xref: /linux/arch/parisc/math-emu/sgl_float.h (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Linux/PA-RISC Project (http://www.parisc-linux.org/)
4  *
5  * Floating-point emulation code
6  *  Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
7  */
8 
9 #ifdef __NO_PA_HDRS
10     PA header file -- do not include this header file for non-PA builds.
11 #endif
12 
13 /* 32-bit word grabbing functions */
14 #define Sgl_firstword(value) Sall(value)
15 #define Sgl_secondword(value) dummy_location
16 #define Sgl_thirdword(value) dummy_location
17 #define Sgl_fourthword(value) dummy_location
18 
19 #define Sgl_sign(object) Ssign(object)
20 #define Sgl_exponent(object) Sexponent(object)
21 #define Sgl_signexponent(object) Ssignexponent(object)
22 #define Sgl_mantissa(object) Smantissa(object)
23 #define Sgl_exponentmantissa(object) Sexponentmantissa(object)
24 #define Sgl_all(object) Sall(object)
25 
26 /* sgl_and_signs ANDs the sign bits of each argument and puts the result
27  * into the first argument. sgl_or_signs ors those same sign bits */
28 #define Sgl_and_signs( src1dst, src2)		\
29     Sall(src1dst) = (Sall(src2)|~((unsigned int)1<<31)) & Sall(src1dst)
30 #define Sgl_or_signs( src1dst, src2)		\
31     Sall(src1dst) = (Sall(src2)&((unsigned int)1<<31)) | Sall(src1dst)
32 
33 /* The hidden bit is always the low bit of the exponent */
34 #define Sgl_clear_exponent_set_hidden(srcdst) Deposit_sexponent(srcdst,1)
35 #define Sgl_clear_signexponent_set_hidden(srcdst) \
36     Deposit_ssignexponent(srcdst,1)
37 #define Sgl_clear_sign(srcdst) Sall(srcdst) &= ~((unsigned int)1<<31)
38 #define Sgl_clear_signexponent(srcdst) Sall(srcdst) &= 0x007fffff
39 
40 /* varamount must be less than 32 for the next three functions */
41 #define Sgl_rightshift(srcdst, varamount)	\
42     Sall(srcdst) >>= varamount
43 #define Sgl_leftshift(srcdst, varamount)	\
44     Sall(srcdst) <<= varamount
45 #define Sgl_rightshift_exponentmantissa(srcdst, varamount) \
46     Sall(srcdst) = \
47 	(Sexponentmantissa(srcdst) >> varamount) | \
48 	(Sall(srcdst) & ((unsigned int)1<<31))
49 
50 #define Sgl_leftshiftby1_withextent(left,right,result) \
51     Shiftdouble(Sall(left),Extall(right),31,Sall(result))
52 
53 #define Sgl_rightshiftby1_withextent(left,right,dst)		\
54     Shiftdouble(Sall(left),Extall(right),1,Extall(right))
55 #define Sgl_arithrightshiftby1(srcdst)	\
56     Sall(srcdst) = (int)Sall(srcdst) >> 1
57 
58 /* Sign extend the sign bit with an integer destination */
59 #define Sgl_signextendedsign(value) Ssignedsign(value)
60 
61 #define Sgl_isone_hidden(sgl_value) (Shidden(sgl_value))
62 #define Sgl_increment(sgl_value) Sall(sgl_value) += 1
63 #define Sgl_increment_mantissa(sgl_value) \
64     Deposit_smantissa(sgl_value,sgl_value+1)
65 #define Sgl_decrement(sgl_value) Sall(sgl_value) -= 1
66 
67 #define Sgl_isone_sign(sgl_value) (Is_ssign(sgl_value)!=0)
68 #define Sgl_isone_hiddenoverflow(sgl_value) \
