Re: [PATCH v1] LoongArch: Use less DW_LNS_fixed_advance_pc
mengqinggang <[email protected]>
| Newsgroups | gmane.comp.gnu.binutils |
|---|---|
| Message-ID | <[email protected]> |
Hi Alan,
Thanks! Just to confirm, can this patch be merged?
在 2026/8/26 21:05, Alan Modra 写道:
> On Wed, Aug 26, 2026 at 02:38:53PM +0800, mengqinggang wrote:
>> Gentle ping.
> OK.
>
>> 在 2026/8/19 11:41, mengqinggang 写道:
>>> If DWARF2_USE_FIXED_ADVANCE_PC is nonzero, use the DW_LNS_fixed_advance_pc
>>> opcode; otherwise, use special opcodes.
>>>
>>> Add FROM symbol and TO symbol parameters for finer-grained control.
>>>
>>> Use special opcodes when no linker-relaxable instructions between two symbols;
>>> otherwise, use DW_LNS_fixed_advance_pc opcodes.
>>>
>>> Add a new macro DWARF2_USE_FIXED_ADVANCE_PC_FRAG to avoid unnecessary calls
>>> to symbol_get_value_expression on other targets.
>>> ---
>>> Changes in V1 (based on Alan's feedback):
>>> - Delete the first DWARF2_USE_FIXED_ADVANCE_PC and always call
>>> resolve_symbol_value with finalize_syms zero in dwarf2dbg_convert_frag.
>>> - Add a new macro DWARF2_USE_FIXED_ADVANCE_PC_FRAG to avoid unnecessary
>>> calls to symbol_get_value_expression on other targets.
>>>
>>> gas/config/tc-h8300.h | 2 +-
>>> gas/config/tc-loongarch.c | 25 ++++++++++
>>> gas/config/tc-loongarch.h | 10 +++-
>>> gas/config/tc-msp430.h | 2 +-
>>> gas/config/tc-nds32.h | 2 +-
>>> gas/config/tc-riscv.h | 2 +-
>>> gas/config/tc-rl78.h | 2 +-
>>> gas/config/tc-xtensa.h | 2 +-
>>> gas/dwarf2dbg.c | 49 ++++++++++---------
>>> gas/testsuite/gas/elf/dwarf-5-irp.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf-5-loc0.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf-5-macro-include.d | 2 +-
>>> gas/testsuite/gas/elf/dwarf-5-macro.d | 2 +-
>>> gas/testsuite/gas/elf/dwarf2-11.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf2-15.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf2-16.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf2-17.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf2-18.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf2-19.d | 3 +-
>>> gas/testsuite/gas/elf/dwarf2-5.d | 3 +-
>>> gas/testsuite/gas/lns/lns.exp | 1 -
>>> .../relax-debug-line-opcode-norelax.d | 10 ++++
>>> .../gas/loongarch/relax-debug-line-opcode.d | 25 ++++++++++
>>> .../gas/loongarch/relax-debug-line-opcode.s | 15 ++++++
>>> 24 files changed, 125 insertions(+), 53 deletions(-)
>>> create mode 100644 gas/testsuite/gas/loongarch/relax-debug-line-opcode-norelax.d
>>> create mode 100644 gas/testsuite/gas/loongarch/relax-debug-line-opcode.d
>>> create mode 100644 gas/testsuite/gas/loongarch/relax-debug-line-opcode.s
>>>
>>> diff --git a/gas/config/tc-h8300.h b/gas/config/tc-h8300.h
>>> index c4689d37b12..66664553a24 100644
>>> --- a/gas/config/tc-h8300.h
>>> +++ b/gas/config/tc-h8300.h
>>> @@ -46,7 +46,7 @@ struct internal_reloc;
>>> /* Minimum instruction is of 16 bits. */
>>> #define DWARF2_LINE_MIN_INSN_LENGTH 2
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC 0
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) 0
>>> /* Provide mappings from the original H8 COFF relocation names to
>>> their corresponding BFD relocation names. */
>>> diff --git a/gas/config/tc-loongarch.c b/gas/config/tc-loongarch.c
>>> index bd7d8dabb7a..e02881761fe 100644
>>> --- a/gas/config/tc-loongarch.c
