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0
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1 /* C-compiler utilities for types and variables storage layout
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2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998,
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3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
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4 Free Software Foundation, Inc.
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5
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6 This file is part of GCC.
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7
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8 GCC is free software; you can redistribute it and/or modify it under
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9 the terms of the GNU General Public License as published by the Free
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10 Software Foundation; either version 3, or (at your option) any later
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11 version.
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12
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13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
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15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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16 for more details.
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17
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18 You should have received a copy of the GNU General Public License
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19 along with GCC; see the file COPYING3. If not see
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20 <http://www.gnu.org/licenses/>. */
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21
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22
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23 #include "config.h"
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24 #include "system.h"
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25 #include "coretypes.h"
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26 #include "tm.h"
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27 #include "tree.h"
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28 #include "rtl.h"
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29 #include "tm_p.h"
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30 #include "flags.h"
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31 #include "function.h"
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32 #include "expr.h"
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33 #include "output.h"
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34 #include "toplev.h"
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35 #include "ggc.h"
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36 #include "target.h"
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37 #include "langhooks.h"
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38 #include "regs.h"
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39 #include "params.h"
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40
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41 /* Data type for the expressions representing sizes of data types.
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42 It is the first integer type laid out. */
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43 tree sizetype_tab[(int) TYPE_KIND_LAST];
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44
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45 /* If nonzero, this is an upper limit on alignment of structure fields.
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46 The value is measured in bits. */
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47 unsigned int maximum_field_alignment = TARGET_DEFAULT_PACK_STRUCT * BITS_PER_UNIT;
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48 /* ... and its original value in bytes, specified via -fpack-struct=<value>. */
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49 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT;
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50
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51 /* Nonzero if all REFERENCE_TYPEs are internal and hence should be
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52 allocated in Pmode, not ptr_mode. Set only by internal_reference_types
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53 called only by a front end. */
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54 static int reference_types_internal = 0;
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55
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56 static void finalize_record_size (record_layout_info);
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57 static void finalize_type_size (tree);
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58 static void place_union_field (record_layout_info, tree);
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59 #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED)
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60 static int excess_unit_span (HOST_WIDE_INT, HOST_WIDE_INT, HOST_WIDE_INT,
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61 HOST_WIDE_INT, tree);
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62 #endif
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63 extern void debug_rli (record_layout_info);
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64
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65 /* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */
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66
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67 static GTY(()) tree pending_sizes;
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68
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69 /* Show that REFERENCE_TYPES are internal and should be Pmode. Called only
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70 by front end. */
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71
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72 void
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73 internal_reference_types (void)
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74 {
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75 reference_types_internal = 1;
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76 }
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77
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78 /* Get a list of all the objects put on the pending sizes list. */
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79
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80 tree
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81 get_pending_sizes (void)
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82 {
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83 tree chain = pending_sizes;
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84
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85 pending_sizes = 0;
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86 return chain;
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87 }
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88
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89 /* Add EXPR to the pending sizes list. */
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90
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91 void
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92 put_pending_size (tree expr)
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93 {
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94 /* Strip any simple arithmetic from EXPR to see if it has an underlying
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95 SAVE_EXPR. */
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96 expr = skip_simple_arithmetic (expr);
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97
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98 if (TREE_CODE (expr) == SAVE_EXPR)
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99 pending_sizes = tree_cons (NULL_TREE, expr, pending_sizes);
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100 }
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101
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102 /* Put a chain of objects into the pending sizes list, which must be
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103 empty. */
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104
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105 void
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106 put_pending_sizes (tree chain)
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107 {
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108 gcc_assert (!pending_sizes);
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109 pending_sizes = chain;
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110 }
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111
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112 /* Given a size SIZE that may not be a constant, return a SAVE_EXPR
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113 to serve as the actual size-expression for a type or decl. */
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114
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115 tree
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116 variable_size (tree size)
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117 {
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118 tree save;
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119
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120 /* If the language-processor is to take responsibility for variable-sized
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121 items (e.g., languages which have elaboration procedures like Ada),
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122 just return SIZE unchanged. Likewise for self-referential sizes and
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123 constant sizes. */
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124 if (TREE_CONSTANT (size)
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125 || lang_hooks.decls.global_bindings_p () < 0
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126 || CONTAINS_PLACEHOLDER_P (size))
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127 return size;
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128
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129 size = save_expr (size);
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130
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131 /* If an array with a variable number of elements is declared, and
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132 the elements require destruction, we will emit a cleanup for the
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133 array. That cleanup is run both on normal exit from the block
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134 and in the exception-handler for the block. Normally, when code
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135 is used in both ordinary code and in an exception handler it is
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136 `unsaved', i.e., all SAVE_EXPRs are recalculated. However, we do
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137 not wish to do that here; the array-size is the same in both
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138 places. */
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139 save = skip_simple_arithmetic (size);
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140
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141 if (cfun && cfun->dont_save_pending_sizes_p)
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142 /* The front-end doesn't want us to keep a list of the expressions
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143 that determine sizes for variable size objects. Trust it. */
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144 return size;
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145
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146 if (lang_hooks.decls.global_bindings_p ())
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147 {
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148 if (TREE_CONSTANT (size))
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149 error ("type size can%'t be explicitly evaluated");
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150 else
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151 error ("variable-size type declared outside of any function");
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152
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153 return size_one_node;
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154 }
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155
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156 put_pending_size (save);
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157
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158 return size;
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159 }
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160
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161 #ifndef MAX_FIXED_MODE_SIZE
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162 #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode)
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163 #endif
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164
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165 /* Return the machine mode to use for a nonscalar of SIZE bits. The
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166 mode must be in class MCLASS, and have exactly that many value bits;
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167 it may have padding as well. If LIMIT is nonzero, modes of wider
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168 than MAX_FIXED_MODE_SIZE will not be used. */
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169
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170 enum machine_mode
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171 mode_for_size (unsigned int size, enum mode_class mclass, int limit)
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172 {
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173 enum machine_mode mode;
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174
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175 if (limit && size > MAX_FIXED_MODE_SIZE)
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176 return BLKmode;
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177
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178 /* Get the first mode which has this size, in the specified class. */
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179 for (mode = GET_CLASS_NARROWEST_MODE (mclass); mode != VOIDmode;
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180 mode = GET_MODE_WIDER_MODE (mode))
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181 if (GET_MODE_PRECISION (mode) == size)
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182 return mode;
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183
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184 return BLKmode;
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185 }
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186
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187 /* Similar, except passed a tree node. */
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188
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189 enum machine_mode
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190 mode_for_size_tree (const_tree size, enum mode_class mclass, int limit)
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191 {
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192 unsigned HOST_WIDE_INT uhwi;
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193 unsigned int ui;
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194
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195 if (!host_integerp (size, 1))
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196 return BLKmode;
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197 uhwi = tree_low_cst (size, 1);
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198 ui = uhwi;
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199 if (uhwi != ui)
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200 return BLKmode;
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201 return mode_for_size (ui, mclass, limit);
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202 }
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203
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204 /* Similar, but never return BLKmode; return the narrowest mode that
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205 contains at least the requested number of value bits. */
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206
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207 enum machine_mode
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208 smallest_mode_for_size (unsigned int size, enum mode_class mclass)
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209 {
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210 enum machine_mode mode;
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211
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212 /* Get the first mode which has at least this size, in the
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213 specified class. */
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214 for (mode = GET_CLASS_NARROWEST_MODE (mclass); mode != VOIDmode;
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215 mode = GET_MODE_WIDER_MODE (mode))
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216 if (GET_MODE_PRECISION (mode) >= size)
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217 return mode;
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218
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219 gcc_unreachable ();
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220 }
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221
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222 /* Find an integer mode of the exact same size, or BLKmode on failure. */
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223
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224 enum machine_mode
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225 int_mode_for_mode (enum machine_mode mode)
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226 {
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227 switch (GET_MODE_CLASS (mode))
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228 {
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229 case MODE_INT:
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230 case MODE_PARTIAL_INT:
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231 break;
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232
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233 case MODE_COMPLEX_INT:
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234 case MODE_COMPLEX_FLOAT:
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235 case MODE_FLOAT:
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236 case MODE_DECIMAL_FLOAT:
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237 case MODE_VECTOR_INT:
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238 case MODE_VECTOR_FLOAT:
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239 case MODE_FRACT:
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240 case MODE_ACCUM:
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241 case MODE_UFRACT:
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242 case MODE_UACCUM:
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243 case MODE_VECTOR_FRACT:
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244 case MODE_VECTOR_ACCUM:
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245 case MODE_VECTOR_UFRACT:
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246 case MODE_VECTOR_UACCUM:
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247 mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0);
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248 break;
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249
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250 case MODE_RANDOM:
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251 if (mode == BLKmode)
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252 break;
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253
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254 /* ... fall through ... */
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255
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256 case MODE_CC:
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257 default:
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258 gcc_unreachable ();
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259 }
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260
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261 return mode;
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262 }
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263
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264 /* Return the alignment of MODE. This will be bounded by 1 and
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265 BIGGEST_ALIGNMENT. */
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266
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267 unsigned int
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268 get_mode_alignment (enum machine_mode mode)
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269 {
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270 return MIN (BIGGEST_ALIGNMENT, MAX (1, mode_base_align[mode]*BITS_PER_UNIT));
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271 }
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272
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273
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274 /* Subroutine of layout_decl: Force alignment required for the data type.
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275 But if the decl itself wants greater alignment, don't override that. */
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276
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277 static inline void
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278 do_type_align (tree type, tree decl)
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279 {
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280 if (TYPE_ALIGN (type) > DECL_ALIGN (decl))
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281 {
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282 DECL_ALIGN (decl) = TYPE_ALIGN (type);
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283 if (TREE_CODE (decl) == FIELD_DECL)
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284 DECL_USER_ALIGN (decl) = TYPE_USER_ALIGN (type);
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285 }
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286 }
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287
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288 /* Set the size, mode and alignment of a ..._DECL node.
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289 TYPE_DECL does need this for C++.
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290 Note that LABEL_DECL and CONST_DECL nodes do not need this,
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291 and FUNCTION_DECL nodes have them set up in a special (and simple) way.
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292 Don't call layout_decl for them.
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293
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294 KNOWN_ALIGN is the amount of alignment we can assume this
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295 decl has with no special effort. It is relevant only for FIELD_DECLs
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296 and depends on the previous fields.
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297 All that matters about KNOWN_ALIGN is which powers of 2 divide it.
