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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libcompiler_rt/udivmodti4.c	Lines:	0	77	0.0 %
Date:	2017-11-13	Branches:	0	48	0.0 %


/* ===-- udivmodti4.c - Implement __udivmodti4 -----------------------------===
 *
 *                    The LLVM Compiler Infrastructure
 *
 * This file is dual licensed under the MIT and the University of Illinois Open
 * Source Licenses. See LICENSE.TXT for details.
 *
 * ===----------------------------------------------------------------------===
 *
 * This file implements __udivmodti4 for the compiler_rt library.
 *
 * ===----------------------------------------------------------------------===
 */

#include "int_lib.h"

#ifdef CRT_HAS_128BIT

/* Effects: if rem != 0, *rem = a % b
 * Returns: a / b
 */

/* Translated from Figure 3-40 of The PowerPC Compiler Writer's Guide */

COMPILER_RT_ABI tu_int
__udivmodti4(tu_int a, tu_int b, tu_int* rem)
{
    const unsigned n_udword_bits = sizeof(du_int) * CHAR_BIT;
    const unsigned n_utword_bits = sizeof(tu_int) * CHAR_BIT;
    utwords n;
    n.all = a;
    utwords d;
    d.all = b;
    utwords q;
    utwords r;
    unsigned sr;
    /* special cases, X is unknown, K != 0 */
    if (n.s.high == 0)
    {
        if (d.s.high == 0)
        {
            /* 0 X
             * ---
             * 0 X
             */
            if (rem)
                *rem = n.s.low % d.s.low;
            return n.s.low / d.s.low;
        }
        /* 0 X
         * ---
         * K X
         */
        if (rem)
            *rem = n.s.low;
        return 0;
    }
    /* n.s.high != 0 */
    if (d.s.low == 0)
    {
        if (d.s.high == 0)
        {
            /* K X
             * ---
             * 0 0
             */
            if (rem)
                *rem = n.s.high % d.s.low;
            return n.s.high / d.s.low;
        }
        /* d.s.high != 0 */
        if (n.s.low == 0)
        {
            /* K 0
             * ---
             * K 0
             */
            if (rem)
            {
                r.s.high = n.s.high % d.s.high;
                r.s.low = 0;
                *rem = r.all;
            }
            return n.s.high / d.s.high;
        }
        /* K K
         * ---
         * K 0
         */
        if ((d.s.high & (d.s.high - 1)) == 0)     /* if d is a power of 2 */
        {
            if (rem)
            {
                r.s.low = n.s.low;
                r.s.high = n.s.high & (d.s.high - 1);
                *rem = r.all;
            }
            return n.s.high >> __builtin_ctzll(d.s.high);
        }
        /* K K
         * ---
         * K 0
         */
        sr = __builtin_clzll(d.s.high) - __builtin_clzll(n.s.high);
        /* 0 <= sr <= n_udword_bits - 2 or sr large */
        if (sr > n_udword_bits - 2)
        {
           if (rem)
                *rem = n.all;
            return 0;
        }
        ++sr;
        /* 1 <= sr <= n_udword_bits - 1 */
        /* q.all = n.all << (n_utword_bits - sr); */
        q.s.low = 0;
        q.s.high = n.s.low << (n_udword_bits - sr);
        /* r.all = n.all >> sr; */
        r.s.high = n.s.high >> sr;
        r.s.low = (n.s.high << (n_udword_bits - sr)) | (n.s.low >> sr);
    }
    else  /* d.s.low != 0 */
    {
        if (d.s.high == 0)
        {
            /* K X
             * ---
             * 0 K
             */
            if ((d.s.low & (d.s.low - 1)) == 0)     /* if d is a power of 2 */
            {
                if (rem)
                    *rem = n.s.low & (d.s.low - 1);
                if (d.s.low == 1)
                    return n.all;
                sr = __builtin_ctzll(d.s.low);
                q.s.high = n.s.high >> sr;
                q.s.low = (n.s.high << (n_udword_bits - sr)) | (n.s.low >> sr);
                return q.all;
            }
            /* K X
             * ---
             * 0 K
             */
            sr = 1 + n_udword_bits + __builtin_clzll(d.s.low)
                                   - __builtin_clzll(n.s.high);
            /* 2 <= sr <= n_utword_bits - 1
             * q.all = n.all << (n_utword_bits - sr);
             * r.all = n.all >> sr;
             */
            if (sr == n_udword_bits)
            {
                q.s.low = 0;
                q.s.high = n.s.low;
                r.s.high = 0;
                r.s.low = n.s.high;
            }
            else if (sr < n_udword_bits)  // 2 <= sr <= n_udword_bits - 1
            {
                q.s.low = 0;
                q.s.high = n.s.low << (n_udword_bits - sr);
                r.s.high = n.s.high >> sr;
                r.s.low = (n.s.high << (n_udword_bits - sr)) | (n.s.low >> sr);
            }
            else              // n_udword_bits + 1 <= sr <= n_utword_bits - 1
            {
                q.s.low = n.s.low << (n_utword_bits - sr);
                q.s.high = (n.s.high << (n_utword_bits - sr)) |
                           (n.s.low >> (sr - n_udword_bits));
                r.s.high = 0;
                r.s.low = n.s.high >> (sr - n_udword_bits);
            }
        }
        else
        {
            /* K X
             * ---
             * K K
             */
            sr = __builtin_clzll(d.s.high) - __builtin_clzll(n.s.high);
            /*0 <= sr <= n_udword_bits - 1 or sr large */
            if (sr > n_udword_bits - 1)
            {
               if (rem)
                    *rem = n.all;
                return 0;
            }
            ++sr;
            /* 1 <= sr <= n_udword_bits
             * q.all = n.all << (n_utword_bits - sr);
             * r.all = n.all >> sr;
             */
            q.s.low = 0;
            if (sr == n_udword_bits)
            {
                q.s.high = n.s.low;
                r.s.high = 0;
                r.s.low = n.s.high;
            }
            else
            {
                r.s.high = n.s.high >> sr;
                r.s.low = (n.s.high << (n_udword_bits - sr)) | (n.s.low >> sr);
                q.s.high = n.s.low << (n_udword_bits - sr);
            }
        }
    }
    /* Not a special case
     * q and r are initialized with:
     * q.all = n.all << (n_utword_bits - sr);
     * r.all = n.all >> sr;
     * 1 <= sr <= n_utword_bits - 1
     */
    su_int carry = 0;
    for (; sr > 0; --sr)
    {
        /* r:q = ((r:q)  << 1) | carry */
        r.s.high = (r.s.high << 1) | (r.s.low  >> (n_udword_bits - 1));
        r.s.low  = (r.s.low  << 1) | (q.s.high >> (n_udword_bits - 1));
        q.s.high = (q.s.high << 1) | (q.s.low  >> (n_udword_bits - 1));
        q.s.low  = (q.s.low  << 1) | carry;
        /* carry = 0;
         * if (r.all >= d.all)
         * {
         *     r.all -= d.all;
         *      carry = 1;
         * }
         */
        const ti_int s = (ti_int)(d.all - r.all - 1) >> (n_utword_bits - 1);
        carry = s & 1;
        r.all -= d.all & s;
    }
    q.all = (q.all << 1) | carry;
    if (rem)
        *rem = r.all;
    return q.all;
}