>>> +++ b/gas/config/tc-loongarch.c
>>> @@ -1644,6 +1644,31 @@ _loongarch_force_relocation_sub_same (segT sec,
>>> return true;
>>> }
>>> +/* Use DW_LNS_fixed_advance_pc with relocations if there are linker-relaxable
>>> + instructions between from and to symbols. Otherwise, use special opcodes
>>> + without relocations. */
>>> +bool
>>> +loongarch_fixed_advance_pc (symbolS *from, symbolS *to)
>>> +{
>>> + segT fromsec = S_GET_SEGMENT (from);
>>> + segT tosec = S_GET_SEGMENT (to);
>>> + if (fromsec != tosec)
>>> + return false;
>>> + fragS *fromfrag = symbol_get_frag (from);
>>> + fragS *tofrag = symbol_get_frag (to);
>>> + return _loongarch_force_relocation_sub_same (fromsec, fromfrag, tofrag);
>>> +}
>>> +
>>> +/* Similar to loongarch_fixed_advance_pc, used for frag. */
>>> +bool
>>> +loongarch_fixed_advance_pc_frag (fragS *frag)
>>> +{
>>> + expressionS *exp = symbol_get_value_expression (frag->fr_symbol);
>>> +
>>> + if (exp->X_op != O_subtract)
>>> + return false;
>>> + return loongarch_fixed_advance_pc (exp->X_op_symbol, exp->X_add_symbol);
>>> +}
>>> /* Postpone text-section label subtraction calculation until linking,
>>> since linker relaxations might change the deltas. */
>>> diff --git a/gas/config/tc-loongarch.h b/gas/config/tc-loongarch.h
>>> index 146844e772e..1f11f9cef46 100644
>>> --- a/gas/config/tc-loongarch.h
>>> +++ b/gas/config/tc-loongarch.h
>>> @@ -101,8 +101,14 @@ extern bool loongarch_force_relocation_sub_same(struct fix *, asection *);
>>> #define MD_APPLY_SYM_VALUE(FIX) 0
>>> #define TARGET_USE_CFIPOP 1
>>> -/* Adjust debug_line after relaxation. */
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC 1
>>> +
>>> +extern bool loongarch_fixed_advance_pc (symbolS *, symbolS *);
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) \
>>> + loongarch_fixed_advance_pc (FROM, TO)
>>> +
>>> +extern bool loongarch_fixed_advance_pc_frag (fragS *);
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC_FRAG(FRAG) \
>>> + loongarch_fixed_advance_pc_frag (FRAG)
>>> /* FDE Data Alignment Factor.
>>> FDE Code Alignment Factor (DWARF2_LINE_MIN_INSN_LENGTH) should be 1
>>> diff --git a/gas/config/tc-msp430.h b/gas/config/tc-msp430.h
>>> index fe202abc713..f9b6c1e588c 100644
>>> --- a/gas/config/tc-msp430.h
>>> +++ b/gas/config/tc-msp430.h
>>> @@ -168,7 +168,7 @@ extern bool msp430_allow_local_subtract (expressionS *, expressionS *, segT);
>>> so don't report errors at this point. */
>>> #define TC_VALIDATE_FIX_SUB(FIX, SEG) 1
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC 1
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) 1
>>> #define TC_LINKRELAX_FIXUP(seg) ((seg->flags & SEC_CODE) || (seg->flags & SEC_DEBUGGING))
>>> diff --git a/gas/config/tc-nds32.h b/gas/config/tc-nds32.h
>>> index 432d46d9fb1..49a1bead095 100644
>>> --- a/gas/config/tc-nds32.h
>>> +++ b/gas/config/tc-nds32.h
>>> @@ -77,7 +77,7 @@ extern bool nds32_allow_local_subtract (expressionS *, expressionS *, segT);
>>> #define md_allow_local_subtract(lhs,rhs,sect) nds32_allow_local_subtract (lhs, rhs, sect)
>>> /* dwarf2dbg.c. */
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC 1
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) 1
>>> /* write.c. */
>>> extern long nds32_pcrel_from_section (struct fix *, segT);
>>> diff --git a/gas/config/tc-riscv.h b/gas/config/tc-riscv.h
>>> index d695db83477..7518d2a70f7 100644
