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Fixed behaviour of C++ <bit> #585

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Merged
mateoconlechuga merged 1 commit into from
Apr 11, 2025
Merged

Fixed behaviour of C++ <bit> #585

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42 changes: 18 additions & 24 deletions src/libcxx/include/bit
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Original file line number Diff line number Diff line change
Expand Up @@ -289,32 +289,32 @@ int bit_width(_Tp __t) noexcept;

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
int bit_width(unsigned char __t) noexcept {
return 8 - __ez80_clzc(__t);
return std::numeric_limits<unsigned char>::digits- __ez80_clzc(__t);
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
int bit_width(unsigned short __t) noexcept {
return 16 - __builtin_clzs(__t);
return std::numeric_limits<unsigned short>::digits - __builtin_clzs(__t);
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
int bit_width(unsigned int __t) noexcept {
return 24 - __builtin_clz(__t);
return std::numeric_limits<unsigned int>::digits - __builtin_clz(__t);
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
int bit_width(unsigned long __t) noexcept {
return 32 - __builtin_clzl(__t);
return std::numeric_limits<unsigned long>::digits - __builtin_clzl(__t);
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
int bit_width(unsigned __int48 __t) noexcept {
return 48 - __ez80_clzi48(__t);
return std::numeric_limits<unsigned __int48>::digits - __ez80_clzi48(__t);
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
int bit_width(unsigned long long __t) noexcept {
return 64 - __builtin_clzll(__t);
return std::numeric_limits<unsigned long long>::digits - __builtin_clzll(__t);
}

//------------------------------------------------------------------------------
Expand All @@ -327,49 +327,43 @@ _Tp bit_ceil(_Tp __t) noexcept;
template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
unsigned char bit_ceil(unsigned char __t) noexcept {
return
(static_cast<signed char>(__t) > 0)
? (static_cast<unsigned char>(1) << bit_width<unsigned char>(__t - 1))
: ((__t == 0) ? 1 : 0);
(__t <= static_cast<unsigned char>(std::numeric_limits<signed char>::min()))
? ((__t != 0) ? (static_cast<unsigned char>(1) << bit_width<unsigned char>(__t - 1)) : 1) : 0;
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
unsigned short bit_ceil(unsigned short __t) noexcept {
return
(static_cast<signed short>(__t) > 0)
? (static_cast<unsigned short>(1) << bit_width<unsigned short>(__t - 1))
: ((__t == 0) ? 1 : 0);
(__t <= static_cast<unsigned short>(std::numeric_limits<signed short>::min()))
? ((__t != 0) ? (static_cast<unsigned short>(1) << bit_width<unsigned short>(__t - 1)) : 1) : 0;
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
unsigned int bit_ceil(unsigned int __t) noexcept {
return
(static_cast<signed int>(__t) > 0)
? (static_cast<unsigned int>(1) << bit_width<unsigned int>(__t - 1))
: ((__t == 0) ? 1 : 0);
(__t <= static_cast<unsigned int>(std::numeric_limits<signed int>::min()))
? ((__t != 0) ? (static_cast<unsigned int>(1) << bit_width<unsigned int>(__t - 1)) : 1) : 0;
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
unsigned long bit_ceil(unsigned long __t) noexcept {
return
(static_cast<signed long>(__t) > 0)
? (static_cast<unsigned long>(1) << bit_width<unsigned long>(__t - 1))
: ((__t == 0) ? 1 : 0);
(__t <= static_cast<unsigned long>(std::numeric_limits<signed long>::min()))
? ((__t != 0) ? (static_cast<unsigned long>(1) << bit_width<unsigned long>(__t - 1)) : 1) : 0;
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
unsigned __int48 bit_ceil(unsigned __int48 __t) noexcept {
return
(static_cast<signed __int48>(__t) > 0)
? (static_cast<unsigned __int48>(1) << bit_width<unsigned __int48>(__t - 1))
: ((__t == 0) ? 1 : 0);
(__t <= static_cast<unsigned __int48>(std::numeric_limits<signed __int48>::min()))
? ((__t != 0) ? (static_cast<unsigned __int48>(1) << bit_width<unsigned __int48>(__t - 1)) : 1) : 0;
}