#endif /* CRT_HAS_128BIT */


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* ===-- udivmodti4.c - Implement __udivmodti4 -----------------------------===
2			*
3			* The LLVM Compiler Infrastructure
4			*
5			* This file is dual licensed under the MIT and the University of Illinois Open
6			* Source Licenses. See LICENSE.TXT for details.
7			*
8			* ===----------------------------------------------------------------------===
9			*
10			* This file implements __udivmodti4 for the compiler_rt library.
11			*
12			* ===----------------------------------------------------------------------===
13			*/
14
15			#include "int_lib.h"
16
17			#ifdef CRT_HAS_128BIT
18
19			/* Effects: if rem != 0, *rem = a % b
20			* Returns: a / b
21			*/
22
23			/* Translated from Figure 3-40 of The PowerPC Compiler Writer's Guide */
24
25			COMPILER_RT_ABI tu_int
26			__udivmodti4(tu_int a, tu_int b, tu_int* rem)
27			{
28			const unsigned n_udword_bits = sizeof(du_int) * CHAR_BIT;
29			const unsigned n_utword_bits = sizeof(tu_int) * CHAR_BIT;
30			utwords n;
31			n.all = a;
32			utwords d;
33			d.all = b;
34			utwords q;
35			utwords r;
36			unsigned sr;
37			/* special cases, X is unknown, K != 0 */
38			if (n.s.high == 0)
39			{
40			if (d.s.high == 0)
41			{
42			/* 0 X
43			* ---
44			* 0 X
45			*/
46			if (rem)
47			*rem = n.s.low % d.s.low;
48			return n.s.low / d.s.low;
49			}
50			/* 0 X
51			* ---
52			* K X
53			*/
54			if (rem)
55			*rem = n.s.low;
56			return 0;
57			}
58			/* n.s.high != 0 */
59			if (d.s.low == 0)
60			{
61			if (d.s.high == 0)
62			{
63			/* K X
64			* ---
65			* 0 0
66			*/
67			if (rem)
68			*rem = n.s.high % d.s.low;
69			return n.s.high / d.s.low;
70			}
71			/* d.s.high != 0 */
72			if (n.s.low == 0)
73			{
74			/* K 0
75			* ---
76			* K 0
77			*/
78			if (rem)
79			{
80			r.s.high = n.s.high % d.s.high;
81			r.s.low = 0;
82			*rem = r.all;
83			}
84			return n.s.high / d.s.high;
85			}
86			/* K K
87			* ---
88			* K 0
89			*/
90			if ((d.s.high & (d.s.high - 1)) == 0) /* if d is a power of 2 */
91			{
92			if (rem)
93			{
94			r.s.low = n.s.low;
95			r.s.high = n.s.high & (d.s.high - 1);
96			*rem = r.all;
97			}
98			return n.s.high >> __builtin_ctzll(d.s.high);
99			}
100			/* K K
101			* ---
102			* K 0
103			*/
104			sr = __builtin_clzll(d.s.high) - __builtin_clzll(n.s.high);
105			/* 0 <= sr <= n_udword_bits - 2 or sr large */
106			if (sr > n_udword_bits - 2)
107			{
108			if (rem)
109			*rem = n.all;
110			return 0;
111			}
112			++sr;
113			/* 1 <= sr <= n_udword_bits - 1 */
114			/* q.all = n.all << (n_utword_bits - sr); */
115			q.s.low = 0;
116			q.s.high = n.s.low << (n_udword_bits - sr);
117			/* r.all = n.all >> sr; */
118			r.s.high = n.s.high >> sr;
119			r.s.low = (n.s.high << (n_udword_bits - sr)) \| (n.s.low >> sr);
120			}
121			else /* d.s.low != 0 */
122			{
123			if (d.s.high == 0)
124			{
125			/* K X
126			* ---
127			* 0 K
128			*/
