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#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
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