69     (Is_shiddenoverflow(sgl_value)!=0)
70 #define Sgl_isone_lowmantissa(sgl_value) (Is_slow(sgl_value)!=0)
71 #define Sgl_isone_signaling(sgl_value) (Is_ssignaling(sgl_value)!=0)
72 #define Sgl_is_signalingnan(sgl_value) (Ssignalingnan(sgl_value)==0x1ff)
73 #define Sgl_isnotzero(sgl_value) (Sall(sgl_value)!=0)
74 #define Sgl_isnotzero_hiddenhigh7mantissa(sgl_value) \
75     (Shiddenhigh7mantissa(sgl_value)!=0)
76 #define Sgl_isnotzero_low4(sgl_value) (Slow4(sgl_value)!=0)
77 #define Sgl_isnotzero_exponent(sgl_value) (Sexponent(sgl_value)!=0)
78 #define Sgl_isnotzero_mantissa(sgl_value) (Smantissa(sgl_value)!=0)
79 #define Sgl_isnotzero_exponentmantissa(sgl_value) \
80     (Sexponentmantissa(sgl_value)!=0)
81 #define Sgl_iszero(sgl_value) (Sall(sgl_value)==0)
82 #define Sgl_iszero_signaling(sgl_value) (Is_ssignaling(sgl_value)==0)
83 #define Sgl_iszero_hidden(sgl_value) (Is_shidden(sgl_value)==0)
84 #define Sgl_iszero_hiddenoverflow(sgl_value) \
85     (Is_shiddenoverflow(sgl_value)==0)
86 #define Sgl_iszero_hiddenhigh3mantissa(sgl_value) \
87     (Shiddenhigh3mantissa(sgl_value)==0)
88 #define Sgl_iszero_hiddenhigh7mantissa(sgl_value) \
89     (Shiddenhigh7mantissa(sgl_value)==0)
90 #define Sgl_iszero_sign(sgl_value) (Is_ssign(sgl_value)==0)
91 #define Sgl_iszero_exponent(sgl_value) (Sexponent(sgl_value)==0)
92 #define Sgl_iszero_mantissa(sgl_value) (Smantissa(sgl_value)==0)
93 #define Sgl_iszero_exponentmantissa(sgl_value) \
94     (Sexponentmantissa(sgl_value)==0)
95 #define Sgl_isinfinity_exponent(sgl_value) 		\
96     (Sgl_exponent(sgl_value)==SGL_INFINITY_EXPONENT)
97 #define Sgl_isnotinfinity_exponent(sgl_value) 		\
98     (Sgl_exponent(sgl_value)!=SGL_INFINITY_EXPONENT)
99 #define Sgl_isinfinity(sgl_value)			\
100     (Sgl_exponent(sgl_value)==SGL_INFINITY_EXPONENT &&	\
101     Sgl_mantissa(sgl_value)==0)
102 #define Sgl_isnan(sgl_value)				\
103     (Sgl_exponent(sgl_value)==SGL_INFINITY_EXPONENT &&	\
104     Sgl_mantissa(sgl_value)!=0)
105 #define Sgl_isnotnan(sgl_value)				\
106     (Sgl_exponent(sgl_value)!=SGL_INFINITY_EXPONENT ||	\
107     Sgl_mantissa(sgl_value)==0)
108 #define Sgl_islessthan(sgl_op1,sgl_op2)			\
109     (Sall(sgl_op1) < Sall(sgl_op2))
110 #define Sgl_isgreaterthan(sgl_op1,sgl_op2)		\
111     (Sall(sgl_op1) > Sall(sgl_op2))
112 #define Sgl_isnotlessthan(sgl_op1,sgl_op2)		\
113     (Sall(sgl_op1) >= Sall(sgl_op2))
114 #define Sgl_isequal(sgl_op1,sgl_op2)			\
115     (Sall(sgl_op1) == Sall(sgl_op2))
116 
117 #define Sgl_leftshiftby8(sgl_value) \
118     Sall(sgl_value) <<= 8
119 #define Sgl_leftshiftby4(sgl_value) \
120     Sall(sgl_value) <<= 4
121 #define Sgl_leftshiftby3(sgl_value) \
122     Sall(sgl_value) <<= 3
123 #define Sgl_leftshiftby2(sgl_value) \
124     Sall(sgl_value) <<= 2
125 #define Sgl_leftshiftby1(sgl_value) \
126     Sall(sgl_value) <<= 1
127 #define Sgl_rightshiftby1(sgl_value) \
128     Sall(sgl_value) >>= 1
129 #define Sgl_rightshiftby4(sgl_value) \
130     Sall(sgl_value) >>= 4
