binutils-gdb/elfcpp/powerpc.h
Alan Modra 34e0882b83 [GOLD] PowerPC tls_get_addr_optimize
This implements the special __tls_get_addr_opt call stub for powerpc
gold that returns __thread variable addresses without actually making
a call to __tls_get_addr in most cases.  Shared libraries that are
loaded at program load time (ie. dlopen is not used) have a known
layout for their __thread variables, and thus DTPMOD64/DPTREL64 pairs
describing those variables can be set up by ld.so for the
__tls_get_addr_opt call stub fast exit.
Ref https://sourceware.org/ml/libc-alpha/2015-03/msg00626.html

I really, really wish I'd used a differently versioned __tls_get_addr
symbol than the base symbol to indicate glibc support for the
optimized call, rather than having glibc export __tls_get_addr_opt.  A
lot of the messing around here, flipping symbols from __tls_get_addr
to __tls_get_addr_opt, is caused by that decision.  About the only
benefit is that a user can see at a glance that their disassembled
code is calling __tls_get_addr via the fancy call stub..  Anyway, we
need references to __tls_get_addr to seem like they were to
__tls_get_addr_opt, and in cases like the tsan interceptor, a
definition of __tls_get_addr to seem like one of __tls_get_addr_opt
as well.  That's the reason for Symbol::clear_in_reg and
Symbol_table::clone, and why symbols are substituted in Scan::global
and other places dealing with dynamic linking.

elfcpp/
	* elfcpp.h (DT_PPC_OPT): Define.
	* powerpc.h (PPC_OPT_TLS): Define.
gold/
	* options.h (tls_get_addr_optimize): New option.
	* symtab.h (Symbol::clear_in_reg, clone): New functions.
	(Sized_symbol::clone): New function.
	(Symbol_table::clone): New function.
	* resolve.cc (Symbol::clone, Sized_symbol::clone): New functions.
	* powerpc.cc (Target_powerpc::has_tls_get_addr_opt_,
	tls_get_addr_, tls_get_addr_opt_): New vars.
	(Target_powerpc::tls_get_addr_opt, tls_get_addr,
	is_tls_get_addr_opt, replace_tls_get_addr,
	set_has_tls_get_addr_opt, stk_linker): New functions.
	(Target_powerpc::Track_tls::maybe_skip_tls_get_addr_call): Add
	target param.  Update callers.  Compare symbols rather than names.
	(Target_powerpc::do_define_standard_symbols): Init tls_get_addr_
	and tls_get_addr_opt_.
	(Target_powerpc::Branch_info::mark_pltcall): Translate tls_get_addr
	sym to tls_get_addr_opt.
	(Target_powerpc::Branch_info::make_stub): Likewise.
	(Stub_table::define_stub_syms): Likewise.
	(Target_powerpc::Scan::global): Likewise.
	(Target_powerpc::Relocate::relocate): Likewise.
	(add_3_12_2, add_3_12_13, bctrl, beqlr, cmpdi_11_0, cmpwi_11_0,
	ld_11_1, ld_11_3, ld_12_3, lwz_11_3, lwz_12_3, mr_0_3, mr_3_0,
	mtlr_11, std_11_1): New constants.
	(Stub_table::eh_frame_added_): Delete.
	(Stub_table::tls_get_addr_opt_bctrl_, plt_fde_len_, plt_fde_): New vars.
	(Stub_table::init_plt_fde): New functions.
	(Stub_table::add_eh_frame, replace_eh_frame): Move definition out
	of line.  Init and use plt_fde_.
	(Stub_table::plt_call_size): Return size for tls_get_addr stub.
	Extract alignment code to..
	(Stub_table::plt_call_align): ..this new function.  Adjust all callers.
	(Stub_table::add_plt_call_entry): Set has_tls_get_addr_opt and
	tls_get_addr_opt_bctrl, and align after that.
	(Stub_table::do_write): Write out tls_get_addr stub.
	(Target_powerpc::do_finalize_sections): Emit DT_PPC_OPT
	PPC_OPT_TLS/PPC64_OPT_TLS bit.
	(Target_powerpc::Relocate::relocate): Don't check for or modify
	nop following bl for tls_get_addr stub.
