1 /* Generic implementation of the CSHIFT intrinsic
2    Copyright (C) 2003-2018 Free Software Foundation, Inc.
3    Contributed by Feng Wang <wf_cs@yahoo.com>
4 
5 This file is part of the GNU Fortran runtime library (libgfortran).
6 
7 Libgfortran is free software; you can redistribute it and/or
8 modify it under the terms of the GNU General Public
9 License as published by the Free Software Foundation; either
10 version 3 of the License, or (at your option) any later version.
11 
12 Libgfortran is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 Under Section 7 of GPL version 3, you are granted additional
18 permissions described in the GCC Runtime Library Exception, version
19 3.1, as published by the Free Software Foundation.
20 
21 You should have received a copy of the GNU General Public License and
22 a copy of the GCC Runtime Library Exception along with this program;
23 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
24 <http://www.gnu.org/licenses/>.  */
25 
26 #include "libgfortran.h"
27 #include <string.h>
28 
29 static void
cshift0(gfc_array_char * ret,const gfc_array_char * array,ptrdiff_t shift,int which,index_type size)30 cshift0 (gfc_array_char * ret, const gfc_array_char * array,
31 	 ptrdiff_t shift, int which, index_type size)
32 {
33   /* r.* indicates the return array.  */
34   index_type rstride[GFC_MAX_DIMENSIONS];
35   index_type rstride0;
36   index_type roffset;
37   char *rptr;
38 
39   /* s.* indicates the source array.  */
40   index_type sstride[GFC_MAX_DIMENSIONS];
41   index_type sstride0;
42   index_type soffset;
43   const char *sptr;
44 
45   index_type count[GFC_MAX_DIMENSIONS];
46   index_type extent[GFC_MAX_DIMENSIONS];
47   index_type dim;
48   index_type len;
49   index_type n;
50   index_type arraysize;
51 
52   index_type type_size;
53 
54   if (which < 1 || which > GFC_DESCRIPTOR_RANK (array))
55     runtime_error ("Argument 'DIM' is out of range in call to 'CSHIFT'");
56 
57   arraysize = size0 ((array_t *) array);
58 
59   if (ret->base_addr == NULL)
60     {
61       int i;
62 
63       ret->offset = 0;
64       GFC_DTYPE_COPY(ret,array);
65       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
66         {
67 	  index_type ub, str;
68 
69           ub = GFC_DESCRIPTOR_EXTENT(array,i) - 1;
70 
71           if (i == 0)
72             str = 1;
73           else
74             str = GFC_DESCRIPTOR_EXTENT(ret,i-1) *
75 	      GFC_DESCRIPTOR_STRIDE(ret,i-1);
76 
77 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
78         }
79 
80       /* xmallocarray allocates a single byte for zero size.  */
81       ret->base_addr = xmallocarray (arraysize, size);
82     }
83   else if (unlikely (compile_options.bounds_check))
84     {
85       bounds_equal_extents ((array_t *) ret, (array_t *) array,
86 				 "return value", "CSHIFT");
87     }
88 
89   if (arraysize == 0)
90     return;
91 
92   type_size = GFC_DTYPE_TYPE_SIZE (array);
93 
94   switch(type_size)
95     {
96     case GFC_DTYPE_LOGICAL_1:
97     case GFC_DTYPE_INTEGER_1:
98       cshift0_i1 ((gfc_array_i1 *)ret, (gfc_array_i1 *) array, shift, which);
99       return;
100 
101     case GFC_DTYPE_LOGICAL_2:
102     case GFC_DTYPE_INTEGER_2:
103       cshift0_i2 ((gfc_array_i2 *)ret, (gfc_array_i2 *) array, shift, which);
104       return;
105 
106     case GFC_DTYPE_LOGICAL_4:
107     case GFC_DTYPE_INTEGER_4:
108       cshift0_i4 ((gfc_array_i4 *)ret, (gfc_array_i4 *) array, shift, which);
109       return;
110 
111     case GFC_DTYPE_LOGICAL_8:
112     case GFC_DTYPE_INTEGER_8:
113       cshift0_i8 ((gfc_array_i8 *)ret, (gfc_array_i8 *) array, shift, which);