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298 If KNOWN_ALIGN is 0, it means, "as much alignment as you like":
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299 the record will be aligned to suit. */
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300
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301 void
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302 layout_decl (tree decl, unsigned int known_align)
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303 {
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304 tree type = TREE_TYPE (decl);
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305 enum tree_code code = TREE_CODE (decl);
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306 rtx rtl = NULL_RTX;
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307
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308 if (code == CONST_DECL)
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309 return;
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310
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311 gcc_assert (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL
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312 || code == TYPE_DECL ||code == FIELD_DECL);
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313
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314 rtl = DECL_RTL_IF_SET (decl);
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315
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316 if (type == error_mark_node)
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317 type = void_type_node;
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318
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319 /* Usually the size and mode come from the data type without change,
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320 however, the front-end may set the explicit width of the field, so its
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321 size may not be the same as the size of its type. This happens with
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322 bitfields, of course (an `int' bitfield may be only 2 bits, say), but it
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323 also happens with other fields. For example, the C++ front-end creates
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324 zero-sized fields corresponding to empty base classes, and depends on
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325 layout_type setting DECL_FIELD_BITPOS correctly for the field. Set the
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326 size in bytes from the size in bits. If we have already set the mode,
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327 don't set it again since we can be called twice for FIELD_DECLs. */
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328
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329 DECL_UNSIGNED (decl) = TYPE_UNSIGNED (type);
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330 if (DECL_MODE (decl) == VOIDmode)
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331 DECL_MODE (decl) = TYPE_MODE (type);
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332
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333 if (DECL_SIZE (decl) == 0)
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334 {
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335 DECL_SIZE (decl) = TYPE_SIZE (type);
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336 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type);
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337 }
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338 else if (DECL_SIZE_UNIT (decl) == 0)
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339 DECL_SIZE_UNIT (decl)
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340 = fold_convert (sizetype, size_binop (CEIL_DIV_EXPR, DECL_SIZE (decl),
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341 bitsize_unit_node));
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342
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343 if (code != FIELD_DECL)
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344 /* For non-fields, update the alignment from the type. */
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345 do_type_align (type, decl);
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346 else
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347 /* For fields, it's a bit more complicated... */
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348 {
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349 bool old_user_align = DECL_USER_ALIGN (decl);
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350 bool zero_bitfield = false;
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351 bool packed_p = DECL_PACKED (decl);
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352 unsigned int mfa;
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353
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354 if (DECL_BIT_FIELD (decl))
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355 {
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356 DECL_BIT_FIELD_TYPE (decl) = type;
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357
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358 /* A zero-length bit-field affects the alignment of the next
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359 field. In essence such bit-fields are not influenced by
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360 any packing due to #pragma pack or attribute packed. */
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361 if (integer_zerop (DECL_SIZE (decl))
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362 && ! targetm.ms_bitfield_layout_p (DECL_FIELD_CONTEXT (decl)))
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363 {
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364 zero_bitfield = true;
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365 packed_p = false;
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366 #ifdef PCC_BITFIELD_TYPE_MATTERS
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367 if (PCC_BITFIELD_TYPE_MATTERS)
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368 do_type_align (type, decl);
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369 else
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370 #endif
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371 {
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372 #ifdef EMPTY_FIELD_BOUNDARY
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373 if (EMPTY_FIELD_BOUNDARY > DECL_ALIGN (decl))
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374 {
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375 DECL_ALIGN (decl) = EMPTY_FIELD_BOUNDARY;
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376 DECL_USER_ALIGN (decl) = 0;
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377 }
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378 #endif
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379 }
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380 }
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381
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382 /* See if we can use an ordinary integer mode for a bit-field.
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383 Conditions are: a fixed size that is correct for another mode
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384 and occupying a complete byte or bytes on proper boundary. */
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385 if (TYPE_SIZE (type) != 0
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386 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
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387 && GET_MODE_CLASS (TYPE_MODE (type)) == MODE_INT)
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388 {
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389 enum machine_mode xmode
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390 = mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1);
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391 unsigned int xalign = GET_MODE_ALIGNMENT (xmode);
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392
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393 if (xmode != BLKmode
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394 && !(xalign > BITS_PER_UNIT && DECL_PACKED (decl))
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395 && (known_align == 0 || known_align >= xalign))
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396 {
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397 DECL_ALIGN (decl) = MAX (xalign, DECL_ALIGN (decl));
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398 DECL_MODE (decl) = xmode;
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399 DECL_BIT_FIELD (decl) = 0;
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400 }
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401 }
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402
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403 /* Turn off DECL_BIT_FIELD if we won't need it set. */
|
|
|
404 if (TYPE_MODE (type) == BLKmode && DECL_MODE (decl) == BLKmode
|
|
|
405 && known_align >= TYPE_ALIGN (type)
|
|
|
406 && DECL_ALIGN (decl) >= TYPE_ALIGN (type))
|
|
|
407 DECL_BIT_FIELD (decl) = 0;
|
|
|
408 }
|
|
|
409 else if (packed_p && DECL_USER_ALIGN (decl))
|
|
|
410 /* Don't touch DECL_ALIGN. For other packed fields, go ahead and
|
|
|
411 round up; we'll reduce it again below. We want packing to
|
|
|
412 supersede USER_ALIGN inherited from the type, but defer to
|
|
|
413 alignment explicitly specified on the field decl. */;
|
|
|
414 else
|
|
|
415 do_type_align (type, decl);
|
|
|
416
|
|
|
417 /* If the field is packed and not explicitly aligned, give it the
|
|
|
418 minimum alignment. Note that do_type_align may set
|
|
|
419 DECL_USER_ALIGN, so we need to check old_user_align instead. */
|
|
|
420 if (packed_p
|
|
|
421 && !old_user_align)
|
|
|
422 DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT);
|
|
|
423
|
|
|
424 if (! packed_p && ! DECL_USER_ALIGN (decl))
|
|
|
425 {
|
|
|
426 /* Some targets (i.e. i386, VMS) limit struct field alignment
|
|
|
427 to a lower boundary than alignment of variables unless
|
|
|
428 it was overridden by attribute aligned. */
|
|
|
429 #ifdef BIGGEST_FIELD_ALIGNMENT
|
|
|
430 DECL_ALIGN (decl)
|
|
|
431 = MIN (DECL_ALIGN (decl), (unsigned) BIGGEST_FIELD_ALIGNMENT);
|
|
|
432 #endif
|
|
|
433 #ifdef ADJUST_FIELD_ALIGN
|
|
|
434 DECL_ALIGN (decl) = ADJUST_FIELD_ALIGN (decl, DECL_ALIGN (decl));
|
|
|
435 #endif
|
|
|
436 }
|
|
|
437
|
|
|
438 if (zero_bitfield)
|
|
|
439 mfa = initial_max_fld_align * BITS_PER_UNIT;
|
|
|
440 else
|
|
|
441 mfa = maximum_field_alignment;
|
|
|
442 /* Should this be controlled by DECL_USER_ALIGN, too? */
|
|
|
443 if (mfa != 0)
|
|
|
444 DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), mfa);
|
|
|
445 }
|
|
|
446
|
|
|
447 /* Evaluate nonconstant size only once, either now or as soon as safe. */
|
|
|
448 if (DECL_SIZE (decl) != 0 && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
|
|
|
449 DECL_SIZE (decl) = variable_size (DECL_SIZE (decl));
|
|
|
450 if (DECL_SIZE_UNIT (decl) != 0
|
|
|
451 && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST)
|
|
|
452 DECL_SIZE_UNIT (decl) = variable_size (DECL_SIZE_UNIT (decl));
|
|
|
453
|
|
|
454 /* If requested, warn about definitions of large data objects. */
|
|
|
455 if (warn_larger_than
|
|
|
456 && (code == VAR_DECL || code == PARM_DECL)
|
|
|
457 && ! DECL_EXTERNAL (decl))
|
|
|
458 {
|
|
|
459 tree size = DECL_SIZE_UNIT (decl);
|
|
|
460
|
|
|
461 if (size != 0 && TREE_CODE (size) == INTEGER_CST
|
|
|
462 && compare_tree_int (size, larger_than_size) > 0)
|
|
|
463 {
|
|
|
464 int size_as_int = TREE_INT_CST_LOW (size);
|
|
|
465
|
|
|
466 if (compare_tree_int (size, size_as_int) == 0)
|
|
|
467 warning (OPT_Wlarger_than_eq, "size of %q+D is %d bytes", decl, size_as_int);
|
|
|
468 else
|
|
|
469 warning (OPT_Wlarger_than_eq, "size of %q+D is larger than %wd bytes",
|
|
|
470 decl, larger_than_size);
|
|
|
471 }
|
|
|
472 }
|
|
|
473
|
|
|
474 /* If the RTL was already set, update its mode and mem attributes. */
|
|
|
475 if (rtl)
|
|
|
476 {
|
|
|
477 PUT_MODE (rtl, DECL_MODE (decl));
|
|
|
478 SET_DECL_RTL (decl, 0);
|
|
|
479 set_mem_attributes (rtl, decl, 1);
|
|
|
480 SET_DECL_RTL (decl, rtl);
|
|
|
481 }
|
|
|
482 }
|
|
|
483
|
|
|
484 /* Given a VAR_DECL, PARM_DECL or RESULT_DECL, clears the results of
|
|
|
485 a previous call to layout_decl and calls it again. */
|
|
|
486
|
|
|
487 void
|
|
|
488 relayout_decl (tree decl)
|
|
|
489 {
|
|
|
490 DECL_SIZE (decl) = DECL_SIZE_UNIT (decl) = 0;
|
|
|
491 DECL_MODE (decl) = VOIDmode;
|
|
|
492 if (!DECL_USER_ALIGN (decl))
|
|
|
493 DECL_ALIGN (decl) = 0;
|
|
|
494 SET_DECL_RTL (decl, 0);
|
|
|
495
|
|
|
496 layout_decl (decl, 0);
|
|
|
497 }
|
|
|
498
|
|
|
499 /* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or
|
|
|
500 QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which
|
|
|
501 is to be passed to all other layout functions for this record. It is the
|
|
|
502 responsibility of the caller to call `free' for the storage returned.