131 #define Sgl_rightshiftby8(sgl_value) \
132     Sall(sgl_value) >>= 8
133 
134 #define Sgl_ismagnitudeless(signlessleft,signlessright)			\
135 /*  unsigned int signlessleft, signlessright; */			\
136       (signlessleft < signlessright)
137 
138 
139 #define Sgl_copytoint_exponentmantissa(source,dest)     \
140     dest = Sexponentmantissa(source)
141 
142 /* A quiet NaN has the high mantissa bit clear and at least on other (in this
143  * case the adjacent bit) bit set. */
144 #define Sgl_set_quiet(sgl_value) Deposit_shigh2mantissa(sgl_value,1)
145 #define Sgl_set_exponent(sgl_value,exp) Deposit_sexponent(sgl_value,exp)
146 
147 #define Sgl_set_mantissa(dest,value) Deposit_smantissa(dest,value)
148 #define Sgl_set_exponentmantissa(dest,value) \
149     Deposit_sexponentmantissa(dest,value)
150 
151 /*  An infinity is represented with the max exponent and a zero mantissa */
152 #define Sgl_setinfinity_exponent(sgl_value) \
153     Deposit_sexponent(sgl_value,SGL_INFINITY_EXPONENT)
154 #define Sgl_setinfinity_exponentmantissa(sgl_value)	\
155     Deposit_sexponentmantissa(sgl_value, \
156 	(SGL_INFINITY_EXPONENT << (32-(1+SGL_EXP_LENGTH))))
157 #define Sgl_setinfinitypositive(sgl_value)		\
158     Sall(sgl_value) = (SGL_INFINITY_EXPONENT << (32-(1+SGL_EXP_LENGTH)))
159 #define Sgl_setinfinitynegative(sgl_value)		\
160     Sall(sgl_value) = (SGL_INFINITY_EXPONENT << (32-(1+SGL_EXP_LENGTH))) \
161     | ((unsigned int)1<<31)
162 #define Sgl_setinfinity(sgl_value,sign)					\
163     Sall(sgl_value) = (SGL_INFINITY_EXPONENT << (32-(1+SGL_EXP_LENGTH))) | \
164      ((unsigned int)sign << 31)
165 #define Sgl_sethigh4bits(sgl_value, extsign)  \
166     Deposit_shigh4(sgl_value,extsign)
167 #define Sgl_set_sign(sgl_value,sign) Deposit_ssign(sgl_value,sign)
168 #define Sgl_invert_sign(sgl_value)  \
169     Deposit_ssign(sgl_value,~Ssign(sgl_value))
170 #define Sgl_setone_sign(sgl_value) Deposit_ssign(sgl_value,1)
171 #define Sgl_setone_lowmantissa(sgl_value) Deposit_slow(sgl_value,1)
172 #define Sgl_setzero_sign(sgl_value)  Sall(sgl_value) &= 0x7fffffff
173 #define Sgl_setzero_exponent(sgl_value) Sall(sgl_value) &= 0x807fffff
174 #define Sgl_setzero_mantissa(sgl_value) Sall(sgl_value) &= 0xff800000
175 #define Sgl_setzero_exponentmantissa(sgl_value)  Sall(sgl_value) &= 0x80000000
176 #define Sgl_setzero(sgl_value) Sall(sgl_value) = 0
177 #define Sgl_setnegativezero(sgl_value) Sall(sgl_value) = (unsigned int)1 << 31
178 
179 /* Use following macro for both overflow & underflow conditions */
180 #define ovfl -
181 #define unfl +
182 #define Sgl_setwrapped_exponent(sgl_value,exponent,op) \
183     Deposit_sexponent(sgl_value,(exponent op SGL_WRAP))
184 
185 #define Sgl_setlargestpositive(sgl_value) 				\
186     Sall(sgl_value) = ((SGL_EMAX+SGL_BIAS) << (32-(1+SGL_EXP_LENGTH)))	\
187                       | ((1<<(32-(1+SGL_EXP_LENGTH))) - 1 )
188 #define Sgl_setlargestnegative(sgl_value)				\
