binutils-gdb/include/elf/riscv.h
Nelson Chu 8155b8539b RISC-V: Support STO_RISCV_VARIANT_CC and DT_RISCV_VARIANT_CC.
This is the original discussion,
https://github.com/riscv/riscv-elf-psabi-doc/pull/190

And here is the glibc part,
https://sourceware.org/pipermail/libc-alpha/2021-August/129931.html

For binutils part, we need to support a new direcitve: .variant_cc.
The function symbol marked by .variant_cc means it need to be resolved
directly without resolver for dynamic linker.  We also add a new dynamic
entry, STO_RISCV_VARIANT_CC, to indicate there are symbols with the
special attribute in the dynamic symbol table of the object.

I heard that llvm already have supported this in their mainline, so
I think it's time to commit this.

bfd/
	* elfnn-riscv.c (riscv_elf_link_hash_table): Added variant_cc
	flag. It is used to check if relocations for variant CC symbols
	may be present.
	(allocate_dynrelocs): If the symbol has STO_RISCV_VARIANT_CC
	flag, then raise the variant_cc flag of riscv_elf_link_hash_table.
	(riscv_elf_size_dynamic_sections): Added dynamic entry for
	variant_cc.
	(riscv_elf_merge_symbol_attribute): New function, used to merge
	non-visibility st_other attributes, including STO_RISCV_VARIANT_CC.
binutils/
	* readelf.c (get_riscv_dynamic_type): New function.
	(get_dynamic_type): Called get_riscv_dynamic_type for riscv targets.
	(get_riscv_symbol_other): New function.
	(get_symbol_other): Called get_riscv_symbol_other for riscv targets.
gas/
	* config/tc-riscv.c (s_variant_cc): Marked symbol that it follows a
	variant CC convention.
	(riscv_elf_copy_symbol_attributes): Same as elf_copy_symbol_attributes,
	but without copying st_other.  If a function symbol has special st_other
	value set via directives, then attaching an IFUNC resolver to that symbol
	should not override the st_other setting.
	(riscv_pseudo_table): Support variant_cc diretive.
	* config/tc-riscv.h (OBJ_COPY_SYMBOL_ATTRIBUTES): Defined.
	* testsuite/gas/riscv/variant_cc-set.d: New testcase.
	* testsuite/gas/riscv/variant_cc-set.s: Likewise.
	* testsuite/gas/riscv/variant_cc.d: Likewise.
	* testsuite/gas/riscv/variant_cc.s: Likewise.
include/
	* elf/riscv.h (DT_RISCV_VARIANT_CC): Defined to (DT_LOPROC + 1).
	(STO_RISCV_VARIANT_CC): Defined to 0x80.
ld/
	* testsuite/ld-riscv-elf/variant_cc-1.s: New testcase.
	* testsuite/ld-riscv-elf/variant_cc-2.s: Likewise.
	* testsuite/ld-riscv-elf/variant_cc-now.d: Likewise.
	* testsuite/ld-riscv-elf/variant_cc-r.d: Likewise.
	* testsuite/ld-riscv-elf/variant_cc-shared.d: Likewise.
	* testsuite/ld-riscv-elf/ld-riscv-elf.exp: Updated.
2021-11-19 09:32:19 +08:00

