1 /* This file contains subroutine used by the C front-end to construct GENERIC. 2 Copyright (C) 2000-2017 Free Software Foundation, Inc. 3 Written by Benjamin Chelf (chelf@codesourcery.com). 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 3, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #include "config.h" 22 #include "system.h" 23 #include "coretypes.h" 24 #include "c-common.h" 25 #include "tree-iterator.h" 26 27 /* Create an empty statement tree rooted at T. */ 28 29 tree 30 push_stmt_list (void) 31 { 32 tree t; 33 t = alloc_stmt_list (); 34 vec_safe_push (stmt_list_stack, t); 35 return t; 36 } 37 38 /* Finish the statement tree rooted at T. */ 39 40 tree 41 pop_stmt_list (tree t) 42 { 43 tree u = NULL_TREE; 44 45 /* Pop statement lists until we reach the target level. The extra 46 nestings will be due to outstanding cleanups. */ 47 while (1) 48 { 49 u = stmt_list_stack->pop (); 50 if (!stmt_list_stack->is_empty ()) 51 { 52 tree x = stmt_list_stack->last (); 53 STATEMENT_LIST_HAS_LABEL (x) |= STATEMENT_LIST_HAS_LABEL (u); 54 } 55 if (t == u) 56 break; 57 } 58 59 gcc_assert (u != NULL_TREE); 60 61 /* If the statement list is completely empty, just return it. This is 62 just as good small as build_empty_stmt, with the advantage that 63 statement lists are merged when they appended to one another. So 64 using the STATEMENT_LIST avoids pathological buildup of EMPTY_STMT_P 65 statements. */ 66 if (TREE_SIDE_EFFECTS (t)) 67 { 68 tree_stmt_iterator i = tsi_start (t); 69 70 /* If the statement list contained exactly one statement, then 71 extract it immediately. */ 72 if (tsi_one_before_end_p (i)) 73 { 74 u = tsi_stmt (i); 75 tsi_delink (&i); 76 free_stmt_list (t); 77 t = u; 78 } 79 } 80 81 return t; 82 } 83 84 /* Build a generic statement based on the given type of node and 85 arguments. Similar to `build_nt', except that we set 86 EXPR_LOCATION to LOC. */ 87 /* ??? This should be obsolete with the lineno_stmt productions 88 in the grammar. */ 89 90 tree 91 build_stmt (location_t loc, enum tree_code code, ...) 92 { 93 tree ret; 94 int length, i; 95 va_list p; 96 bool side_effects; 97 98 /* This function cannot be used to construct variably-sized nodes. */ 99 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp); 100 101 va_start (p, code); 102 103 ret = make_node (code); 104 TREE_TYPE (ret) = void_type_node; 105 length = TREE_CODE_LENGTH (code); 106 SET_EXPR_LOCATION (ret, loc); 107 108 /* TREE_SIDE_EFFECTS will already be set for statements with 109 implicit side effects. Here we make sure it is set for other 110 expressions by checking whether the parameters have side 111 effects. */ 112 113 side_effects = false; 114 for (i = 0; i < length; i++) 115 { 116 tree t = va_arg (p, tree); 117 if (t && !TYPE_P (t)) 118 side_effects |= TREE_SIDE_EFFECTS (t); 119 TREE_OPERAND (ret, i) = t; 120 } 121 122 TREE_SIDE_EFFECTS (ret) |= side_effects; 123 124 va_end (p); 125 return ret; 126 } 127 128 /* Build a REALPART_EXPR or IMAGPART_EXPR, according to CODE, from ARG. */ 129 130 tree 131 build_real_imag_expr (location_t location, enum tree_code code, tree arg) 132 { 133 tree ret; 134 tree arg_type = TREE_TYPE (arg); 135 136 gcc_assert (code == REALPART_EXPR || code == IMAGPART_EXPR); 137 138 if (TREE_CODE (arg_type) == COMPLEX_TYPE) 139 { 140 ret = build1 (code, TREE_TYPE (TREE_TYPE (arg)), arg); 141 SET_EXPR_LOCATION (ret, location); 142 } 143 else if (INTEGRAL_TYPE_P (arg_type) || SCALAR_FLOAT_TYPE_P (arg_type)) 144 { 145 ret = (code == REALPART_EXPR 146 ? arg 147 : omit_one_operand_loc (location, arg_type, 148 integer_zero_node, arg)); 149 } 150 else 151 { 152 error_at (location, "wrong type argument to %s", 153 code == REALPART_EXPR ? "__real" : "__imag"); 154 ret = error_mark_node; 155 } 156 157 return ret; 158 } 159