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@ -1,10 +1,13 @@
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#include "fmt.h"
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#include "fmt.h"
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unsigned int fmt_double(char *dest, double d,int maxlen,int prec) {
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unsigned int fmt_double(char *dest, double d,int maxlen,int prec) {
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unsigned long long *x=(unsigned long long *)&d;
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union {
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double d;
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unsigned long long x;
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} __u = { .d=d, };
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/* step 1: extract sign, mantissa and exponent */
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/* step 1: extract sign, mantissa and exponent */
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signed int s=*x>>63;
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signed int s=__u.x>>63;
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signed long e=((*x>>52)&((1<<11)-1))-1023;
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signed long e=((__u.x>>52)&((1<<11)-1))-1023;
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/* unsigned long long m=*x & ((1ull<<52)-1); */
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/* unsigned long long m=*x & ((1ull<<52)-1); */
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/* step 2: exponent is base 2, compute exponent for base 10 */
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/* step 2: exponent is base 2, compute exponent for base 10 */
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signed long e10=1+(long)(e*0.30102999566398119802); /* log10(2) */
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signed long e10=1+(long)(e*0.30102999566398119802); /* log10(2) */
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