diff options
Diffstat (limited to 'src/corelib/global/qnumeric_p.h')
-rw-r--r-- | src/corelib/global/qnumeric_p.h | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/src/corelib/global/qnumeric_p.h b/src/corelib/global/qnumeric_p.h index dd59f97f8b..4a225b2599 100644 --- a/src/corelib/global/qnumeric_p.h +++ b/src/corelib/global/qnumeric_p.h @@ -231,7 +231,7 @@ QT_WARNING_POP // size_t. Implementations for 8- and 16-bit types will work but may not be as // efficient. Implementations for 64-bit may be missing on 32-bit platforms. -#if (defined(Q_CC_GNU) && (Q_CC_GNU >= 500) || (defined(Q_CC_INTEL) && !defined(Q_OS_WIN))) || QT_HAS_BUILTIN(__builtin_add_overflowx) +#if (defined(Q_CC_GNU) && (Q_CC_GNU >= 500) || (defined(Q_CC_INTEL) && !defined(Q_OS_WIN))) || QT_HAS_BUILTIN(__builtin_add_overflow) // GCC 5, ICC 18, and Clang 3.8 have builtins to detect overflows template <typename T> inline @@ -373,10 +373,18 @@ template <> inline bool add_overflow(unsigned v1, unsigned v2, unsigned *r) // 32-bit mul_overflow is fine with the generic code above -# if defined(Q_PROCESSOR_X86_64) template <> inline bool add_overflow(quint64 v1, quint64 v2, quint64 *r) -{ return _addcarry_u64(0, v1, v2, reinterpret_cast<unsigned __int64 *>(r)); } -# endif // x86-64 +{ +# if defined(Q_PROCESSOR_X86_64) + return _addcarry_u64(0, v1, v2, reinterpret_cast<unsigned __int64 *>(r)); +# else + uint low, high; + uchar carry = _addcarry_u32(0, unsigned(v1), unsigned(v2), &low); + carry = _addcarry_u32(carry, v1 >> 32, v2 >> 32, &high); + *r = (quint64(high) << 32) | low; + return carry; +# endif // !x86-64 +} # endif // MSVC X86 #endif // !GCC } |