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#include "pdefs.h"
#include "precision.h"
#include <string.h>
#ifdef ASM_16BIT
#include "asm16bit.h"
#endif
/*
* Multiply u by v (assumes normalized)
*/
precision pmul(u, v)
register precision v; /* register a5 on 68000 */
#ifdef ASM_16BIT
register precision u; /* register a4 */
{
#else
precision u;
{
digitPtr vPtr;
register digitPtr uPtr, wPtr, HiDigit;
register accumulator temp; /* 0 <= temp < base * base */ /* d7 */
register digit vdigit; /* d6 */
#endif
register digit hi; /* 0 <= hi < base */ /* d5 */
precision w;
(void) pparm(u);
(void) pparm(v);
/*
* Check for multiply by zero. Helps prevent wasted storage and -0
*/
if (peqz(u) || peqz(v)) {
w = palloc(1);
if (w == pUndef) return w;
w->sign = false;
w->value[0] = 0;
} else {
if (u->size < v->size) { /* u is biggest number (for inner loop speed) */
w = u; u = v; v = w;
}
w = palloc(u->size + v->size);
if (w == pUndef) return w;
w->sign = (u->sign != v->sign);
#ifndef ASM_16BIT
uPtr = u->value;
vPtr = v->value;
wPtr = w->value + u->size; /* this is correct! */
do {
*--wPtr = 0;
} while (wPtr > w->value);
vPtr = v->value;
HiDigit = u->value + u->size;
do {
uPtr = u->value;
wPtr = w->value + (vPtr - v->value);
hi = 0;
vdigit = *vPtr;
do {
temp = uMul(vdigit, *uPtr++); /* 0 <= temp <= (base-1)^2 */
temp += *wPtr; /* 0 <= temp <= base(base-1) */
temp += hi; /* 0 <= temp < base * base */
hi = divBase(temp); /* 0 <= hi < base */
*wPtr++ = modBase(temp);
} while (uPtr < HiDigit);
*wPtr++ = hi;
} while (++vPtr < v->value + v->size);
#else
hi = memmulw(w->value, u->value, u->size, v->value, v->size);
#endif
if (hi == 0) {
--(w->size); /* normalize */
}
}
pdestroy(u);
pdestroy(v);
return presult(w);
}
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