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tuklib_integer: Fix inefficient aligned_writeXXne

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The __builtin_assume_aligned was applied to the wrong argument which
made aligned writes worse on strict-align archs.

Aligned writes aren't used in liblzma, so this bug didn't matter in
this package; tuklib_integer.h is meant to be usable elsewhere too.
This commit is contained in:
Lasse Collin 2026-03-23 23:43:56 +02:00
parent 685538271e
commit 2faa141bdb
No known key found for this signature in database
GPG Key ID: 38EE757D69184620
1 changed files with 9 additions and 10 deletions
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19
src/common/tuklib_integer.h
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@ -643,11 +643,10 @@ write64le(uint8_t *buf, uint64_t num)
//
// __builtin_assume_aligned is support by GCC >= 4.7 and clang >= 3.6.
#ifdef HAVE___BUILTIN_ASSUME_ALIGNED
# define tuklib_memcpy_aligned(dest, src, size) \
memcpy(dest, __builtin_assume_aligned(src, size), size)
# define tuklib_assume_aligned(ptr, align) \
__builtin_assume_aligned(ptr, align)
#else
# define tuklib_memcpy_aligned(dest, src, size) \
memcpy(dest, src, size)
# define tuklib_assume_aligned(ptr, align) (ptr)
# ifndef TUKLIB_FAST_UNALIGNED_ACCESS
# define TUKLIB_USE_UNSAFE_ALIGNED_READS 1
# endif
@ -662,7 +661,7 @@ aligned_read16ne(const uint8_t *buf)
return *(const uint16_t *)buf;
#else
uint16_t num;
tuklib_memcpy_aligned(&num, buf, sizeof(num));
memcpy(&num, tuklib_assume_aligned(buf, sizeof(num)), sizeof(num));
return num;
#endif
}
@ -676,7 +675,7 @@ aligned_read32ne(const uint8_t *buf)
return *(const uint32_t *)buf;
#else
uint32_t num;
tuklib_memcpy_aligned(&num, buf, sizeof(num));
memcpy(&num, tuklib_assume_aligned(buf, sizeof(num)), sizeof(num));
return num;
#endif
}
@ -690,7 +689,7 @@ aligned_read64ne(const uint8_t *buf)
return *(const uint64_t *)buf;
#else
uint64_t num;
tuklib_memcpy_aligned(&num, buf, sizeof(num));
memcpy(&num, tuklib_assume_aligned(buf, sizeof(num)), sizeof(num));
return num;
#endif
}
@ -702,7 +701,7 @@ aligned_write16ne(uint8_t *buf, uint16_t num)
#ifdef TUKLIB_USE_UNSAFE_TYPE_PUNNING
*(uint16_t *)buf = num;
#else
tuklib_memcpy_aligned(buf, &num, sizeof(num));
memcpy(tuklib_assume_aligned(buf, sizeof(num)), &num, sizeof(num));
#endif
return;
}
@ -714,7 +713,7 @@ aligned_write32ne(uint8_t *buf, uint32_t num)
#ifdef TUKLIB_USE_UNSAFE_TYPE_PUNNING
*(uint32_t *)buf = num;
#else
tuklib_memcpy_aligned(buf, &num, sizeof(num));
memcpy(tuklib_assume_aligned(buf, sizeof(num)), &num, sizeof(num));
#endif
return;
}
@ -726,7 +725,7 @@ aligned_write64ne(uint8_t *buf, uint64_t num)
#ifdef TUKLIB_USE_UNSAFE_TYPE_PUNNING
*(uint64_t *)buf = num;
#else
tuklib_memcpy_aligned(buf, &num, sizeof(num));
memcpy(tuklib_assume_aligned(buf, sizeof(num)), &num, sizeof(num));
#endif
return;
}