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Diffstat (limited to 'gcc/ada/cuintp.c')
| -rw-r--r-- | gcc/ada/cuintp.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/gcc/ada/cuintp.c b/gcc/ada/cuintp.c new file mode 100644 index 00000000000..8b1835b67a2 --- /dev/null +++ b/gcc/ada/cuintp.c @@ -0,0 +1,110 @@ +/**************************************************************************** + * * + * GNAT COMPILER COMPONENTS * + * * + * C U I N T P * + * * + * C Implementation File * + * * + * $Revision: 1.1 $ + * * + * Copyright (C) 1992-2001 Free Software Foundation, Inc. * + * * + * GNAT is free software; you can redistribute it and/or modify it under * + * terms of the GNU General Public License as published by the Free Soft- * + * ware Foundation; either version 2, or (at your option) any later ver- * + * sion. GNAT is distributed in the hope that it will be useful, but WITH- * + * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * + * for more details. You should have received a copy of the GNU General * + * Public License distributed with GNAT; see file COPYING. If not, write * + * to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, * + * MA 02111-1307, USA. * + * * + * GNAT was originally developed by the GNAT team at New York University. * + * It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). * + * * + ****************************************************************************/ + +/* This file corresponds to the Ada package body Uintp. It was created + manually from the files uintp.ads and uintp.adb. */ + +#include "config.h" +#include "system.h" +#include "tree.h" +#include "ada.h" +#include "types.h" +#include "uintp.h" +#include "atree.h" +#include "elists.h" +#include "nlists.h" +#include "stringt.h" +#include "fe.h" +#include "gigi.h" + +/* Universal integers are represented by the Uint type which is an index into + the Uints_Ptr table containing Uint_Entry values. A Uint_Entry contains an + index and length for getting the "digits" of the universal integer from the + Udigits_Ptr table. + + For efficiency, this method is used only for integer values larger than the + constant Uint_Bias. If a Uint is less than this constant, then it contains + the integer value itself. The origin of the Uints_Ptr table is adjusted so + that a Uint value of Uint_Bias indexes the first element. */ + +/* Similarly to UI_To_Int, but return a GCC INTEGER_CST. Overflow is tested + by the constant-folding used to build the node. TYPE is the GCC type of the + resulting node. */ + +tree +UI_To_gnu (Input, type) + Uint Input; + tree type; +{ + tree gnu_ret; + + if (Input <= Uint_Direct_Last) + gnu_ret = convert (type, build_int_2 (Input - Uint_Direct_Bias, + Input < Uint_Direct_Bias ? -1 : 0)); + else + { + Int Idx = Uints_Ptr[Input].Loc; + Pos Length = Uints_Ptr[Input].Length; + Int First = Udigits_Ptr[Idx]; + /* Do computations in integer type or TYPE whichever is wider, then + convert later. This avoid overflow if type is short integer. */ + tree comp_type + = (TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node) + ? type : integer_type_node); + tree gnu_base = convert (comp_type, build_int_2 (Base, 0)); + + if (Length <= 0) + gigi_abort (601); + + gnu_ret = convert (comp_type, build_int_2 (First, First < 0 ? -1 : 0)); + if (First < 0) + for (Idx++, Length--; Length; Idx++, Length--) + gnu_ret = fold (build (MINUS_EXPR, comp_type, + fold (build (MULT_EXPR, comp_type, + gnu_ret, gnu_base)), + convert (comp_type, + build_int_2 (Udigits_Ptr[Idx], 0)))); + else + for (Idx++, Length--; Length; Idx++, Length--) + gnu_ret = fold (build (PLUS_EXPR, comp_type, + fold (build (MULT_EXPR, comp_type, + gnu_ret, gnu_base)), + convert (comp_type, + build_int_2 (Udigits_Ptr[Idx], 0)))); + } + + gnu_ret = convert (type, gnu_ret); + + /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on GNU_RET. */ + while ((TREE_CODE (gnu_ret) == NOP_EXPR + || TREE_CODE (gnu_ret) == NON_LVALUE_EXPR) + && TREE_TYPE (TREE_OPERAND (gnu_ret, 0)) == TREE_TYPE (gnu_ret)) + gnu_ret = TREE_OPERAND (gnu_ret, 0); + + return gnu_ret; +} |