>>> --- a/gas/config/tc-riscv.h
>>> +++ b/gas/config/tc-riscv.h
>>> @@ -135,7 +135,7 @@ extern void riscv_elf_section_change_hook (void);
>>> extern void riscv_elf_final_processing (void);
>>> /* Adjust debug_line after relaxation. */
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC 1
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) 1
>>> #define md_parse_name(name, exp, mode, c) \
>>> riscv_parse_name (name, exp, mode)
>>> diff --git a/gas/config/tc-rl78.h b/gas/config/tc-rl78.h
>>> index 9761d509aa1..fb54a2e8da7 100644
>>> --- a/gas/config/tc-rl78.h
>>> +++ b/gas/config/tc-rl78.h
>>> @@ -94,6 +94,6 @@ extern void rl78_elf_final_processing (void);
>>> || ((SEC)->flags & SEC_DEBUGGING) != 0 \
>>> || TC_FORCE_RELOCATION (FIX))
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC 1
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) 1
>>> #define TC_FORCE_RELOCATION(FIX) (linkrelax)
>>> diff --git a/gas/config/tc-xtensa.h b/gas/config/tc-xtensa.h
>>> index 64d735144d7..d6ddac738fe 100644
>>> --- a/gas/config/tc-xtensa.h
>>> +++ b/gas/config/tc-xtensa.h
>>> @@ -419,7 +419,7 @@ extern void xtensa_init (int, char **);
>>> #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
>>> /* Use line number format that is amenable to linker relaxation. */
>>> -#define DWARF2_USE_FIXED_ADVANCE_PC (linkrelax != 0)
>>> +#define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) (linkrelax != 0)
>>> /* Resource reservation info functions. */
>>> diff --git a/gas/dwarf2dbg.c b/gas/dwarf2dbg.c
>>> index a1ceab4e428..c899eecd26b 100644
>>> --- a/gas/dwarf2dbg.c
>>> +++ b/gas/dwarf2dbg.c
>>> @@ -112,7 +112,13 @@
>>> opcodes and variable-length operands cannot be used. If this macro is
>>> nonzero, use the DW_LNS_fixed_advance_pc opcode instead. */
>>> #ifndef DWARF2_USE_FIXED_ADVANCE_PC
>>> -# define DWARF2_USE_FIXED_ADVANCE_PC linkrelax
>>> +# define DWARF2_USE_FIXED_ADVANCE_PC(FROM, TO) linkrelax
>>> +#endif
>>> +
>>> +/* Similar to DWARF2_USE_FIXED_ADVANCE_PC, used for frag. */
>>> +#ifndef DWARF2_USE_FIXED_ADVANCE_PC_FRAG
>>> +# define DWARF2_USE_FIXED_ADVANCE_PC_FRAG(FRAG) \
>>> + DWARF2_USE_FIXED_ADVANCE_PC (0, 0)
>>> #endif
>>> /* First special line opcode - leave room for the standard opcodes.
>>> @@ -1898,7 +1904,7 @@ relax_inc_line_addr (int line_delta, symbolS *to_sym, symbolS *from_sym)
>>> /* The maximum size of the frag is the line delta with a maximum
>>> sized address delta. */
>>> - if (DWARF2_USE_FIXED_ADVANCE_PC)
>>> + if (DWARF2_USE_FIXED_ADVANCE_PC (from_sym, to_sym))
>>> max_chars = size_fixed_inc_line_addr (line_delta,
>>> -DWARF2_LINE_MIN_INSN_LENGTH);
>>> else
>>> @@ -1919,7 +1925,7 @@ dwarf2dbg_estimate_size_before_relax (fragS *frag)
>>> int size;
>>> addr_delta = resolve_symbol_value (frag->fr_symbol);
>>> - if (DWARF2_USE_FIXED_ADVANCE_PC)
>>> + if (DWARF2_USE_FIXED_ADVANCE_PC_FRAG (frag))
>>> size = size_fixed_inc_line_addr (frag->fr_offset, addr_delta);
>>> else
>>> size = size_inc_line_addr (frag->fr_offset, addr_delta);
>>> @@ -1953,31 +1959,25 @@ dwarf2dbg_convert_frag (fragS *frag)
>>> {
>>> offsetT addr_diff;
>>> - if (DWARF2_USE_FIXED_ADVANCE_PC)
>>> - {
>>> - /* If linker relaxation is enabled then the distance between the two
>>> - symbols in the frag->fr_symbol expression might change. Hence we
>>> - cannot rely upon the value computed by resolve_symbol_value.