|
|
|
503 Note that garbage collection is not permitted until we finish laying
|
|
|
504 out the record. */
|
|
|
505
|
|
|
506 record_layout_info
|
|
|
507 start_record_layout (tree t)
|
|
|
508 {
|
|
|
509 record_layout_info rli = XNEW (struct record_layout_info_s);
|
|
|
510
|
|
|
511 rli->t = t;
|
|
|
512
|
|
|
513 /* If the type has a minimum specified alignment (via an attribute
|
|
|
514 declaration, for example) use it -- otherwise, start with a
|
|
|
515 one-byte alignment. */
|
|
|
516 rli->record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (t));
|
|
|
517 rli->unpacked_align = rli->record_align;
|
|
|
518 rli->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT);
|
|
|
519
|
|
|
520 #ifdef STRUCTURE_SIZE_BOUNDARY
|
|
|
521 /* Packed structures don't need to have minimum size. */
|
|
|
522 if (! TYPE_PACKED (t))
|
|
|
523 {
|
|
|
524 unsigned tmp;
|
|
|
525
|
|
|
526 /* #pragma pack overrides STRUCTURE_SIZE_BOUNDARY. */
|
|
|
527 tmp = (unsigned) STRUCTURE_SIZE_BOUNDARY;
|
|
|
528 if (maximum_field_alignment != 0)
|
|
|
529 tmp = MIN (tmp, maximum_field_alignment);
|
|
|
530 rli->record_align = MAX (rli->record_align, tmp);
|
|
|
531 }
|
|
|
532 #endif
|
|
|
533
|
|
|
534 rli->offset = size_zero_node;
|
|
|
535 rli->bitpos = bitsize_zero_node;
|
|
|
536 rli->prev_field = 0;
|
|
|
537 rli->pending_statics = 0;
|
|
|
538 rli->packed_maybe_necessary = 0;
|
|
|
539 rli->remaining_in_alignment = 0;
|
|
|
540
|
|
|
541 return rli;
|
|
|
542 }
|
|
|
543
|
|
|
544 /* These four routines perform computations that convert between
|
|
|
545 the offset/bitpos forms and byte and bit offsets. */
|
|
|
546
|
|
|
547 tree
|
|
|
548 bit_from_pos (tree offset, tree bitpos)
|
|
|
549 {
|
|
|
550 return size_binop (PLUS_EXPR, bitpos,
|
|
|
551 size_binop (MULT_EXPR,
|
|
|
552 fold_convert (bitsizetype, offset),
|
|
|
553 bitsize_unit_node));
|
|
|
554 }
|
|
|
555
|
|
|
556 tree
|
|
|
557 byte_from_pos (tree offset, tree bitpos)
|
|
|
558 {
|
|
|
559 return size_binop (PLUS_EXPR, offset,
|
|
|
560 fold_convert (sizetype,
|
|
|
561 size_binop (TRUNC_DIV_EXPR, bitpos,
|
|
|
562 bitsize_unit_node)));
|
|
|
563 }
|
|
|
564
|
|
|
565 void
|
|
|
566 pos_from_bit (tree *poffset, tree *pbitpos, unsigned int off_align,
|
|
|
567 tree pos)
|
|
|
568 {
|
|
|
569 *poffset = size_binop (MULT_EXPR,
|
|
|
570 fold_convert (sizetype,
|
|
|
571 size_binop (FLOOR_DIV_EXPR, pos,
|
|
|
572 bitsize_int (off_align))),
|
|
|
573 size_int (off_align / BITS_PER_UNIT));
|
|
|
574 *pbitpos = size_binop (FLOOR_MOD_EXPR, pos, bitsize_int (off_align));
|
|
|
575 }
|
|
|
576
|
|
|
577 /* Given a pointer to bit and byte offsets and an offset alignment,
|
|
|
578 normalize the offsets so they are within the alignment. */
|
|
|
579
|
|
|
580 void
|
|
|
581 normalize_offset (tree *poffset, tree *pbitpos, unsigned int off_align)
|
|
|
582 {
|
|
|
583 /* If the bit position is now larger than it should be, adjust it
|
|
|
584 downwards. */
|
|
|
585 if (compare_tree_int (*pbitpos, off_align) >= 0)
|
|
|
586 {
|
|
|
587 tree extra_aligns = size_binop (FLOOR_DIV_EXPR, *pbitpos,
|
|
|
588 bitsize_int (off_align));
|
|
|
589
|
|
|
590 *poffset
|
|
|
591 = size_binop (PLUS_EXPR, *poffset,
|
|
|
592 size_binop (MULT_EXPR,
|
|
|
593 fold_convert (sizetype, extra_aligns),
|
|
|
594 size_int (off_align / BITS_PER_UNIT)));
|
|
|
595
|
|
|
596 *pbitpos
|
|
|
597 = size_binop (FLOOR_MOD_EXPR, *pbitpos, bitsize_int (off_align));
|
|
|
598 }
|
|
|
599 }
|
|
|
600
|
|
|
601 /* Print debugging information about the information in RLI. */
|
|
|
602
|
|
|
603 void
|
|
|
604 debug_rli (record_layout_info rli)
|
|
|
605 {
|
|
|
606 print_node_brief (stderr, "type", rli->t, 0);
|
|
|
607 print_node_brief (stderr, "\noffset", rli->offset, 0);
|
|
|
608 print_node_brief (stderr, " bitpos", rli->bitpos, 0);
|
|
|
609
|
|
|
610 fprintf (stderr, "\naligns: rec = %u, unpack = %u, off = %u\n",
|
|
|
611 rli->record_align, rli->unpacked_align,
|
|
|
612 rli->offset_align);
|
|
|
613
|
|
|
614 /* The ms_struct code is the only that uses this. */
|
|
|
615 if (targetm.ms_bitfield_layout_p (rli->t))
|
|
|
616 fprintf (stderr, "remaining in alignment = %u\n", rli->remaining_in_alignment);
|
|
|
617
|
|
|
618 if (rli->packed_maybe_necessary)
|
|
|
619 fprintf (stderr, "packed may be necessary\n");
|
|
|
620
|
|
|
621 if (rli->pending_statics)
|
|
|
622 {
|
|
|
623 fprintf (stderr, "pending statics:\n");
|
|
|
624 debug_tree (rli->pending_statics);
|
|
|
625 }
|
|
|
626 }
|
|
|
627
|
|
|
628 /* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and
|
|
|
629 BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */
|
|
|
630
|
|
|
631 void
|
|
|
632 normalize_rli (record_layout_info rli)
|
|
|
633 {
|
|
|
634 normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align);
|
|
|
635 }
|
|
|
636
|
|
|
637 /* Returns the size in bytes allocated so far. */
|
|
|
638
|
|
|
639 tree
|
|
|
640 rli_size_unit_so_far (record_layout_info rli)
|
|
|
641 {
|
|
|
642 return byte_from_pos (rli->offset, rli->bitpos);
|
|
|
643 }
|
|
|
644
|
|
|
645 /* Returns the size in bits allocated so far. */
|
|
|
646
|
|
|
647 tree
|
|
|
648 rli_size_so_far (record_layout_info rli)
|
|
|
649 {
|
|
|
650 return bit_from_pos (rli->offset, rli->bitpos);
|
|
|
651 }
|
|
|
652
|
|
|
653 /* FIELD is about to be added to RLI->T. The alignment (in bits) of
|
|
|
654 the next available location within the record is given by KNOWN_ALIGN.
|
|
|
655 Update the variable alignment fields in RLI, and return the alignment
|
|
|
656 to give the FIELD. */
|
|
|
657
|
|
|
658 unsigned int
|
|
|
659 update_alignment_for_field (record_layout_info rli, tree field,
|
|
|
660 unsigned int known_align)
|
|
|
661 {
|
|
|
662 /* The alignment required for FIELD. */
|
|
|
663 unsigned int desired_align;
|
|
|
664 /* The type of this field. */
|
|
|
665 tree type = TREE_TYPE (field);
|
|
|
666 /* True if the field was explicitly aligned by the user. */
|
|
|
667 bool user_align;
|
|
|
668 bool is_bitfield;
|
|
|
669
|
|
|
670 /* Do not attempt to align an ERROR_MARK node */
|
|
|
671 if (TREE_CODE (type) == ERROR_MARK)
|
|
|
672 return 0;
|
|
|
673
|
|
|
674 /* Lay out the field so we know what alignment it needs. */
|
|
|
675 layout_decl (field, known_align);
|
|
|
676 desired_align = DECL_ALIGN (field);
|
|
|
677 user_align = DECL_USER_ALIGN (field);
|
|
|
678
|
|
|
679 is_bitfield = (type != error_mark_node
|
|
|
680 && DECL_BIT_FIELD_TYPE (field)
|
|
|
681 && ! integer_zerop (TYPE_SIZE (type)));
|
|
|
682
|
|
|
683 /* Record must have at least as much alignment as any field.
