
inline bool
|
||
Target_arm<big_endian>::Relocate::relocate(
|
||
const Relocate_info<32, big_endian>* relinfo,
|
||
Target_arm* target,
|
||
Output_section *output_section,
|
||
size_t relnum,
|
||
const elfcpp::Rel<32, big_endian>& rel,
|
||
unsigned int r_type,
|
||
const Sized_symbol<32>* gsym,
|
||
const Symbol_value<32>* psymval,
|
||
unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
section_size_type /* view_size */ )
|
||
{
|
||
typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
|
||
|
||
r_type = get_real_reloc_type(r_type);
|
||
|
||
// If this the symbol may be a Thumb function, set thumb bit to 1.
|
||
bool has_thumb_bit = ((gsym != NULL)
|
||
&& (gsym->type() == elfcpp::STT_FUNC
|
||
|| gsym->type() == elfcpp::STT_ARM_TFUNC));
|
||
|
||
// Pick the value to use for symbols defined in shared objects.
|
||
Symbol_value<32> symval;
|
||
if (gsym != NULL
|
||
&& gsym->use_plt_offset(reloc_is_non_pic(r_type)))
|
||
{
|
||
symval.set_output_value(target->plt_section()->address()
|
||
+ gsym->plt_offset());
|
||
psymval = &symval;
|
||
has_thumb_bit = 0;
|
||
}
|
||
|
||
const Sized_relobj<32, big_endian>* object = relinfo->object;
|
||
|
||
// Get the GOT offset if needed.
|
||
// The GOT pointer points to the end of the GOT section.
|
||
// We need to subtract the size of the GOT section to get
|
||
// the actual offset to use in the relocation.
|
||
bool have_got_offset = false;
|
||
unsigned int got_offset = 0;
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_GOT_BREL:
|
||
case elfcpp::R_ARM_GOT_PREL:
|
||
if (gsym != NULL)
|
||
{
|
||
gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
|
||
got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
|
||
- target->got_size());
|
||
}
|
||
else
|
||
{
|
||
unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
|
||
gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
|
||
got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
|
||
- target->got_size());
|
||
}
|
||
have_got_offset = true;
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
typename Arm_relocate_functions::Status reloc_status =
|
||
Arm_relocate_functions::STATUS_OKAY;
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_NONE:
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS8:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS12:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS16:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS32:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
|
||
has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_ABS32_NOI:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
// No thumb bit for this relocation: (S + A)
|
||
reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
|
||
false);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_MOVW_ABS_NC:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::movw_abs_nc(view, object,
|
||
psymval,
|
||
has_thumb_bit);
|
||
else
|
||
gold_error(_("relocation R_ARM_MOVW_ABS_NC cannot be used when making"
|
||
"a shared object; recompile with -fPIC"));
|
||
break;
|
||
|
||
case elfcpp::R_ARM_MOVT_ABS:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::movt_abs(view, object, psymval);
|
||
else
|
||
gold_error(_("relocation R_ARM_MOVT_ABS cannot be used when making"
|
||
"a shared object; recompile with -fPIC"));
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_MOVW_ABS_NC:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::thm_movw_abs_nc(view, object,
|
||
psymval,
|
||
has_thumb_bit);
|
||
else
|
||
gold_error(_("relocation R_ARM_THM_MOVW_ABS_NC cannot be used when"
|
||
"making a shared object; recompile with -fPIC"));
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_MOVT_ABS:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::thm_movt_abs(view, object,
|
||
psymval);
|
||
else
|
||
gold_error(_("relocation R_ARM_THM_MOVT_ABS cannot be used when"
|
||
"making a shared object; recompile with -fPIC"));
|
||
break;
|
||
|
||
case elfcpp::R_ARM_MOVW_PREL_NC:
|
||
reloc_status = Arm_relocate_functions::movw_prel_nc(view, object,
|
||
psymval, address,
|
||
has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_MOVT_PREL:
|
||
reloc_status = Arm_relocate_functions::movt_prel(view, object,
|
||
psymval, address);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_MOVW_PREL_NC:
|
||
reloc_status = Arm_relocate_functions::thm_movw_prel_nc(view, object,
|
||
psymval, address,
|
||
