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823 lines
26 KiB
C
823 lines
26 KiB
C
/* Utility routines for data type conversion for GCC.
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Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1997, 1998,
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2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 2, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING. If not, write to the Free
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Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, USA. */
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/* These routines are somewhat language-independent utility function
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intended to be called by the language-specific convert () functions. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "tree.h"
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#include "flags.h"
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#include "convert.h"
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#include "toplev.h"
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#include "langhooks.h"
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#include "real.h"
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/* Convert EXPR to some pointer or reference type TYPE.
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EXPR must be pointer, reference, integer, enumeral, or literal zero;
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in other cases error is called. */
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tree
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convert_to_pointer (tree type, tree expr)
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{
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if (TREE_TYPE (expr) == type)
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return expr;
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if (integer_zerop (expr))
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{
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tree t = build_int_cst (type, 0);
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if (TREE_OVERFLOW (expr) || TREE_CONSTANT_OVERFLOW (expr))
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t = force_fit_type (t, 0, TREE_OVERFLOW (expr),
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TREE_CONSTANT_OVERFLOW (expr));
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return t;
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}
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switch (TREE_CODE (TREE_TYPE (expr)))
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{
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case POINTER_TYPE:
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case REFERENCE_TYPE:
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return fold_build1 (NOP_EXPR, type, expr);
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case INTEGER_TYPE:
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case ENUMERAL_TYPE:
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case BOOLEAN_TYPE:
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if (TYPE_PRECISION (TREE_TYPE (expr)) != POINTER_SIZE)
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expr = fold_build1 (NOP_EXPR,
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lang_hooks.types.type_for_size (POINTER_SIZE, 0),
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expr);
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return fold_build1 (CONVERT_EXPR, type, expr);
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default:
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error ("cannot convert to a pointer type");
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return convert_to_pointer (type, integer_zero_node);
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}
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}
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/* Avoid any floating point extensions from EXP. */
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tree
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strip_float_extensions (tree exp)
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{
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tree sub, expt, subt;
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/* For floating point constant look up the narrowest type that can hold
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it properly and handle it like (type)(narrowest_type)constant.
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This way we can optimize for instance a=a*2.0 where "a" is float
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but 2.0 is double constant. */
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if (TREE_CODE (exp) == REAL_CST)
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{
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REAL_VALUE_TYPE orig;
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tree type = NULL;
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orig = TREE_REAL_CST (exp);
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if (TYPE_PRECISION (TREE_TYPE (exp)) > TYPE_PRECISION (float_type_node)
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&& exact_real_truncate (TYPE_MODE (float_type_node), &orig))
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type = float_type_node;
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else if (TYPE_PRECISION (TREE_TYPE (exp))
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> TYPE_PRECISION (double_type_node)
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&& exact_real_truncate (TYPE_MODE (double_type_node), &orig))
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type = double_type_node;
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if (type)
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return build_real (type, real_value_truncate (TYPE_MODE (type), orig));
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}
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if (TREE_CODE (exp) != NOP_EXPR
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&& TREE_CODE (exp) != CONVERT_EXPR)
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return exp;
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sub = TREE_OPERAND (exp, 0);
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subt = TREE_TYPE (sub);
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expt = TREE_TYPE (exp);
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if (!FLOAT_TYPE_P (subt))
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return exp;
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if (TYPE_PRECISION (subt) > TYPE_PRECISION (expt))
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return exp;
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return strip_float_extensions (sub);
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}
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/* Convert EXPR to some floating-point type TYPE.
