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Needless IEEE754 conversion, float pointer cast instead

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This commit is contained in:
jakubovsky
2012-08-21 06:08:23 +02:00
committed by Stuart Longland
parent 716d712314
commit 7e1be93dbd
1 changed files with 2 additions and 33 deletions
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35
mbus/mbus-protocol.c
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@ -649,41 +649,10 @@ mbus_data_int_encode(unsigned char *int_data, size_t int_data_size, int value)
float
mbus_data_float_decode(unsigned char *float_data)
{
float val = 0.0f;
long temp = 0, fraction;
int sign,exponent;
size_t i;
if (float_data)
{
for (i = 4; i > 0; i--)
{
temp = (temp << 8) + float_data[i-1];
}
return *(float *) float_data;
// first bit = sign bit
sign = (temp >> 31) ? -1 : 1;
// decode 8 bit exponent
exponent = ((temp & 0x7F800000) >> 23) - 127;
// decode explicit 23 bit fraction
fraction = temp & 0x007FFFFF;
if ((exponent != -127) &&
(exponent != 128))
{
// normalized value, add bit 24
fraction |= 0x800000;
}
// calculate float value
val = (float) sign * fraction * pow(2.0f, -23.0f + exponent);
return val;
}
return -1.0;
return -1.0f;
}
//------------------------------------------------------------------------------