114       return;
115 
116 #ifdef HAVE_GFC_INTEGER_16
117     case GFC_DTYPE_LOGICAL_16:
118     case GFC_DTYPE_INTEGER_16:
119       cshift0_i16 ((gfc_array_i16 *)ret, (gfc_array_i16 *) array, shift,
120 		   which);
121       return;
122 #endif
123 
124     case GFC_DTYPE_REAL_4:
125       cshift0_r4 ((gfc_array_r4 *)ret, (gfc_array_r4 *) array, shift, which);
126       return;
127 
128     case GFC_DTYPE_REAL_8:
129       cshift0_r8 ((gfc_array_r8 *)ret, (gfc_array_r8 *) array, shift, which);
130       return;
131 
132 /* FIXME: This here is a hack, which will have to be removed when
133    the array descriptor is reworked.  Currently, we don't store the
134    kind value for the type, but only the size.  Because on targets with
135    __float128, we have sizeof(logn double) == sizeof(__float128),
136    we cannot discriminate here and have to fall back to the generic
137    handling (which is suboptimal).  */
138 #if !defined(GFC_REAL_16_IS_FLOAT128)
139 # ifdef HAVE_GFC_REAL_10
140     case GFC_DTYPE_REAL_10:
141       cshift0_r10 ((gfc_array_r10 *)ret, (gfc_array_r10 *) array, shift,
142 		   which);
143       return;
144 # endif
145 
146 # ifdef HAVE_GFC_REAL_16
147     case GFC_DTYPE_REAL_16:
148       cshift0_r16 ((gfc_array_r16 *)ret, (gfc_array_r16 *) array, shift,
149 		   which);
150       return;
151 # endif
152 #endif
153 
154     case GFC_DTYPE_COMPLEX_4:
155       cshift0_c4 ((gfc_array_c4 *)ret, (gfc_array_c4 *) array, shift, which);
156       return;
157 
158     case GFC_DTYPE_COMPLEX_8:
159       cshift0_c8 ((gfc_array_c8 *)ret, (gfc_array_c8 *) array, shift, which);
160       return;
161 
162 /* FIXME: This here is a hack, which will have to be removed when
163    the array descriptor is reworked.  Currently, we don't store the
164    kind value for the type, but only the size.  Because on targets with
165    __float128, we have sizeof(logn double) == sizeof(__float128),
166    we cannot discriminate here and have to fall back to the generic
167    handling (which is suboptimal).  */
168 #if !defined(GFC_REAL_16_IS_FLOAT128)
169 # ifdef HAVE_GFC_COMPLEX_10
170     case GFC_DTYPE_COMPLEX_10:
171       cshift0_c10 ((gfc_array_c10 *)ret, (gfc_array_c10 *) array, shift,
172 		   which);
173       return;
174 # endif
175 
176 # ifdef HAVE_GFC_COMPLEX_16
177     case GFC_DTYPE_COMPLEX_16:
178       cshift0_c16 ((gfc_array_c16 *)ret, (gfc_array_c16 *) array, shift,
179 		   which);
180       return;
181 # endif
182 #endif
183 
184     default:
185       break;
186     }
187 
188   switch (size)
189     {
190       /* Let's check the actual alignment of the data pointers.  If they
191 	 are suitably aligned, we can safely call the unpack functions.  */
192 
193     case sizeof (GFC_INTEGER_1):
194       cshift0_i1 ((gfc_array_i1 *) ret, (gfc_array_i1 *) array, shift,
195 		  which);
196       break;
197 
198     case sizeof (GFC_INTEGER_2):
199       if (GFC_UNALIGNED_2(ret->base_addr) || GFC_UNALIGNED_2(array->base_addr))
200 	break;
201       else
202 	{
203 	  cshift0_i2 ((gfc_array_i2 *) ret, (gfc_array_i2 *) array, shift,
204 		      which);
205 	  return;
206 	}
207 
208     case sizeof (GFC_INTEGER_4):
209       if (GFC_UNALIGNED_4(ret->base_addr) || GFC_UNALIGNED_4(array->base_addr))
210 	break;
211       else
212 	{
213 	  cshift0_i4 ((gfc_array_i4 *)ret, (gfc_array_i4 *) array, shift,
214 		      which);
215 	  return;
216 	}
217 
218     case sizeof (GFC_INTEGER_8):
219       if (GFC_UNALIGNED_8(ret->base_addr) || GFC_UNALIGNED_8(array->base_addr))
220 	{
221 	  /* Let's try to use the complex routines.  First, a sanity
222 	     check that the sizes match; this should be optimized to