>>> - Instead we leave the expression unfinalized and allow
>>> - emit_fixed_inc_line_addr to create a fixup (which later becomes a
>>> - relocation) that will allow the linker to correctly compute the
>>> - actual address difference. We have to use a fixed line advance for
>>> - this as we cannot (easily) relocate leb128 encoded values. */
>>> - int saved_finalize_syms = finalize_syms;
>>> -
>>> - finalize_syms = 0;
>>> - addr_diff = resolve_symbol_value (frag->fr_symbol);
>>> - finalize_syms = saved_finalize_syms;
>>> - }
>>> - else
>>> - addr_diff = resolve_symbol_value (frag->fr_symbol);
>>> + /* If linker relaxation is enabled then the distance between the two
>>> + symbols in the frag->fr_symbol expression might change. Hence we
>>> + cannot rely upon the value computed by resolve_symbol_value.
>>> + Instead we leave the expression unfinalized and allow
>>> + emit_fixed_inc_line_addr to create a fixup (which later becomes a
>>> + relocation) that will allow the linker to correctly compute the
>>> + actual address difference. We have to use a fixed line advance for
>>> + this as we cannot (easily) relocate leb128 encoded values. */
>>> + int saved_finalize_syms = finalize_syms;
>>> + finalize_syms = 0;
>>> + addr_diff = resolve_symbol_value (frag->fr_symbol);
>>> + finalize_syms = saved_finalize_syms;
>>> /* fr_var carries the max_chars that we created the fragment with.
>>> fr_subtype carries the current expected length. We must, of
>>> course, have allocated enough memory earlier. */
>>> gas_assert (frag->fr_var >= (int) frag->fr_subtype);
>>> - if (DWARF2_USE_FIXED_ADVANCE_PC)
>>> + if (DWARF2_USE_FIXED_ADVANCE_PC_FRAG (frag))
>>> emit_fixed_inc_line_addr (frag->fr_offset, addr_diff, frag,
>>> frag->fr_literal + frag->fr_fix,
>>> frag->fr_subtype);
>>> @@ -2110,7 +2110,8 @@ process_entries (segT seg, struct line_entry *e)
>>> out_set_addr (lab);
>>> out_inc_line_addr (line_delta, 0);
>>> }
>>> - else if (frag == last_frag && ! DWARF2_USE_FIXED_ADVANCE_PC)
>>> + else if (frag == last_frag
>>> + && ! DWARF2_USE_FIXED_ADVANCE_PC (last_lab, lab))
>>> out_inc_line_addr (line_delta, frag_ofs - last_frag_ofs);
>>> else
>>> relax_inc_line_addr (line_delta, lab, last_lab);
>>> @@ -2127,7 +2128,7 @@ process_entries (segT seg, struct line_entry *e)
>>> /* Emit a DW_LNE_end_sequence for the end of the section. */
>>> frag = last_frag_for_seg (seg);
>>> frag_ofs = get_frag_fix (frag, seg);
>>> - if (frag == last_frag && ! DWARF2_USE_FIXED_ADVANCE_PC)
>>> + if (frag == last_frag && ! DWARF2_USE_FIXED_ADVANCE_PC (last_lab, lab))
>>> out_inc_line_addr (INT_MAX, frag_ofs - last_frag_ofs);
>>> else
>>> {
>>> diff --git a/gas/testsuite/gas/elf/dwarf-5-irp.d b/gas/testsuite/gas/elf/dwarf-5-irp.d
>>> index a4f01355db3..781b2a32aaa 100644
>>> --- a/gas/testsuite/gas/elf/dwarf-5-irp.d
>>> +++ b/gas/testsuite/gas/elf/dwarf-5-irp.d
>>> @@ -5,8 +5,7 @@
>>> # The bfin target does not allow .subsection with an equated symbol as operand.
>>> # The d30v target emits sufficiently different debug info, apparently also covering padding it inserts.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am33*-* bfin-* cr16-* crx-* d30v-* ft32-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am33*-* bfin-* cr16-* crx-* d30v-* ft32-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Raw dump of debug contents .*
>>> #...
>>> diff --git a/gas/testsuite/gas/elf/dwarf-5-loc0.d b/gas/testsuite/gas/elf/dwarf-5-loc0.d
>>> index 9338271c0eb..9439d103b1f 100644
>>> --- a/gas/testsuite/gas/elf/dwarf-5-loc0.d
>>> +++ b/gas/testsuite/gas/elf/dwarf-5-loc0.d
>>> @@ -3,8 +3,7 @@
>>> #name: DWARF5 .loc 0
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Contents of the \.debug_line section:
>>> diff --git a/gas/testsuite/gas/elf/dwarf-5-macro-include.d b/gas/testsuite/gas/elf/dwarf-5-macro-include.d
>>> index c39425aa8c9..32ea6386992 100644
>>> --- a/gas/testsuite/gas/elf/dwarf-5-macro-include.d
>>> +++ b/gas/testsuite/gas/elf/dwarf-5-macro-include.d
>>> @@ -4,7 +4,7 @@
>>> # The am33 cr16 crx ft32 mn10* msp430 nds32* and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The d30v target emits sufficiently different debug info, apparently also covering padding it inserts.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -#xfail: am33*-* cr16-* crx-* d30v-* ft32-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am33*-* cr16-* crx-* d30v-* ft32-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Raw dump of debug contents .*
>>> #...
