binutils-gdb/gas/config/tc-riscv.h
Nelson Chu 9b9b1092f0 RISC-V: PR27916, Support mapping symbols.
Similar to ARM/AARCH64, we add mapping symbols in the symbol table,
to mark the start addresses of data and instructions.  The $d means
data, and the $x means instruction.  Then the disassembler uses these
symbols to decide whether we should dump data or instruction.

Consider the mapping-04 test case,
$ cat tmp.s
  .text
  .option norelax
  .option norvc
  .fill 2, 4, 0x1001
  .byte 1
  .word 0
  .balign 8
  add a0, a0, a0
  .fill 5, 2, 0x2002
  add a1, a1, a1
  .data
  .word 0x1             # No need to add mapping symbols.
  .word 0x2

$ riscv64-unknown-elf-as tmp.s -o tmp.o
$ riscv64-unknown-elf-objdump -d tmp.o

Disassembly of section .text:

0000000000000000 <.text>:
   0:   00001001         .word   0x00001001  # Marked $d, .fill directive.
   4:   00001001         .word   0x00001001
   8:   00000001         .word   0x00000001  # .byte + part of .word.
   c:   00               .byte   0x00        # remaining .word.
   d:   00               .byte   0x00        # Marked $d, odd byte of alignment.
   e:   0001             nop                 # Marked $x, nops for alignment.
  10:   00a50533         add     a0,a0,a0
  14:   20022002         .word   0x20022002  # Marked $d, .fill directive.
  18:   20022002         .word   0x20022002
  1c:   2002             .short  0x2002
  1e:   00b585b3         add     a1,a1,a1    # Marked $x.
  22:   0001             nop                 # Section tail alignment.
  24:   00000013         nop

* Use $d and $x to mark the distribution of data and instructions.
  Alignments of code are recognized as instructions, since we usually
  fill nops for them.

* If the alignment have odd bytes, then we cannot just fill the nops
  into the spaces.  We always fill an odd byte 0x00 at the start of
  the spaces.  Therefore, add a $d mapping symbol for the odd byte,
  to tell disassembler that it isn't an instruction.  The behavior
  is same as Arm and Aarch64.

The elf/linux toolchain regressions all passed.  Besides, I also
disable the mapping symbols internally, but use the new objudmp, the
regressions passed, too.  Therefore, the new objudmp should dump
the objects corretly, even if they don't have any mapping symbols.

bfd/
	pr 27916
	* cpu-riscv.c (riscv_elf_is_mapping_symbols): Define mapping symbols.
	* cpu-riscv.h: extern riscv_elf_is_mapping_symbols.
	* elfnn-riscv.c (riscv_maybe_function_sym): Do not choose mapping
	symbols as a function name.
	(riscv_elf_is_target_special_symbol): Add mapping symbols.
binutils/
	pr 27916
	* testsuite/binutils-all/readelf.s: Updated.
	* testsuite/binutils-all/readelf.s-64: Likewise.
	* testsuite/binutils-all/readelf.s-64-unused: Likewise.
	* testsuite/binutils-all/readelf.ss: Likewise.
	* testsuite/binutils-all/readelf.ss-64: Likewise.
	* testsuite/binutils-all/readelf.ss-64-unused: Likewise.
gas/
	pr 27916
	* config/tc-riscv.c (make_mapping_symbol): Create a new mapping symbol.
	(riscv_mapping_state): Decide whether to create mapping symbol for
	frag_now.  Only add the mapping symbols to text sections.
	(riscv_add_odd_padding_symbol): Add the mapping symbols for the
	riscv_handle_align, which have odd bytes spaces.
	(riscv_check_mapping_symbols): Remove any excess mapping symbols.
	(md_assemble): Marked as MAP_INSN.
	(riscv_frag_align_code): Marked as MAP_INSN.
	(riscv_init_frag): Add mapping symbols for frag, it usually called
	by frag_var.  Marked as MAP_DATA for rs_align and rs_fill, and
	marked as MAP_INSN for rs_align_code.
	(s_riscv_insn): Marked as MAP_INSN.
	(riscv_adjust_symtab): Call riscv_check_mapping_symbols.
	* config/tc-riscv.h (md_cons_align): Defined to riscv_mapping_state
	with MAP_DATA.
	(TC_SEGMENT_INFO_TYPE): Record mapping state for each segment.
	(TC_FRAG_TYPE): Record the first and last mapping symbols for the
	fragments.  The first mapping symbol must be placed at the start
	of the fragment.
	(TC_FRAG_INIT): Defined to riscv_init_frag.
	* testsuite/gas/riscv/mapping-01.s: New testcase.
	* testsuite/gas/riscv/mapping-01a.d: Likewise.
	* testsuite/gas/riscv/mapping-01b.d: Likewise.
	* testsuite/gas/riscv/mapping-02.s: Likewise.
	* testsuite/gas/riscv/mapping-02a.d: Likewise.
	* testsuite/gas/riscv/mapping-02b.d: Likewise.
	* testsuite/gas/riscv/mapping-03.s: Likewise.
	* testsuite/gas/riscv/mapping-03a.d: Likewise.
	* testsuite/gas/riscv/mapping-03b.d: Likewise.
	* testsuite/gas/riscv/mapping-04.s: Likewise.
	* testsuite/gas/riscv/mapping-04a.d: Likewise.
	* testsuite/gas/riscv/mapping-04b.d: Likewise.
	* testsuite/gas/riscv/mapping-norelax-04a.d: Likewise.
	* testsuite/gas/riscv/mapping-norelax-04b.d: Likewise.
	* testsuite/gas/riscv/no-relax-align.d: Updated.
	* testsuite/gas/riscv/no-relax-align-2.d: Likewise.
include/
	pr 27916
	* opcode/riscv.h (enum riscv_seg_mstate): Added.

opcodes/
	pr 27916
	* riscv-dis.c (last_map_symbol, last_stop_offset, last_map_state):
	Added to dump sections with mapping symbols.
	(riscv_get_map_state): Get the mapping state from the symbol.
	(riscv_search_mapping_symbol): Check the sorted symbol table, and
	then find the suitable mapping symbol.
	(riscv_data_length): Decide which data size we should print.
	(riscv_disassemble_data): Dump the data contents.
	(print_insn_riscv): Handle the mapping symbols.
	(riscv_symbol_is_valid): Marked mapping symbols as invalid.
2021-08-30 17:36:11 +08:00

156 lines
5.0 KiB
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);
#endif /* TC_RISCV */