189     Sall(sgl_value) = ((SGL_EMAX+SGL_BIAS) << (32-(1+SGL_EXP_LENGTH)))	\
190                       | ((1<<(32-(1+SGL_EXP_LENGTH))) - 1 )		\
191 		      | ((unsigned int)1<<31)
192 
193 #define Sgl_setnegativeinfinity(sgl_value)	\
194     Sall(sgl_value) = 				\
195     ((1<<SGL_EXP_LENGTH) | SGL_INFINITY_EXPONENT) << (32-(1+SGL_EXP_LENGTH))
196 #define Sgl_setlargest(sgl_value,sign) 					\
197     Sall(sgl_value) = (unsigned int)sign << 31 |			\
198         (((SGL_EMAX+SGL_BIAS) << (32-(1+SGL_EXP_LENGTH)))		\
199 	  | ((1 << (32-(1+SGL_EXP_LENGTH))) - 1 ))
200 #define Sgl_setlargest_exponentmantissa(sgl_value)			\
201     Sall(sgl_value) = Sall(sgl_value) & ((unsigned int)1<<31) |		\
202         (((SGL_EMAX+SGL_BIAS) << (32-(1+SGL_EXP_LENGTH)))		\
203 	  | ((1 << (32-(1+SGL_EXP_LENGTH))) - 1 ))
204 
205 /* The high bit is always zero so arithmetic or logical shifts will work. */
206 #define Sgl_right_align(srcdst,shift,extent)				\
207     /* sgl_floating_point srcdst; int shift; extension extent */	\
208     if (shift < 32) {							\
209 	Extall(extent) = Sall(srcdst) << (32-(shift));			\
210     	Sall(srcdst) >>= shift;						\
211     }									\
212     else {								\
213 	Extall(extent) = Sall(srcdst);					\
214 	Sall(srcdst) = 0;						\
215     }
216 #define Sgl_hiddenhigh3mantissa(sgl_value) Shiddenhigh3mantissa(sgl_value)
217 #define Sgl_hidden(sgl_value) Shidden(sgl_value)
218 #define Sgl_lowmantissa(sgl_value) Slow(sgl_value)
219 
220 /* The left argument is never smaller than the right argument */
221 #define Sgl_subtract(sgl_left,sgl_right,sgl_result) \
222     Sall(sgl_result) = Sall(sgl_left) - Sall(sgl_right)
223 
224 /* Subtract right augmented with extension from left augmented with zeros and
225  * store into result and extension. */
226 #define Sgl_subtract_withextension(left,right,extent,result)		\
227     /* sgl_floating_point left,right,result; extension extent */	\
228   Sgl_subtract(left,right,result);					\
229   if((Extall(extent) = 0-Extall(extent)))				\
230       Sall(result) = Sall(result)-1
231 
232 #define Sgl_addition(sgl_left,sgl_right,sgl_result) \
233     Sall(sgl_result) = Sall(sgl_left) + Sall(sgl_right)
234 
235 #define Sgl_xortointp1(left,right,result)			\
236     result = Sall(left) XOR Sall(right);
237 
238 #define Sgl_xorfromintp1(left,right,result)			\
239     Sall(result) = left XOR Sall(right)
240 
241 /* Need to Initialize */
242 #define Sgl_makequietnan(dest)						\
243     Sall(dest) = ((SGL_EMAX+SGL_BIAS)+1)<< (32-(1+SGL_EXP_LENGTH))	\
244                  | (1<<(32-(1+SGL_EXP_LENGTH+2)))
245 #define Sgl_makesignalingnan(dest)					\
246     Sall(dest) = ((SGL_EMAX+SGL_BIAS)+1)<< (32-(1+SGL_EXP_LENGTH))	\
247                  | (1<<(32-(1+SGL_EXP_LENGTH+1)))
248 
249 #define Sgl_normalize(sgl_opnd,exponent)			\
250 	while(Sgl_iszero_hiddenhigh7mantissa(sgl_opnd)) {	\
251 		Sgl_leftshiftby8(sgl_opnd);			\
252 		exponent -= 8;					\
253 	}							\
254 	if(Sgl_iszero_hiddenhigh3mantissa(sgl_opnd)) {		\