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EXPR must be float, integer, or enumeral;
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in other cases error is called. */
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tree
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convert_to_real (tree type, tree expr)
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{
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enum built_in_function fcode = builtin_mathfn_code (expr);
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tree itype = TREE_TYPE (expr);
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/* Disable until we figure out how to decide whether the functions are
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present in runtime. */
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/* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */
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if (optimize
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&& (TYPE_MODE (type) == TYPE_MODE (double_type_node)
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|| TYPE_MODE (type) == TYPE_MODE (float_type_node)))
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{
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switch (fcode)
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{
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#define CASE_MATHFN(FN) case BUILT_IN_##FN: case BUILT_IN_##FN##L:
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CASE_MATHFN (ACOS)
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CASE_MATHFN (ACOSH)
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CASE_MATHFN (ASIN)
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CASE_MATHFN (ASINH)
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CASE_MATHFN (ATAN)
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CASE_MATHFN (ATANH)
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CASE_MATHFN (CBRT)
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CASE_MATHFN (COS)
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CASE_MATHFN (COSH)
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CASE_MATHFN (ERF)
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CASE_MATHFN (ERFC)
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CASE_MATHFN (EXP)
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CASE_MATHFN (EXP10)
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CASE_MATHFN (EXP2)
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CASE_MATHFN (EXPM1)
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CASE_MATHFN (FABS)
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CASE_MATHFN (GAMMA)
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CASE_MATHFN (J0)
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CASE_MATHFN (J1)
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CASE_MATHFN (LGAMMA)
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CASE_MATHFN (LOG)
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CASE_MATHFN (LOG10)
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CASE_MATHFN (LOG1P)
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CASE_MATHFN (LOG2)
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CASE_MATHFN (LOGB)
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CASE_MATHFN (POW10)
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CASE_MATHFN (SIN)
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CASE_MATHFN (SINH)
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CASE_MATHFN (SQRT)
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CASE_MATHFN (TAN)
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CASE_MATHFN (TANH)
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CASE_MATHFN (TGAMMA)
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CASE_MATHFN (Y0)
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CASE_MATHFN (Y1)
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#undef CASE_MATHFN
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{
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tree arg0 = strip_float_extensions (TREE_VALUE (TREE_OPERAND (expr, 1)));
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tree newtype = type;
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/* We have (outertype)sqrt((innertype)x). Choose the wider mode from
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the both as the safe type for operation. */
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if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (type))
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newtype = TREE_TYPE (arg0);
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/* Be careful about integer to fp conversions.
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These may overflow still. */
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if (FLOAT_TYPE_P (TREE_TYPE (arg0))
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&& TYPE_PRECISION (newtype) < TYPE_PRECISION (itype)
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&& (TYPE_MODE (newtype) == TYPE_MODE (double_type_node)
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|| TYPE_MODE (newtype) == TYPE_MODE (float_type_node)))
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{
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tree arglist;
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tree fn = mathfn_built_in (newtype, fcode);
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if (fn)
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{
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arglist = build_tree_list (NULL_TREE, fold (convert_to_real (newtype, arg0)));
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expr = build_function_call_expr (fn, arglist);
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if (newtype == type)
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return expr;
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}
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}
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}
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default:
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break;
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}
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}
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if (optimize
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&& (((fcode == BUILT_IN_FLOORL
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|| fcode == BUILT_IN_CEILL
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|| fcode == BUILT_IN_ROUNDL
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|| fcode == BUILT_IN_RINTL
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|| fcode == BUILT_IN_TRUNCL
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|| fcode == BUILT_IN_NEARBYINTL)
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&& (TYPE_MODE (type) == TYPE_MODE (double_type_node)
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|| TYPE_MODE (type) == TYPE_MODE (float_type_node)))
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|| ((fcode == BUILT_IN_FLOOR
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|| fcode == BUILT_IN_CEIL
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|| fcode == BUILT_IN_ROUND
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|| fcode == BUILT_IN_RINT
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|| fcode == BUILT_IN_TRUNC
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|| fcode == BUILT_IN_NEARBYINT)
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&& (TYPE_MODE (type) == TYPE_MODE (float_type_node)))))
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{
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tree fn = mathfn_built_in (type, fcode);
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if (fn)
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{
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tree arg
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= strip_float_extensions (TREE_VALUE (TREE_OPERAND (expr, 1)));
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/* Make sure (type)arg0 is an extension, otherwise we could end up
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changing (float)floor(double d) into floorf((float)d), which is