>>> diff --git a/gas/testsuite/gas/elf/dwarf-5-macro.d b/gas/testsuite/gas/elf/dwarf-5-macro.d
>>> index b2613bd1c16..794e17a575e 100644
>>> --- a/gas/testsuite/gas/elf/dwarf-5-macro.d
>>> +++ b/gas/testsuite/gas/elf/dwarf-5-macro.d
>>> @@ -4,7 +4,7 @@
>>> # The am33 cr16 crx ft32 mn10* msp430 nds32* and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The d30v target emits sufficiently different debug info, apparently also covering padding it inserts.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -#xfail: am33*-* cr16-* crx-* d30v-* ft32-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am33*-* cr16-* crx-* d30v-* ft32-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Raw dump of debug contents .*
>>> #...
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-11.d b/gas/testsuite/gas/elf/dwarf2-11.d
>>> index 44f5cd18ec6..2c30e55c695 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-11.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-11.d
>>> @@ -3,8 +3,7 @@
>>> #name: DWARF2 11
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Contents of the \.debug_line section:
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-15.d b/gas/testsuite/gas/elf/dwarf2-15.d
>>> index 3ec9f2785a7..939c61598cb 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-15.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-15.d
>>> @@ -3,8 +3,7 @@
>>> #name: DWARF2 15
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Hex dump of section '\.rodata':
>>> 0x00000000 01 *.*
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-16.d b/gas/testsuite/gas/elf/dwarf2-16.d
>>> index 32b57763137..8e35d493619 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-16.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-16.d
>>> @@ -4,8 +4,7 @@
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The mep target tries to relay code sections which breaks symbolic view computations.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* mep-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mep-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Hex dump of section '\.rodata':
>>> 0x00000000 01 *.*
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-17.d b/gas/testsuite/gas/elf/dwarf2-17.d
>>> index 4c2f2e3999e..881477cf95b 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-17.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-17.d
>>> @@ -4,8 +4,7 @@
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The mep target tries to relay code sections which breaks symbolic view computations.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* loongarch*-* mep-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mep-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Hex dump of section '\.rodata':
>>> 0x00000000 00 *.*
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-18.d b/gas/testsuite/gas/elf/dwarf2-18.d
>>> index 18157c634a5..fbaebaa9019 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-18.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-18.d
>>> @@ -3,8 +3,7 @@
>>> #name: DWARF2 18
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Hex dump of section '\.rodata':
>>> 0x00000000 0100 *.*
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-19.d b/gas/testsuite/gas/elf/dwarf2-19.d
>>> index 133294affe7..55d0caf4cb1 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-19.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-19.d
>>> @@ -4,8 +4,7 @@
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The mep targets turns some view computations into complex relocations.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* mep-* loongarch*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mep-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Hex dump of section '\.rodata':
>>> 0x00000000 01000102 *.*
>>> diff --git a/gas/testsuite/gas/elf/dwarf2-5.d b/gas/testsuite/gas/elf/dwarf2-5.d
>>> index 1dd65732c50..bf1eeb5bbfd 100644
>>> --- a/gas/testsuite/gas/elf/dwarf2-5.d
>>> +++ b/gas/testsuite/gas/elf/dwarf2-5.d
>>> @@ -4,8 +4,7 @@
>>> # The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
>>> # The mep target tries to relay code sections which breaks symbolic view computations.
>>> # The riscv targets do not support the subtraction of symbols.
>>> -# The loongarch targets do not support the subtraction of symbols.