255 		Sgl_leftshiftby4(sgl_opnd);			\
256 		exponent -= 4;					\
257 	}							\
258 	while(Sgl_iszero_hidden(sgl_opnd)) {			\
259 		Sgl_leftshiftby1(sgl_opnd);			\
260 		exponent -= 1;					\
261 	}
262 
263 #define Sgl_setoverflow(sgl_opnd)				\
264 	/* set result to infinity or largest number */		\
265 	switch (Rounding_mode()) {				\
266 		case ROUNDPLUS:					\
267 			if (Sgl_isone_sign(sgl_opnd)) {		\
268 				Sgl_setlargestnegative(sgl_opnd); \
269 			}					\
270 			else {					\
271 				Sgl_setinfinitypositive(sgl_opnd); \
272 			}					\
273 			break;					\
274 		case ROUNDMINUS:				\
275 			if (Sgl_iszero_sign(sgl_opnd)) {	\
276 				Sgl_setlargestpositive(sgl_opnd); \
277 			}					\
278 			else {					\
279 				Sgl_setinfinitynegative(sgl_opnd); \
280 			}					\
281 			break;					\
282 		case ROUNDNEAREST:				\
283 			Sgl_setinfinity_exponentmantissa(sgl_opnd); \
284 			break;					\
285 		case ROUNDZERO:					\
286 			Sgl_setlargest_exponentmantissa(sgl_opnd); \
287 	}
288 
289 #define Sgl_denormalize(opnd,exponent,guard,sticky,inexact)		\
290 	Sgl_clear_signexponent_set_hidden(opnd);			\
291 	if (exponent >= (1 - SGL_P)) {					\
292 		guard = (Sall(opnd) >> -exponent) & 1;			\
293 		if (exponent < 0) sticky |= Sall(opnd) << (32+exponent); \
294 		inexact = guard | sticky;				\
295 		Sall(opnd) >>= (1-exponent);				\
296 	}								\
297 	else {								\
298 		guard = 0;						\
299 		sticky |= Sall(opnd);					\
300 		inexact = sticky;					\
301 		Sgl_setzero(opnd);					\
302 	}
303 
304 /*
305  * The fused multiply add instructions requires a single extended format,
306  * with 48 bits of mantissa.
307  */
308 #define SGLEXT_THRESHOLD 48
309 
310 #define Sglext_setzero(valA,valB)	\
311     Sextallp1(valA) = 0; Sextallp2(valB) = 0
312 
313 #define Sglext_isnotzero_mantissap2(valB) (Sextallp2(valB)!=0)
314 #define Sglext_isone_lowp1(val) (Sextlowp1(val)!=0)
315 #define Sglext_isone_highp2(val) (Sexthighp2(val)!=0)
316 #define Sglext_isnotzero_low31p2(val) (Sextlow31p2(val)!=0)
317 #define Sglext_iszero(valA,valB) (Sextallp1(valA)==0 && Sextallp2(valB)==0)
318 
319 #define Sgl_copytoptr(src,destptr) *destptr = src
320 #define Sgl_copyfromptr(srcptr,dest) dest = *srcptr
321 #define Sglext_copy(srca,srcb,desta,destb) \
322     Sextallp1(desta) = Sextallp1(srca);	\
323     Sextallp2(destb) = Sextallp2(srcb)
324 #define Sgl_copyto_sglext(src1,dest1,dest2) \
325 	Sextallp1(dest1) = Sall(src1); Sextallp2(dest2) = 0
326 
327 #define Sglext_swap_lower(leftp2,rightp2)  \
328     Sextallp2(leftp2)  = Sextallp2(leftp2) XOR Sextallp2(rightp2);  \
329     Sextallp2(rightp2) = Sextallp2(leftp2) XOR Sextallp2(rightp2);  \
330     Sextallp2(leftp2)  = Sextallp2(leftp2) XOR Sextallp2(rightp2)
331 
332 #define Sglext_setone_lowmantissap2(value) Deposit_dlowp2(value,1)
333 
334 /* The high bit is always zero so arithmetic or logical shifts will work. */
335 #define Sglext_right_align(srcdstA,srcdstB,shift) \
