Re: [PATCH] LoongArch: Support pointer guard on LoongArch32

LGTM

在 2026/8/24 17:44, mengqinggang 写道:
> Ping.
>
>
> 在 2026/8/10 16:44, mengqinggang 写道:
>> LoongArch32 Reduced has no rotri.d/rotri.w instructions.
>> Use slli.w/srli.w/or to synthesize the rotation on LoongArch32
>> and LoongArch32 Reduced.
>>
>> Reported-by: Haiyong Sun <[email protected]>
>> ---
>>   sysdeps/loongarch/__longjmp.S                 |  4 +-
>>   sysdeps/loongarch/setjmp.S                    |  4 +-
>>   .../sysv/linux/loongarch/pointer_guard-asm.h  | 44 +++++++++++++------
>>   3 files changed, 34 insertions(+), 18 deletions(-)
>>
>> diff --git a/sysdeps/loongarch/__longjmp.S 
>> b/sysdeps/loongarch/__longjmp.S
>> index 191f03320a..302cb6894a 100644
>> --- a/sysdeps/loongarch/__longjmp.S
>> +++ b/sysdeps/loongarch/__longjmp.S
>> @@ -23,9 +23,9 @@
>>   ENTRY (__longjmp)
>>   #ifdef PTR_MANGLE
>>       REG_L t0, a0, 0*SZREG
>> -    PTR_DEMANGLE (ra, t0, t1)
>> +    PTR_DEMANGLE (ra, t0, t1, t2)
>>       REG_L t0, a0, 1*SZREG
>> -    PTR_DEMANGLE2 (sp, t0, t1)
>> +    PTR_DEMANGLE2 (sp, t0, t1, t2)
>>   #else
>>       REG_L ra, a0, 0*SZREG
>>       REG_L sp, a0, 1*SZREG
>> diff --git a/sysdeps/loongarch/setjmp.S b/sysdeps/loongarch/setjmp.S
>> index 591e0d2709..58c1ee02b2 100644
>> --- a/sysdeps/loongarch/setjmp.S
>> +++ b/sysdeps/loongarch/setjmp.S
>> @@ -31,9 +31,9 @@ END (setjmp)
>>     ENTRY (__sigsetjmp)
>>   #ifdef PTR_MANGLE
>> -    PTR_MANGLE (t0, ra, t1)
>> +    PTR_MANGLE (t0, ra, t1, t2)
>>       REG_S t0, a0, 0*SZREG
>> -    PTR_MANGLE2 (t0, sp, t1)
>> +    PTR_MANGLE2 (t0, sp, t1, t2)
>>       REG_S t0, a0, 1*SZREG
>>   #else
>>       REG_S ra, a0, 0*SZREG
>> diff --git a/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h 
>> b/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
>> index 24e27e4092..006b713f9c 100644
>> --- a/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
>> +++ b/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
>> @@ -24,24 +24,40 @@
>>         || (!defined SHARED && (IS_IN (libc) \
>>         || IS_IN (libpthread))))
>>   #  define PTR_MANGLE_LOAD(guard) \
>> -  LOAD_LOCAL (guard, __pointer_chk_guard_local);
>> +    LOAD_LOCAL (guard, __pointer_chk_guard_local);
>>   # else
>>   #  define PTR_MANGLE_LOAD(guard) \
>> -  LOAD_GLOBAL (guard, __pointer_chk_guard);
>> +    LOAD_GLOBAL (guard, __pointer_chk_guard);
>>   # endif
>> -# define PTR_MANGLE(dst, src, guard) \
>> -  PTR_MANGLE_LOAD (guard); \
>> -  PTR_MANGLE2 (dst, src, guard);
>> -# define PTR_DEMANGLE(dst, src, guard) \
>> -  PTR_MANGLE_LOAD (guard); \
>> -  PTR_DEMANGLE2 (dst, src, guard);
>> +
>> +# define PTR_MANGLE(dst, src, guard, tmp) \
>> +    PTR_MANGLE_LOAD (guard); \
>> +    PTR_MANGLE2 (dst, src, guard, tmp);
>> +# define PTR_DEMANGLE(dst, src, guard, tmp) \
>> +    PTR_MANGLE_LOAD (guard); \
>> +    PTR_DEMANGLE2 (dst, src, guard, tmp);
>> +
>> +# if __loongarch_grlen == 64
>>   /* Use PTR_MANGLE2 for efficiency if guard is already loaded. */
>> -# define PTR_MANGLE2(dst, src, guard) \
>> -  xor  dst, src, guard; \
>> -  rotri.d  dst, dst, 47;
>> -# define PTR_DEMANGLE2(dst, src, guard) \
>> -  rotri.d  src, src, 17; \
>> -  xor  dst, src, guard;
>> +#  define PTR_MANGLE2(dst, src, guard, tmp) \
>> +    xor      tmp, src, guard; \
>> +    rotri.d      dst, tmp, 47;
>> +#  define PTR_DEMANGLE2(dst, src, guard, tmp) \
>> +    rotri.d      tmp, src, 17; \
>> +    xor      dst, tmp, guard;
>> +# elif __loongarch_grlen == 32 /* __loongarch_grlen == 64 */
>> +#  define PTR_MANGLE2(dst, src, guard, tmp) \
>> +    xor      tmp, src, guard; \
>> +    slli.w      dst, tmp, 9; \
>> +    srli.w      tmp, tmp, 23; \
>> +    or      dst, dst, tmp;
>> +#  define PTR_DEMANGLE2(dst, src, guard, tmp) \
>> +    srli.w      tmp, src, 9; \
>> +    slli.w      src, src, 23; \
>> +    or      tmp, tmp, src; \
>> +    xor      dst, tmp, guard;
>> +# endif /* __loongarch_grlen == 64 */
>> +
>>   #endif
>>     #endif /* POINTER_GUARD_ASM_H */