| #include "util/bit_packing.hh" |
| #include "util/exception.hh" |
| |
| #include <string.h> |
| |
| namespace util { |
| |
| namespace { |
| template <bool> struct StaticCheck {}; |
| template <> struct StaticCheck<true> { typedef bool StaticAssertionPassed; }; |
| |
| // If your float isn't 4 bytes, we're hosed. |
| typedef StaticCheck<sizeof(float) == 4>::StaticAssertionPassed FloatSize; |
| |
| } // namespace |
| |
| uint8_t RequiredBits(uint64_t max_value) { |
| if (!max_value) return 0; |
| uint8_t ret = 1; |
| while (max_value >>= 1) ++ret; |
| return ret; |
| } |
| |
| void BitPackingSanity() { |
| const FloatEnc neg1 = { -1.0 }, pos1 = { 1.0 }; |
| if ((neg1.i ^ pos1.i) != 0x80000000) UTIL_THROW(Exception, "Sign bit is not 0x80000000"); |
| char mem[57+8]; |
| memset(mem, 0, sizeof(mem)); |
| const uint64_t test57 = 0x123456789abcdefULL; |
| for (uint64_t b = 0; b < 57 * 8; b += 57) { |
| WriteInt57(mem, b, 57, test57); |
| } |
| for (uint64_t b = 0; b < 57 * 8; b += 57) { |
| if (test57 != ReadInt57(mem, b, 57, (1ULL << 57) - 1)) |
| UTIL_THROW(Exception, "The bit packing routines are failing for your architecture. Please send a bug report with your architecture, operating system, and compiler."); |
| } |
| // TODO: more checks. |
| } |
| |
| } // namespace util |