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[/] [openrisc/] [trunk/] [gnu-src/] [newlib-1.17.0/] [newlib/] [libc/] [machine/] [h8500/] [mulsi3.c] - Blame information for rev 171

Line No.	Rev	Author	Line
1	148	jeremybenn
2			`typedef union {`
3			`struct {`
4			`unsigned int msw;`
5			`unsigned int lsw;`
6			`} s;`
7			`long v;`
8			`} u;`
9
10			`long __mulsi3(u a, u b)`
11			`{`
12			`int s;`
13			`long pp1;`
14			`long pp2;`
15			`long r;`
16
17			`if (a.s.msw == 0 &&`
18			`b.s.msw == 0)`
19			`{`
20			`return (long)a.s.lsw * b.s.lsw;`
21			`}`
22
23			`s = 0;`
24			`if (a.v < 0)`
25			`{`
26			`s = 1;`
27			`a.v = - a.v;`
28			`}`
29			`if (b.v < 0)`
30			`{`
31			`s = 1-s;`
32			`b.v = - b.v;`
33			`}`
34
35			`pp1 = (long)a.s.lsw * b.s.lsw ;`
36			`pp2 = (long)a.s.lsw * b.s.msw + (long)a.s.msw * b.s.lsw;`
37
38			`pp1 += pp2 << 16;`
39
40			`if (s)`
41			`{`
42			`pp1 = -pp1;`
43			`}`
44			`return pp1;`
45			`}`
46			`long __mulpsi3(long a, long b)`
47			`{`
48			`return a*b;`
49			`}`
50
51
52			`short`
53			`__mulhi3(short a, short b)`
54			`{`
55			`int r;`
56
57			`r = 0;`
58			`while (a)`
59			`{`
60			`if (a & 1)`
61			`{`
62			`r += b;`
63
64			`}`
65			`b<<=1;`
66			`a>>=1;`
67
68			`}`
69			`return r;`
70			`}`
71
72