diff options
author | Kyle Gunger <kgunger12@gmail.com> | 2024-05-06 02:10:26 -0400 |
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committer | Kyle Gunger <kgunger12@gmail.com> | 2024-05-06 02:10:26 -0400 |
commit | 626b54c05ab5a1ddee4dff66d4e2dc9a7053af3e (patch) | |
tree | 1a0de9db5895913a6679a1da27ddcc4ea1267a20 /src/types.c | |
parent | e6c126856c7eb9e72a3640d4b3ab5000ac2494ab (diff) |
Some more float conversion
Diffstat (limited to 'src/types.c')
-rw-r--r-- | src/types.c | 88 |
1 files changed, 57 insertions, 31 deletions
diff --git a/src/types.c b/src/types.c index 8fda424..e46a283 100644 --- a/src/types.c +++ b/src/types.c @@ -65,7 +65,7 @@ OSMFloatBreakdown _osm_ieee754_enlarge(uint64_t d, uint16_t m_len, uint16_t f_le // Denormal numbers (TODO) out.mantissa = OSM_FLOAT_EXPO_BIAS - bias; if (OSM_FLOAT_FRAC_LEN) - out.fraction = out.fraction << (OSM_FLOAT_FRAC_LEN - f_len); // corrected fraction based on difference in bit lengths + out.fraction = out.fraction << (OSM_FLOAT_FRAC_LEN - f_len); // corrected fraction based on difference in bit lengths bias = (uint16_t) ceil(log2(out.fraction)); } @@ -145,13 +145,41 @@ int8_t _osm_is_infinity(const OSMFloatBreakdown b) /// Handle NaN double _osm_ieee754_nan(OSMFloatBreakdown b, uint16_t m_len, uint16_t f_len) { + uint64_t out = 0; + uint64_t mask = (1 << m_len) - 1; + + // sign + out |= b.sign << (m_len + f_len); + // mantissa + out |= mask << f_len; + + // fraction + if (f_len >= OSM_FLOAT_FRAC_LEN) + out |= b.fraction << (f_len - OSM_FLOAT_FRAC_LEN); + else + out |= b.fraction >> (OSM_FLOAT_FRAC_LEN - f_len); + + // Make sure it's still nan just in case all the + // fraction bits got cleared + mask = (1 << f_len) - 1; + if ((out & mask) == 0) + out |= 1; + +#ifdef _OSM_FLOAT_USE_HIGH_BITS + out = out << (64 - (m_len + f_len + 1)); +#endif + return *(double *)&out; } /// Handle subnormal numbers double _osm_ieee754_subnormal(OSMFloatBreakdown b, uint16_t m_len, uint16_t f_len) { // TODO - return 0; + uint64_t out = 0; +#ifdef _OSM_FLOAT_USE_HIGH_BITS + out = out << (64 - (m_len + f_len + 1)); +#endif + return *(double *)&out; } /** @@ -160,51 +188,51 @@ double _osm_ieee754_subnormal(OSMFloatBreakdown b, uint16_t m_len, uint16_t f_le */ double _osm_ieee754_assemble(OSMFloatBreakdown b, uint16_t m_len, uint16_t f_len) { + + if (_osm_is_nan(b)) + return _osm_ieee754_nan(b, m_len, f_len); + else if (b.mantissa == 0) + return _osm_ieee754_subnormal(b, m_len, f_len); + uint64_t out = 0; // Sign (assumed to be at end) out |= b.sign << (m_len + f_len); - - if (b.mantissa == 0 || ) - { - // denormal numbers (TODO) - return *(double *)&out; - } // Mantissa mask uint64_t mask = (1 << m_len) - 1; - if (_osm_is_nan(b)) - { - // Handle NaN - out |= mask << f_len; - if (f_len >= OSM_FLOAT_FRAC_LEN) - out |= b.fraction << (f_len - OSM_FLOAT_FRAC_LEN); - else - out |= b.fraction >> (OSM_FLOAT_FRAC_LEN - f_len); - - // Make sure it's still nan just in case all the - // fraction bits got cleared - mask = (1 << f_len) - 1; - if ((out & mask) == 0) - out |= 1; - - return *(double *)&out; - } - // Handle mantissa uint64_t bias = mask >> 1; if (b.mantissa > OSM_FLOAT_EXPO_BIAS) { b.mantissa -= OSM_FLOAT_EXPO_BIAS; b.mantissa += bias; + if (b.mantissa >= mask) + { + // Create infinity + out |= mask << f_len; +#ifdef _OSM_FLOAT_USE_HIGH_BITS + out = out << (64 - (m_len + f_len + 1)); +#endif + return *(double *)&out; + } } else { b.mantissa = OSM_FLOAT_EXPO_BIAS - b.mantissa; b.mantissa = bias - b.mantissa; + + if (b.mantissa >= mask || b.mantissa == 0) + { + // wrapped around, should create subnormal + return _osm_ieee754_subnormal(b, m_len, f_len); + } } + // write mantissa + out |= (b.mantissa & mask) << f_len; + // Fraction (assumed to be low bits) mask = (1 << f_len) - 1; @@ -213,9 +241,6 @@ double _osm_ieee754_assemble(OSMFloatBreakdown b, uint16_t m_len, uint16_t f_len else out |= b.fraction >> (OSM_FLOAT_FRAC_LEN - f_len); - if ( && (out & mask) != 0) - out &= ~mask; - #ifdef _OSM_FLOAT_USE_HIGH_BITS out = out << (64 - (m_len + f_len + 1)); #endif @@ -231,7 +256,7 @@ double _osm_ieee754_assemble(OSMFloatBreakdown b, uint16_t m_len, uint16_t f_len * * WARNING: This code flushes out of bounds values to infinity * - * INFO: The fraction part of NaN values are set to 1 + * INFO: The fraction part of NaN values are set to 1 in some cases * * Should probably be updated with more formats if I was * feeling frisky. @@ -317,7 +342,8 @@ OSMColor osm_color_copy(const OSMColor *color) // char should be just one byte long anyways size_t len = strlen((char *)color->ex_names[i]) + 1; uint8_t *buf = malloc(strlen((char *)color->ex_names[i]) + 1); - memcpy(buf, color->ex_names[i], len); + memcpy(buf, color->ex_names[i], len + 1); + out.ex_names[i] = buf; } return out; |