|
|
|
684 Otherwise, the alignment of the field within the record is
|
|
|
685 meaningless. */
|
|
|
686 if (targetm.ms_bitfield_layout_p (rli->t))
|
|
|
687 {
|
|
|
688 /* Here, the alignment of the underlying type of a bitfield can
|
|
|
689 affect the alignment of a record; even a zero-sized field
|
|
|
690 can do this. The alignment should be to the alignment of
|
|
|
691 the type, except that for zero-size bitfields this only
|
|
|
692 applies if there was an immediately prior, nonzero-size
|
|
|
693 bitfield. (That's the way it is, experimentally.) */
|
|
|
694 if ((!is_bitfield && !DECL_PACKED (field))
|
|
|
695 || (!integer_zerop (DECL_SIZE (field))
|
|
|
696 ? !DECL_PACKED (field)
|
|
|
697 : (rli->prev_field
|
|
|
698 && DECL_BIT_FIELD_TYPE (rli->prev_field)
|
|
|
699 && ! integer_zerop (DECL_SIZE (rli->prev_field)))))
|
|
|
700 {
|
|
|
701 unsigned int type_align = TYPE_ALIGN (type);
|
|
|
702 type_align = MAX (type_align, desired_align);
|
|
|
703 if (maximum_field_alignment != 0)
|
|
|
704 type_align = MIN (type_align, maximum_field_alignment);
|
|
|
705 rli->record_align = MAX (rli->record_align, type_align);
|
|
|
706 rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
|
|
|
707 }
|
|
|
708 }
|
|
|
709 #ifdef PCC_BITFIELD_TYPE_MATTERS
|
|
|
710 else if (is_bitfield && PCC_BITFIELD_TYPE_MATTERS)
|
|
|
711 {
|
|
|
712 /* Named bit-fields cause the entire structure to have the
|
|
|
713 alignment implied by their type. Some targets also apply the same
|
|
|
714 rules to unnamed bitfields. */
|
|
|
715 if (DECL_NAME (field) != 0
|
|
|
716 || targetm.align_anon_bitfield ())
|
|
|
717 {
|
|
|
718 unsigned int type_align = TYPE_ALIGN (type);
|
|
|
719
|
|
|
720 #ifdef ADJUST_FIELD_ALIGN
|
|
|
721 if (! TYPE_USER_ALIGN (type))
|
|
|
722 type_align = ADJUST_FIELD_ALIGN (field, type_align);
|
|
|
723 #endif
|
|
|
724
|
|
|
725 /* Targets might chose to handle unnamed and hence possibly
|
|
|
726 zero-width bitfield. Those are not influenced by #pragmas
|
|
|
727 or packed attributes. */
|
|
|
728 if (integer_zerop (DECL_SIZE (field)))
|
|
|
729 {
|
|
|
730 if (initial_max_fld_align)
|
|
|
731 type_align = MIN (type_align,
|
|
|
732 initial_max_fld_align * BITS_PER_UNIT);
|
|
|
733 }
|
|
|
734 else if (maximum_field_alignment != 0)
|
|
|
735 type_align = MIN (type_align, maximum_field_alignment);
|
|
|
736 else if (DECL_PACKED (field))
|
|
|
737 type_align = MIN (type_align, BITS_PER_UNIT);
|
|
|
738
|
|
|
739 /* The alignment of the record is increased to the maximum
|
|
|
740 of the current alignment, the alignment indicated on the
|
|
|
741 field (i.e., the alignment specified by an __aligned__
|
|
|
742 attribute), and the alignment indicated by the type of
|
|
|
743 the field. */
|
|
|
744 rli->record_align = MAX (rli->record_align, desired_align);
|
|
|
745 rli->record_align = MAX (rli->record_align, type_align);
|
|
|
746
|
|
|
747 if (warn_packed)
|
|
|
748 rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
|
|
|
749 user_align |= TYPE_USER_ALIGN (type);
|
|
|
750 }
|
|
|
751 }
|
|
|
752 #endif
|
|
|
753 else
|
|
|
754 {
|
|
|
755 rli->record_align = MAX (rli->record_align, desired_align);
|
|
|
756 rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
|
|
|
757 }
|
|
|
758
|
|
|
759 TYPE_USER_ALIGN (rli->t) |= user_align;
|
|
|
760
|
|
|
761 return desired_align;
|
|
|
762 }
|
|
|
763
|
|
|
764 /* Called from place_field to handle unions. */
|
|
|
765
|
|
|
766 static void
|
|
|
767 place_union_field (record_layout_info rli, tree field)
|
|
|
768 {
|
|
|
769 update_alignment_for_field (rli, field, /*known_align=*/0);
|
|
|
770
|
|
|
771 DECL_FIELD_OFFSET (field) = size_zero_node;
|
|
|
772 DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node;
|
|
|
773 SET_DECL_OFFSET_ALIGN (field, BIGGEST_ALIGNMENT);
|
|
|
774
|
|
|
775 /* If this is an ERROR_MARK return *after* having set the
|
|
|
776 field at the start of the union. This helps when parsing
|
|
|
777 invalid fields. */
|
|
|
778 if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK)
|
|
|
779 return;
|
|
|
780
|
|
|
781 /* We assume the union's size will be a multiple of a byte so we don't
|
|
|
782 bother with BITPOS. */
|
|
|
783 if (TREE_CODE (rli->t) == UNION_TYPE)
|
|
|
784 rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field));
|
|
|
785 else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE)
|
|
|
786 rli->offset = fold_build3 (COND_EXPR, sizetype,
|
|
|
787 DECL_QUALIFIER (field),
|
|
|
788 DECL_SIZE_UNIT (field), rli->offset);
|
|
|
789 }
|
|
|
790
|
|
|
791 #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED)
|
|
|
792 /* A bitfield of SIZE with a required access alignment of ALIGN is allocated
|
|
|
793 at BYTE_OFFSET / BIT_OFFSET. Return nonzero if the field would span more
|
|
|
794 units of alignment than the underlying TYPE. */
|
|
|
795 static int
|
|
|
796 excess_unit_span (HOST_WIDE_INT byte_offset, HOST_WIDE_INT bit_offset,
|
|
|
797 HOST_WIDE_INT size, HOST_WIDE_INT align, tree type)
|
|
|
798 {
|
|
|
799 /* Note that the calculation of OFFSET might overflow; we calculate it so
|
|
|
800 that we still get the right result as long as ALIGN is a power of two. */
|
|
|
801 unsigned HOST_WIDE_INT offset = byte_offset * BITS_PER_UNIT + bit_offset;
|
|
|
802
|
|
|
803 offset = offset % align;
|
|
|
804 return ((offset + size + align - 1) / align
|
|
|
805 > ((unsigned HOST_WIDE_INT) tree_low_cst (TYPE_SIZE (type), 1)
|
|
|
806 / align));
|
|
|
807 }
|
|
|
808 #endif
|
|
|
809
|
|
|
810 /* RLI contains information about the layout of a RECORD_TYPE. FIELD
|
|
|
811 is a FIELD_DECL to be added after those fields already present in
|
|
|
812 T. (FIELD is not actually added to the TYPE_FIELDS list here;
|
|
|
813 callers that desire that behavior must manually perform that step.) */
|
|
|
814
|
|
|
815 void
|
|
|
816 place_field (record_layout_info rli, tree field)
|
|
|
817 {
|
|
|
818 /* The alignment required for FIELD. */
|
|
|
819 unsigned int desired_align;
|
|
|
820 /* The alignment FIELD would have if we just dropped it into the
|
|
|
821 record as it presently stands. */
|
|
|
822 unsigned int known_align;
|
|
|
823 unsigned int actual_align;
|
|
|
824 /* The type of this field. */
|
|
|
825 tree type = TREE_TYPE (field);
|
|
|
826
|
|
|
827 gcc_assert (TREE_CODE (field) != ERROR_MARK);
|
|
|
828
|
|
|
829 /* If FIELD is static, then treat it like a separate variable, not
|
|
|
830 really like a structure field. If it is a FUNCTION_DECL, it's a
|
|
|
831 method. In both cases, all we do is lay out the decl, and we do
|
|
|
832 it *after* the record is laid out. */
|
|
|
833 if (TREE_CODE (field) == VAR_DECL)
|
|
|
834 {
|
|
|
835 rli->pending_statics = tree_cons (NULL_TREE, field,
|
|
|
836 rli->pending_statics);
|
|
|
837 return;
|
|
|
838 }
|
|
|
839
|
|
|
840 /* Enumerators and enum types which are local to this class need not
|
|
|
841 be laid out. Likewise for initialized constant fields. */
|
|
|
842 else if (TREE_CODE (field) != FIELD_DECL)
|
|
|
843 return;
|
|
|
844
|
|
|
845 /* Unions are laid out very differently than records, so split
|
|
|
846 that code off to another function. */
|
|
|
847 else if (TREE_CODE (rli->t) != RECORD_TYPE)
|
|
|
848 {
|
|
|
849 place_union_field (rli, field);
|
|
|
850 return;
|
|
|
851 }
|
|
|
852
|
|
|
853 else if (TREE_CODE (type) == ERROR_MARK)
|
|
|
854 {
|
|
|
855 /* Place this field at the current allocation position, so we
|
|
|
856 maintain monotonicity. */
|
|
|
857 DECL_FIELD_OFFSET (field) = rli->offset;
|
|
|
858 DECL_FIELD_BIT_OFFSET (field) = rli->bitpos;
|
|
|
859 SET_DECL_OFFSET_ALIGN (field, rli->offset_align);
|
|
|
860 return;
|
|
|
861 }
|
|
|
862
|
|
|
863 /* Work out the known alignment so far. Note that A & (-A) is the
|
|
|
864 value of the least-significant bit in A that is one. */
|
|
|
865 if (! integer_zerop (rli->bitpos))
|
|
|
866 known_align = (tree_low_cst (rli->bitpos, 1)
|
|
|
867 & - tree_low_cst (rli->bitpos, 1));
|
|
|
868 else if (integer_zerop (rli->offset))
|
|
|
869 known_align = 0;
|
|
|
870 else if (host_integerp (rli->offset, 1))
|
|
|
871 known_align = (BITS_PER_UNIT
|
|
|
872 * (tree_low_cst (rli->offset, 1)
|
|
|
873 & - tree_low_cst (rli->offset, 1)));
|
|
|
874 else
|
|
|
875 known_align = rli->offset_align;
|
|
|
876
|
|
|
877 desired_align = update_alignment_for_field (rli, field, known_align);
|
|
|
878 if (known_align == 0)
|
|
|
879 known_align = MAX (BIGGEST_ALIGNMENT, rli->record_align);
|
|
|
880
|
|
|
881 if (warn_packed && DECL_PACKED (field))
|
|
|
882 {
|
|
|
883 if (known_align >= TYPE_ALIGN (type))
|
|
|
884 {
|
|
|
885 if (TYPE_ALIGN (type) > desired_align)
|
|
|
886 {
|
|
|
887 if (STRICT_ALIGNMENT)
|
|
|
888 warning (OPT_Wattributes, "packed attribute causes "
|
|
|
889 "inefficient alignment for %q+D", field);
|
|
|
890 else
|
|
|
891 warning (OPT_Wattributes, "packed attribute is "
|
|
|
892 "unnecessary for %q+D", field);
|
|
|
893 }
|
|
|
894 }
|
|
|
895 else
|
|
|
896 rli->packed_maybe_necessary = 1;
|
|
|
897 }
|
|
|
898
|
|
|
899 /* Does this field automatically have alignment it needs by virtue
|
|
|
900 of the fields that precede it and the record's own alignment?
|
|
|
901 We already align ms_struct fields, so don't re-align them. */
|
|
|
902 if (known_align < desired_align
|
|
|
903 && !targetm.ms_bitfield_layout_p (rli->t))
|
|
|
904 {
|
|
|
905 /* No, we need to skip space before this field.
