1/* Definitions of target machine for GNU compiler, for IBM S/390
2   Copyright (C) 1999-2015 Free Software Foundation, Inc.
3   Contributed by Hartmut Penner (hpenner@de.ibm.com) and
4                  Ulrich Weigand (uweigand@de.ibm.com).
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16for more details.
17
18Under Section 7 of GPL version 3, you are granted additional
19permissions described in the GCC Runtime Library Exception, version
203.1, as published by the Free Software Foundation.
21
22You should have received a copy of the GNU General Public License and
23a copy of the GCC Runtime Library Exception along with this program;
24see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
25<http://www.gnu.org/licenses/>.  */
26
27#ifndef __s390x__
28
29#define EXPD(fp)	   (((fp.l.i[0]) >> 16) & 0x7FFF)
30#define EXPONENT_BIAS	   16383
31#define MANTISSA_BITS      112
32#define PRECISION          (MANTISSA_BITS + 1)
33#define SIGNBIT		   0x80000000
34#define SIGN(fp)	   ((fp.l.i[0]) & SIGNBIT)
35#define MANTD_HIGH_LL(fp)  ((fp.ll[0] & HIGH_LL_FRAC_MASK) | HIGH_LL_UNIT_BIT)
36#define MANTD_LOW_LL(fp)   (fp.ll[1])
37#define FRACD_ZERO_P(fp)   (!fp.ll[1] && !(fp.ll[0] & HIGH_LL_FRAC_MASK))
38#define HIGH_LL_FRAC_BITS  48
39#define HIGH_LL_UNIT_BIT   ((UDItype_x)1 << HIGH_LL_FRAC_BITS)
40#define HIGH_LL_FRAC_MASK  (HIGH_LL_UNIT_BIT - 1)
41#define LLONG_MAX       9223372036854775807LL
42#define LLONG_MIN       (-LLONG_MAX - 1LL)
43
44typedef int DItype_x __attribute__ ((mode (DI)));
45typedef unsigned int UDItype_x __attribute__ ((mode (DI)));
46typedef int SItype_x __attribute__ ((mode (SI)));
47typedef unsigned int USItype_x __attribute__ ((mode (SI)));
48
49union double_long {
50  long double d;
51  struct {
52      SItype_x i[4]; /* 32 bit parts: 0 upper ... 3 lowest */
53    } l;
54  UDItype_x ll[2];   /* 64 bit parts: 0 upper, 1 lower */
55};
56
57static __inline__ void
58fexceptdiv (float d, float e)
59{
60  __asm__ __volatile__ ("debr %0,%1" : : "f" (d), "f" (e) );
61}
62
63DItype_x __fixtfdi (long double a1);
64
65/* convert double to unsigned int */
66DItype_x
67__fixtfdi (long double a1)
68{
69    register union double_long dl1;
70    register int exp;
71    register UDItype_x l;
72
73    dl1.d = a1;
74
75    /* +/- 0, denormalized */
76    if (!EXPD (dl1))
77      return 0;
78
79    /* The exponent - considered the binary point at the right end of
80       the mantissa.  */
81    exp = EXPD (dl1) - EXPONENT_BIAS - MANTISSA_BITS;
82
83    /* number < 1: If the mantissa would need to be right-shifted more bits than
84       its size the result would be zero.  */
85    if (exp <= -PRECISION)
86      return 0;
87
88    /* NaN: All exponent bits set and a nonzero fraction.  */
89    if ((EXPD(dl1) == 0x7fff) && !FRACD_ZERO_P (dl1))
90      {
91	/* C99 Annex F.4 requires an "invalid" exception to be thrown.  */
92	fexceptdiv (0.0, 0.0);
93	return 0x8000000000000000ULL;
94      }
95
96    /* One extra bit is needed for the unit bit which is appended by
97       MANTD_HIGH_LL on the left of the matissa.  */
98    exp += HIGH_LL_FRAC_BITS + 1;
99
100    /* If the result would still need a left shift it will be too large
101       to be represented.  Compared to the unsigned variant we have to
102       take care that there is still space for the sign bit to be
103       applied.  So we can only go on if there is a right-shift by one
104       or more.  */
105    if (exp >= 0)
106      {
107	/* Don't throw an exception for -1p+63  */
108	if (!SIGN (dl1)
109	    || exp > 0
110	    || MANTD_LOW_LL (dl1) >> (HIGH_LL_FRAC_BITS + 1)
111	    || (dl1.ll[0] & HIGH_LL_FRAC_MASK))
112	  /* C99 Annex F.4 requires an "invalid" exception to be thrown.  */
113	  fexceptdiv (0.0, 0.0);
114	return SIGN (dl1) ? LLONG_MIN : LLONG_MAX;
115      }
116
117    l = MANTD_LOW_LL (dl1) >> (HIGH_LL_FRAC_BITS + 1)
118        | MANTD_HIGH_LL (dl1) << (64 - (HIGH_LL_FRAC_BITS + 1));
119
120    return SIGN (dl1) ? -(l >> -exp) : l >> -exp;
121}
122#endif /* !__s390x__ */
123