has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_MOVT_PREL:
|
||
reloc_status = Arm_relocate_functions::thm_movt_prel(view, object,
|
||
psymval, address);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_REL32:
|
||
reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_ABS5:
|
||
if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
|
||
output_section))
|
||
reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_THM_CALL:
|
||
reloc_status = Arm_relocate_functions::thm_call(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOTOFF32:
|
||
{
|
||
elfcpp::Elf_types<32>::Elf_Addr got_origin;
|
||
got_origin = target->got_plt_section()->address();
|
||
reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
|
||
got_origin, has_thumb_bit);
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_BASE_PREL:
|
||
{
|
||
uint32_t origin;
|
||
// Get the addressing origin of the output segment defining the
|
||
// symbol gsym (AAELF 4.6.1.2 Relocation types)
|
||
gold_assert(gsym != NULL);
|
||
if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
|
||
origin = gsym->output_segment()->vaddr();
|
||
else if (gsym->source () == Symbol::IN_OUTPUT_DATA)
|
||
origin = gsym->output_data()->address();
|
||
else
|
||
{
|
||
gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
|
||
_("cannot find origin of R_ARM_BASE_PREL"));
|
||
return true;
|
||
}
|
||
reloc_status = Arm_relocate_functions::base_prel(view, origin, address);
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_BASE_ABS:
|
||
{
|
||
if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
|
||
output_section))
|
||
break;
|
||
|
||
uint32_t origin;
|
||
// Get the addressing origin of the output segment defining
|
||
// the symbol gsym (AAELF 4.6.1.2 Relocation types).
|
||
if (gsym == NULL)
|
||
// R_ARM_BASE_ABS with the NULL symbol will give the
|
||
// absolute address of the GOT origin (GOT_ORG) (see ARM IHI
|
||
// 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
|
||
origin = target->got_plt_section()->address();
|
||
else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
|
||
origin = gsym->output_segment()->vaddr();
|
||
else if (gsym->source () == Symbol::IN_OUTPUT_DATA)
|
||
origin = gsym->output_data()->address();
|
||
else
|
||
{
|
||
gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
|
||
_("cannot find origin of R_ARM_BASE_ABS"));
|
||
return true;
|
||
}
|
||
|
||
reloc_status = Arm_relocate_functions::base_abs(view, origin);
|
||
}
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOT_BREL:
|
||
gold_assert(have_got_offset);
|
||
reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_GOT_PREL:
|
||
gold_assert(have_got_offset);
|
||
// Get the address origin for GOT PLT, which is allocated right
|
||
// after the GOT section, to calculate an absolute address of
|
||
// the symbol GOT entry (got_origin + got_offset).
|
||
elfcpp::Elf_types<32>::Elf_Addr got_origin;
|
||
got_origin = target->got_plt_section()->address();
|
||
reloc_status = Arm_relocate_functions::got_prel(view,
|
||
got_origin + got_offset,
|
||
address);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_PLT32:
|
||
gold_assert(gsym == NULL
|
||
|| gsym->has_plt_offset()
|
||
|| gsym->final_value_is_known()
|
||
|| (gsym->is_defined()
|
||
&& !gsym->is_from_dynobj()
|
||
&& !gsym->is_preemptible()));
|
||
reloc_status = Arm_relocate_functions::plt32(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_CALL:
|
||
reloc_status = Arm_relocate_functions::call(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_JUMP24:
|
||
reloc_status = Arm_relocate_functions::jump24(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_PREL31:
|
||
reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
|
||
address, has_thumb_bit);
|
||
break;
|
||
|
||
case elfcpp::R_ARM_TARGET1:
|
||
// This should have been mapped to another type already.
|
||
// Fall through.
|
||
case elfcpp::R_ARM_COPY:
|
||
case elfcpp::R_ARM_GLOB_DAT:
|
||
case elfcpp::R_ARM_JUMP_SLOT:
|
||
case elfcpp::R_ARM_RELATIVE:
|
||
// These are relocations which should only be seen by the
|
||
// dynamic linker, and should never be seen here.
|
||
gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
|
||
_("unexpected reloc %u in object file"),
|
||
r_type);
|
||
break;
|
||
|
||
default:
|
||
gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
|
||
_("unsupported reloc %u"),
|
||
r_type);
|
||
break;
|
||
}
|
||
|
||
// Report any errors.