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incorrect because (float)d uses round-to-nearest and can round
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up to the next integer. */
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if (TYPE_PRECISION (type) >= TYPE_PRECISION (TREE_TYPE (arg)))
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return
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build_function_call_expr (fn,
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build_tree_list (NULL_TREE,
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fold (convert_to_real (type, arg))));
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}
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}
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/* Propagate the cast into the operation. */
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if (itype != type && FLOAT_TYPE_P (type))
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switch (TREE_CODE (expr))
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{
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/* Convert (float)-x into -(float)x. This is safe for
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round-to-nearest rounding mode. */
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case ABS_EXPR:
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case NEGATE_EXPR:
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if (!flag_rounding_math
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&& TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (expr)))
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return build1 (TREE_CODE (expr), type,
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fold (convert_to_real (type,
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TREE_OPERAND (expr, 0))));
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break;
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/* Convert (outertype)((innertype0)a+(innertype1)b)
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into ((newtype)a+(newtype)b) where newtype
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is the widest mode from all of these. */
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case PLUS_EXPR:
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case MINUS_EXPR:
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case MULT_EXPR:
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case RDIV_EXPR:
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{
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tree arg0 = strip_float_extensions (TREE_OPERAND (expr, 0));
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tree arg1 = strip_float_extensions (TREE_OPERAND (expr, 1));
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if (FLOAT_TYPE_P (TREE_TYPE (arg0))
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&& FLOAT_TYPE_P (TREE_TYPE (arg1)))
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{
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tree newtype = type;
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if (TYPE_MODE (TREE_TYPE (arg0)) == SDmode
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|| TYPE_MODE (TREE_TYPE (arg1)) == SDmode)
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newtype = dfloat32_type_node;
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if (TYPE_MODE (TREE_TYPE (arg0)) == DDmode
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|| TYPE_MODE (TREE_TYPE (arg1)) == DDmode)
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newtype = dfloat64_type_node;
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if (TYPE_MODE (TREE_TYPE (arg0)) == TDmode
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|| TYPE_MODE (TREE_TYPE (arg1)) == TDmode)
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newtype = dfloat128_type_node;
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if (newtype == dfloat32_type_node
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|| newtype == dfloat64_type_node
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|| newtype == dfloat128_type_node)
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{
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expr = build2 (TREE_CODE (expr), newtype,
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fold (convert_to_real (newtype, arg0)),
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fold (convert_to_real (newtype, arg1)));
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if (newtype == type)
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return expr;
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break;
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}
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if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (newtype))
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newtype = TREE_TYPE (arg0);
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if (TYPE_PRECISION (TREE_TYPE (arg1)) > TYPE_PRECISION (newtype))
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newtype = TREE_TYPE (arg1);
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if (TYPE_PRECISION (newtype) < TYPE_PRECISION (itype))
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{
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expr = build2 (TREE_CODE (expr), newtype,
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fold (convert_to_real (newtype, arg0)),
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fold (convert_to_real (newtype, arg1)));
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if (newtype == type)
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return expr;
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}
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}
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}
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break;
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default:
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break;
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}
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switch (TREE_CODE (TREE_TYPE (expr)))
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{
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case REAL_TYPE:
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/* Ignore the conversion if we don't need to store intermediate
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results and neither type is a decimal float. */
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return build1 ((flag_float_store
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|| DECIMAL_FLOAT_TYPE_P (type)
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|| DECIMAL_FLOAT_TYPE_P (itype))
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? CONVERT_EXPR : NOP_EXPR, type, expr);
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case INTEGER_TYPE:
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case ENUMERAL_TYPE:
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case BOOLEAN_TYPE:
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return build1 (FLOAT_EXPR, type, expr);
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case COMPLEX_TYPE:
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return convert (type,
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fold_build1 (REALPART_EXPR,
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TREE_TYPE (TREE_TYPE (expr)), expr));
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case POINTER_TYPE:
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case REFERENCE_TYPE:
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error ("pointer value used where a floating point value was expected");
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return convert_to_real (type, integer_zero_node);
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default:
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error ("aggregate value used where a float was expected");
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return convert_to_real (type, integer_zero_node);
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}
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}
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/* Convert EXPR to some integer (or enum) type TYPE.
