/* Helper function for cshift functions. Copyright (C) 2008-2017 Free Software Foundation, Inc. Contributed by Thomas Koenig 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 . */ #include "libgfortran.h" #include #if defined (HAVE_GFC_REAL_16) void cshift0_r16 (gfc_array_r16 *ret, const gfc_array_r16 *array, ptrdiff_t shift, int which) { /* r.* indicates the return array. */ index_type rstride[GFC_MAX_DIMENSIONS]; index_type rstride0; index_type roffset; GFC_REAL_16 *rptr; /* s.* indicates the source array. */ index_type sstride[GFC_MAX_DIMENSIONS]; index_type sstride0; index_type soffset; const GFC_REAL_16 *sptr; index_type count[GFC_MAX_DIMENSIONS]; index_type extent[GFC_MAX_DIMENSIONS]; index_type dim; index_type len; index_type n; bool do_blocked; index_type r_ex, a_ex; which = which - 1; sstride[0] = 0; rstride[0] = 0; extent[0] = 1; count[0] = 0; n = 0; /* Initialized for avoiding compiler warnings. */ roffset = 1; soffset = 1; len = 0; r_ex = 1; a_ex = 1; if (which > 0) { /* Test if both ret and array are contiguous. */ do_blocked = true; dim = GFC_DESCRIPTOR_RANK (array); for (n = 0; n < dim; n ++) { index_type rs, as; rs = GFC_DESCRIPTOR_STRIDE (ret, n); if (rs != r_ex) { do_blocked = false; break; } as = GFC_DESCRIPTOR_STRIDE (array, n); if (as != a_ex) { do_blocked = false; break; } r_ex *= GFC_DESCRIPTOR_EXTENT (ret, n); a_ex *= GFC_DESCRIPTOR_EXTENT (array, n); } } else do_blocked = false; n = 0; if (do_blocked) { /* For contiguous arrays, use the relationship that dimension(n1,n2,n3) :: a, b b = cshift(a,sh,3) can be dealt with as if dimension(n1*n2*n3) :: an, bn bn = cshift(a,sh*n1*n2,1) we can used a more blocked algorithm for dim>1. */ sstride[0] = 1; rstride[0] = 1; roffset = 1; soffset = 1; len = GFC_DESCRIPTOR_STRIDE(array, which) * GFC_DESCRIPTOR_EXTENT(array, which); shift *= GFC_DESCRIPTOR_STRIDE(array, which); for (dim = which + 1; dim < GFC_DESCRIPTOR_RANK (array); dim++) { count[n] = 0; extent[n] = GFC_DESCRIPTOR_EXTENT(array,dim); rstride[n] = GFC_DESCRIPTOR_STRIDE(ret,dim); sstride[n] = GFC_DESCRIPTOR_STRIDE(array,dim); n++; } dim = GFC_DESCRIPTOR_RANK (array) - which; } else { for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++) { if (dim == which) { roffset = GFC_DESCRIPTOR_STRIDE(ret,dim); if (roffset == 0) roffset = 1; soffset = GFC_DESCRIPTOR_STRIDE(array,dim); if (soffset == 0) soffset = 1; len = GFC_DESCRIPTOR_EXTENT(array,dim); } else { count[n] = 0; extent[n] = GFC_DESCRIPTOR_EXTENT(array,dim); rstride[n] = GFC_DESCRIPTOR_STRIDE(ret,dim); sstride[n] = GFC_DESCRIPTOR_STRIDE(array,dim); n++; } } if (sstride[0] == 0) sstride[0] = 1; if (rstride[0] == 0) rstride[0] = 1; dim = GFC_DESCRIPTOR_RANK (array); } rstride0 = rstride[0]; sstride0 = sstride[0]; rptr = ret->base_addr; sptr = array->base_addr; /* Avoid the costly modulo for trivially in-bound shifts. */ if (shift < 0 || shift >= len) { shift = len == 0 ? 0 : shift % (ptrdiff_t)len; if (shift < 0) shift += len; } while (rptr) { /* Do the shift for this dimension. */ /* If elements are contiguous, perform the operation in two block moves. */ if (soffset == 1 && roffset == 1) { size_t len1 = shift * sizeof (GFC_REAL_16); size_t len2 = (len - shift) * sizeof (GFC_REAL_16); memcpy (rptr, sptr + shift, len2); memcpy (rptr + (len - shift), sptr, len1); } else { /* Otherwise, we will have to perform the copy one element at a time. */ GFC_REAL_16 *dest = rptr; const GFC_REAL_16 *src = &sptr[shift * soffset]; for (n = 0; n < len - shift; n++) { *dest = *src; dest += roffset; src += soffset; } for (src = sptr, n = 0; n < shift; n++) { *dest = *src; dest += roffset; src += soffset; } } /* Advance to the next section. */ rptr += rstride0; sptr += sstride0; count[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. */ rptr -= rstride[n] * extent[n]; sptr -= sstride[n] * extent[n]; n++; if (n >= dim - 1) { /* Break out of the loop. */ rptr = NULL; break; } else { count[n]++; rptr += rstride[n]; sptr += sstride[n]; } } } return; } #endif