1/* Decimal context header module for the decNumber C Library.
2   Copyright (C) 2005-2015 Free Software Foundation, Inc.
3   Contributed by IBM Corporation.  Author Mike Cowlishaw.
4
5   This file is part of GCC.
6
7   GCC is free software; you can redistribute it and/or modify it under
8   the terms of the GNU General Public License as published by the Free
9   Software Foundation; either version 3, or (at your option) any later
10   version.
11
12   GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13   WARRANTY; without even the implied warranty of MERCHANTABILITY or
14   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15   for more details.
16
17Under Section 7 of GPL version 3, you are granted additional
18permissions described in the GCC Runtime Library Exception, version
193.1, as published by the Free Software Foundation.
20
21You should have received a copy of the GNU General Public License and
22a copy of the GCC Runtime Library Exception along with this program;
23see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
24<http://www.gnu.org/licenses/>.  */
25
26/* ------------------------------------------------------------------ */
27/* Decimal Context module header				      */
28/* ------------------------------------------------------------------ */
29/*								      */
30/* Context variables must always have valid values:		      */
31/*								      */
32/*  status   -- [any bits may be cleared, but not set, by user]       */
33/*  round    -- must be one of the enumerated rounding modes	      */
34/*								      */
35/* The following variables are implied for fixed size formats (i.e.,  */
36/* they are ignored) but should still be set correctly in case used   */
37/* with decNumber functions:					      */
38/*								      */
39/*  clamp    -- must be either 0 or 1				      */
40/*  digits   -- must be in the range 1 through 999999999	      */
41/*  emax     -- must be in the range 0 through 999999999	      */
42/*  emin     -- must be in the range 0 through -999999999	      */
43/*  extended -- must be either 0 or 1 [present only if DECSUBSET]     */
44/*  traps    -- only defined bits may be set			      */
45/*								      */
46/* ------------------------------------------------------------------ */
47
48#if !defined(DECCONTEXT)
49  #define DECCONTEXT
50  #define DECCNAME     "decContext"			/* Short name */
51  #define DECCFULLNAME "Decimal Context Descriptor"   /* Verbose name */
52  #define DECCAUTHOR   "Mike Cowlishaw" 	      /* Who to blame */
53
54  #include "gstdint.h"		   /* C99 standard integers	      */
55  #include <stdio.h>		   /* for printf, etc.		      */
56  #include <signal.h>		   /* for traps 		      */
57
58  /* Extended flags setting -- set this to 0 to use only IEEE flags   */
59  #if !defined(DECEXTFLAG)
60  #define DECEXTFLAG 1		   /* 1=enable extended flags	      */
61  #endif
62
63  /* Conditional code flag -- set this to 0 for best performance      */
64  #if !defined(DECSUBSET)
65  #define DECSUBSET  0		   /* 1=enable subset arithmetic      */
66  #endif
67
68  /* Context for operations, with associated constants		      */
69  enum rounding {
70    DEC_ROUND_CEILING,		   /* round towards +infinity	      */
71    DEC_ROUND_UP,		   /* round away from 0 	      */
72    DEC_ROUND_HALF_UP,		   /* 0.5 rounds up		      */
73    DEC_ROUND_HALF_EVEN,	   /* 0.5 rounds to nearest even      */
74    DEC_ROUND_HALF_DOWN,	   /* 0.5 rounds down		      */
75    DEC_ROUND_DOWN,		   /* round towards 0 (truncate)      */
76    DEC_ROUND_FLOOR,		   /* round towards -infinity	      */
77    DEC_ROUND_05UP,		   /* round for reround 	      */
78    DEC_ROUND_MAX		   /* enum must be less than this     */
79    };
80  #define DEC_ROUND_DEFAULT DEC_ROUND_HALF_EVEN;
81
82  typedef struct {
83    int32_t  digits;		   /* working precision 	      */
84    int32_t  emax;		   /* maximum positive exponent       */
85    int32_t  emin;		   /* minimum negative exponent       */