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EXPR must be pointer, integer, discrete (enum, char, or bool), float, or
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vector; in other cases error is called.
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The result of this is always supposed to be a newly created tree node
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not in use in any existing structure. */
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tree
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convert_to_integer (tree type, tree expr)
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{
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enum tree_code ex_form = TREE_CODE (expr);
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tree intype = TREE_TYPE (expr);
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unsigned int inprec = TYPE_PRECISION (intype);
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unsigned int outprec = TYPE_PRECISION (type);
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/* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
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be. Consider `enum E = { a, b = (enum E) 3 };'. */
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if (!COMPLETE_TYPE_P (type))
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{
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error ("conversion to incomplete type");
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return error_mark_node;
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}
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/* Convert e.g. (long)round(d) -> lround(d). */
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/* If we're converting to char, we may encounter differing behavior
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between converting from double->char vs double->long->char.
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We're in "undefined" territory but we prefer to be conservative,
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so only proceed in "unsafe" math mode. */
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if (optimize
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&& (flag_unsafe_math_optimizations
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|| (long_integer_type_node
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&& outprec >= TYPE_PRECISION (long_integer_type_node))))
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{
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tree s_expr = strip_float_extensions (expr);
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tree s_intype = TREE_TYPE (s_expr);
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const enum built_in_function fcode = builtin_mathfn_code (s_expr);
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tree fn = 0;
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switch (fcode)
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{
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CASE_FLT_FN (BUILT_IN_CEIL):
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/* Only convert in ISO C99 mode. */
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if (!TARGET_C99_FUNCTIONS)
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break;
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if (outprec < TYPE_PRECISION (long_integer_type_node)
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|| (outprec == TYPE_PRECISION (long_integer_type_node)
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&& !TYPE_UNSIGNED (type)))
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fn = mathfn_built_in (s_intype, BUILT_IN_LCEIL);
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else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
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&& !TYPE_UNSIGNED (type))
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fn = mathfn_built_in (s_intype, BUILT_IN_LLCEIL);
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break;
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CASE_FLT_FN (BUILT_IN_FLOOR):
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/* Only convert in ISO C99 mode. */
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if (!TARGET_C99_FUNCTIONS)
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break;
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if (outprec < TYPE_PRECISION (long_integer_type_node)
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|| (outprec == TYPE_PRECISION (long_integer_type_node)
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&& !TYPE_UNSIGNED (type)))
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fn = mathfn_built_in (s_intype, BUILT_IN_LFLOOR);
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else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
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&& !TYPE_UNSIGNED (type))
