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Comparing trunk/sys/i386/include/ieeefp.h (file contents):
Revision 5087 by laffer1, Sat Mar 31 17:05:11 2012 UTC vs.
Revision 5088 by laffer1, Fri Aug 3 00:59:05 2012 UTC

#	Line 1 | Line 1
1	<	/* $MidnightBSD$ */
1	>	/* $MidnightBSD: src/sys/i386/include/ieeefp.h,v 1.2 2012/03/31 17:05:09 laffer1 Exp $ */
2		/*-
3	+	* Copyright (c) 2003 Peter Wemm.
4		* Copyright (c) 1990 Andrew Moore, Talke Studio
5		* All rights reserved.
6		*
#	Line 32 | Line 33
33		* SUCH DAMAGE.
34		*
35		*      from: @(#) ieeefp.h     1.0 (Berkeley) 9/23/93
36	<	* $FreeBSD: src/sys/i386/include/ieeefp.h,v 1.11 2005/03/15 15:53:39 das Exp $
36	>	* $FreeBSD$
37		*/
38
38	–	/*
39	–	*      IEEE floating point type and constant definitions.
40	–	*/
41	–
39		#ifndef _MACHINE_IEEEFP_H_
40		#define _MACHINE_IEEEFP_H_
41
42	+	/*
43	+	* IEEE floating point type, constant and function definitions.
44	+	* XXX: FP*FLD and FP*OFF are undocumented pollution.
45	+	*/
46	+
47		#ifndef _SYS_CDEFS_H_
48		#error this file needs sys/cdefs.h as a prerequisite
49		#endif
50
51		/*
52	<	* FP rounding modes
52	>	* Rounding modes.
53		*/
54		typedef enum {
55		FP_RN=0,        /* round to nearest */
56	<	FP_RM,          /* round down to minus infinity */
57	<	FP_RP,          /* round up to plus infinity */
56	>	FP_RM,          /* round down towards minus infinity */
57	>	FP_RP,          /* round up towards plus infinity */
58		FP_RZ           /* truncate */
59		} fp_rnd_t;
60
61		/*
62	<	* FP precision modes
62	>	* Precision (i.e., rounding precision) modes.
63		*/
64		typedef enum {
65		FP_PS=0,        /* 24 bit (single-precision) */
#	Line 69 | Line 71 | typedef enum {
71		#define fp_except_t     int
72
73		/*
74	<	* FP exception masks
74	>	* Exception bit masks.
75		*/
76		#define FP_X_INV        0x01    /* invalid operation */
77		#define FP_X_DNML       0x02    /* denormal */
#	Line 80 | Line 82 | typedef enum {
82		#define FP_X_STK        0x40    /* stack fault */
83
84		/*
85	<	* FP registers
85	>	* FPU control word bit-field masks.
86		*/
87	<	#define FP_MSKS_REG     0       /* exception masks */
88	<	#define FP_PRC_REG      0       /* precision */
89	<	#define FP_RND_REG      0       /* direction */
88	<	#define FP_STKY_REG     1       /* sticky flags */
87	>	#define FP_MSKS_FLD     0x3f    /* exception masks field */
88	>	#define FP_PRC_FLD      0x300   /* precision control field */
89	>	#define FP_RND_FLD      0xc00   /* rounding control field */
90
91		/*
92	<	* FP register bit field masks
92	>	* FPU status word bit-field masks.
93		*/
93	–	#define FP_MSKS_FLD     0x3f    /* exception masks field */
94	–	#define FP_PRC_FLD      0x300   /* precision control field */
95	–	#define FP_RND_FLD      0xc00   /* round control field */
94		#define FP_STKY_FLD     0x3f    /* sticky flags field */
95
96		/*
97	<	* FP register bit field offsets
97	>	* FPU control word bit-field offsets (shift counts).
98		*/
99		#define FP_MSKS_OFF     0       /* exception masks offset */
100		#define FP_PRC_OFF      8       /* precision control offset */
101	<	#define FP_RND_OFF      10      /* round control offset */
101	>	#define FP_RND_OFF      10      /* rounding control offset */
102	>
103	>	/*
104	>	* FPU status word bit-field offsets (shift counts).
