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73 lines
762 B
C
73 lines
762 B
C
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typedef union {
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struct {
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unsigned int msw;
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unsigned int lsw;
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} s;
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long v;
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} u;
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long __mulsi3(u a, u b)
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{
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int s;
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long pp1;
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long pp2;
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long r;
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if (a.s.msw == 0 &&
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b.s.msw == 0)
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{
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return (long)a.s.lsw * b.s.lsw;
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}
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s = 0;
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if (a.v < 0)
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{
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s = 1;
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a.v = - a.v;
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}
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if (b.v < 0)
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{
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s = 1-s;
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b.v = - b.v;
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}
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pp1 = (long)a.s.lsw * b.s.lsw ;
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pp2 = (long)a.s.lsw * b.s.msw + (long)a.s.msw * b.s.lsw;
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pp1 += pp2 << 16;
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if (s)
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{
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pp1 = -pp1;
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}
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return pp1;
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}
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long __mulpsi3(long a, long b)
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{
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return a*b;
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}
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short
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__mulhi3(short a, short b)
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{
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int r;
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r = 0;
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while (a)
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{
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if (a & 1)
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{
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r += b;
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}
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b<<=1;
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a>>=1;
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}
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return r;
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}
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