|
|
|
906 Bump the cumulative size to multiple of field alignment. */
|
|
|
907
|
|
|
908 warning (OPT_Wpadded, "padding struct to align %q+D", field);
|
|
|
909
|
|
|
910 /* If the alignment is still within offset_align, just align
|
|
|
911 the bit position. */
|
|
|
912 if (desired_align < rli->offset_align)
|
|
|
913 rli->bitpos = round_up (rli->bitpos, desired_align);
|
|
|
914 else
|
|
|
915 {
|
|
|
916 /* First adjust OFFSET by the partial bits, then align. */
|
|
|
917 rli->offset
|
|
|
918 = size_binop (PLUS_EXPR, rli->offset,
|
|
|
919 fold_convert (sizetype,
|
|
|
920 size_binop (CEIL_DIV_EXPR, rli->bitpos,
|
|
|
921 bitsize_unit_node)));
|
|
|
922 rli->bitpos = bitsize_zero_node;
|
|
|
923
|
|
|
924 rli->offset = round_up (rli->offset, desired_align / BITS_PER_UNIT);
|
|
|
925 }
|
|
|
926
|
|
|
927 if (! TREE_CONSTANT (rli->offset))
|
|
|
928 rli->offset_align = desired_align;
|
|
|
929
|
|
|
930 }
|
|
|
931
|
|
|
932 /* Handle compatibility with PCC. Note that if the record has any
|
|
|
933 variable-sized fields, we need not worry about compatibility. */
|
|
|
934 #ifdef PCC_BITFIELD_TYPE_MATTERS
|
|
|
935 if (PCC_BITFIELD_TYPE_MATTERS
|
|
|
936 && ! targetm.ms_bitfield_layout_p (rli->t)
|
|
|
937 && TREE_CODE (field) == FIELD_DECL
|
|
|
938 && type != error_mark_node
|
|
|
939 && DECL_BIT_FIELD (field)
|
|
|
940 && (! DECL_PACKED (field)
|
|
|
941 /* Enter for these packed fields only to issue a warning. */
|
|
|
942 || TYPE_ALIGN (type) <= BITS_PER_UNIT)
|
|
|
943 && maximum_field_alignment == 0
|
|
|
944 && ! integer_zerop (DECL_SIZE (field))
|
|
|
945 && host_integerp (DECL_SIZE (field), 1)
|
|
|
946 && host_integerp (rli->offset, 1)
|
|
|
947 && host_integerp (TYPE_SIZE (type), 1))
|
|
|
948 {
|
|
|
949 unsigned int type_align = TYPE_ALIGN (type);
|
|
|
950 tree dsize = DECL_SIZE (field);
|
|
|
951 HOST_WIDE_INT field_size = tree_low_cst (dsize, 1);
|
|
|
952 HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0);
|
|
|
953 HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0);
|
|
|
954
|
|
|
955 #ifdef ADJUST_FIELD_ALIGN
|
|
|
956 if (! TYPE_USER_ALIGN (type))
|
|
|
957 type_align = ADJUST_FIELD_ALIGN (field, type_align);
|
|
|
958 #endif
|
|
|
959
|
|
|
960 /* A bit field may not span more units of alignment of its type
|
|
|
961 than its type itself. Advance to next boundary if necessary. */
|
|
|
962 if (excess_unit_span (offset, bit_offset, field_size, type_align, type))
|
|
|
963 {
|
|
|
964 if (DECL_PACKED (field))
|
|
|
965 {
|
|
|
966 if (warn_packed_bitfield_compat == 1)
|
|
|
967 inform
|
|
|
968 (input_location,
|
|
|
969 "Offset of packed bit-field %qD has changed in GCC 4.4",
|
|
|
970 field);
|
|
|
971 }
|
|
|
972 else
|
|
|
973 rli->bitpos = round_up (rli->bitpos, type_align);
|
|
|
974 }
|
|
|
975
|
|
|
976 if (! DECL_PACKED (field))
|
|
|
977 TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type);
|
|
|
978 }
|
|
|
979 #endif
|
|
|
980
|
|
|
981 #ifdef BITFIELD_NBYTES_LIMITED
|
|
|
982 if (BITFIELD_NBYTES_LIMITED
|
|
|
983 && ! targetm.ms_bitfield_layout_p (rli->t)
|
|
|
984 && TREE_CODE (field) == FIELD_DECL
|
|
|
985 && type != error_mark_node
|
|
|
986 && DECL_BIT_FIELD_TYPE (field)
|
|
|
987 && ! DECL_PACKED (field)
|
|
|
988 && ! integer_zerop (DECL_SIZE (field))
|
|
|
989 && host_integerp (DECL_SIZE (field), 1)
|
|
|
990 && host_integerp (rli->offset, 1)
|
|
|
991 && host_integerp (TYPE_SIZE (type), 1))
|
|
|
992 {
|
|
|
993 unsigned int type_align = TYPE_ALIGN (type);
|
|
|
994 tree dsize = DECL_SIZE (field);
|
|
|
995 HOST_WIDE_INT field_size = tree_low_cst (dsize, 1);
|
|
|
996 HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0);
|
|
|
997 HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0);
|
|
|
998
|
|
|
999 #ifdef ADJUST_FIELD_ALIGN
|
|
|
1000 if (! TYPE_USER_ALIGN (type))
|
|
|
1001 type_align = ADJUST_FIELD_ALIGN (field, type_align);
|
|
|
1002 #endif
|
|
|
1003
|
|
|
1004 if (maximum_field_alignment != 0)
|
|
|
1005 type_align = MIN (type_align, maximum_field_alignment);
|
|
|
1006 /* ??? This test is opposite the test in the containing if
|
|
|
1007 statement, so this code is unreachable currently. */
|
|
|
1008 else if (DECL_PACKED (field))
|
|
|
1009 type_align = MIN (type_align, BITS_PER_UNIT);
|
|
|
1010
|
|
|
1011 /* A bit field may not span the unit of alignment of its type.
|
|
|
1012 Advance to next boundary if necessary. */
|
|
|
1013 if (excess_unit_span (offset, bit_offset, field_size, type_align, type))
|
|
|
1014 rli->bitpos = round_up (rli->bitpos, type_align);
|
|
|
1015
|
|
|
1016 TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type);
|
|
|
1017 }
|
|
|
1018 #endif
|
|
|
1019
|
|
|
1020 /* See the docs for TARGET_MS_BITFIELD_LAYOUT_P for details.
|
|
|
1021 A subtlety:
|
|
|
1022 When a bit field is inserted into a packed record, the whole
|
|
|
1023 size of the underlying type is used by one or more same-size
|
|
|
1024 adjacent bitfields. (That is, if its long:3, 32 bits is
|
|
|
1025 used in the record, and any additional adjacent long bitfields are
|
|
|
1026 packed into the same chunk of 32 bits. However, if the size
|
|
|
1027 changes, a new field of that size is allocated.) In an unpacked
|
|
|
1028 record, this is the same as using alignment, but not equivalent
|
|
|
1029 when packing.
|
|
|
1030
|
|
|
1031 Note: for compatibility, we use the type size, not the type alignment
|
|
|
1032 to determine alignment, since that matches the documentation */
|
|
|
1033
|
|
|
1034 if (targetm.ms_bitfield_layout_p (rli->t))
|
|
|
1035 {
|
|
|
1036 tree prev_saved = rli->prev_field;
|
|
|
1037 tree prev_type = prev_saved ? DECL_BIT_FIELD_TYPE (prev_saved) : NULL;
|
|
|
1038
|
|
|
1039 /* This is a bitfield if it exists. */
|
|
|
1040 if (rli->prev_field)
|
|
|
1041 {
|
|
|
1042 /* If both are bitfields, nonzero, and the same size, this is
|
|
|
1043 the middle of a run. Zero declared size fields are special
|
|
|
1044 and handled as "end of run". (Note: it's nonzero declared
|
|
|
1045 size, but equal type sizes!) (Since we know that both
|
|
|
1046 the current and previous fields are bitfields by the
|
|
|
1047 time we check it, DECL_SIZE must be present for both.) */
|
|
|
1048 if (DECL_BIT_FIELD_TYPE (field)
|
|
|
1049 && !integer_zerop (DECL_SIZE (field))
|
|
|
1050 && !integer_zerop (DECL_SIZE (rli->prev_field))
|
|
|
1051 && host_integerp (DECL_SIZE (rli->prev_field), 0)
|
|
|
1052 && host_integerp (TYPE_SIZE (type), 0)
|
|
|
1053 && simple_cst_equal (TYPE_SIZE (type), TYPE_SIZE (prev_type)))
|
|
|
1054 {
|
|
|
1055 /* We're in the middle of a run of equal type size fields; make
|
|
|
1056 sure we realign if we run out of bits. (Not decl size,
|
|
|
1057 type size!) */
|
|
|
1058 HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 1);
|
|
|
1059
|
|
|
1060 if (rli->remaining_in_alignment < bitsize)
|
|
|
1061 {
|
|
|
1062 HOST_WIDE_INT typesize = tree_low_cst (TYPE_SIZE (type), 1);
|
|
|
1063
|
|
|
1064 /* out of bits; bump up to next 'word'. */
|
|
|
1065 rli->bitpos
|
|
|
1066 = size_binop (PLUS_EXPR, rli->bitpos,
|
|
|
1067 bitsize_int (rli->remaining_in_alignment));
|
|
|
1068 rli->prev_field = field;
|
|
|
1069 if (typesize < bitsize)
|
|
|
1070 rli->remaining_in_alignment = 0;
|
|
|
1071 else
|
|
|
1072 rli->remaining_in_alignment = typesize - bitsize;
|
|
|
1073 }
|
|
|
1074 else
|
|
|
1075 rli->remaining_in_alignment -= bitsize;
|
|
|
1076 }
|
|
|
1077 else
|
|
|
1078 {
|
|
|
1079 /* End of a run: if leaving a run of bitfields of the same type
|
|
|
1080 size, we have to "use up" the rest of the bits of the type
|
|
|
1081 size.
|
|
|
1082
|
|
|
1083 Compute the new position as the sum of the size for the prior
|
|
|
1084 type and where we first started working on that type.
|
|
|
1085 Note: since the beginning of the field was aligned then
|
|
|
1086 of course the end will be too. No round needed. */
|
|
|
1087
|
|
|
1088 if (!integer_zerop (DECL_SIZE (rli->prev_field)))
|
|
|
1089 {
|
|
|
1090 rli->bitpos
|
|
|
1091 = size_binop (PLUS_EXPR, rli->bitpos,
|
|
|
1092 bitsize_int (rli->remaining_in_alignment));
|
|
|
1093 }
|
|
|
1094 else
|
|
|
1095 /* We "use up" size zero fields; the code below should behave
|
|
|
1096 as if the prior field was not a bitfield. */
|
|
|
1097 prev_saved = NULL;
|
|
|
1098
|
|
|
1099 /* Cause a new bitfield to be captured, either this time (if
|
|
|
1100 currently a bitfield) or next time we see one. */
|
|
|
1101 if (!DECL_BIT_FIELD_TYPE(field)
|
|
|
1102 || integer_zerop (DECL_SIZE (field)))
|
|
|
1103 rli->prev_field = NULL;
|
|
|
1104 }
|
|
|
1105
|
|
|
1106 normalize_rli (rli);
|
|
|
1107 }
|
|
|
1108
|
|
|
1109 /* If we're starting a new run of same size type bitfields
|
|
|
1110 (or a run of non-bitfields), set up the "first of the run"
|
|
|
1111 fields.
|
|
|
1112
|
|
|
1113 That is, if the current field is not a bitfield, or if there
|
|
|
1114 was a prior bitfield the type sizes differ, or if there wasn't
|
|
|
1115 a prior bitfield the size of the current field is nonzero.