336   {int shiftamt, sticky;						\
337     shiftamt = shift % 32;						\
338     sticky = 0;								\
339     switch (shift/32) {							\
340      case 0: if (shiftamt > 0) {					\
341 	        sticky = Sextallp2(srcdstB) << 32 - (shiftamt);		\
342                 Variable_shift_double(Sextallp1(srcdstA),		\
343 		 Sextallp2(srcdstB),shiftamt,Sextallp2(srcdstB));	\
344 	        Sextallp1(srcdstA) >>= shiftamt;			\
345 	     }								\
346 	     break;							\
347      case 1: if (shiftamt > 0) {					\
348 	        sticky = (Sextallp1(srcdstA) << 32 - (shiftamt)) |	\
349 			 Sextallp2(srcdstB);				\
350 	     }								\
351 	     else {							\
352 		sticky = Sextallp2(srcdstB);				\
353 	     }								\
354 	     Sextallp2(srcdstB) = Sextallp1(srcdstA) >> shiftamt;	\
355 	     Sextallp1(srcdstA) = 0;					\
356 	     break;							\
357     }									\
358     if (sticky) Sglext_setone_lowmantissap2(srcdstB);			\
359   }
360 
361 /* The left argument is never smaller than the right argument */
362 #define Sglext_subtract(lefta,leftb,righta,rightb,resulta,resultb) \
363     if( Sextallp2(rightb) > Sextallp2(leftb) ) Sextallp1(lefta)--; \
364     Sextallp2(resultb) = Sextallp2(leftb) - Sextallp2(rightb);	\
365     Sextallp1(resulta) = Sextallp1(lefta) - Sextallp1(righta)
366 
367 #define Sglext_addition(lefta,leftb,righta,rightb,resulta,resultb) \
368     /* If the sum of the low words is less than either source, then \
369      * an overflow into the next word occurred. */ \
370     if ((Sextallp2(resultb) = Sextallp2(leftb)+Sextallp2(rightb)) < \
371         Sextallp2(rightb)) \
372 	    Sextallp1(resulta) = Sextallp1(lefta)+Sextallp1(righta)+1; \
373     else Sextallp1(resulta) = Sextallp1(lefta)+Sextallp1(righta)
374 
375 
376 #define Sglext_arithrightshiftby1(srcdstA,srcdstB)	\
377     Shiftdouble(Sextallp1(srcdstA),Sextallp2(srcdstB),1,Sextallp2(srcdstB)); \
378     Sextallp1(srcdstA) = (int)Sextallp1(srcdstA) >> 1
379 
380 #define Sglext_leftshiftby8(valA,valB) \
381     Shiftdouble(Sextallp1(valA),Sextallp2(valB),24,Sextallp1(valA)); \
382     Sextallp2(valB) <<= 8
383 #define Sglext_leftshiftby4(valA,valB) \
384     Shiftdouble(Sextallp1(valA),Sextallp2(valB),28,Sextallp1(valA)); \
385     Sextallp2(valB) <<= 4
386 #define Sglext_leftshiftby3(valA,valB) \
387     Shiftdouble(Sextallp1(valA),Sextallp2(valB),29,Sextallp1(valA)); \
388     Sextallp2(valB) <<= 3
389 #define Sglext_leftshiftby2(valA,valB) \
390     Shiftdouble(Sextallp1(valA),Sextallp2(valB),30,Sextallp1(valA)); \
391     Sextallp2(valB) <<= 2
392 #define Sglext_leftshiftby1(valA,valB) \
393     Shiftdouble(Sextallp1(valA),Sextallp2(valB),31,Sextallp1(valA)); \
394     Sextallp2(valB) <<= 1
395 
396 #define Sglext_rightshiftby4(valueA,valueB) \
397     Shiftdouble(Sextallp1(valueA),Sextallp2(valueB),4,Sextallp2(valueB)); \
398     Sextallp1(valueA) >>= 4
399 #define Sglext_rightshiftby3(valueA,valueB) \
