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gcode_parse.c: get rid of the denominator variable in decfloat_to_int(). 

This allows for better optimisation and saves 100 bytes binary size
accordingly. For denominator = 1, the algorithm is also significantly
simpler.
This commit is contained in:
Markus Hitter 2011-04-11 01:23:36 +02:00
parent 6896aa5236
commit ee481864fa
1 changed files with 9 additions and 4 deletions
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13
gcode_parse.c
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@ -91,15 +91,20 @@ extern const uint32_t powers[]; // defined in sermsg.c
static int32_t decfloat_to_int(decfloat *df, uint32_t multiplicand, uint8_t divide_by_1000) {
uint32_t r = df->mantissa;
uint8_t e = df->exponent;
uint32_t denominator = divide_by_1000 ? 1000 : 1;
uint32_t rnew1, rnew2;
// e=1 means we've seen a decimal point but no digits after it, and e=2 means we've seen a decimal point with one digit so it's too high by one if not zero
if (e)
e--;
uint32_t rnew1 = r * (multiplicand / denominator);
uint32_t rnew2 = (r * (multiplicand % denominator) + (denominator / 2)) / denominator;
r = rnew1 + rnew2;
if (divide_by_1000) {
rnew1 = r * (multiplicand / 1000);
rnew2 = (r * (multiplicand % 1000) + (1000 / 2)) / 1000;
r = rnew1 + rnew2;
}
else {
r *= multiplicand;
}
if (e)
r = (r + powers[e] / 2) / powers[e];