223 	     a no-op.  */
224 	  if (sizeof(GFC_INTEGER_8) != sizeof(GFC_COMPLEX_4))
225 	    break;
226 
227 	  if (GFC_UNALIGNED_C4(ret->base_addr)
228 	      || GFC_UNALIGNED_C4(array->base_addr))
229 	    break;
230 
231 	  cshift0_c4 ((gfc_array_c4 *) ret, (gfc_array_c4 *) array, shift,
232 		      which);
233 	  return;
234 	}
235       else
236 	{
237 	  cshift0_i8 ((gfc_array_i8 *)ret, (gfc_array_i8 *) array, shift,
238 		      which);
239 	  return;
240 	}
241 
242 #ifdef HAVE_GFC_INTEGER_16
243     case sizeof (GFC_INTEGER_16):
244       if (GFC_UNALIGNED_16(ret->base_addr)
245 	  || GFC_UNALIGNED_16(array->base_addr))
246 	{
247 	  /* Let's try to use the complex routines.  First, a sanity
248 	     check that the sizes match; this should be optimized to
249 	     a no-op.  */
250 	  if (sizeof(GFC_INTEGER_16) != sizeof(GFC_COMPLEX_8))
251 	    break;
252 
253 	  if (GFC_UNALIGNED_C8(ret->base_addr)
254 	      || GFC_UNALIGNED_C8(array->base_addr))
255 	    break;
256 
257 	  cshift0_c8 ((gfc_array_c8 *) ret, (gfc_array_c8 *) array, shift,
258 		      which);
259 	  return;
260 	}
261       else
262 	{
263 	  cshift0_i16 ((gfc_array_i16 *) ret, (gfc_array_i16 *) array,
264 		       shift, which);
265 	  return;
266 	}
267 #else
268     case sizeof (GFC_COMPLEX_8):
269 
270       if (GFC_UNALIGNED_C8(ret->base_addr)
271 	  || GFC_UNALIGNED_C8(array->base_addr))
272 	break;
273       else
274 	{
275 	  cshift0_c8 ((gfc_array_c8 *) ret, (gfc_array_c8 *) array, shift,
276 		      which);
277 	  return;
278 	}
279 #endif
280 
281     default:
282       break;
283     }
284 
285 
286   which = which - 1;
287   sstride[0] = 0;
288   rstride[0] = 0;
289 
290   extent[0] = 1;
291   count[0] = 0;
292   n = 0;
293   /* Initialized for avoiding compiler warnings.  */
294   roffset = size;
295   soffset = size;
296   len = 0;
297 
298   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
299     {
300       if (dim == which)
301         {
302           roffset = GFC_DESCRIPTOR_STRIDE_BYTES(ret,dim);
303           if (roffset == 0)
304             roffset = size;
305           soffset = GFC_DESCRIPTOR_STRIDE_BYTES(array,dim);
306           if (soffset == 0)
307             soffset = size;
308           len = GFC_DESCRIPTOR_EXTENT(array,dim);
309         }
310       else
311         {
312           count[n] = 0;
313           extent[n] = GFC_DESCRIPTOR_EXTENT(array,dim);
314           rstride[n] = GFC_DESCRIPTOR_STRIDE_BYTES(ret,dim);
315           sstride[n] = GFC_DESCRIPTOR_STRIDE_BYTES(array,dim);
316           n++;
317         }
318     }
319   if (sstride[0] == 0)
320     sstride[0] = size;
321   if (rstride[0] == 0)
322     rstride[0] = size;
323 
324   dim = GFC_DESCRIPTOR_RANK (array);
325   rstride0 = rstride[0];
326   sstride0 = sstride[0];
327   rptr = ret->base_addr;
328   sptr = array->base_addr;
329 
330   shift = len == 0 ? 0 : shift % (ptrdiff_t)len;
331   if (shift < 0)
332     shift += len;
333 
334   while (rptr)
335     {
336       /* Do the shift for this dimension.  */
337 
338       /* If elements are contiguous, perform the operation
339 	 in two block moves.  */
340       if (soffset == size && roffset == size)
341 	{
342 	  size_t len1 = shift * size;
343 	  size_t len2 = (len - shift) * size;
344 	  memcpy (rptr, sptr + len1, len2);
345 	  memcpy (rptr + len2, sptr, len1);
346 	}
347       else
348 	{
349 	  /* Otherwise, we'll have to perform the copy one element at
350 	     a time.  */
351 	  char *dest = rptr;
352 	  const char *src = &sptr[shift * soffset];
353 
354 	  for (n = 0; n < len - shift; n++)
355 	    {