105	>	*/
106		#define FP_STKY_OFF     0       /* sticky flags offset */
107
108		#ifdef __GNUCLIKE_ASM
109
110	+	#define __fldcw(addr)   __asm __volatile("fldcw %0" : : "m" (*(addr)))
111		#define __fldenv(addr)  __asm __volatile("fldenv %0" : : "m" (*(addr)))
112	<	#define __fnstenv(addr) __asm __volatile("fnstenv %0" : "=m" (*(addr)))
112	>	#define __fnclex()      __asm __volatile("fnclex")
113		#define __fnstcw(addr)  __asm __volatile("fnstcw %0" : "=m" (*(addr)))
114	+	#define __fnstenv(addr) __asm __volatile("fnstenv %0" : "=m" (*(addr)))
115		#define __fnstsw(addr)  __asm __volatile("fnstsw %0" : "=m" (*(addr)))
116
117		/*
118	<	* return the contents of a FP register
118	>	* Load the control word.  Be careful not to trap if there is a currently
119	>	* unmasked exception (ones that will become freshly unmasked are not a
120	>	* problem).  This case must be handled by a save/restore of the
121	>	* environment or even of the full x87 state.  Accessing the environment
122	>	* is very inefficient, so only do it when necessary.
123		*/
124	<	static __inline__ int
125	<	__fpgetreg(int _reg)
124	>	static __inline void
125	>	__fnldcw(unsigned short _cw, unsigned short _newcw)
126		{
127	<	unsigned short _mem;
127	>	struct {
128	>	unsigned _cw;
129	>	unsigned _other[6];
130	>	} _env;
131	>	unsigned short _sw;
132
133	<	/*-
134	<	* This is more efficient than it looks.  The switch gets optimized
135	<	* away if _reg is constant.
136	<	*
137	<	* The default case only supports _reg == 0.  We could handle more
138	<	* registers (e.g., tags) using fnstenv, but the interface doesn't
139	<	* support more.
140	<	*/
129	<	switch(_reg) {
130	<	default:
131	<	__fnstcw(&_mem);
132	<	break;
133	<	case FP_STKY_REG:
134	<	__fnstsw(&_mem);
135	<	break;
133	>	if ((_cw & FP_MSKS_FLD) != FP_MSKS_FLD) {
134	>	__fnstsw(&_sw);
135	>	if (((_sw & ~_cw) & FP_STKY_FLD) != 0) {
136	>	__fnstenv(&_env);
137	>	_env._cw = _newcw;
138	>	__fldenv(&_env);
139	>	return;
140	>	}
141		}
142	<	return _mem;
142	>	__fldcw(&_newcw);
143		}
144
145	<	/*
146	<	* set a FP mode; return previous mode
142	<	*/
143	<	static __inline__ int
144	<	__fpsetreg(int _m, int _reg, int _fld, int _off)
145	>	static __inline fp_rnd_t
146	>	fpgetround(void)
147		{
148	<	unsigned _env[7];
147	<	unsigned _p;
148	>	unsigned short _cw;
149
150	<	/*
151	<	* _reg == 0 could be handled better using fnstcw/fldcw.
151	<	*/
152	<	__fnstenv(_env);
153	<	_p =  (_env[_reg] & _fld) >> _off;
154	<	_env[_reg] = (_env[_reg] & ~_fld) | (_m << _off & _fld);
155	<	__fldenv(_env);
156	<	return _p;
150	>	__fnstcw(&_cw);
151	>	return ((fp_rnd_t)((_cw & FP_RND_FLD) >> FP_RND_OFF));
152		}
153
154	<	#endif /* __GNUCLIKE_ASM */
154	>	static __inline fp_rnd_t
155	>	fpsetround(fp_rnd_t _m)
156	>	{
157	>	fp_rnd_t _p;
158	>	unsigned short _cw, _newcw;
159
160	+	__fnstcw(&_cw);
161	+	_p = (fp_rnd_t)((_cw & FP_RND_FLD) >> FP_RND_OFF);
162	+	_newcw = _cw & ~FP_RND_FLD;
163	+	_newcw |= (_m << FP_RND_OFF) & FP_RND_FLD;
164	+	__fnldcw(_cw, _newcw);
165	+	return (_p);
166	+	}
167	+
168	+	static __inline fp_prec_t
169	+	fpgetprec(void)
170	+	{
171	+	unsigned short _cw;
172	+
173	+	__fnstcw(&_cw);
174	+	return ((fp_prec_t)((_cw & FP_PRC_FLD) >> FP_PRC_OFF));
175	+	}
176	+
177	+	static __inline fp_prec_t
178	+	fpsetprec(fp_prec_t _m)
179	+	{
180	+	fp_prec_t _p;
181	+	unsigned short _cw, _newcw;
182	+
183	+	__fnstcw(&_cw);
184	+	_p = (fp_prec_t)((_cw & FP_PRC_FLD) >> FP_PRC_OFF);
185	+	_newcw = _cw & ~FP_PRC_FLD;
186	+	_newcw |= (_m << FP_PRC_OFF) & FP_PRC_FLD;
187	+	__fnldcw(_cw, _newcw);
188	+	return (_p);
189	+	}
190	+
191		/*
192	<	* SysV/386 FP control interface
192	>	* Get or set the exception mask.