>>> -#xfail: am3*-* cr16-* crx-* ft32*-* loongarch*-* mep-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> +#xfail: am3*-* cr16-* crx-* ft32*-* mep-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
>>> Hex dump of section '\.rodata':
>>> 0x00000000 01010201 010203 *.*
>>> diff --git a/gas/testsuite/gas/lns/lns.exp b/gas/testsuite/gas/lns/lns.exp
>>> index 7a92c54a260..58c2235b628 100644
>>> --- a/gas/testsuite/gas/lns/lns.exp
>>> +++ b/gas/testsuite/gas/lns/lns.exp
>>> @@ -31,7 +31,6 @@ if { ![istarget s390*-*-*] } {
>>> || [istarget cr16-*-*]
>>> || [istarget crx-*-*]
>>> || [istarget ft32*-*]
>>> - || [istarget loongarch*-*-*]
>>> || [istarget mn10*-*-*]
>>> || [istarget msp430-*-*]
>>> || [istarget nds32*-*-*]
>>> diff --git a/gas/testsuite/gas/loongarch/relax-debug-line-opcode-norelax.d b/gas/testsuite/gas/loongarch/relax-debug-line-opcode-norelax.d
>>> new file mode 100644
>>> index 00000000000..c8be41feb82
>>> --- /dev/null
>>> +++ b/gas/testsuite/gas/loongarch/relax-debug-line-opcode-norelax.d
>>> @@ -0,0 +1,10 @@
>>> +#source: relax-debug-line-opcode.s
>>> +#as: -mno-relax
>>> +#readelf: -W -wl
>>> +
>>> +#...
>>> +.* Special opcode 62: advance Address by 4 to 0x4 and Line by 1 to 11
>>> +.* Special opcode 118: advance Address by 8 to 0xc and Line by 1 to 12
>>> +.* Special opcode 62: advance Address by 4 to 0x10 and Line by 1 to 13
>>> +.* Special opcode 118: advance Address by 8 to 0x18 and Line by 1 to 14
>>> +#pass
>>> diff --git a/gas/testsuite/gas/loongarch/relax-debug-line-opcode.d b/gas/testsuite/gas/loongarch/relax-debug-line-opcode.d
>>> new file mode 100644
>>> index 00000000000..9c707d97747
>>> --- /dev/null
>>> +++ b/gas/testsuite/gas/loongarch/relax-debug-line-opcode.d
>>> @@ -0,0 +1,25 @@
>>> +#source: relax-debug-line-opcode.s
>>> +#as: -mrelax
>>> +#readelf: -r -wl -W
>>> +
>>> +#...
>>> +Relocation section '\.rela\.debug_line' at offset .* contains 7 entries:
>>> +#...
>>> +.*R_LARCH_ADD16[ ]+[0-9]+.*
>>> +.*R_LARCH_SUB16[ ]+[0-9]+.*
>>> +.*R_LARCH_ADD16[ ]+[0-9]+.*
>>> +.*R_LARCH_SUB16[ ]+[0-9]+.*
>>> +#...
>>> +Raw dump of debug contents of section \.debug_line:
>>> +#...
>>> +.* Special opcode 62: advance Address by 4 to 0x4 and Line by 1 to 11
>>> +.* Advance Line by 1 to 12
>>> +.* Advance PC by fixed size amount [0-9]+ to 0x[0-9a-f]+
>>> +.* Copy .*
>>> +.* Special opcode 62: advance Address by 4 to 0x10 and Line by 1 to 13
>>> +.* Advance Line by 1 to 14
>>> +.* Advance PC by fixed size amount [0-9]+ to 0x[0-9a-f]+
>>> +.* Copy .*
>>> +.* Advance PC by [0-9]+ to 0x[0-9a-f]+
>>> +.* Extended opcode 1: End of Sequence
>>> +#pass
>>> diff --git a/gas/testsuite/gas/loongarch/relax-debug-line-opcode.s b/gas/testsuite/gas/loongarch/relax-debug-line-opcode.s
>>> new file mode 100644
>>> index 00000000000..276a823373c
>>> --- /dev/null
>>> +++ b/gas/testsuite/gas/loongarch/relax-debug-line-opcode.s
>>> @@ -0,0 +1,15 @@
>>> + # Test DWARF line encoding around linker-relaxable instructions.
>>> + .file 0 "test"
>>> + .text
>>> + .loc 0 10 0
>>> + nop # special opcode
>>> + .loc 0 11 0
>>> + call36 func # -mrelax: DW_LNS_fixed_advance_pc; -mno-relax: special opcode.
>>> + .loc 0 12 0
>>> + nop # special opcode
>>> + .loc 0 13 0
>>> + call36 func # -mrelax: DW_LNS_fixed_advance_pc; -mno-relax: special opcode.
>>> + .loc 0 14 0
>>> + nop # Advance PC
>>> +
>>> +.section .debug_line, "", @progbits