86    enum     rounding round;	   /* rounding mode		      */
87    uint32_t traps;		   /* trap-enabler flags	      */
88    uint32_t status;		   /* status flags		      */
89    uint8_t  clamp;		   /* flag: apply IEEE exponent clamp */
90    #if DECSUBSET
91    uint8_t  extended;		   /* flag: special-values allowed    */
92    #endif
93    } decContext;
94
95  /* Maxima and Minima for context settings			      */
96  #define DEC_MAX_DIGITS 999999999
97  #define DEC_MIN_DIGITS	 1
98  #define DEC_MAX_EMAX	 999999999
99  #define DEC_MIN_EMAX		 0
100  #define DEC_MAX_EMIN		 0
101  #define DEC_MIN_EMIN	-999999999
102  #define DEC_MAX_MATH	    999999 /* max emax, etc., for math funcs. */
103
104  /* Classifications for decimal numbers, aligned with 754 (note that */
105  /* 'normal' and 'subnormal' are meaningful only with a decContext   */
106  /* or a fixed size format).					      */
107  enum decClass {
108    DEC_CLASS_SNAN,
109    DEC_CLASS_QNAN,
110    DEC_CLASS_NEG_INF,
111    DEC_CLASS_NEG_NORMAL,
112    DEC_CLASS_NEG_SUBNORMAL,
113    DEC_CLASS_NEG_ZERO,
114    DEC_CLASS_POS_ZERO,
115    DEC_CLASS_POS_SUBNORMAL,
116    DEC_CLASS_POS_NORMAL,
117    DEC_CLASS_POS_INF
118    };
119  /* Strings for the decClasses */
120  #define DEC_ClassString_SN  "sNaN"
121  #define DEC_ClassString_QN  "NaN"
122  #define DEC_ClassString_NI  "-Infinity"
123  #define DEC_ClassString_NN  "-Normal"
124  #define DEC_ClassString_NS  "-Subnormal"
125  #define DEC_ClassString_NZ  "-Zero"
126  #define DEC_ClassString_PZ  "+Zero"
127  #define DEC_ClassString_PS  "+Subnormal"
128  #define DEC_ClassString_PN  "+Normal"
129  #define DEC_ClassString_PI  "+Infinity"
130  #define DEC_ClassString_UN  "Invalid"
131
132  /* Trap-enabler and Status flags (exceptional conditions), and      */
133  /* their names.  The top byte is reserved for internal use	      */
134  #if DECEXTFLAG
135    /* Extended flags */
136    #define DEC_Conversion_syntax    0x00000001
137    #define DEC_Division_by_zero     0x00000002
138    #define DEC_Division_impossible  0x00000004
139    #define DEC_Division_undefined   0x00000008
140    #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails]	*/
141    #define DEC_Inexact 	     0x00000020
142    #define DEC_Invalid_context      0x00000040
143    #define DEC_Invalid_operation    0x00000080
144    #if DECSUBSET
145    #define DEC_Lost_digits	     0x00000100
146    #endif
147    #define DEC_Overflow	     0x00000200
148    #define DEC_Clamped 	     0x00000400
149    #define DEC_Rounded 	     0x00000800
150    #define DEC_Subnormal	     0x00001000
151    #define DEC_Underflow	     0x00002000
152  #else
153    /* IEEE flags only */
154    #define DEC_Conversion_syntax    0x00000010
155    #define DEC_Division_by_zero     0x00000002
156    #define DEC_Division_impossible  0x00000010
157    #define DEC_Division_undefined   0x00000010
158    #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails]	*/
159    #define DEC_Inexact 	     0x00000001
160    #define DEC_Invalid_context      0x00000010
161    #define DEC_Invalid_operation    0x00000010
162    #if DECSUBSET
163    #define DEC_Lost_digits	     0x00000000
164    #endif
165    #define DEC_Overflow	     0x00000008
166    #define DEC_Clamped 	     0x00000000
167    #define DEC_Rounded 	     0x00000000
168    #define DEC_Subnormal	     0x00000000
169    #define DEC_Underflow	     0x00000004
170  #endif
171
172  /* IEEE 754 groupings for the flags				      */
173  /* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal    */
174  /* are not in IEEE 754]					      */
175  #define DEC_IEEE_754_Division_by_zero  (DEC_Division_by_zero)
176  #if DECSUBSET
177  #define DEC_IEEE_754_Inexact		 (DEC_Inexact | DEC_Lost_digits)
178  #else
179  #define DEC_IEEE_754_Inexact		 (DEC_Inexact)
180  #endif
181  #define DEC_IEEE_754_Invalid_operation (DEC_Conversion_syntax |     \
182					  DEC_Division_impossible |   \
183					  DEC_Division_undefined |    \