|
||
switch (reloc_status)
|
||
{
|
||
case Arm_relocate_functions::STATUS_OKAY:
|
||
break;
|
||
case Arm_relocate_functions::STATUS_OVERFLOW:
|
||
gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
|
||
_("relocation overflow in relocation %u"),
|
||
r_type);
|
||
break;
|
||
case Arm_relocate_functions::STATUS_BAD_RELOC:
|
||
gold_error_at_location(
|
||
relinfo,
|
||
relnum,
|
||
rel.get_r_offset(),
|
||
_("unexpected opcode while processing relocation %u"),
|
||
r_type);
|
||
break;
|
||
default:
|
||
gold_unreachable();
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
// Relocate section data.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::relocate_section(
|
||
const Relocate_info<32, big_endian>* relinfo,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr address,
|
||
section_size_type view_size,
|
||
const Reloc_symbol_changes* reloc_symbol_changes)
|
||
{
|
||
typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
|
||
gold_assert(sh_type == elfcpp::SHT_REL);
|
||
|
||
gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
|
||
Arm_relocate>(
|
||
relinfo,
|
||
this,
|
||
prelocs,
|
||
reloc_count,
|
||
output_section,
|
||
needs_special_offset_handling,
|
||
view,
|
||
address,
|
||
view_size,
|
||
reloc_symbol_changes);
|
||
}
|
||
|
||
// Return the size of a relocation while scanning during a relocatable
|
||
// link.
|
||
|
||
template<bool big_endian>
|
||
unsigned int
|
||
Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
|
||
unsigned int r_type,
|
||
Relobj* object)
|
||
{
|
||
r_type = get_real_reloc_type(r_type);
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_NONE:
|
||
return 0;
|
||
|
||
case elfcpp::R_ARM_ABS8:
|
||
return 1;
|
||
|
||
case elfcpp::R_ARM_ABS16:
|
||
case elfcpp::R_ARM_THM_ABS5:
|
||
return 2;
|
||
|
||
case elfcpp::R_ARM_ABS32:
|
||
case elfcpp::R_ARM_ABS32_NOI:
|
||
case elfcpp::R_ARM_ABS12:
|
||
case elfcpp::R_ARM_BASE_ABS:
|
||
case elfcpp::R_ARM_REL32:
|
||
case elfcpp::R_ARM_THM_CALL:
|
||
case elfcpp::R_ARM_GOTOFF32:
|
||
case elfcpp::R_ARM_BASE_PREL:
|
||
case elfcpp::R_ARM_GOT_BREL:
|
||
case elfcpp::R_ARM_GOT_PREL:
|
||
case elfcpp::R_ARM_PLT32:
|
||
case elfcpp::R_ARM_CALL:
|
||
case elfcpp::R_ARM_JUMP24:
|
||
case elfcpp::R_ARM_PREL31:
|
||
case elfcpp::R_ARM_MOVW_ABS_NC:
|
||
case elfcpp::R_ARM_MOVT_ABS:
|
||
case elfcpp::R_ARM_THM_MOVW_ABS_NC:
|
||
case elfcpp::R_ARM_THM_MOVT_ABS:
|
||
case elfcpp::R_ARM_MOVW_PREL_NC:
|
||
case elfcpp::R_ARM_MOVT_PREL:
|
||
case elfcpp::R_ARM_THM_MOVW_PREL_NC:
|
||
case elfcpp::R_ARM_THM_MOVT_PREL:
|
||
return 4;
|
||
|
||
case elfcpp::R_ARM_TARGET1:
|
||
// This should have been mapped to another type already.
|
||
// Fall through.
|
||
case elfcpp::R_ARM_COPY:
|
||
case elfcpp::R_ARM_GLOB_DAT:
|
||
case elfcpp::R_ARM_JUMP_SLOT:
|
||
case elfcpp::R_ARM_RELATIVE:
|
||
// These are relocations which should only be seen by the
|
||
// dynamic linker, and should never be seen here.
