expr.c revision 90075
1/* Convert language-specific tree expression to rtl instructions, 2 for GNU compiler. 3 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 4 2000, 2001 Free Software Foundation, Inc. 5 6This file is part of GNU CC. 7 8GNU CC is free software; you can redistribute it and/or modify 9it under the terms of the GNU General Public License as published by 10the Free Software Foundation; either version 2, or (at your option) 11any later version. 12 13GNU CC is distributed in the hope that it will be useful, 14but WITHOUT ANY WARRANTY; without even the implied warranty of 15MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16GNU General Public License for more details. 17 18You should have received a copy of the GNU General Public License 19along with GNU CC; see the file COPYING. If not, write to 20the Free Software Foundation, 59 Temple Place - Suite 330, 21Boston, MA 02111-1307, USA. */ 22 23 24#include "config.h" 25#include "system.h" 26#include "rtl.h" 27#include "tree.h" 28#include "flags.h" 29#include "expr.h" 30#include "cp-tree.h" 31#include "toplev.h" 32#include "except.h" 33#include "tm_p.h" 34 35static rtx cplus_expand_expr PARAMS ((tree, rtx, enum machine_mode, 36 enum expand_modifier)); 37 38/* Hook used by output_constant to expand language-specific 39 constants. */ 40 41tree 42cplus_expand_constant (cst) 43 tree cst; 44{ 45 switch (TREE_CODE (cst)) 46 { 47 case PTRMEM_CST: 48 { 49 tree type = TREE_TYPE (cst); 50 tree member; 51 52 /* Find the member. */ 53 member = PTRMEM_CST_MEMBER (cst); 54 55 if (TREE_CODE (member) == FIELD_DECL) 56 { 57 /* Find the offset for the field. */ 58 tree offset = byte_position (member); 59 cst = fold (build1 (NOP_EXPR, type, offset)); 60 } 61 else 62 { 63 tree delta; 64 tree pfn; 65 66 expand_ptrmemfunc_cst (cst, &delta, &pfn); 67 cst = build_ptrmemfunc1 (type, delta, pfn); 68 } 69 } 70 break; 71 72 default: 73 /* There's nothing to do. */ 74 break; 75 } 76 77 return cst; 78} 79 80/* Hook used by expand_expr to expand language-specific tree codes. */ 81 82static rtx 83cplus_expand_expr (exp, target, tmode, modifier) 84 tree exp; 85 rtx target; 86 enum machine_mode tmode; 87 enum expand_modifier modifier; 88{ 89 tree type = TREE_TYPE (exp); 90 register enum machine_mode mode = TYPE_MODE (type); 91 register enum tree_code code = TREE_CODE (exp); 92 rtx ret; 93 94 /* No sense saving up arithmetic to be done 95 if it's all in the wrong mode to form part of an address. 96 And force_operand won't know whether to sign-extend or zero-extend. */ 97 98 if (mode != Pmode && modifier == EXPAND_SUM) 99 modifier = EXPAND_NORMAL; 100 101 switch (code) 102 { 103 case PTRMEM_CST: 104 return expand_expr (cplus_expand_constant (exp), 105 target, tmode, modifier); 106 107 case OFFSET_REF: 108 /* Offset refs should not make it through to here. */ 109 abort (); 110 return const0_rtx; 111 112 case THROW_EXPR: 113 expand_expr (TREE_OPERAND (exp, 0), const0_rtx, VOIDmode, 0); 114 return NULL; 115 116 case MUST_NOT_THROW_EXPR: 117 expand_eh_region_start (); 118 ret = expand_expr (TREE_OPERAND (exp, 0), target, tmode, modifier); 119 expand_eh_region_end_must_not_throw (build_call (terminate_node, 0)); 120 return ret; 121 122 case EMPTY_CLASS_EXPR: 123 /* We don't need to generate any code for an empty class. */ 124 return const0_rtx; 125 126 default: 127 return c_expand_expr (exp, target, tmode, modifier); 128 } 129 abort (); 130 /* NOTREACHED */ 131 return NULL; 132} 133 134void 135init_cplus_expand () 136{ 137 lang_expand_expr = cplus_expand_expr; 138} 139 140int 141extract_init (decl, init) 142 tree decl ATTRIBUTE_UNUSED, init ATTRIBUTE_UNUSED; 143{ 144 return 0; 145} 146 147