356 	      memcpy (dest, src, size);
357 	      dest += roffset;
358 	      src += soffset;
359 	    }
360 	  for (src = sptr, n = 0; n < shift; n++)
361 	    {
362 	      memcpy (dest, src, size);
363 	      dest += roffset;
364 	      src += soffset;
365 	    }
366 	}
367 
368       /* Advance to the next section.  */
369       rptr += rstride0;
370       sptr += sstride0;
371       count[0]++;
372       n = 0;
373       while (count[n] == extent[n])
374         {
375           /* When we get to the end of a dimension, reset it and increment
376              the next dimension.  */
377           count[n] = 0;
378           /* We could precalculate these products, but this is a less
379              frequently used path so probably not worth it.  */
380           rptr -= rstride[n] * extent[n];
381           sptr -= sstride[n] * extent[n];
382           n++;
383           if (n >= dim - 1)
384             {
385               /* Break out of the loop.  */
386               rptr = NULL;
387               break;
388             }
389           else
390             {
391               count[n]++;
392               rptr += rstride[n];
393               sptr += sstride[n];
394             }
395         }
396     }
397 }
398 
399 #define DEFINE_CSHIFT(N)						      \
400   extern void cshift0_##N (gfc_array_char *, const gfc_array_char *,	      \
401 			   const GFC_INTEGER_##N *, const GFC_INTEGER_##N *); \
402   export_proto(cshift0_##N);						      \
403 									      \
404   void									      \
405   cshift0_##N (gfc_array_char *ret, const gfc_array_char *array,	      \
406 	       const GFC_INTEGER_##N *pshift, const GFC_INTEGER_##N *pdim)    \
407   {									      \
408     cshift0 (ret, array, *pshift, pdim ? *pdim : 1,			      \
409 	     GFC_DESCRIPTOR_SIZE (array));				      \
410   }									      \
411 									      \
412   extern void cshift0_##N##_char (gfc_array_char *, GFC_INTEGER_4,	      \
413 				  const gfc_array_char *,		      \
414 				  const GFC_INTEGER_##N *,		      \
415 				  const GFC_INTEGER_##N *, GFC_INTEGER_4);    \
416   export_proto(cshift0_##N##_char);					      \
417 									      \
418   void									      \
419   cshift0_##N##_char (gfc_array_char *ret,				      \
420 		      GFC_INTEGER_4 ret_length __attribute__((unused)),	      \
421 		      const gfc_array_char *array,			      \
422 		      const GFC_INTEGER_##N *pshift,			      \
423 		      const GFC_INTEGER_##N *pdim,			      \
424 		      GFC_INTEGER_4 array_length)			      \
425   {									      \
426     cshift0 (ret, array, *pshift, pdim ? *pdim : 1, array_length);	      \
427   }									      \
428 									      \
429   extern void cshift0_##N##_char4 (gfc_array_char *, GFC_INTEGER_4,	      \
430 				   const gfc_array_char *,		      \
431 				   const GFC_INTEGER_##N *,		      \
432 				   const GFC_INTEGER_##N *, GFC_INTEGER_4);   \
433   export_proto(cshift0_##N##_char4);					      \
434 									      \
435   void									      \
436   cshift0_##N##_char4 (gfc_array_char *ret,				      \
437 		       GFC_INTEGER_4 ret_length __attribute__((unused)),      \
438 		       const gfc_array_char *array,			      \
439 		       const GFC_INTEGER_##N *pshift,			      \
440 		       const GFC_INTEGER_##N *pdim,			      \
441 		       GFC_INTEGER_4 array_length)			      \
442   {									      \
443     cshift0 (ret, array, *pshift, pdim ? *pdim : 1,			      \
444 	     array_length * sizeof (gfc_char4_t));			      \
445   }
446 
447 DEFINE_CSHIFT (1);
448 DEFINE_CSHIFT (2);
449 DEFINE_CSHIFT (4);
450 DEFINE_CSHIFT (8);
451 #ifdef HAVE_GFC_INTEGER_16
452 DEFINE_CSHIFT (16);
453 #endif
454