400     Shiftdouble(Sextallp1(valueA),Sextallp2(valueB),3,Sextallp2(valueB)); \
401     Sextallp1(valueA) >>= 3
402 #define Sglext_rightshiftby1(valueA,valueB) \
403     Shiftdouble(Sextallp1(valueA),Sextallp2(valueB),1,Sextallp2(valueB)); \
404     Sextallp1(valueA) >>= 1
405 
406 #define Sglext_xortointp1(left,right,result) Sgl_xortointp1(left,right,result)
407 #define Sglext_xorfromintp1(left,right,result) \
408 	Sgl_xorfromintp1(left,right,result)
409 #define Sglext_copytoint_exponentmantissa(src,dest) \
410 	Sgl_copytoint_exponentmantissa(src,dest)
411 #define Sglext_ismagnitudeless(signlessleft,signlessright) \
412 	Sgl_ismagnitudeless(signlessleft,signlessright)
413 
414 #define Sglext_set_sign(dbl_value,sign)  Sgl_set_sign(dbl_value,sign)
415 #define Sglext_clear_signexponent_set_hidden(srcdst) \
416 	Sgl_clear_signexponent_set_hidden(srcdst)
417 #define Sglext_clear_signexponent(srcdst) Sgl_clear_signexponent(srcdst)
418 #define Sglext_clear_sign(srcdst) Sgl_clear_sign(srcdst)
419 #define Sglext_isone_hidden(dbl_value) Sgl_isone_hidden(dbl_value)
420 
421 #define Sglext_denormalize(opndp1,opndp2,exponent,is_tiny)		\
422   {int sticky;								\
423     is_tiny = TRUE;							\
424     if (exponent == 0 && Sextallp2(opndp2)) {				\
425 	switch (Rounding_mode()) {					\
426 	case ROUNDPLUS:							\
427 		if (Sgl_iszero_sign(opndp1))				\
428 			if (Sgl_isone_hiddenoverflow(opndp1 + 1))	\
429 				is_tiny = FALSE;			\
430 		break;							\
431 	case ROUNDMINUS:						\
432 		if (Sgl_isone_sign(opndp1)) {				\
433 			if (Sgl_isone_hiddenoverflow(opndp1 + 1))	\
434 				is_tiny = FALSE;			\
435 		}							\
436 		break;							\
437 	case ROUNDNEAREST:						\
438 		if (Sglext_isone_highp2(opndp2) &&			\
439 		    (Sglext_isone_lowp1(opndp1) || 			\
440 		     Sglext_isnotzero_low31p2(opndp2)))			\
441 			if (Sgl_isone_hiddenoverflow(opndp1 + 1))	\
442 				is_tiny = FALSE;			\
443 		break;							\
444 	}								\
445     }									\
446     Sglext_clear_signexponent_set_hidden(opndp1);			\
447     if (exponent >= (1-DBL_P)) {					\
448 	if (exponent >= -31) {						\
449 	    if (exponent > -31) {					\
450 		sticky = Sextallp2(opndp2) << 31+exponent;		\
451 		Variable_shift_double(opndp1,opndp2,1-exponent,opndp2);	\
452 		Sextallp1(opndp1) >>= 1-exponent;			\
453 	    }								\
454 	    else {							\
455 		sticky = Sextallp2(opndp2);				\
456 		Sextallp2(opndp2) = Sextallp1(opndp1);			\
457 		Sextallp1(opndp1) = 0;					\
458 	    }								\
459 	}								\
460 	else {								\
461 	    sticky = (Sextallp1(opndp1) << 31+exponent) | 		\
462 		     Sextallp2(opndp2);					\
463 	    Sextallp2(opndp2) = Sextallp1(opndp1) >> -31-exponent;	\
464 	    Sextallp1(opndp1) = 0;					\
465 	}								\
466     }									\
467     else {								\
468 	sticky = Sextallp1(opndp1) | Sextallp2(opndp2);			\
469 	Sglext_setzero(opndp1,opndp2);					\
470     }									\
471     if (sticky) Sglext_setone_lowmantissap2(opndp2);			\
472     exponent = 0;							\
473   }
474