|
||
gold_error(_("%s: unexpected reloc %u in object file"),
|
||
object->name().c_str(), r_type);
|
||
return 0;
|
||
|
||
default:
|
||
object->error(_("unsupported reloc %u in object file"), r_type);
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
// Scan the relocs during a relocatable link.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::scan_relocatable_relocs(
|
||
const General_options& options,
|
||
Symbol_table* symtab,
|
||
Layout* layout,
|
||
Sized_relobj<32, big_endian>* object,
|
||
unsigned int data_shndx,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
bool needs_special_offset_handling,
|
||
size_t local_symbol_count,
|
||
const unsigned char* plocal_symbols,
|
||
Relocatable_relocs* rr)
|
||
{
|
||
gold_assert(sh_type == elfcpp::SHT_REL);
|
||
|
||
typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
|
||
Relocatable_size_for_reloc> Scan_relocatable_relocs;
|
||
|
||
gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
|
||
Scan_relocatable_relocs>(
|
||
options,
|
||
symtab,
|
||
layout,
|
||
object,
|
||
data_shndx,
|
||
prelocs,
|
||
reloc_count,
|
||
output_section,
|
||
needs_special_offset_handling,
|
||
local_symbol_count,
|
||
plocal_symbols,
|
||
rr);
|
||
}
|
||
|
||
// Relocate a section during a relocatable link.
|
||
|
||
template<bool big_endian>
|
||
void
|
||
Target_arm<big_endian>::relocate_for_relocatable(
|
||
const Relocate_info<32, big_endian>* relinfo,
|
||
unsigned int sh_type,
|
||
const unsigned char* prelocs,
|
||
size_t reloc_count,
|
||
Output_section* output_section,
|
||
off_t offset_in_output_section,
|
||
const Relocatable_relocs* rr,
|
||
unsigned char* view,
|
||
elfcpp::Elf_types<32>::Elf_Addr view_address,
|
||
section_size_type view_size,
|
||
unsigned char* reloc_view,
|
||
section_size_type reloc_view_size)
|
||
{
|
||
gold_assert(sh_type == elfcpp::SHT_REL);
|
||
|
||
gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
|
||
relinfo,
|
||
prelocs,
|
||
reloc_count,
|
||
output_section,
|
||
offset_in_output_section,
|
||
rr,
|
||
view,
|
||
view_address,
|
||
view_size,
|
||
reloc_view,
|
||
reloc_view_size);
|
||
}
|
||
|
||
// Return the value to use for a dynamic symbol which requires special
|
||
// treatment. This is how we support equality comparisons of function
|
||
// pointers across shared library boundaries, as described in the
|
||
// processor specific ABI supplement.
|
||
|
||
template<bool big_endian>
|
||
uint64_t
|
||
Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
|
||
{
|
||
gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
|
||
return this->plt_section()->address() + gsym->plt_offset();
|
||
}
|
||
|
||
// Map platform-specific relocs to real relocs
|
||
//
|
||
template<bool big_endian>
|
||
unsigned int
|
||
Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
|
||
{
|
||
switch (r_type)
|
||
{
|
||
case elfcpp::R_ARM_TARGET1:
|
||
// This is either R_ARM_ABS32 or R_ARM_REL32;
|
||
return elfcpp::R_ARM_ABS32;
|
||
|
||
case elfcpp::R_ARM_TARGET2:
|
||
// This can be any reloc type but ususally is R_ARM_GOT_PREL
|
||
return elfcpp::R_ARM_GOT_PREL;
|
||
|
||
default:
|
||
return r_type;
|
||
}
|
||
}
|
||
|
||
// The selector for arm object files.
|
||
|
||
template<bool big_endian>
|
||
class Target_selector_arm : public Target_selector
|
||
{
|
||
public:
|
||
Target_selector_arm()
|
||
: Target_selector(elfcpp::EM_ARM, 32, big_endian,
|
||
(big_endian ? "elf32-bigarm" : "elf32-littlearm"))
|
||
{ }
|
||
|
||
Target*
|
||
do_instantiate_target()
|
||
{ return new Target_arm<big_endian>(); }
|
||
};
|
||
|
||
Target_selector_arm<false> target_selector_arm;
|
||
Target_selector_arm<true> target_selector_armbe;
|
||
|
||
} // End anonymous namespace.
|