147 lines
4.7 KiB
C

/* RISC-V ELF support for BFD.
Copyright (C) 2011-2021 Free Software Foundation, Inc.
Contributed by Andrew Waterman (andrew@sifive.com).
Based on MIPS ELF support for BFD, by Ian Lance Taylor.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING3. If not,
see <http://www.gnu.org/licenses/>. */
/* This file holds definitions specific to the RISCV ELF ABI. Note
that most of this is not actually implemented by BFD. */
#ifndef _ELF_RISCV_H
#define _ELF_RISCV_H
#include "elf/reloc-macros.h"
#include "libiberty.h"
/* Relocation types. */
START_RELOC_NUMBERS (elf_riscv_reloc_type)
/* Relocation types used by the dynamic linker. */
RELOC_NUMBER (R_RISCV_NONE, 0)
RELOC_NUMBER (R_RISCV_32, 1)
RELOC_NUMBER (R_RISCV_64, 2)
RELOC_NUMBER (R_RISCV_RELATIVE, 3)
RELOC_NUMBER (R_RISCV_COPY, 4)
RELOC_NUMBER (R_RISCV_JUMP_SLOT, 5)
RELOC_NUMBER (R_RISCV_TLS_DTPMOD32, 6)
RELOC_NUMBER (R_RISCV_TLS_DTPMOD64, 7)
RELOC_NUMBER (R_RISCV_TLS_DTPREL32, 8)
RELOC_NUMBER (R_RISCV_TLS_DTPREL64, 9)
RELOC_NUMBER (R_RISCV_TLS_TPREL32, 10)
RELOC_NUMBER (R_RISCV_TLS_TPREL64, 11)
/* Relocation types not used by the dynamic linker. */
RELOC_NUMBER (R_RISCV_BRANCH, 16)
RELOC_NUMBER (R_RISCV_JAL, 17)
RELOC_NUMBER (R_RISCV_CALL, 18)
RELOC_NUMBER (R_RISCV_CALL_PLT, 19)
RELOC_NUMBER (R_RISCV_GOT_HI20, 20)
RELOC_NUMBER (R_RISCV_TLS_GOT_HI20, 21)
RELOC_NUMBER (R_RISCV_TLS_GD_HI20, 22)
RELOC_NUMBER (R_RISCV_PCREL_HI20, 23)
RELOC_NUMBER (R_RISCV_PCREL_LO12_I, 24)
RELOC_NUMBER (R_RISCV_PCREL_LO12_S, 25)
RELOC_NUMBER (R_RISCV_HI20, 26)
RELOC_NUMBER (R_RISCV_LO12_I, 27)
RELOC_NUMBER (R_RISCV_LO12_S, 28)
RELOC_NUMBER (R_RISCV_TPREL_HI20, 29)
RELOC_NUMBER (R_RISCV_TPREL_LO12_I, 30)
RELOC_NUMBER (R_RISCV_TPREL_LO12_S, 31)
RELOC_NUMBER (R_RISCV_TPREL_ADD, 32)
RELOC_NUMBER (R_RISCV_ADD8, 33)
RELOC_NUMBER (R_RISCV_ADD16, 34)
RELOC_NUMBER (R_RISCV_ADD32, 35)
RELOC_NUMBER (R_RISCV_ADD64, 36)
RELOC_NUMBER (R_RISCV_SUB8, 37)
RELOC_NUMBER (R_RISCV_SUB16, 38)
RELOC_NUMBER (R_RISCV_SUB32, 39)
RELOC_NUMBER (R_RISCV_SUB64, 40)
RELOC_NUMBER (R_RISCV_GNU_VTINHERIT, 41)
RELOC_NUMBER (R_RISCV_GNU_VTENTRY, 42)
RELOC_NUMBER (R_RISCV_ALIGN, 43)
RELOC_NUMBER (R_RISCV_RVC_BRANCH, 44)
RELOC_NUMBER (R_RISCV_RVC_JUMP, 45)
RELOC_NUMBER (R_RISCV_RVC_LUI, 46)
RELOC_NUMBER (R_RISCV_GPREL_I, 47)
RELOC_NUMBER (R_RISCV_GPREL_S, 48)
RELOC_NUMBER (R_RISCV_TPREL_I, 49)
RELOC_NUMBER (R_RISCV_TPREL_S, 50)
RELOC_NUMBER (R_RISCV_RELAX, 51)
RELOC_NUMBER (R_RISCV_SUB6, 52)
RELOC_NUMBER (R_RISCV_SET6, 53)
RELOC_NUMBER (R_RISCV_SET8, 54)
RELOC_NUMBER (R_RISCV_SET16, 55)
RELOC_NUMBER (R_RISCV_SET32, 56)
RELOC_NUMBER (R_RISCV_32_PCREL, 57)
RELOC_NUMBER (R_RISCV_IRELATIVE, 58)
END_RELOC_NUMBERS (R_RISCV_max)
/* Processor specific flags for the ELF header e_flags field. */
/* File may contain compressed instructions. */
#define EF_RISCV_RVC 0x0001
/* Which floating-point ABI a file uses. */
#define EF_RISCV_FLOAT_ABI 0x0006
/* File uses the soft-float ABI. */
#define EF_RISCV_FLOAT_ABI_SOFT 0x0000
/* File uses the single-float ABI. */
#define EF_RISCV_FLOAT_ABI_SINGLE 0x0002
/* File uses the double-float ABI. */
#define EF_RISCV_FLOAT_ABI_DOUBLE 0x0004
/* File uses the quad-float ABI. */
#define EF_RISCV_FLOAT_ABI_QUAD 0x0006
/* File uses the 32E base integer instruction. */
#define EF_RISCV_RVE 0x0008
/* The name of the global pointer symbol. */
#define RISCV_GP_SYMBOL "__global_pointer$"
/* Processor specific dynamic array tags. */
#define DT_RISCV_VARIANT_CC (DT_LOPROC + 1)
/* RISC-V specific values for st_other. */
#define STO_RISCV_VARIANT_CC 0x80
/* Additional section types. */
#define SHT_RISCV_ATTRIBUTES 0x70000003 /* Section holds attributes. */
/* Processor specific program header types. */
/* Location of RISC-V ELF attribute section. */
#define PT_RISCV_ATTRIBUTES 0x70000003
/* Object attributes. */
enum
{
/* 0-3 are generic. */
Tag_RISCV_stack_align = 4,
Tag_RISCV_arch = 5,
Tag_RISCV_unaligned_access = 6,
Tag_RISCV_priv_spec = 8,
Tag_RISCV_priv_spec_minor = 10,
Tag_RISCV_priv_spec_revision = 12
};
#endif /* _ELF_RISCV_H */