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fn = mathfn_built_in (s_intype, BUILT_IN_LLFLOOR);
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break;
|
|
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|
CASE_FLT_FN (BUILT_IN_ROUND):
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if (outprec < TYPE_PRECISION (long_integer_type_node)
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|| (outprec == TYPE_PRECISION (long_integer_type_node)
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&& !TYPE_UNSIGNED (type)))
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|
fn = mathfn_built_in (s_intype, BUILT_IN_LROUND);
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else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
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&& !TYPE_UNSIGNED (type))
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fn = mathfn_built_in (s_intype, BUILT_IN_LLROUND);
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break;
|
|
|
|
CASE_FLT_FN (BUILT_IN_NEARBYINT):
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|
/* Only convert nearbyint* if we can ignore math exceptions. */
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|
if (flag_trapping_math)
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|
break;
|
|
/* ... Fall through ... */
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|
CASE_FLT_FN (BUILT_IN_RINT):
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|
if (outprec < TYPE_PRECISION (long_integer_type_node)
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|
|| (outprec == TYPE_PRECISION (long_integer_type_node)
|
|
&& !TYPE_UNSIGNED (type)))
|
|
fn = mathfn_built_in (s_intype, BUILT_IN_LRINT);
|
|
else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
|
|
&& !TYPE_UNSIGNED (type))
|
|
fn = mathfn_built_in (s_intype, BUILT_IN_LLRINT);
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|
break;
|
|
|
|
CASE_FLT_FN (BUILT_IN_TRUNC):
|
|
{
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|
tree arglist = TREE_OPERAND (s_expr, 1);
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|
return convert_to_integer (type, TREE_VALUE (arglist));
|
|
}
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
if (fn)
|
|
{
|
|
tree arglist = TREE_OPERAND (s_expr, 1);
|
|
tree newexpr = build_function_call_expr (fn, arglist);
|
|
return convert_to_integer (type, newexpr);
|
|
}
|
|
}
|
|
|
|
switch (TREE_CODE (intype))
|
|
{
|
|
case POINTER_TYPE:
|
|
case REFERENCE_TYPE:
|
|
if (integer_zerop (expr))
|
|
return build_int_cst (type, 0);
|
|
|
|
/* Convert to an unsigned integer of the correct width first,
|
|
and from there widen/truncate to the required type. */
|
|
expr = fold_build1 (CONVERT_EXPR,
|
|
lang_hooks.types.type_for_size (POINTER_SIZE, 0),
|
|
expr);
|
|
return fold_convert (type, expr);
|
|
|
|
case INTEGER_TYPE:
|
|
case ENUMERAL_TYPE:
|
|
case BOOLEAN_TYPE:
|
|
/* If this is a logical operation, which just returns 0 or 1, we can
|
|
change the type of the expression. */
|
|
|
|
if (TREE_CODE_CLASS (ex_form) == tcc_comparison)
|
|
{
|
|
expr = copy_node (expr);
|
|
TREE_TYPE (expr) = type;
|
|
return expr;
|
|
}
|
|
|
|
/* If we are widening the type, put in an explicit conversion.
|
|
Similarly if we are not changing the width. After this, we know
|
|
we are truncating EXPR. */
|
|
|
|
else if (outprec >= inprec)
|
|
{
|
|
enum tree_code code;
|
|
tree tem;
|
|
|
|
/* If the precision of the EXPR's type is K bits and the
|
|
destination mode has more bits, and the sign is changing,
|
|
it is not safe to use a NOP_EXPR. For example, suppose
|
|
that EXPR's type is a 3-bit unsigned integer type, the
|
|
TYPE is a 3-bit signed integer type, and the machine mode
|
|
for the types is 8-bit QImode. In that case, the
|
|
conversion necessitates an explicit sign-extension. In
|
|
the signed-to-unsigned case the high-order bits have to
|
|
be cleared. */
|
|
if (TYPE_UNSIGNED (type) != TYPE_UNSIGNED (TREE_TYPE (expr))
|
|
&& (TYPE_PRECISION (TREE_TYPE (expr))
|
|
!= GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)))))
|
|
code = CONVERT_EXPR;
|
|
else
|
|
code = NOP_EXPR;
|
|
|
|
tem = fold_unary (code, type, expr);
|
|
if (tem)
|
|
return tem;
|
|
|
|
tem = build1 (code, type, expr);
|
|
TREE_NO_WARNING (tem) = 1;
|
|
return tem;
|
|
}
|
|
|
|
/* If TYPE is an enumeral type or a type with a precision less
|
|
than the number of bits in its mode, do the conversion to the
|
|
type corresponding to its mode, then do a nop conversion
|
|
to TYPE. */
|
|
else if (TREE_CODE (type) == ENUMERAL_TYPE
|
|
|| outprec != GET_MODE_BITSIZE (TYPE_MODE (type)))
|
|
return build1 (NOP_EXPR, type,
|
|
convert (lang_hooks.types.type_for_mode
|
|
(TYPE_MODE (type), TYPE_UNSIGNED (type)),
|
|
expr));
|
|
|
|
/* Here detect when we can distribute the truncation down past some
|
|
arithmetic. For example, if adding two longs and converting to an
|
|
int, we can equally well convert both to ints and then add.