2017-08-29 21:29:37 +09:30

291 lines
8.4 KiB
C++

// powerpc.h -- ELF definitions specific to EM_PPC and EM_PPC64 -*- C++ -*-
// Copyright (C) 2008-2017 Free Software Foundation, Inc.
// Written by David S. Miller <davem@davemloft.net>.
// This file is part of elfcpp.
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public License
// as published by the Free Software Foundation; either version 2, or
// (at your option) any later version.
// In addition to the permissions in the GNU Library General Public
// License, the Free Software Foundation gives you unlimited
// permission to link the compiled version of this file into
// combinations with other programs, and to distribute those
// combinations without any restriction coming from the use of this
// file. (The Library Public License restrictions do apply in other
// respects; for example, they cover modification of the file, and
/// distribution when not linked into a combined executable.)
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
// You should have received a copy of the GNU Library General Public
// License along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
// 02110-1301, USA.
#ifndef ELFCPP_POWERPC_H
#define ELFCPP_POWERPC_H
namespace elfcpp
{
// The relocation numbers for 32-bit and 64-bit powerpc are nearly
// identical. Therefore I've adopted the convention of using
// R_POWERPC_foo for values which are the same in R_PPC_* and R_PPC64_*.
// For relocations which are specific to the word size I will use
// R_PPC_foo or R_PPC64_foo.
enum
{
R_POWERPC_NONE = 0,
R_POWERPC_ADDR32 = 1,
R_POWERPC_ADDR24 = 2,
R_POWERPC_ADDR16 = 3,
R_POWERPC_ADDR16_LO = 4,
R_POWERPC_ADDR16_HI = 5,
R_POWERPC_ADDR16_HA = 6,
R_POWERPC_ADDR14 = 7,
R_POWERPC_ADDR14_BRTAKEN = 8,
R_POWERPC_ADDR14_BRNTAKEN = 9,
R_POWERPC_REL24 = 10,
R_POWERPC_REL14 = 11,
R_POWERPC_REL14_BRTAKEN = 12,
R_POWERPC_REL14_BRNTAKEN = 13,
R_POWERPC_GOT16 = 14,
R_POWERPC_GOT16_LO = 15,
R_POWERPC_GOT16_HI = 16,
R_POWERPC_GOT16_HA = 17,
R_PPC_PLTREL24 = 18,
R_POWERPC_COPY = 19,
R_POWERPC_GLOB_DAT = 20,
R_POWERPC_JMP_SLOT = 21,
R_POWERPC_RELATIVE = 22,
R_PPC_LOCAL24PC = 23,
R_POWERPC_UADDR32 = 24,
R_POWERPC_UADDR16 = 25,
R_POWERPC_REL32 = 26,
R_POWERPC_PLT32 = 27,
R_POWERPC_PLTREL32 = 28,
R_POWERPC_PLT16_LO = 29,
R_POWERPC_PLT16_HI = 30,
R_POWERPC_PLT16_HA = 31,
R_PPC_SDAREL16 = 32,
R_POWERPC_SECTOFF = 33,
R_POWERPC_SECTOFF_LO = 34,
R_POWERPC_SECTOFF_HI = 35,
R_POWERPC_SECTOFF_HA = 36,
R_POWERPC_ADDR30 = 37,
R_PPC64_ADDR64 = 38,
R_PPC64_ADDR16_HIGHER = 39,
R_PPC64_ADDR16_HIGHERA = 40,
R_PPC64_ADDR16_HIGHEST = 41,
R_PPC64_ADDR16_HIGHESTA = 42,
