46 lines
918 B
Text
46 lines
918 B
Text
/*
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(c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
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See the copyright notice in the ACK home directory, in the file "Copyright".
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*/
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/* $Header$ */
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/*
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MULTIPLY AND DISMEMBER PARTS (FIF 4)
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*/
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#include "FP_types.h"
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#include "FP_shift.h"
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void
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fif4(p,x,y)
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SINGLE x,y;
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struct fif4_returns *p;
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{
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EXTEND e1,e2;
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extend(&y,&e1,sizeof(SINGLE));
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extend(&x,&e2,sizeof(SINGLE));
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/* do a multiply */
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mul_ext(&e1,&e2);
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e2 = e1;
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compact(&e2,&y,sizeof(SINGLE));
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if (e1.exp < 0) {
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p->ipart = 0;
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p->fpart = y;
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return;
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}
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if (e1.exp > 30 - SGL_M1LEFT) {
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p->ipart = y;
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p->fpart = 0;
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return;
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}
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b64_sft(&e1.mantissa, 63 - e1.exp);
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b64_sft(&e1.mantissa, e1.exp - 63); /* "loose" low order bits */
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compact(&e1,&(p->ipart),sizeof(SINGLE));
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extend(&(p->ipart), &e2, sizeof(SINGLE));
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extend(&y, &e1, sizeof(SINGLE));
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sub_ext(&e1, &e2);
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compact(&e1, &(p->fpart), sizeof(SINGLE));
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}
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