| /* Implementation of the NORM2 intrinsic |
| Copyright (C) 2010-2021 Free Software Foundation, Inc. |
| Contributed by Tobias Burnus <burnus@net-b.de> |
| |
| This file is part of the GNU Fortran runtime library (libgfortran). |
| |
| Libgfortran is free software; you can redistribute it and/or |
| modify it under the terms of the GNU General Public |
| License as published by the Free Software Foundation; either |
| version 3 of the License, or (at your option) any later version. |
| |
| Libgfortran is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| Under Section 7 of GPL version 3, you are granted additional |
| permissions described in the GCC Runtime Library Exception, version |
| 3.1, as published by the Free Software Foundation. |
| |
| You should have received a copy of the GNU General Public License and |
| a copy of the GCC Runtime Library Exception along with this program; |
| see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include "libgfortran.h" |
| |
| |
| |
| #if defined (HAVE_GFC_REAL_8) && defined (HAVE_GFC_REAL_8) && defined (HAVE_SQRT) && defined (HAVE_FABS) |
| |
| #define MATHFUNC(funcname) funcname |
| |
| |
| extern void norm2_r8 (gfc_array_r8 * const restrict, |
| gfc_array_r8 * const restrict, const index_type * const restrict); |
| export_proto(norm2_r8); |
| |
| void |
| norm2_r8 (gfc_array_r8 * const restrict retarray, |
| gfc_array_r8 * const restrict array, |
| const index_type * const restrict pdim) |
| { |
| index_type count[GFC_MAX_DIMENSIONS]; |
| index_type extent[GFC_MAX_DIMENSIONS]; |
| index_type sstride[GFC_MAX_DIMENSIONS]; |
| index_type dstride[GFC_MAX_DIMENSIONS]; |
| const GFC_REAL_8 * restrict base; |
| GFC_REAL_8 * restrict dest; |
| index_type rank; |
| index_type n; |
| index_type len; |
| index_type delta; |
| index_type dim; |
| int continue_loop; |
| |
| /* Make dim zero based to avoid confusion. */ |
| rank = GFC_DESCRIPTOR_RANK (array) - 1; |
| dim = (*pdim) - 1; |
| |
| if (unlikely (dim < 0 || dim > rank)) |
| { |
| runtime_error ("Dim argument incorrect in NORM intrinsic: " |
| "is %ld, should be between 1 and %ld", |
| (long int) dim + 1, (long int) rank + 1); |
| } |
| |
| len = GFC_DESCRIPTOR_EXTENT(array,dim); |
| if (len < 0) |
| len = 0; |
| delta = GFC_DESCRIPTOR_STRIDE(array,dim); |
| |
| for (n = 0; n < dim; n++) |
| { |
| sstride[n] = GFC_DESCRIPTOR_STRIDE(array,n); |
| extent[n] = GFC_DESCRIPTOR_EXTENT(array,n); |
| |
| if (extent[n] < 0) |
| extent[n] = 0; |
| } |
| for (n = dim; n < rank; n++) |
| { |
| sstride[n] = GFC_DESCRIPTOR_STRIDE(array, n + 1); |
| extent[n] = GFC_DESCRIPTOR_EXTENT(array, n + 1); |
| |
| if (extent[n] < 0) |
| extent[n] = 0; |
| } |
| |
| if (retarray->base_addr == NULL) |
| { |
| size_t alloc_size, str; |
| |
| for (n = 0; n < rank; n++) |
| { |
| if (n == 0) |
| str = 1; |
| else |
| str = GFC_DESCRIPTOR_STRIDE(retarray,n-1) * extent[n-1]; |
| |
| GFC_DIMENSION_SET(retarray->dim[n], 0, extent[n] - 1, str); |
| |
| } |
| |
| retarray->offset = 0; |
| retarray->dtype.rank = rank; |
| |
| alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1]; |
| |
| retarray->base_addr = xmallocarray (alloc_size, sizeof (GFC_REAL_8)); |
| if (alloc_size == 0) |
| { |
| /* Make sure we have a zero-sized array. */ |
| GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1); |
| return; |
| |
| } |
| } |
| else |
| { |
| if (rank != GFC_DESCRIPTOR_RANK (retarray)) |
| runtime_error ("rank of return array incorrect in" |
| " NORM intrinsic: is %ld, should be %ld", |
| (long int) (GFC_DESCRIPTOR_RANK (retarray)), |
| (long int) rank); |
| |
| if (unlikely (compile_options.bounds_check)) |
| bounds_ifunction_return ((array_t *) retarray, extent, |
| "return value", "NORM"); |
| } |
| |
| for (n = 0; n < rank; n++) |
| { |
| count[n] = 0; |
| dstride[n] = GFC_DESCRIPTOR_STRIDE(retarray,n); |
| if (extent[n] <= 0) |
| return; |
| } |
| |
| base = array->base_addr; |
| dest = retarray->base_addr; |
| |
| continue_loop = 1; |
| while (continue_loop) |
| { |
| const GFC_REAL_8 * restrict src; |
| GFC_REAL_8 result; |
| src = base; |
| { |
| |
| GFC_REAL_8 scale; |
| result = 0; |
| scale = 1; |
| if (len <= 0) |
| *dest = 0; |
| else |
| { |
| #if ! defined HAVE_BACK_ARG |
| for (n = 0; n < len; n++, src += delta) |
| { |
| #endif |
| |
| if (*src != 0) |
| { |
| GFC_REAL_8 absX, val; |
| absX = MATHFUNC(fabs) (*src); |
| if (scale < absX) |
| { |
| val = scale / absX; |
| result = 1 + result * val * val; |
| scale = absX; |
| } |
| else |
| { |
| val = absX / scale; |
| result += val * val; |
| } |
| } |
| } |
| result = scale * MATHFUNC(sqrt) (result); |
| *dest = result; |
| } |
| } |
| /* Advance to the next element. */ |
| count[0]++; |
| base += sstride[0]; |
| dest += dstride[0]; |
| n = 0; |
| while (count[n] == extent[n]) |
| { |
| /* When we get to the end of a dimension, reset it and increment |
| the next dimension. */ |
| count[n] = 0; |
| /* We could precalculate these products, but this is a less |
| frequently used path so probably not worth it. */ |
| base -= sstride[n] * extent[n]; |
| dest -= dstride[n] * extent[n]; |
| n++; |
| if (n >= rank) |
| { |
| /* Break out of the loop. */ |
| continue_loop = 0; |
| break; |
| } |
| else |
| { |
| count[n]++; |
| base += sstride[n]; |
| dest += dstride[n]; |
| } |
| } |
| } |
| } |
| |
| #endif |