129			if ((d.s.low & (d.s.low - 1)) == 0) /* if d is a power of 2 */
130			{
131			if (rem)
132			*rem = n.s.low & (d.s.low - 1);
133			if (d.s.low == 1)
134			return n.all;
135			sr = __builtin_ctzll(d.s.low);
136			q.s.high = n.s.high >> sr;
137			q.s.low = (n.s.high << (n_udword_bits - sr)) \| (n.s.low >> sr);
138			return q.all;
139			}
140			/* K X
141			* ---
142			* 0 K
143			*/
144			sr = 1 + n_udword_bits + __builtin_clzll(d.s.low)
145			- __builtin_clzll(n.s.high);
146			/* 2 <= sr <= n_utword_bits - 1
147			* q.all = n.all << (n_utword_bits - sr);
148			* r.all = n.all >> sr;
149			*/
150			if (sr == n_udword_bits)
151			{
152			q.s.low = 0;
153			q.s.high = n.s.low;
154			r.s.high = 0;
155			r.s.low = n.s.high;
156			}
157			else if (sr < n_udword_bits) // 2 <= sr <= n_udword_bits - 1
158			{
159			q.s.low = 0;
160			q.s.high = n.s.low << (n_udword_bits - sr);
161			r.s.high = n.s.high >> sr;
162			r.s.low = (n.s.high << (n_udword_bits - sr)) \| (n.s.low >> sr);
163			}
164			else // n_udword_bits + 1 <= sr <= n_utword_bits - 1
165			{
166			q.s.low = n.s.low << (n_utword_bits - sr);
167			q.s.high = (n.s.high << (n_utword_bits - sr)) \|
168			(n.s.low >> (sr - n_udword_bits));
169			r.s.high = 0;
170			r.s.low = n.s.high >> (sr - n_udword_bits);
171			}
172			}
173			else
174			{
175			/* K X
176			* ---
177			* K K
178			*/
179			sr = __builtin_clzll(d.s.high) - __builtin_clzll(n.s.high);
180			/0 <= sr <= n_udword_bits - 1 or sr large /
181			if (sr > n_udword_bits - 1)
182			{
183			if (rem)
184			*rem = n.all;
185			return 0;
186			}
187			++sr;
188			/* 1 <= sr <= n_udword_bits
189			* q.all = n.all << (n_utword_bits - sr);
190			* r.all = n.all >> sr;
191			*/
192			q.s.low = 0;
193			if (sr == n_udword_bits)
194			{
195			q.s.high = n.s.low;
196			r.s.high = 0;
197			r.s.low = n.s.high;
198			}
199			else
200			{
201			r.s.high = n.s.high >> sr;
202			r.s.low = (n.s.high << (n_udword_bits - sr)) \| (n.s.low >> sr);
203			q.s.high = n.s.low << (n_udword_bits - sr);
204			}
205			}
206			}
207			/* Not a special case
208			* q and r are initialized with:
209			* q.all = n.all << (n_utword_bits - sr);
210			* r.all = n.all >> sr;
211			* 1 <= sr <= n_utword_bits - 1
212			*/
213			su_int carry = 0;
214			for (; sr > 0; --sr)
215			{
216			/* r:q = ((r:q) << 1) \| carry */
217			r.s.high = (r.s.high << 1) \| (r.s.low >> (n_udword_bits - 1));
218			r.s.low = (r.s.low << 1) \| (q.s.high >> (n_udword_bits - 1));
219			q.s.high = (q.s.high << 1) \| (q.s.low >> (n_udword_bits - 1));
220			q.s.low = (q.s.low << 1) \| carry;
221			/* carry = 0;
222			* if (r.all >= d.all)
223			* {
224			* r.all -= d.all;
225			* carry = 1;
226			* }
227			*/
228			const ti_int s = (ti_int)(d.all - r.all - 1) >> (n_utword_bits - 1);
229			carry = s & 1;
230			r.all -= d.all & s;
231			}
232			q.all = (q.all << 1) \| carry;
233			if (rem)
234			*rem = r.all;
235			return q.all;
236			}
237
238			#endif /* CRT_HAS_128BIT */