51 lines
954 B
C
51 lines
954 B
C
/*
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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 8)
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*/
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#include "FP_types.h"
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#include "FP_shift.h"
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_double sbf8();
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struct fif8_returns {
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_double ipart;
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_double fpart;
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};
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fif8(p,x,y)
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_double x,y;
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struct fif8_returns *p;
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{
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EXTEND e1,e2;
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extend(&y,&e1,sizeof(_double));
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extend(&x,&e2,sizeof(_double));
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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(_double));
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if (e1.exp < 0) {
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p->ipart.__double[0] = 0;
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p->ipart.__double[1] = 0;
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p->fpart = y;
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return;
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}
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if (e1.exp > 62 - DBL_M1LEFT) {
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p->ipart = y;
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p->fpart.__double[0] = 0;
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p->fpart.__double[1] = 0;
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return;
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}
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b64_sft(&e1.m1, 63 - e1.exp);
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b64_sft(&e1.m1, e1.exp - 63); /* "loose" low order bits */
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compact(&e1, &(p->ipart), sizeof(DOUBLE));
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p->fpart = sbf8(p->ipart, y);
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}
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