[RFC] Add is_representable_as_float() and is_representable_as_int
#19308
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alexandre-daubois
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is_representable_as_float() and is_representable_as_intis_representable_as_float() and is_representable_as_int
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ext/standard/type.c
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| #if SIZEOF_ZEND_LONG == 4 | ||
| return true; | ||
| #else | ||
| if (lval >= -9007199254740992LL && lval <= 9007199254740992LL) { |
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Nit:
| if (lval >= -9007199254740992LL && lval <= 9007199254740992LL) { | |
| if (lval >= -(INT64_C(1)<<53) && lval <= INT64_C(1)<<53) { |
and similarly for other literals
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It might be outdated if #19308 (comment) is validated 🙂
ext/standard/type.c
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| return true; | ||
| } | ||
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| if (abs_val > 9007199254740992ULL) { |
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Nit: condition is always true?
ext/standard/type.c
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| return true; | ||
| } | ||
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| zend_ulong abs_val = (zend_ulong)(lval < 0 ? -lval : lval); |
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This is undefined behavior with lval == ZEND_LONG_MIN
ext/standard/type.c
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| #if SIZEOF_ZEND_LONG == 4 | ||
| return true; | ||
| #else | ||
| if (lval >= -9007199254740992LL && lval <= 9007199254740992LL) { |
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What am I missing? Can't this entire else block just be return (zend_long) (double) lval == lval; ?
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Ah I guess UB... Can't we workaround that, the one liner is so much easier and prettier
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I actually changed the function with the oneliner. I also added a test case with PHP_INT_MIN. I think it's actually good? I think the undefined behavior is not relevant anymore with the one-liner as we don't manipulate things manually
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RFC: https://wiki.php.net/rfc/is-representable-as-float-int