|
|
For the operations handled here, such truncation distribution
|
|
is always safe.
|
|
It is desirable in these cases:
|
|
1) when truncating down to full-word from a larger size
|
|
2) when truncating takes no work.
|
|
3) when at least one operand of the arithmetic has been extended
|
|
(as by C's default conversions). In this case we need two conversions
|
|
if we do the arithmetic as already requested, so we might as well
|
|
truncate both and then combine. Perhaps that way we need only one.
|
|
|
|
Note that in general we cannot do the arithmetic in a type
|
|
shorter than the desired result of conversion, even if the operands
|
|
are both extended from a shorter type, because they might overflow
|
|
if combined in that type. The exceptions to this--the times when
|
|
two narrow values can be combined in their narrow type even to
|
|
make a wider result--are handled by "shorten" in build_binary_op. */
|
|
|
|
switch (ex_form)
|
|
{
|
|
case RSHIFT_EXPR:
|
|
/* We can pass truncation down through right shifting
|
|
when the shift count is a nonpositive constant. */
|
|
if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
|
|
&& tree_int_cst_sgn (TREE_OPERAND (expr, 1)) <= 0)
|
|
goto trunc1;
|
|
break;
|
|
|
|
case LSHIFT_EXPR:
|
|
/* We can pass truncation down through left shifting
|
|
when the shift count is a nonnegative constant and
|
|
the target type is unsigned. */
|
|
if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
|
|
&& tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0
|
|
&& TYPE_UNSIGNED (type)
|
|
&& TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
|
|
{
|
|
/* If shift count is less than the width of the truncated type,
|
|
really shift. */
|
|
if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type)))
|
|
/* In this case, shifting is like multiplication. */
|
|
goto trunc1;
|
|
else
|
|
{
|
|
/* If it is >= that width, result is zero.
|
|
Handling this with trunc1 would give the wrong result:
|
|
(int) ((long long) a << 32) is well defined (as 0)
|
|
but (int) a << 32 is undefined and would get a
|
|
warning. */
|
|
|
|
tree t = build_int_cst (type, 0);
|
|
|
|
/* If the original expression had side-effects, we must
|
|
preserve it. */
|
|
if (TREE_SIDE_EFFECTS (expr))
|
|
return build2 (COMPOUND_EXPR, type, expr, t);
|
|
else
|
|
return t;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case MAX_EXPR:
|
|
case MIN_EXPR:
|
|
case MULT_EXPR:
|
|
{
|
|
tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
|
|
tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
|
|
|
|
/* Don't distribute unless the output precision is at least as big
|
|
as the actual inputs. Otherwise, the comparison of the
|
|
truncated values will be wrong. */
|
|
if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
|
|
&& outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
|
|
/* If signedness of arg0 and arg1 don't match,
|
|
we can't necessarily find a type to compare them in. */
|
|
&& (TYPE_UNSIGNED (TREE_TYPE (arg0))
|
|
== TYPE_UNSIGNED (TREE_TYPE (arg1))))
|
|
goto trunc1;
|
|
break;
|
|
}
|
|
|
|
case PLUS_EXPR:
|
|
case MINUS_EXPR:
|
|
case BIT_AND_EXPR:
|
|
case BIT_IOR_EXPR:
|
|
case BIT_XOR_EXPR:
|
|
trunc1:
|
|
{
|
|
tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
|
|
tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
|
|
|
|
if (outprec >= BITS_PER_WORD
|
|
|| TRULY_NOOP_TRUNCATION (outprec, inprec)
|
|
|| inprec > TYPE_PRECISION (TREE_TYPE (arg0))
|
|
|| inprec > TYPE_PRECISION (TREE_TYPE (arg1)))
|
|
{
|
|
/* Do the arithmetic in type TYPEX,
|
|
then convert result to TYPE. */
|
|
tree typex = type;
|
|
|
|
/* Can't do arithmetic in enumeral types
|
|
so use an integer type that will hold the values. */
|
|
if (TREE_CODE (typex) == ENUMERAL_TYPE)
|
|
typex = lang_hooks.types.type_for_size
|
|
(TYPE_PRECISION (typex), TYPE_UNSIGNED (typex));
|
|
|
|
/* But now perhaps TYPEX is as wide as INPREC.
