binutils-gdb/gas/config/tc-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

160 lines
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C

/* tc-riscv.h -- header file for tc-riscv.c.
Copyright (C) 2011-2021 Free Software Foundation, Inc.
Contributed by Andrew Waterman (andrew@sifive.com).
Based on MIPS target.
This file is part of GAS.
GAS 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, or (at your option)
any later version.
GAS 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/>. */
#ifndef TC_RISCV
#define TC_RISCV
#include "opcode/riscv.h"
struct frag;
struct expressionS;
#ifndef TARGET_BYTES_BIG_ENDIAN
#define TARGET_BYTES_BIG_ENDIAN 0
#endif
#define TARGET_ARCH bfd_arch_riscv
#define WORKING_DOT_WORD 1
#define LOCAL_LABELS_FB 1
/* Symbols named FAKE_LABEL_NAME are emitted when generating DWARF, so make
sure FAKE_LABEL_NAME is printable. It still must be distinct from any
real label name. So, append a space, which other labels can't contain. */
#define FAKE_LABEL_NAME RISCV_FAKE_LABEL_NAME
/* Changing the special character in FAKE_LABEL_NAME requires changing
FAKE_LABEL_CHAR too. */
#define FAKE_LABEL_CHAR RISCV_FAKE_LABEL_CHAR
#define md_relax_frag(segment, fragp, stretch) \
riscv_relax_frag (segment, fragp, stretch)
extern int riscv_relax_frag (asection *, struct frag *, long);
#define md_section_align(seg,size) (size)
#define md_undefined_symbol(name) (0)
#define md_operand(x)
extern bool riscv_frag_align_code (int);
#define md_do_align(N, FILL, LEN, MAX, LABEL) \
if ((N) != 0 && !(FILL) && !need_pass_2 && subseg_text_p (now_seg)) \
{ \
if (riscv_frag_align_code (N)) \
goto LABEL; \
}
extern void riscv_handle_align (fragS *);
#define HANDLE_ALIGN riscv_handle_align
#define MAX_MEM_FOR_RS_ALIGN_CODE (3 + 4)
/* The ISA of the target may change based on command-line arguments. */
#define TARGET_FORMAT riscv_target_format ()
extern const char * riscv_target_format (void);
#define md_after_parse_args() riscv_after_parse_args ()
extern void riscv_after_parse_args (void);
#define md_parse_long_option(arg) riscv_parse_long_option (arg)
extern int riscv_parse_long_option (const char *);
#define md_pre_output_hook riscv_pre_output_hook ()
extern void riscv_pre_output_hook (void);
/* Let the linker resolve all the relocs due to relaxation. */
#define tc_fix_adjustable(fixp) 0
#define md_allow_local_subtract(l,r,s) 0
/* Values passed to md_apply_fix don't include symbol values. */
#define MD_APPLY_SYM_VALUE(FIX) 0
/* Global syms must not be resolved, to support ELF shared libraries. */
#define EXTERN_FORCE_RELOC \
(OUTPUT_FLAVOR == bfd_target_elf_flavour)
/* Postpone text-section label subtraction calculation until linking, since
linker relaxations might change the deltas. */
#define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
(GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEG) \
|| ((SEG)->flags & SEC_CODE) != 0)
#define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) 1
#define TC_VALIDATE_FIX_SUB(FIX, SEG) 1
#define TC_FORCE_RELOCATION_LOCAL(FIX) 1
#define DIFF_EXPR_OK 1
extern void riscv_pop_insert (void);
#define md_pop_insert() riscv_pop_insert ()
#define TARGET_USE_CFIPOP 1
#define tc_cfi_frame_initial_instructions riscv_cfi_frame_initial_instructions
extern void riscv_cfi_frame_initial_instructions (void);
#define tc_regname_to_dw2regnum tc_riscv_regname_to_dw2regnum
extern int tc_riscv_regname_to_dw2regnum (char *);
#define DWARF2_DEFAULT_RETURN_COLUMN X_RA
/* Even on RV64, use 4-byte alignment, as F registers may be only 32 bits. */
#define DWARF2_CIE_DATA_ALIGNMENT -4
#define elf_tc_final_processing riscv_elf_final_processing
extern void riscv_elf_final_processing (void);
/* Adjust debug_line after relaxation. */
#define DWARF2_USE_FIXED_ADVANCE_PC 1
#define md_end riscv_md_end
#define CONVERT_SYMBOLIC_ATTRIBUTE riscv_convert_symbolic_attribute
extern void riscv_md_end (void);
extern int riscv_convert_symbolic_attribute (const char *);
/* Set mapping symbol states. */
#define md_cons_align(nbytes) riscv_mapping_state (MAP_DATA, 0)
void riscv_mapping_state (enum riscv_seg_mstate, int);
/* Define target segment type. */
#define TC_SEGMENT_INFO_TYPE struct riscv_segment_info_type
struct riscv_segment_info_type
{
enum riscv_seg_mstate map_state;
};
/* Define target fragment type. */
#define TC_FRAG_TYPE struct riscv_frag_type
struct riscv_frag_type
{
symbolS *first_map_symbol, *last_map_symbol;
};
#define TC_FRAG_INIT(fragp, max_bytes) riscv_init_frag (fragp, max_bytes)
extern void riscv_init_frag (struct frag *, int);
#define obj_adjust_symtab() riscv_adjust_symtab ()
extern void riscv_adjust_symtab (void);
void riscv_elf_copy_symbol_attributes (symbolS *, symbolS *);
#define OBJ_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
riscv_elf_copy_symbol_attributes (DEST, SRC)
#endif /* TC_RISCV */