template <> _EZCXX_NODISCARD _EZCXX_INLINE constexpr
unsigned long long bit_ceil(unsigned long long __t) noexcept {
return
(static_cast<signed long long>(__t) > 0)
? (static_cast<unsigned long long>(1) << bit_width<unsigned long long>(__t - 1))
: ((__t == 0) ? 1 : 0);
(__t <= static_cast<unsigned long long>(std::numeric_limits<signed long long>::min()))
? ((__t != 0) ? (static_cast<unsigned long long>(1) << bit_width<unsigned long long>(__t - 1)) : 1) : 0;
}

//------------------------------------------------------------------------------
Expand Down
81 changes: 69 additions & 12 deletions test/standalone/stdbit/src/data.asm
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Original file line number Diff line number Diff line change
Expand Up @@ -16,20 +16,77 @@ _zero_u48:
_zero_u64:
db $00, $00, $00, $00, $00, $00, $00, $00

public _ones_u8
public _ones_u16
public _ones_u24
public _ones_u32
public _ones_u48
public _ones_u64
_ones_u8:
_ones_u16:
_ones_u24:
_ones_u32:
_ones_u48:
_ones_u64:
public _one_u8
public _one_u16
public _one_u24
public _one_u32
public _one_u48
public _one_u64
_one_u8:
_one_u16:
_one_u24:
_one_u32:
_one_u48:
_one_u64:
db $01, $00, $00, $00, $00, $00, $00, $00

public _umax_u8
public _umax_u16
public _umax_u24
public _umax_u32
public _umax_u48
public _umax_u64
_umax_u8:
_umax_u16:
_umax_u24:
_umax_u32:
_umax_u48:
_umax_u64:
db $FF, $FF, $FF, $FF, $FF, $FF, $FF, $FF

public _smin_u8
public _smin_u16
public _smin_u24
public _smin_u32
public _smin_u48
public _smin_u64
_smin_u64:
db $00
db $00
_smin_u48:
db $00
db $00
_smin_u32:
db $00
_smin_u24:
db $00
_smin_u16:
db $00
_smin_u8:
db $80

public _smax_u8
public _smax_u16
public _smax_u24
public _smax_u32
public _smax_u48
public _smax_u64
_smax_u64:
db $FF
db $FF
_smax_u48:
db $FF
db $FF
_smax_u32:
db $FF
_smax_u24:
db $FF
_smax_u16:
db $FF
_smax_u8:
db $7F


public _val_0
_val_0:
db 0
Expand Down
33 changes: 27 additions & 6 deletions test/standalone/stdbit/src/data.h
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Original file line number Diff line number Diff line change
Expand Up @@ -17,12 +17,33 @@ extern uint32_t zero_u32;
extern uint48_t zero_u48;
extern uint64_t zero_u64;

extern uint8_t ones_u8;
extern uint16_t ones_u16;
extern uint24_t ones_u24;
extern uint32_t ones_u32;
extern uint48_t ones_u48;
extern uint64_t ones_u64;
extern uint8_t one_u8;
extern uint16_t one_u16;
extern uint24_t one_u24;
extern uint32_t one_u32;
extern uint48_t one_u48;
extern uint64_t one_u64;

extern uint8_t umax_u8;
extern uint16_t umax_u16;
extern uint24_t umax_u24;
extern uint32_t umax_u32;
extern uint48_t umax_u48;
extern uint64_t umax_u64;

extern uint8_t smin_u8;
extern uint16_t smin_u16;
extern uint24_t smin_u24;
extern uint32_t smin_u32;
extern uint48_t smin_u48;
extern uint64_t smin_u64;

extern uint8_t smax_u8;
extern uint16_t smax_u16;
extern uint24_t smax_u24;
extern uint32_t smax_u32;
extern uint48_t smax_u48;
extern uint64_t smax_u64;

extern uint8_t val_0;
extern uint8_t val_1;
Expand Down
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