|
|
In that case, do nothing special here.
|
|
(Otherwise would recurse infinitely in convert. */
|
|
if (TYPE_PRECISION (typex) != inprec)
|
|
{
|
|
/* Don't do unsigned arithmetic where signed was wanted,
|
|
or vice versa.
|
|
Exception: if both of the original operands were
|
|
unsigned then we can safely do the work as unsigned.
|
|
Exception: shift operations take their type solely
|
|
from the first argument.
|
|
Exception: the LSHIFT_EXPR case above requires that
|
|
we perform this operation unsigned lest we produce
|
|
signed-overflow undefinedness.
|
|
And we may need to do it as unsigned
|
|
if we truncate to the original size. */
|
|
if (TYPE_UNSIGNED (TREE_TYPE (expr))
|
|
|| (TYPE_UNSIGNED (TREE_TYPE (arg0))
|
|
&& (TYPE_UNSIGNED (TREE_TYPE (arg1))
|
|
|| ex_form == LSHIFT_EXPR
|
|
|| ex_form == RSHIFT_EXPR
|
|
|| ex_form == LROTATE_EXPR
|
|
|| ex_form == RROTATE_EXPR))
|
|
|| ex_form == LSHIFT_EXPR
|
|
/* If we have !flag_wrapv, and either ARG0 or
|
|
ARG1 is of a signed type, we have to do
|
|
PLUS_EXPR or MINUS_EXPR in an unsigned
|
|
type. Otherwise, we would introduce
|
|
signed-overflow undefinedness. */
|
|
|| ((!TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
|
|
|| !TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1)))
|
|
&& (ex_form == PLUS_EXPR
|
|
|| ex_form == MINUS_EXPR)))
|
|
typex = lang_hooks.types.unsigned_type (typex);
|
|
else
|
|
typex = lang_hooks.types.signed_type (typex);
|
|
return convert (type,
|
|
fold_build2 (ex_form, typex,
|
|
convert (typex, arg0),
|
|
convert (typex, arg1)));
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
|
|
case NEGATE_EXPR:
|
|
case BIT_NOT_EXPR:
|
|
/* This is not correct for ABS_EXPR,
|
|
since we must test the sign before truncation. */
|
|
{
|
|
tree typex;
|
|
|
|
/* Don't do unsigned arithmetic where signed was wanted,
|
|
or vice versa. */
|
|
if (TYPE_UNSIGNED (TREE_TYPE (expr)))
|
|
typex = lang_hooks.types.unsigned_type (type);
|
|
else
|
|
typex = lang_hooks.types.signed_type (type);
|
|
return convert (type,
|
|
fold_build1 (ex_form, typex,
|
|
convert (typex,
|
|
TREE_OPERAND (expr, 0))));
|
|
}
|
|
|
|
case NOP_EXPR:
|
|
/* Don't introduce a
|
|
"can't convert between vector values of different size" error. */
|
|
if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == VECTOR_TYPE
|
|
&& (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0))))
|
|
!= GET_MODE_SIZE (TYPE_MODE (type))))
|
|
break;
|
|
/* If truncating after truncating, might as well do all at once.