|
|
|
1116
|
|
|
1117 Note: we must be sure to test ONLY the type size if there was
|
|
|
1118 a prior bitfield and ONLY for the current field being zero if
|
|
|
1119 there wasn't. */
|
|
|
1120
|
|
|
1121 if (!DECL_BIT_FIELD_TYPE (field)
|
|
|
1122 || (prev_saved != NULL
|
|
|
1123 ? !simple_cst_equal (TYPE_SIZE (type), TYPE_SIZE (prev_type))
|
|
|
1124 : !integer_zerop (DECL_SIZE (field)) ))
|
|
|
1125 {
|
|
|
1126 /* Never smaller than a byte for compatibility. */
|
|
|
1127 unsigned int type_align = BITS_PER_UNIT;
|
|
|
1128
|
|
|
1129 /* (When not a bitfield), we could be seeing a flex array (with
|
|
|
1130 no DECL_SIZE). Since we won't be using remaining_in_alignment
|
|
|
1131 until we see a bitfield (and come by here again) we just skip
|
|
|
1132 calculating it. */
|
|
|
1133 if (DECL_SIZE (field) != NULL
|
|
|
1134 && host_integerp (TYPE_SIZE (TREE_TYPE (field)), 0)
|
|
|
1135 && host_integerp (DECL_SIZE (field), 0))
|
|
|
1136 {
|
|
|
1137 HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 1);
|
|
|
1138 HOST_WIDE_INT typesize
|
|
|
1139 = tree_low_cst (TYPE_SIZE (TREE_TYPE (field)), 1);
|
|
|
1140
|
|
|
1141 if (typesize < bitsize)
|
|
|
1142 rli->remaining_in_alignment = 0;
|
|
|
1143 else
|
|
|
1144 rli->remaining_in_alignment = typesize - bitsize;
|
|
|
1145 }
|
|
|
1146
|
|
|
1147 /* Now align (conventionally) for the new type. */
|
|
|
1148 type_align = TYPE_ALIGN (TREE_TYPE (field));
|
|
|
1149
|
|
|
1150 if (maximum_field_alignment != 0)
|
|
|
1151 type_align = MIN (type_align, maximum_field_alignment);
|
|
|
1152
|
|
|
1153 rli->bitpos = round_up (rli->bitpos, type_align);
|
|
|
1154
|
|
|
1155 /* If we really aligned, don't allow subsequent bitfields
|
|
|
1156 to undo that. */
|
|
|
1157 rli->prev_field = NULL;
|
|
|
1158 }
|
|
|
1159 }
|
|
|
1160
|
|
|
1161 /* Offset so far becomes the position of this field after normalizing. */
|
|
|
1162 normalize_rli (rli);
|
|
|
1163 DECL_FIELD_OFFSET (field) = rli->offset;
|
|
|
1164 DECL_FIELD_BIT_OFFSET (field) = rli->bitpos;
|
|
|
1165 SET_DECL_OFFSET_ALIGN (field, rli->offset_align);
|
|
|
1166
|
|
|
1167 /* If this field ended up more aligned than we thought it would be (we
|
|
|
1168 approximate this by seeing if its position changed), lay out the field
|
|
|
1169 again; perhaps we can use an integral mode for it now. */
|
|
|
1170 if (! integer_zerop (DECL_FIELD_BIT_OFFSET (field)))
|
|
|
1171 actual_align = (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)
|
|
|
1172 & - tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1));
|
|
|
1173 else if (integer_zerop (DECL_FIELD_OFFSET (field)))
|
|
|
1174 actual_align = MAX (BIGGEST_ALIGNMENT, rli->record_align);
|
|
|
1175 else if (host_integerp (DECL_FIELD_OFFSET (field), 1))
|
|
|
1176 actual_align = (BITS_PER_UNIT
|
|
|
1177 * (tree_low_cst (DECL_FIELD_OFFSET (field), 1)
|
|
|
1178 & - tree_low_cst (DECL_FIELD_OFFSET (field), 1)));
|
|
|
1179 else
|
|
|
1180 actual_align = DECL_OFFSET_ALIGN (field);
|
|
|
1181 /* ACTUAL_ALIGN is still the actual alignment *within the record* .
|
|
|
1182 store / extract bit field operations will check the alignment of the
|
|
|
1183 record against the mode of bit fields. */
|
|
|
1184
|
|
|
1185 if (known_align != actual_align)
|
|
|
1186 layout_decl (field, actual_align);
|
|
|
1187
|
|
|
1188 if (rli->prev_field == NULL && DECL_BIT_FIELD_TYPE (field))
|
|
|
1189 rli->prev_field = field;
|
|
|
1190
|
|
|
1191 /* Now add size of this field to the size of the record. If the size is
|
|
|
1192 not constant, treat the field as being a multiple of bytes and just
|
|
|
1193 adjust the offset, resetting the bit position. Otherwise, apportion the
|
|
|
1194 size amongst the bit position and offset. First handle the case of an
|
|
|
1195 unspecified size, which can happen when we have an invalid nested struct
|
|
|
1196 definition, such as struct j { struct j { int i; } }. The error message
|
|
|
1197 is printed in finish_struct. */
|
|
|
1198 if (DECL_SIZE (field) == 0)
|
|
|
1199 /* Do nothing. */;
|
|
|
1200 else if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST
|
|
|
1201 || TREE_OVERFLOW (DECL_SIZE (field)))
|
|
|
1202 {
|
|
|
1203 rli->offset
|
|
|
1204 = size_binop (PLUS_EXPR, rli->offset,
|
|
|
1205 fold_convert (sizetype,
|
|
|
1206 size_binop (CEIL_DIV_EXPR, rli->bitpos,
|
|
|
1207 bitsize_unit_node)));
|
|
|
1208 rli->offset
|
|
|
1209 = size_binop (PLUS_EXPR, rli->offset, DECL_SIZE_UNIT (field));
|
|
|
1210 rli->bitpos = bitsize_zero_node;
|
|
|
1211 rli->offset_align = MIN (rli->offset_align, desired_align);
|
|
|
1212 }
|
|
|
1213 else if (targetm.ms_bitfield_layout_p (rli->t))
|
|
|
1214 {
|
|
|
1215 rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field));
|
|
|
1216
|
|
|
1217 /* If we ended a bitfield before the full length of the type then
|
|
|
1218 pad the struct out to the full length of the last type. */
|
|
|
1219 if ((TREE_CHAIN (field) == NULL
|
|
|
1220 || TREE_CODE (TREE_CHAIN (field)) != FIELD_DECL)
|
|
|
1221 && DECL_BIT_FIELD_TYPE (field)
|
|
|
1222 && !integer_zerop (DECL_SIZE (field)))
|
|
|
1223 rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos,
|
|
|
1224 bitsize_int (rli->remaining_in_alignment));
|
|
|
1225
|
|
|
1226 normalize_rli (rli);
|
|
|
1227 }
|
|
|
1228 else
|
|
|
1229 {
|
|
|
1230 rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field));
|
|
|
1231 normalize_rli (rli);
|
|
|
1232 }
|
|
|
1233 }
|
|
|
1234
|
|
|
1235 /* Assuming that all the fields have been laid out, this function uses
|
|
|
1236 RLI to compute the final TYPE_SIZE, TYPE_ALIGN, etc. for the type
|
|
|
1237 indicated by RLI. */
|
|
|
1238
|
|
|
1239 static void
|
|
|
1240 finalize_record_size (record_layout_info rli)
|
|
|
1241 {
|
|
|
1242 tree unpadded_size, unpadded_size_unit;
|
|
|
1243
|
|
|
1244 /* Now we want just byte and bit offsets, so set the offset alignment
|
|
|
1245 to be a byte and then normalize. */
|
|
|
1246 rli->offset_align = BITS_PER_UNIT;
|
|
|
1247 normalize_rli (rli);
|
|
|
1248
|
|
|
1249 /* Determine the desired alignment. */
|
|
|
1250 #ifdef ROUND_TYPE_ALIGN
|
|
|
1251 TYPE_ALIGN (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t),
|
|
|
1252 rli->record_align);
|
|
|
1253 #else
|
|
|
1254 TYPE_ALIGN (rli->t) = MAX (TYPE_ALIGN (rli->t), rli->record_align);
|
|
|
1255 #endif
|
|
|
1256
|
|
|
1257 /* Compute the size so far. Be sure to allow for extra bits in the
|
|
|
1258 size in bytes. We have guaranteed above that it will be no more
|
|
|
1259 than a single byte. */
|
|
|
1260 unpadded_size = rli_size_so_far (rli);
|
|
|
1261 unpadded_size_unit = rli_size_unit_so_far (rli);
|
|
|
1262 if (! integer_zerop (rli->bitpos))
|
|
|
1263 unpadded_size_unit
|
|
|
1264 = size_binop (PLUS_EXPR, unpadded_size_unit, size_one_node);
|
|
|
1265
|
|
|
1266 /* Round the size up to be a multiple of the required alignment. */
|
|
|
1267 TYPE_SIZE (rli->t) = round_up (unpadded_size, TYPE_ALIGN (rli->t));
|
|
|
1268 TYPE_SIZE_UNIT (rli->t)
|
|
|
1269 = round_up (unpadded_size_unit, TYPE_ALIGN_UNIT (rli->t));
|
|
|
1270
|
|
|
1271 if (TREE_CONSTANT (unpadded_size)
|
|
|
1272 && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0)
|
|
|
1273 warning (OPT_Wpadded, "padding struct size to alignment boundary");
|
|
|
1274
|
|
|
1275 if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE
|
|
|
1276 && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary
|
|
|
1277 && TREE_CONSTANT (unpadded_size))
|
|
|
1278 {
|
|
|
1279 tree unpacked_size;
|
|
|
1280
|
|
|
1281 #ifdef ROUND_TYPE_ALIGN
|
|
|
1282 rli->unpacked_align
|
|
|
1283 = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align);
|
|
|
1284 #else
|
|
|
1285 rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align);
|
|
|
1286 #endif
|
|
|
1287
|
|
|
1288 unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align);
|
|
|
1289 if (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t)))
|
|
|
1290 {
|
|
|
1291 TYPE_PACKED (rli->t) = 0;
|
|
|
1292
|
|
|
1293 if (TYPE_NAME (rli->t))
|
|
|
1294 {
|
|
|
1295 const char *name;
|
|
|
1296
|
|
|
1297 if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE)
|
|
|
1298 name = IDENTIFIER_POINTER (TYPE_NAME (rli->t));
|
|
|
1299 else
|
|
|
1300 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t)));
|
|
|
1301
|
|
|
1302 if (STRICT_ALIGNMENT)
|
|
|
1303 warning (OPT_Wpacked, "packed attribute causes inefficient "
|
|
|
1304 "alignment for %qs", name);
|
|
|
1305 else
|
|
|
1306 warning (OPT_Wpacked,
|
|
|
1307 "packed attribute is unnecessary for %qs", name);
|
|
|
1308 }
|
|
|
1309 else
|
|
|
1310 {
|
|
|
1311 if (STRICT_ALIGNMENT)
|
|
|
1312 warning (OPT_Wpacked,
|
|
|
1313 "packed attribute causes inefficient alignment");
|
|
|
1314 else
|
|
|
1315 warning (OPT_Wpacked, "packed attribute is unnecessary");
|
|
|
1316 }
|
|
|
1317 }
|
|
|
1318 }
|
|
|
1319 }
|
|
|
1320
|
|
|
1321 /* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */
|
|
|
1322
|
|
|
1323 void
|
|
|
1324 compute_record_mode (tree type)
|
|
|
1325 {
|
|
|
1326 tree field;
|
|
|
1327 enum machine_mode mode = VOIDmode;
|
|
|
1328
|
|
|
1329 /* Most RECORD_TYPEs have BLKmode, so we start off assuming that.
