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Remove x86 bit test optimization

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This is undefined behavior and we cannot rely on it. Additionally it
breaks builds using undefined behavior sanitizers.
This commit is contained in:
Nikita Popov 2019-03-18 10:12:15 +01:00
parent 00cfa1a367
commit c4464526cd
1 changed files with 2 additions and 6 deletions
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8
Zend/zend_portability.h
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@ -440,12 +440,8 @@ char *alloca();
#define MAX(a, b) (((a)>(b))?(a):(b))
#define MIN(a, b) (((a)<(b))?(a):(b))
/* x86 instructions BT, SHL, SHR don't require masking */
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) || defined(ZEND_WIN32)
# define ZEND_BIT_TEST(bits, bit) (((bits)[(bit) / (sizeof((bits)[0])*8)] >> (bit)) & 1)
#else
# define ZEND_BIT_TEST(bits, bit) (((bits)[(bit) / (sizeof((bits)[0])*8)] >> ((bit) & (sizeof((bits)[0])*8-1))) & 1)
#endif
#define ZEND_BIT_TEST(bits, bit) \
(((bits)[(bit) / (sizeof((bits)[0])*8)] >> ((bit) & (sizeof((bits)[0])*8-1))) & 1)
/* We always define a function, even if there's a macro or expression we could
* alias, so that using it in contexts where we can't make function calls