R_PPC64_UADDR64 = 43,
R_PPC64_REL64 = 44,
R_PPC64_PLT64 = 45,
R_PPC64_PLTREL64 = 46,
R_PPC64_TOC16 = 47,
R_PPC64_TOC16_LO = 48,
R_PPC64_TOC16_HI = 49,
R_PPC64_TOC16_HA = 50,
R_PPC64_TOC = 51,
R_PPC64_PLTGOT16 = 52,
R_PPC64_PLTGOT16_LO = 53,
R_PPC64_PLTGOT16_HI = 54,
R_PPC64_PLTGOT16_HA = 55,
R_PPC64_ADDR16_DS = 56,
R_PPC64_ADDR16_LO_DS = 57,
R_PPC64_GOT16_DS = 58,
R_PPC64_GOT16_LO_DS = 59,
R_PPC64_PLT16_LO_DS = 60,
R_PPC64_SECTOFF_DS = 61,
R_PPC64_SECTOFF_LO_DS = 62,
R_PPC64_TOC16_DS = 63,
R_PPC64_TOC16_LO_DS = 64,
R_PPC64_PLTGOT16_DS = 65,
R_PPC64_PLTGOT16_LO_DS = 66,
R_POWERPC_TLS = 67,
R_POWERPC_DTPMOD = 68,
R_POWERPC_TPREL16 = 69,
R_POWERPC_TPREL16_LO = 70,
R_POWERPC_TPREL16_HI = 71,
R_POWERPC_TPREL16_HA = 72,
R_POWERPC_TPREL = 73,
R_POWERPC_DTPREL16 = 74,
R_POWERPC_DTPREL16_LO = 75,
R_POWERPC_DTPREL16_HI = 76,
R_POWERPC_DTPREL16_HA = 77,
R_POWERPC_DTPREL = 78,
R_POWERPC_GOT_TLSGD16 = 79,
R_POWERPC_GOT_TLSGD16_LO = 80,
R_POWERPC_GOT_TLSGD16_HI = 81,
R_POWERPC_GOT_TLSGD16_HA = 82,
R_POWERPC_GOT_TLSLD16 = 83,
R_POWERPC_GOT_TLSLD16_LO = 84,
R_POWERPC_GOT_TLSLD16_HI = 85,
R_POWERPC_GOT_TLSLD16_HA = 86,
R_POWERPC_GOT_TPREL16 = 87,
R_POWERPC_GOT_TPREL16_LO = 88,
R_POWERPC_GOT_TPREL16_HI = 89,
R_POWERPC_GOT_TPREL16_HA = 90,
R_POWERPC_GOT_DTPREL16 = 91,
R_POWERPC_GOT_DTPREL16_LO = 92,
R_POWERPC_GOT_DTPREL16_HI = 93,
R_POWERPC_GOT_DTPREL16_HA = 94,
R_PPC_TLSGD = 95,
R_PPC64_TPREL16_DS = 95,
R_PPC_TLSLD = 96,
R_PPC64_TPREL16_LO_DS = 96,
R_PPC64_TPREL16_HIGHER = 97,
R_PPC64_TPREL16_HIGHERA = 98,
R_PPC64_TPREL16_HIGHEST = 99,
R_PPC64_TPREL16_HIGHESTA = 100,
R_PPC_EMB_NADDR32 = 101,
R_PPC64_DTPREL16_DS = 101,
R_PPC_EMB_NADDR16 = 102,
R_PPC64_DTPREL16_LO_DS = 102,
R_PPC_EMB_NADDR16_LO = 103,
R_PPC64_DTPREL16_HIGHER = 103,
R_PPC_EMB_NADDR16_HI = 104,
R_PPC64_DTPREL16_HIGHERA = 104,
R_PPC_EMB_NADDR16_HA = 105,
R_PPC64_DTPREL16_HIGHEST = 105,
R_PPC_EMB_SDAI16 = 106,
R_PPC64_DTPREL16_HIGHESTA = 106,
R_PPC_EMB_SDA2I16 = 107,
R_PPC64_TLSGD = 107,
R_PPC_EMB_SDA2REL = 108,
R_PPC64_TLSLD = 108,
R_PPC_EMB_SDA21 = 109,
R_PPC64_TOCSAVE = 109,
R_PPC_EMB_MRKREF = 110,
R_PPC64_ADDR16_HIGH = 110,
R_PPC_EMB_RELSEC16 = 111,
R_PPC64_ADDR16_HIGHA = 111,
R_PPC_EMB_RELST_LO = 112,
R_PPC64_TPREL16_HIGH = 112,
R_PPC_EMB_RELST_HI = 113,
R_PPC64_TPREL16_HIGHA = 113,
R_PPC_EMB_RELST_HA = 114,
R_PPC64_DTPREL16_HIGH = 114,
R_PPC_EMB_BIT_FLD = 115,
R_PPC64_DTPREL16_HIGHA = 115,
R_PPC_EMB_RELSDA = 116,
R_PPC64_REL24_NOTOC = 116,
R_PPC64_ADDR64_LOCAL = 117,
R_PPC64_ENTRY = 118,
R_PPC_VLE_REL8 = 216,
R_PPC_VLE_REL15 = 217,
R_PPC_VLE_REL24 = 218,
R_PPC_VLE_LO16A = 219,
R_PPC_VLE_LO16D = 220,
R_PPC_VLE_HI16A = 221,