|
|
|
1330 However, if possible, we use a mode that fits in a register
|
|
|
1331 instead, in order to allow for better optimization down the
|
|
|
1332 line. */
|
|
|
1333 SET_TYPE_MODE (type, BLKmode);
|
|
|
1334
|
|
|
1335 if (! host_integerp (TYPE_SIZE (type), 1))
|
|
|
1336 return;
|
|
|
1337
|
|
|
1338 /* A record which has any BLKmode members must itself be
|
|
|
1339 BLKmode; it can't go in a register. Unless the member is
|
|
|
1340 BLKmode only because it isn't aligned. */
|
|
|
1341 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
|
|
|
1342 {
|
|
|
1343 if (TREE_CODE (field) != FIELD_DECL)
|
|
|
1344 continue;
|
|
|
1345
|
|
|
1346 if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK
|
|
|
1347 || (TYPE_MODE (TREE_TYPE (field)) == BLKmode
|
|
|
1348 && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field))
|
|
|
1349 && !(TYPE_SIZE (TREE_TYPE (field)) != 0
|
|
|
1350 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))))
|
|
|
1351 || ! host_integerp (bit_position (field), 1)
|
|
|
1352 || DECL_SIZE (field) == 0
|
|
|
1353 || ! host_integerp (DECL_SIZE (field), 1))
|
|
|
1354 return;
|
|
|
1355
|
|
|
1356 /* If this field is the whole struct, remember its mode so
|
|
|
1357 that, say, we can put a double in a class into a DF
|
|
|
1358 register instead of forcing it to live in the stack. */
|
|
|
1359 if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field)))
|
|
|
1360 mode = DECL_MODE (field);
|
|
|
1361
|
|
|
1362 #ifdef MEMBER_TYPE_FORCES_BLK
|
|
|
1363 /* With some targets, eg. c4x, it is sub-optimal
|
|
|
1364 to access an aligned BLKmode structure as a scalar. */
|
|
|
1365
|
|
|
1366 if (MEMBER_TYPE_FORCES_BLK (field, mode))
|
|
|
1367 return;
|
|
|
1368 #endif /* MEMBER_TYPE_FORCES_BLK */
|
|
|
1369 }
|
|
|
1370
|
|
|
1371 /* If we only have one real field; use its mode if that mode's size
|
|
|
1372 matches the type's size. This only applies to RECORD_TYPE. This
|
|
|
1373 does not apply to unions. */
|
|
|
1374 if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode
|
|
|
1375 && host_integerp (TYPE_SIZE (type), 1)
|
|
|
1376 && GET_MODE_BITSIZE (mode) == TREE_INT_CST_LOW (TYPE_SIZE (type)))
|
|
|
1377 SET_TYPE_MODE (type, mode);
|
|
|
1378 else
|
|
|
1379 SET_TYPE_MODE (type, mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1));
|
|
|
1380
|
|
|
1381 /* If structure's known alignment is less than what the scalar
|
|
|
1382 mode would need, and it matters, then stick with BLKmode. */
|
|
|
1383 if (TYPE_MODE (type) != BLKmode
|
|
|
1384 && STRICT_ALIGNMENT
|
|
|
1385 && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT
|
|
|
1386 || TYPE_ALIGN (type) >= GET_MODE_ALIGNMENT (TYPE_MODE (type))))
|
|
|
1387 {
|
|
|
1388 /* If this is the only reason this type is BLKmode, then
|
|
|
1389 don't force containing types to be BLKmode. */
|
|
|
1390 TYPE_NO_FORCE_BLK (type) = 1;
|
|
|
1391 SET_TYPE_MODE (type, BLKmode);
|
|
|
1392 }
|
|
|
1393 }
|
|
|
1394
|
|
|
1395 /* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid
|
|
|
1396 out. */
|
|
|
1397
|
|
|
1398 static void
|
|
|
1399 finalize_type_size (tree type)
|
|
|
1400 {
|
|
|
1401 /* Normally, use the alignment corresponding to the mode chosen.
|
|
|
1402 However, where strict alignment is not required, avoid
|
|
|
1403 over-aligning structures, since most compilers do not do this
|
|
|
1404 alignment. */
|
|
|
1405
|
|
|
1406 if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode
|
|
|
1407 && (STRICT_ALIGNMENT
|
|
|
1408 || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE
|
|
|
1409 && TREE_CODE (type) != QUAL_UNION_TYPE
|
|
|
1410 && TREE_CODE (type) != ARRAY_TYPE)))
|
|
|
1411 {
|
|
|
1412 unsigned mode_align = GET_MODE_ALIGNMENT (TYPE_MODE (type));
|
|
|
1413
|
|
|
1414 /* Don't override a larger alignment requirement coming from a user
|
|
|
1415 alignment of one of the fields. */
|
|
|
1416 if (mode_align >= TYPE_ALIGN (type))
|
|
|
1417 {
|
|
|
1418 TYPE_ALIGN (type) = mode_align;
|
|
|
1419 TYPE_USER_ALIGN (type) = 0;
|
|
|
1420 }
|
|
|
1421 }
|
|
|
1422
|
|
|
1423 /* Do machine-dependent extra alignment. */
|
|
|
1424 #ifdef ROUND_TYPE_ALIGN
|
|
|
1425 TYPE_ALIGN (type)
|
|
|
1426 = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT);
|
|
|
1427 #endif
|
|
|
1428
|
|
|
1429 /* If we failed to find a simple way to calculate the unit size
|
|
|
1430 of the type, find it by division. */
|
|
|
1431 if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0)
|
|
|
1432 /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the
|
|
|
1433 result will fit in sizetype. We will get more efficient code using
|
|
|
1434 sizetype, so we force a conversion. */
|
|
|
1435 TYPE_SIZE_UNIT (type)
|
|
|
1436 = fold_convert (sizetype,
|
|
|
1437 size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type),
|
|
|
1438 bitsize_unit_node));
|
|
|
1439
|
|
|
1440 if (TYPE_SIZE (type) != 0)
|
|
|
1441 {
|
|
|
1442 TYPE_SIZE (type) = round_up (TYPE_SIZE (type), TYPE_ALIGN (type));
|
|
|
1443 TYPE_SIZE_UNIT (type) = round_up (TYPE_SIZE_UNIT (type),
|
|
|
1444 TYPE_ALIGN_UNIT (type));
|
|
|
1445 }
|
|
|
1446
|
|
|
1447 /* Evaluate nonconstant sizes only once, either now or as soon as safe. */
|
|
|
1448 if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
|
|
|
1449 TYPE_SIZE (type) = variable_size (TYPE_SIZE (type));
|
|
|
1450 if (TYPE_SIZE_UNIT (type) != 0
|
|
|
1451 && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
|
|
|
1452 TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type));
|
|
|
1453
|
|
|
1454 /* Also layout any other variants of the type. */
|
|
|
1455 if (TYPE_NEXT_VARIANT (type)
|
|
|
1456 || type != TYPE_MAIN_VARIANT (type))
|
|
|
1457 {
|
|
|
1458 tree variant;
|
|
|
1459 /* Record layout info of this variant. */
|
|
|
1460 tree size = TYPE_SIZE (type);
|
|
|
1461 tree size_unit = TYPE_SIZE_UNIT (type);
|
|
|
1462 unsigned int align = TYPE_ALIGN (type);
|
|
|
1463 unsigned int user_align = TYPE_USER_ALIGN (type);
|
|
|
1464 enum machine_mode mode = TYPE_MODE (type);
|
|
|
1465
|
|
|
1466 /* Copy it into all variants. */
|
|
|
1467 for (variant = TYPE_MAIN_VARIANT (type);
|
|
|
1468 variant != 0;
|
|
|
1469 variant = TYPE_NEXT_VARIANT (variant))
|
|
|
1470 {
|
|
|
1471 TYPE_SIZE (variant) = size;
|
|
|
1472 TYPE_SIZE_UNIT (variant) = size_unit;
|
|
|
1473 TYPE_ALIGN (variant) = align;
|
|
|
1474 TYPE_USER_ALIGN (variant) = user_align;
|
|
|
1475 SET_TYPE_MODE (variant, mode);
|
|
|
1476 }
|
|
|
1477 }
|
|
|
1478 }
|
|
|
1479
|
|
|
1480 /* Do all of the work required to layout the type indicated by RLI,
|
|
|
1481 once the fields have been laid out. This function will call `free'
|
|
|
1482 for RLI, unless FREE_P is false. Passing a value other than false
|
|
|
1483 for FREE_P is bad practice; this option only exists to support the
|
|
|
1484 G++ 3.2 ABI. */
|
|
|
1485
|
|
|
1486 void
|
|
|
1487 finish_record_layout (record_layout_info rli, int free_p)
|
|
|
1488 {
|
|
|
1489 tree variant;
|
|
|
1490
|
|
|
1491 /* Compute the final size. */
|
|
|
1492 finalize_record_size (rli);
|
|
|
1493
|
|
|
1494 /* Compute the TYPE_MODE for the record. */
|
|
|
1495 compute_record_mode (rli->t);
|
|
|
1496
|
|
|
1497 /* Perform any last tweaks to the TYPE_SIZE, etc. */
|
|
|
1498 finalize_type_size (rli->t);
|
|
|
1499
|
|
|
1500 /* Propagate TYPE_PACKED to variants. With C++ templates,
|
|
|
1501 handle_packed_attribute is too early to do this. */
|
|
|
1502 for (variant = TYPE_NEXT_VARIANT (rli->t); variant;
|
|
|
1503 variant = TYPE_NEXT_VARIANT (variant))
|
|
|
1504 TYPE_PACKED (variant) = TYPE_PACKED (rli->t);
|
|
|
1505
|
|
|
1506 /* Lay out any static members. This is done now because their type
|
|
|
1507 may use the record's type. */
|
|
|
1508 while (rli->pending_statics)
|
|
|
1509 {
|
|
|
1510 layout_decl (TREE_VALUE (rli->pending_statics), 0);
|
|
|
1511 rli->pending_statics = TREE_CHAIN (rli->pending_statics);
|
|
|
1512 }
|
|
|
1513
|
|
|
1514 /* Clean up. */
|
|
|
1515 if (free_p)
|
|
|
1516 free (rli);
|
|
|
1517 }
|
|
|
1518
|
|
|
1519
|
|
|
1520 /* Finish processing a builtin RECORD_TYPE type TYPE. It's name is
|
|
|
1521 NAME, its fields are chained in reverse on FIELDS.
|
|
|
1522
|
|
|
1523 If ALIGN_TYPE is non-null, it is given the same alignment as
|
|
|
1524 ALIGN_TYPE. */
|
|
|
1525
|
|
|
1526 void
|
|
|
1527 finish_builtin_struct (tree type, const char *name, tree fields,
|
|
|
1528 tree align_type)
|
|
|
1529 {
|
|
|
1530 tree tail, next;
|
|
|
1531
|
|
|
1532 for (tail = NULL_TREE; fields; tail = fields, fields = next)
|
|
|
1533 {
|
|
|
1534 DECL_FIELD_CONTEXT (fields) = type;
|
|
|
1535 next = TREE_CHAIN (fields);
|
|
|
1536 TREE_CHAIN (fields) = tail;
|
|
|
1537 }
|
|
|
1538 TYPE_FIELDS (type) = tail;
|
|
|
1539
|
|
|
1540 if (align_type)
|
|
|
1541 {
|
|
|
1542 TYPE_ALIGN (type) = TYPE_ALIGN (align_type);
|
|
|
1543 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (align_type);
|
|
|
1544 }
|
|
|
1545
|
|
|
1546 layout_type (type);
|
|
|
1547 #if 0 /* not yet, should get fixed properly later */
|
|
|
1548 TYPE_NAME (type) = make_type_decl (get_identifier (name), type);
|
|
|
1549 #else
|
|
|
1550 TYPE_NAME (type) = build_decl (TYPE_DECL, get_identifier (name), type);
|
|
|
1551 #endif
|
|
|
1552 TYPE_STUB_DECL (type) = TYPE_NAME (type);
|
|
|
1553 layout_decl (TYPE_NAME (type), 0);
|
|
|
1554 }
|
|
|
1555
|
|
|
1556 /* Calculate the mode, size, and alignment for TYPE.
