1 /* Implementation of the NORM2 intrinsic
2 Copyright 2010 Free Software Foundation, Inc.
3 Contributed by Tobias Burnus <burnus@net-b.de>
5 This file is part of the GNU Fortran runtime library (libgfortran).
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.
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.
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.
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/>. */
26 #include "libgfortran.h"
33 #if defined (HAVE_GFC_REAL_4) && defined (HAVE_GFC_REAL_4) && defined (HAVE_SQRTF) && defined (HAVE_FABSF)
35 #define MATHFUNC(funcname) funcname ## f
38 extern void norm2_r4 (gfc_array_r4
* const restrict
,
39 gfc_array_r4
* const restrict
, const index_type
* const restrict
);
40 export_proto(norm2_r4
);
43 norm2_r4 (gfc_array_r4
* const restrict retarray
,
44 gfc_array_r4
* const restrict array
,
45 const index_type
* const restrict pdim
)
47 index_type count
[GFC_MAX_DIMENSIONS
];
48 index_type extent
[GFC_MAX_DIMENSIONS
];
49 index_type sstride
[GFC_MAX_DIMENSIONS
];
50 index_type dstride
[GFC_MAX_DIMENSIONS
];
51 const GFC_REAL_4
* restrict base
;
52 GFC_REAL_4
* restrict dest
;
60 /* Make dim zero based to avoid confusion. */
62 rank
= GFC_DESCRIPTOR_RANK (array
) - 1;
64 len
= GFC_DESCRIPTOR_EXTENT(array
,dim
);
67 delta
= GFC_DESCRIPTOR_STRIDE(array
,dim
);
69 for (n
= 0; n
< dim
; n
++)
71 sstride
[n
] = GFC_DESCRIPTOR_STRIDE(array
,n
);
72 extent
[n
] = GFC_DESCRIPTOR_EXTENT(array
,n
);
77 for (n
= dim
; n
< rank
; n
++)
79 sstride
[n
] = GFC_DESCRIPTOR_STRIDE(array
, n
+ 1);
80 extent
[n
] = GFC_DESCRIPTOR_EXTENT(array
, n
+ 1);
86 if (retarray
->data
== NULL
)
88 size_t alloc_size
, str
;
90 for (n
= 0; n
< rank
; n
++)
95 str
= GFC_DESCRIPTOR_STRIDE(retarray
,n
-1) * extent
[n
-1];
97 GFC_DIMENSION_SET(retarray
->dim
[n
], 0, extent
[n
] - 1, str
);
101 retarray
->offset
= 0;
102 retarray
->dtype
= (array
->dtype
& ~GFC_DTYPE_RANK_MASK
) | rank
;
104 alloc_size
= sizeof (GFC_REAL_4
) * GFC_DESCRIPTOR_STRIDE(retarray
,rank
-1)
109 /* Make sure we have a zero-sized array. */
110 GFC_DIMENSION_SET(retarray
->dim
[0], 0, -1, 1);
115 retarray
->data
= internal_malloc_size (alloc_size
);
119 if (rank
!= GFC_DESCRIPTOR_RANK (retarray
))
120 runtime_error ("rank of return array incorrect in"
121 " NORM intrinsic: is %ld, should be %ld",
122 (long int) (GFC_DESCRIPTOR_RANK (retarray
)),
125 if (unlikely (compile_options
.bounds_check
))
126 bounds_ifunction_return ((array_t
*) retarray
, extent
,
127 "return value", "NORM");
130 for (n
= 0; n
< rank
; n
++)
133 dstride
[n
] = GFC_DESCRIPTOR_STRIDE(retarray
,n
);
139 dest
= retarray
->data
;
142 while (continue_loop
)
144 const GFC_REAL_4
* restrict src
;
156 for (n
= 0; n
< len
; n
++, src
+= delta
)
161 GFC_REAL_4 absX
, val
;
162 absX
= MATHFUNC(fabs
) (*src
);
166 result
= 1 + result
* val
* val
;
176 result
= scale
* MATHFUNC(sqrt
) (result
);
180 /* Advance to the next element. */
185 while (count
[n
] == extent
[n
])
187 /* When we get to the end of a dimension, reset it and increment
188 the next dimension. */
190 /* We could precalculate these products, but this is a less
191 frequently used path so probably not worth it. */
192 base
-= sstride
[n
] * extent
[n
];
193 dest
-= dstride
[n
] * extent
[n
];
197 /* Break out of the look. */