diff options
Diffstat (limited to 'src/libmp/port/mpvecadd.c')
-rw-r--r-- | src/libmp/port/mpvecadd.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/src/libmp/port/mpvecadd.c b/src/libmp/port/mpvecadd.c new file mode 100644 index 00000000..98fdcc90 --- /dev/null +++ b/src/libmp/port/mpvecadd.c @@ -0,0 +1,35 @@ +#include "os.h" +#include <mp.h> +#include "dat.h" + +// prereq: alen >= blen, sum has at least blen+1 digits +void +mpvecadd(mpdigit *a, int alen, mpdigit *b, int blen, mpdigit *sum) +{ + int i, carry; + mpdigit x, y; + + carry = 0; + for(i = 0; i < blen; i++){ + x = *a++; + y = *b++; + x += carry; + if(x < carry) + carry = 1; + else + carry = 0; + x += y; + if(x < y) + carry++; + *sum++ = x; + } + for(; i < alen; i++){ + x = *a++ + carry; + if(x < carry) + carry = 1; + else + carry = 0; + *sum++ = x; + } + *sum = carry; +} |