193	>	* Note that the x87 mask bits are inverted by the API -- a mask bit of 1
194	>	* means disable for x87 and SSE, but for fp*mask() it means enable.
195		*/
196	<	#define fpgetround()    ((fp_rnd_t)                                     \
197	<	((__fpgetreg(FP_RND_REG) & FP_RND_FLD) >> FP_RND_OFF))
198	<	#define fpsetround(m)   ((fp_rnd_t)                                     \
199	<	__fpsetreg((m), FP_RND_REG, FP_RND_FLD, FP_RND_OFF))
200	<	#define fpgetprec()     ((fp_prec_t)                                    \
201	<	((__fpgetreg(FP_PRC_REG) & FP_PRC_FLD) >> FP_PRC_OFF))
202	<	#define fpsetprec(m)    ((fp_prec_t)                                    \
203	<	__fpsetreg((m), FP_PRC_REG, FP_PRC_FLD, FP_PRC_OFF))
204	<	#define fpgetmask()     ((fp_except_t)                                  \
205	<	((~__fpgetreg(FP_MSKS_REG) & FP_MSKS_FLD) >> FP_MSKS_OFF))
206	<	#define fpsetmask(m)    ((fp_except_t)                                  \
207	<	(~__fpsetreg(~(m), FP_MSKS_REG, FP_MSKS_FLD, FP_MSKS_OFF)) &    \
208	<	(FP_MSKS_FLD >> FP_MSKS_OFF))
209	<	#define fpgetsticky()   ((fp_except_t)                                  \
210	<	((__fpgetreg(FP_STKY_REG) & FP_STKY_FLD) >> FP_STKY_OFF))
211	<	#define fpresetsticky(m) ((fp_except_t)                                 \
212	<	__fpsetreg(0, FP_STKY_REG, (m), FP_STKY_OFF))
196	>
197	>	static __inline fp_except_t
198	>	fpgetmask(void)
199	>	{
200	>	unsigned short _cw;
201	>
202	>	__fnstcw(&_cw);
203	>	return ((~_cw & FP_MSKS_FLD) >> FP_MSKS_OFF);
204	>	}
205	>
206	>	static __inline fp_except_t
207	>	fpsetmask(fp_except_t _m)
208	>	{
209	>	fp_except_t _p;
210	>	unsigned short _cw, _newcw;
211	>
212	>	__fnstcw(&_cw);
213	>	_p = (~_cw & FP_MSKS_FLD) >> FP_MSKS_OFF;
214	>	_newcw = _cw & ~FP_MSKS_FLD;
215	>	_newcw |= (~_m << FP_MSKS_OFF) & FP_MSKS_FLD;
216	>	__fnldcw(_cw, _newcw);
217	>	return (_p);
218	>	}
219	>
220	>	static __inline fp_except_t
221	>	fpgetsticky(void)
222	>	{
223	>	unsigned _ex;
224	>	unsigned short _sw;
225	>
226	>	__fnstsw(&_sw);
227	>	_ex = (_sw & FP_STKY_FLD) >> FP_STKY_OFF;
228	>	return ((fp_except_t)_ex);
229	>	}
230	>
231	>	static __inline fp_except_t
232	>	fpresetsticky(fp_except_t _m)
233	>	{
234	>	struct {
235	>	unsigned _cw;
236	>	unsigned _sw;
237	>	unsigned _other[5];
238	>	} _env;
239	>	fp_except_t _p;
240	>
241	>	_m &= FP_STKY_FLD >> FP_STKY_OFF;
242	>	_p = fpgetsticky();
243	>	if ((_p & ~_m) == _p)
244	>	return (_p);
245	>	if ((_p & ~_m) == 0) {
246	>	__fnclex();
247	>	return (_p);
248	>	}
249	>	__fnstenv(&_env);
250	>	_env._sw &= ~_m;
251	>	__fldenv(&_env);
252	>	return (_p);
253	>	}
254	>
255	>	#endif /* __GNUCLIKE_ASM */
256
257		/* Suppress prototypes in the MI header. */
258		#define _IEEEFP_INLINED_        1

Comparing trunk/sys/i386/include/ieeefp.h (property cvs2svn:cvs-rev):
Revision 5087 by laffer1, Sat Mar 31 17:05:11 2012 UTC vs.
Revision 5088 by laffer1, Fri Aug 3 00:59:05 2012 UTC

#	Line 1 | Line 1
1	<	1.2
1	>	1.3

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