diff options
Diffstat (limited to 'lib/zstd/zstd_internal.h')
| -rw-r--r-- | lib/zstd/zstd_internal.h | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/lib/zstd/zstd_internal.h b/lib/zstd/zstd_internal.h index 1a79fab9e13a..dac753397f86 100644 --- a/lib/zstd/zstd_internal.h +++ b/lib/zstd/zstd_internal.h @@ -127,7 +127,14 @@ static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG; * Shared functions to include for inlining *********************************************/ ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) { - memcpy(dst, src, 8); + /* + * zstd relies heavily on gcc being able to analyze and inline this + * memcpy() call, since it is called in a tight loop. Preboot mode + * is compiled in freestanding mode, which stops gcc from analyzing + * memcpy(). Use __builtin_memcpy() to tell gcc to analyze this as a + * regular memcpy(). + */ + __builtin_memcpy(dst, src, 8); } /*! ZSTD_wildcopy() : * custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */ @@ -137,13 +144,16 @@ ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length) const BYTE* ip = (const BYTE*)src; BYTE* op = (BYTE*)dst; BYTE* const oend = op + length; - /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388. +#if defined(GCC_VERSION) && GCC_VERSION >= 70000 && GCC_VERSION < 70200 + /* + * Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388. * Avoid the bad case where the loop only runs once by handling the * special case separately. This doesn't trigger the bug because it * doesn't involve pointer/integer overflow. */ if (length <= 8) return ZSTD_copy8(dst, src); +#endif do { ZSTD_copy8(op, ip); op += 8; |