R_PPC_VLE_HI16D = 222,
R_PPC_VLE_HA16A = 223,
R_PPC_VLE_HA16D = 224,
R_PPC_VLE_SDA21 = 225,
R_PPC_VLE_SDA21_LO = 226,
R_PPC_VLE_SDAREL_LO16A = 227,
R_PPC_VLE_SDAREL_LO16D = 228,
R_PPC_VLE_SDAREL_HI16A = 229,
R_PPC_VLE_SDAREL_HI16D = 230,
R_PPC_VLE_SDAREL_HA16A = 231,
R_PPC_VLE_SDAREL_HA16D = 232,
R_POWERPC_REL16DX_HA = 246,
R_PPC64_JMP_IREL = 247,
R_POWERPC_IRELATIVE = 248,
R_POWERPC_REL16 = 249,
R_POWERPC_REL16_LO = 250,
R_POWERPC_REL16_HI = 251,
R_POWERPC_REL16_HA = 252,
R_POWERPC_GNU_VTINHERIT = 253,
R_POWERPC_GNU_VTENTRY = 254,
R_PPC_TOC16 = 255,
};
// e_flags values defined for powerpc
enum
{
EF_PPC_EMB = 0x80000000, // PowerPC embedded flag.
EF_PPC_RELOCATABLE = 0x00010000, // PowerPC -mrelocatable flag. */
EF_PPC_RELOCATABLE_LIB = 0x00008000, // PowerPC -mrelocatable-lib flag. */
};
// e_flags values defined for powerpc64
enum
{
// ABI version
// 1 for original function descriptor using ABI,
// 2 for revised ABI without function descriptors,
// 0 for unspecified or not using any features affected by the differences.
EF_PPC64_ABI = 3
};
// DT_PPC_OPT bits
enum
{
PPC_OPT_TLS = 1
};
// DT_PPC64_OPT bits
enum
{
PPC64_OPT_TLS = 1,
PPC64_OPT_MULTI_TOC = 2,
PPC64_OPT_LOCALENTRY = 4
};
enum
{
// The ELFv2 ABI uses three bits in the symbol st_other field of a
// function definition to specify the number of instructions between a
// function's global entry point and local entry point.
// The global entry point is used when it is necessary to set up the
// toc pointer (r2) for the function. Callers must enter the global
// entry point with r12 set to the global entry point address. On
// return from the function, r2 may have a different value to that
// which it had on entry.
// The local entry point is used when r2 is known to already be valid
// for the function. There is no requirement on r12 when using the
// local entry point, and on return r2 will contain the same value as
// at entry.
// A value of zero in these bits means that the function has a single
// entry point with no requirement on r12 or r2, and that on return r2
// will contain the same value as at entry.
// Values of one and seven are reserved.
STO_PPC64_LOCAL_BIT = 5,
STO_PPC64_LOCAL_MASK = 0xE0
};
// 3 bit other field to bytes.
static inline unsigned int
ppc64_decode_local_entry(unsigned int other)
{
return ((1 << other) >> 2) << 2;
}
// bytes to field value.
static inline unsigned int
ppc64_encode_local_entry(unsigned int val)
{
return (val >= 4 * 4
? (val >= 8 * 4
? (val >= 16 * 4 ? 6 : 5)
: 4)
: (val >= 2 * 4
? 3
: (val >= 1 * 4 ? 2 : 0)));
}
} // End namespace elfcpp.
#endif // !defined(ELFCPP_POWERPC_H)