184					  DEC_Insufficient_storage |  \
185					  DEC_Invalid_context |       \
186					  DEC_Invalid_operation)
187  #define DEC_IEEE_754_Overflow 	 (DEC_Overflow)
188  #define DEC_IEEE_754_Underflow	 (DEC_Underflow)
189
190  /* flags which are normally errors (result is qNaN, infinite, or 0) */
191  #define DEC_Errors (DEC_IEEE_754_Division_by_zero |		      \
192		      DEC_IEEE_754_Invalid_operation |		      \
193		      DEC_IEEE_754_Overflow | DEC_IEEE_754_Underflow)
194  /* flags which cause a result to become qNaN			      */
195  #define DEC_NaNs    DEC_IEEE_754_Invalid_operation
196
197  /* flags which are normally for information only (finite results)   */
198  #if DECSUBSET
199  #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact    \
200			  | DEC_Lost_digits)
201  #else
202  #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact)
203  #endif
204
205  /* IEEE 854 names (for compatibility with older decNumber versions) */
206  #define DEC_IEEE_854_Division_by_zero  DEC_IEEE_754_Division_by_zero
207  #define DEC_IEEE_854_Inexact		 DEC_IEEE_754_Inexact
208  #define DEC_IEEE_854_Invalid_operation DEC_IEEE_754_Invalid_operation
209  #define DEC_IEEE_854_Overflow 	 DEC_IEEE_754_Overflow
210  #define DEC_IEEE_854_Underflow	 DEC_IEEE_754_Underflow
211
212  /* Name strings for the exceptional conditions		      */
213  #define DEC_Condition_CS "Conversion syntax"
214  #define DEC_Condition_DZ "Division by zero"
215  #define DEC_Condition_DI "Division impossible"
216  #define DEC_Condition_DU "Division undefined"
217  #define DEC_Condition_IE "Inexact"
218  #define DEC_Condition_IS "Insufficient storage"
219  #define DEC_Condition_IC "Invalid context"
220  #define DEC_Condition_IO "Invalid operation"
221  #if DECSUBSET
222  #define DEC_Condition_LD "Lost digits"
223  #endif
224  #define DEC_Condition_OV "Overflow"
225  #define DEC_Condition_PA "Clamped"
226  #define DEC_Condition_RO "Rounded"
227  #define DEC_Condition_SU "Subnormal"
228  #define DEC_Condition_UN "Underflow"
229  #define DEC_Condition_ZE "No status"
230  #define DEC_Condition_MU "Multiple status"
231  #define DEC_Condition_Length 21  /* length of the longest string,   */
232				   /* including terminator	      */
233
234  /* Initialization descriptors, used by decContextDefault	      */
235  #define DEC_INIT_BASE 	0
236  #define DEC_INIT_DECIMAL32   32
237  #define DEC_INIT_DECIMAL64   64
238  #define DEC_INIT_DECIMAL128 128
239  /* Synonyms */
240  #define DEC_INIT_DECSINGLE  DEC_INIT_DECIMAL32
241  #define DEC_INIT_DECDOUBLE  DEC_INIT_DECIMAL64
242  #define DEC_INIT_DECQUAD    DEC_INIT_DECIMAL128
243
244  /* decContext routines					      */
245
246  #include "decContextSymbols.h"
247
248  #ifdef __cplusplus
249  extern "C" {
250  #endif
251
252  extern decContext  * decContextClearStatus(decContext *, uint32_t);
253  extern decContext  * decContextDefault(decContext *, int32_t);
254  extern enum rounding decContextGetRounding(decContext *);
255  extern uint32_t      decContextGetStatus(decContext *);
256  extern decContext  * decContextRestoreStatus(decContext *, uint32_t, uint32_t);
257  extern uint32_t      decContextSaveStatus(decContext *, uint32_t);
258  extern decContext  * decContextSetRounding(decContext *, enum rounding);
259  extern decContext  * decContextSetStatus(decContext *, uint32_t);
260  extern decContext  * decContextSetStatusFromString(decContext *, const char *);
261  extern decContext  * decContextSetStatusFromStringQuiet(decContext *, const char *);
262  extern decContext  * decContextSetStatusQuiet(decContext *, uint32_t);
263  extern const char  * decContextStatusToString(const decContext *);
264  extern int32_t       decContextTestEndian(uint8_t);
265  extern uint32_t      decContextTestSavedStatus(uint32_t, uint32_t);
266  extern uint32_t      decContextTestStatus(decContext *, uint32_t);
267  extern decContext  * decContextZeroStatus(decContext *);
268
269  #ifdef __cplusplus
270  }
271  #endif
272
273#endif
274