|
|
If truncating after extending, we may get rid of wasted work. */
|
|
return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type));
|
|
|
|
case COND_EXPR:
|
|
/* It is sometimes worthwhile to push the narrowing down through
|
|
the conditional and never loses. */
|
|
return fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
|
|
convert (type, TREE_OPERAND (expr, 1)),
|
|
convert (type, TREE_OPERAND (expr, 2)));
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return build1 (CONVERT_EXPR, type, expr);
|
|
|
|
case REAL_TYPE:
|
|
return build1 (FIX_TRUNC_EXPR, type, expr);
|
|
|
|
case COMPLEX_TYPE:
|
|
return convert (type,
|
|
fold_build1 (REALPART_EXPR,
|
|
TREE_TYPE (TREE_TYPE (expr)), expr));
|
|
|
|
case VECTOR_TYPE:
|
|
if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
|
|
{
|
|
error ("can't convert between vector values of different size");
|
|
return error_mark_node;
|
|
}
|
|
return build1 (VIEW_CONVERT_EXPR, type, expr);
|
|
|
|
default:
|
|
error ("aggregate value used where an integer was expected");
|
|
return convert (type, integer_zero_node);
|
|
}
|
|
}
|
|
|
|
/* Convert EXPR to the complex type TYPE in the usual ways. */
|
|
|
|
tree
|
|
convert_to_complex (tree type, tree expr)
|
|
{
|
|
tree subtype = TREE_TYPE (type);
|
|
|
|
switch (TREE_CODE (TREE_TYPE (expr)))
|
|
{
|
|
case REAL_TYPE:
|
|
case INTEGER_TYPE:
|
|
case ENUMERAL_TYPE:
|
|
case BOOLEAN_TYPE:
|
|
return build2 (COMPLEX_EXPR, type, convert (subtype, expr),
|
|
convert (subtype, integer_zero_node));
|
|
|
|
case COMPLEX_TYPE:
|
|
{
|
|
tree elt_type = TREE_TYPE (TREE_TYPE (expr));
|
|
|
|
if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
|
|
return expr;
|
|
else if (TREE_CODE (expr) == COMPLEX_EXPR)
|
|
return fold_build2 (COMPLEX_EXPR, type,
|
|
convert (subtype, TREE_OPERAND (expr, 0)),
|
|
convert (subtype, TREE_OPERAND (expr, 1)));
|
|
else
|
|
{
|
|
expr = save_expr (expr);
|
|
return
|
|
fold_build2 (COMPLEX_EXPR, type,
|
|
convert (subtype,
|
|
fold_build1 (REALPART_EXPR,
|
|
TREE_TYPE (TREE_TYPE (expr)),
|
|
expr)),
|
|
convert (subtype,
|
|
fold_build1 (IMAGPART_EXPR,
|
|
TREE_TYPE (TREE_TYPE (expr)),
|
|
expr)));
|
|
}
|
|
}
|
|
|
|
case POINTER_TYPE:
|
|
case REFERENCE_TYPE:
|
|
error ("pointer value used where a complex was expected");
|
|
return convert_to_complex (type, integer_zero_node);
|
|
|
|
default:
|
|
error ("aggregate value used where a complex was expected");
|
|
return convert_to_complex (type, integer_zero_node);
|
|
}
|
|
}
|
|
|
|
/* Convert EXPR to the vector type TYPE in the usual ways. */
|
|
|
|
tree
|
|
convert_to_vector (tree type, tree expr)
|
|
{
|
|
switch (TREE_CODE (TREE_TYPE (expr)))
|
|
{
|
|
case INTEGER_TYPE:
|
|
case VECTOR_TYPE:
|
|
if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
|
|
{
|
|
error ("can't convert between vector values of different size");
|
|
return error_mark_node;
|
|
}
|
|
return build1 (VIEW_CONVERT_EXPR, type, expr);
|
|
|
|
default:
|
|
error ("can't convert value to a vector");
|
|
return error_mark_node;
|
|
}
|
|
}
|