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COMMON: Fix reading and writing of doubles when native double is 32-bit

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Marcus Comstedt 2022-06-27 10:45:28 +02:00 • committed by Eugene Sandulenko
parent ae84b42c28
commit 004758862e
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GPG key ID: 014D387312D34F08
1 changed files with 72 additions and 11 deletions
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83
common/endian.h
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@ -680,21 +680,82 @@ union SwapDouble {
};
#endif
#ifndef __DC__
STATIC_ASSERT(sizeof(double) == sizeof(uint64), Unexpected_size_of_double);
#endif
STATIC_ASSERT(sizeof(double) == sizeof(uint64) || sizeof(double) == sizeof(uint32), Unexpected_size_of_double);
template<size_t n> inline double READ_DOUBLE(const SwapDouble& sw);
template<size_t n> inline void WRITE_DOUBLE(SwapDouble &sw, double d);
// 64-bit double
template<> inline double READ_DOUBLE<sizeof(uint64)>(const SwapDouble& sd)
{
return sd.d;
}
template<> inline void WRITE_DOUBLE<sizeof(uint64)>(SwapDouble &sd, double d)
{
sd.d = d;
}
// 32-bit double
template<> inline double READ_DOUBLE<sizeof(uint32)>(const SwapDouble& sd)
{
SwapFloat sf;
uint32 e = (sd.u32.high >> 20) & 0x7ff;
if (e <= 896) {
// Too small for normalized, create a zero with the correct sign
// (FIXME: Create denormalized numbers instead when possible?)
sf.u32 = (sd.u32.high & 0x80000000U); // sign bit
return sf.f;
} else if(e >= 1151) {
// Overflow, infinity or NaN
if (e < 2047) {
// Overflow; make sure result is infinity and not NaN
sf.u32 = (sd.u32.high & 0x80000000U) | // sign bit
(255 << 23); // exponent
return sf.f;
}
e = 255;
} else
e -= 896;
sf.u32 = (sd.u32.high & 0x80000000U) | // sign bit
(e << 23) | // exponent
((sd.u32.high & 0xfffff) << 3) | (sd.u32.low >> 29); // mantissa
return sf.f;
}
template<> inline void WRITE_DOUBLE<sizeof(uint32)>(SwapDouble &sd, double d)
{
SwapFloat sf;
sf.f = d;
uint32 e = (sf.u32 >> 23) & 0xff;
if (!e) {
// Denormalized or zero, create a zero with the correct sign
// (FIXME: Convert denormalized 32-bit to normalized 64-bit?)
sd.u32.high = (sf.u32 & 0x80000000U); // sign bit
sd.u32.low = 0;
return;
} else if (e == 255) {
// Infinity or NaN
e = 2047;
} else
e += 896;
sd.u32.high = (sf.u32 & 0x80000000U) | // sign bit
(e << 20) | // exponent
((sf.u32 >> 3) & 0xfffff); // mantissa
sd.u32.low = sf.u32 << 29;
}
inline double READ_LE_FLOAT64(const void *ptr) {
SwapDouble swap;
const uint8 *b = (const uint8 *)ptr;
swap.u32.low = READ_LE_UINT32(b);
swap.u32.high = READ_LE_UINT32(b + 4);
return swap.d;
return READ_DOUBLE<sizeof(double)>(swap);
}
inline void WRITE_LE_FLOAT64(void *ptr, double value) {
SwapDouble swap;
swap.d = value;
WRITE_DOUBLE<sizeof(double)>(swap, value);
uint8 *b = (uint8 *)ptr;
WRITE_LE_UINT32(b, swap.u32.low);
WRITE_LE_UINT32(b + 4, swap.u32.high);
@ -705,12 +766,12 @@ inline double READ_BE_FLOAT64(const void *ptr) {
const uint8 *b = (const uint8 *)ptr;
swap.u32.high = READ_BE_UINT32(b);
swap.u32.low = READ_BE_UINT32(b + 4);
return swap.d;
return READ_DOUBLE<sizeof(double)>(swap);
}
inline void WRITE_BE_FLOAT64(void *ptr, double value) {
SwapDouble swap;
swap.d = value;
WRITE_DOUBLE<sizeof(double)>(swap, value);
uint8 *b = (uint8 *)ptr;
WRITE_BE_UINT32(b, swap.u32.high);
WRITE_BE_UINT32(b + 4, swap.u32.low);
@ -721,12 +782,12 @@ inline double READ_FPA_FLOAT64(const void *ptr) {
const uint8 *b = (const uint8 *)ptr;
swap.u32.high = READ_LE_UINT32(b);
swap.u32.low = READ_LE_UINT32(b + 4);
return swap.d;
return READ_DOUBLE<sizeof(double)>(swap);
}
inline void WRITE_FPA_FLOAT64(void *ptr, double value) {
SwapDouble swap;
swap.d = value;
WRITE_DOUBLE<sizeof(double)>(swap, value);
uint8 *b = (uint8 *)ptr;
WRITE_LE_UINT32(b, swap.u32.high);
WRITE_LE_UINT32(b + 4, swap.u32.low);
@ -735,12 +796,12 @@ inline void WRITE_FPA_FLOAT64(void *ptr, double value) {
inline double READ_FLOAT64(const void *ptr) {
SwapDouble swap;
swap.u64 = READ_UINT64(ptr);
return swap.d;
return READ_DOUBLE<sizeof(double)>(swap);
}
inline void WRITE_FLOAT64(void *ptr, double value) {
SwapDouble swap;
swap.d = value;
WRITE_DOUBLE<sizeof(double)>(swap, value);
WRITE_UINT64(ptr, swap.u64);
}