|
|
|
1557 For an array type, calculate the element separation as well.
|
|
|
1558 Record TYPE on the chain of permanent or temporary types
|
|
|
1559 so that dbxout will find out about it.
|
|
|
1560
|
|
|
1561 TYPE_SIZE of a type is nonzero if the type has been laid out already.
|
|
|
1562 layout_type does nothing on such a type.
|
|
|
1563
|
|
|
1564 If the type is incomplete, its TYPE_SIZE remains zero. */
|
|
|
1565
|
|
|
1566 void
|
|
|
1567 layout_type (tree type)
|
|
|
1568 {
|
|
|
1569 gcc_assert (type);
|
|
|
1570
|
|
|
1571 if (type == error_mark_node)
|
|
|
1572 return;
|
|
|
1573
|
|
|
1574 /* Do nothing if type has been laid out before. */
|
|
|
1575 if (TYPE_SIZE (type))
|
|
|
1576 return;
|
|
|
1577
|
|
|
1578 switch (TREE_CODE (type))
|
|
|
1579 {
|
|
|
1580 case LANG_TYPE:
|
|
|
1581 /* This kind of type is the responsibility
|
|
|
1582 of the language-specific code. */
|
|
|
1583 gcc_unreachable ();
|
|
|
1584
|
|
|
1585 case BOOLEAN_TYPE: /* Used for Java, Pascal, and Chill. */
|
|
|
1586 if (TYPE_PRECISION (type) == 0)
|
|
|
1587 TYPE_PRECISION (type) = 1; /* default to one byte/boolean. */
|
|
|
1588
|
|
|
1589 /* ... fall through ... */
|
|
|
1590
|
|
|
1591 case INTEGER_TYPE:
|
|
|
1592 case ENUMERAL_TYPE:
|
|
|
1593 if (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
|
|
|
1594 && tree_int_cst_sgn (TYPE_MIN_VALUE (type)) >= 0)
|
|
|
1595 TYPE_UNSIGNED (type) = 1;
|
|
|
1596
|
|
|
1597 SET_TYPE_MODE (type,
|
|
|
1598 smallest_mode_for_size (TYPE_PRECISION (type), MODE_INT));
|
|
|
1599 TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
|
|
|
1600 TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
|
|
|
1601 break;
|
|
|
1602
|
|
|
1603 case REAL_TYPE:
|
|
|
1604 SET_TYPE_MODE (type,
|
|
|
1605 mode_for_size (TYPE_PRECISION (type), MODE_FLOAT, 0));
|
|
|
1606 TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
|
|
|
1607 TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
|
|
|
1608 break;
|
|
|
1609
|
|
|
1610 case FIXED_POINT_TYPE:
|
|
|
1611 /* TYPE_MODE (type) has been set already. */
|
|
|
1612 TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
|
|
|
1613 TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
|
|
|
1614 break;
|
|
|
1615
|
|
|
1616 case COMPLEX_TYPE:
|
|
|
1617 TYPE_UNSIGNED (type) = TYPE_UNSIGNED (TREE_TYPE (type));
|
|
|
1618 SET_TYPE_MODE (type,
|
|
|
1619 mode_for_size (2 * TYPE_PRECISION (TREE_TYPE (type)),
|
|
|
1620 (TREE_CODE (TREE_TYPE (type)) == REAL_TYPE
|
|
|
1621 ? MODE_COMPLEX_FLOAT : MODE_COMPLEX_INT),
|
|
|
1622 0));
|
|
|
1623 TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
|
|
|
1624 TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
|
|
|
1625 break;
|
|
|
1626
|
|
|
1627 case VECTOR_TYPE:
|
|
|
1628 {
|
|
|
1629 int nunits = TYPE_VECTOR_SUBPARTS (type);
|
|
|
1630 tree innertype = TREE_TYPE (type);
|
|
|
1631
|
|
|
1632 gcc_assert (!(nunits & (nunits - 1)));
|
|
|
1633
|
|
|
1634 /* Find an appropriate mode for the vector type. */
|
|
|
1635 if (TYPE_MODE (type) == VOIDmode)
|
|
|
1636 {
|
|
|
1637 enum machine_mode innermode = TYPE_MODE (innertype);
|
|
|
1638 enum machine_mode mode;
|
|
|
1639
|
|
|
1640 /* First, look for a supported vector type. */
|
|
|
1641 if (SCALAR_FLOAT_MODE_P (innermode))
|
|
|
1642 mode = MIN_MODE_VECTOR_FLOAT;
|
|
|
1643 else if (SCALAR_FRACT_MODE_P (innermode))
|
|
|
1644 mode = MIN_MODE_VECTOR_FRACT;
|
|
|
1645 else if (SCALAR_UFRACT_MODE_P (innermode))
|
|
|
1646 mode = MIN_MODE_VECTOR_UFRACT;
|
|
|
1647 else if (SCALAR_ACCUM_MODE_P (innermode))
|
|
|
1648 mode = MIN_MODE_VECTOR_ACCUM;
|
|
|
1649 else if (SCALAR_UACCUM_MODE_P (innermode))
|
|
|
1650 mode = MIN_MODE_VECTOR_UACCUM;
|
|
|
1651 else
|
|
|
1652 mode = MIN_MODE_VECTOR_INT;
|
|
|
1653
|
|
|
1654 /* Do not check vector_mode_supported_p here. We'll do that
|
|
|
1655 later in vector_type_mode. */
|
|
|
1656 for (; mode != VOIDmode ; mode = GET_MODE_WIDER_MODE (mode))
|
|
|
1657 if (GET_MODE_NUNITS (mode) == nunits
|
|
|
1658 && GET_MODE_INNER (mode) == innermode)
|
|
|
1659 break;
|
|
|
1660
|
|
|
1661 /* For integers, try mapping it to a same-sized scalar mode. */
|
|
|
1662 if (mode == VOIDmode
|
|
|
1663 && GET_MODE_CLASS (innermode) == MODE_INT)
|
|
|
1664 mode = mode_for_size (nunits * GET_MODE_BITSIZE (innermode),
|
|
|
1665 MODE_INT, 0);
|
|
|
1666
|
|
|
1667 if (mode == VOIDmode ||
|
|
|
1668 (GET_MODE_CLASS (mode) == MODE_INT
|
|
|
1669 && !have_regs_of_mode[mode]))
|
|
|
1670 SET_TYPE_MODE (type, BLKmode);
|
|
|
1671 else
|
|
|
1672 SET_TYPE_MODE (type, mode);
|
|
|
1673 }
|
|
|
1674
|
|
|
1675 TYPE_SATURATING (type) = TYPE_SATURATING (TREE_TYPE (type));
|
|
|
1676 TYPE_UNSIGNED (type) = TYPE_UNSIGNED (TREE_TYPE (type));
|
|
|
1677 TYPE_SIZE_UNIT (type) = int_const_binop (MULT_EXPR,
|
|
|
1678 TYPE_SIZE_UNIT (innertype),
|
|
|
1679 size_int (nunits), 0);
|
|
|
1680 TYPE_SIZE (type) = int_const_binop (MULT_EXPR, TYPE_SIZE (innertype),
|
|
|
1681 bitsize_int (nunits), 0);
|
|
|
1682
|
|
|
1683 /* Always naturally align vectors. This prevents ABI changes
|
|
|
1684 depending on whether or not native vector modes are supported. */
|
|
|
1685 TYPE_ALIGN (type) = tree_low_cst (TYPE_SIZE (type), 0);
|
|
|
1686 break;
|
|
|
1687 }
|
|
|
1688
|
|
|
1689 case VOID_TYPE:
|
|
|
1690 /* This is an incomplete type and so doesn't have a size. */
|
|
|
1691 TYPE_ALIGN (type) = 1;
|
|
|
1692 TYPE_USER_ALIGN (type) = 0;
|
|
|
1693 SET_TYPE_MODE (type, VOIDmode);
|
|
|
1694 break;
|
|
|
1695
|
|
|
1696 case OFFSET_TYPE:
|
|
|
1697 TYPE_SIZE (type) = bitsize_int (POINTER_SIZE);
|
|
|
1698 TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT);
|
|
|
1699 /* A pointer might be MODE_PARTIAL_INT,
|
|
|
1700 but ptrdiff_t must be integral. */
|
|
|
1701 SET_TYPE_MODE (type, mode_for_size (POINTER_SIZE, MODE_INT, 0));
|
|
|
1702 break;
|
|
|
1703
|
|
|
1704 case FUNCTION_TYPE:
|
|
|
1705 case METHOD_TYPE:
|
|
|
1706 /* It's hard to see what the mode and size of a function ought to
|
|
|
1707 be, but we do know the alignment is FUNCTION_BOUNDARY, so
|
|
|
1708 make it consistent with that. */
|
|
|
1709 SET_TYPE_MODE (type, mode_for_size (FUNCTION_BOUNDARY, MODE_INT, 0));
|
|
|
1710 TYPE_SIZE (type) = bitsize_int (FUNCTION_BOUNDARY);
|
|
|
1711 TYPE_SIZE_UNIT (type) = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
|
|
|
1712 break;
|
|
|
1713
|
|
|
1714 case POINTER_TYPE:
|
|
|
1715 case REFERENCE_TYPE:
|
|
|
1716 {
|
|
|
1717 enum machine_mode mode = ((TREE_CODE (type) == REFERENCE_TYPE
|
|
|
1718 && reference_types_internal)
|
|
|
1719 ? Pmode : TYPE_MODE (type));
|
|
|
1720
|
|
|
1721 int nbits = GET_MODE_BITSIZE (mode);
|
|
|
1722
|
|
|
1723 TYPE_SIZE (type) = bitsize_int (nbits);
|
|
|
1724 TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (mode));
|
|
|
1725 TYPE_UNSIGNED (type) = 1;
|
|
|
1726 TYPE_PRECISION (type) = nbits;
|
|
|
1727 }
|
|
|
1728 break;
|
|
|
1729
|
|
|
1730 case ARRAY_TYPE:
|
|
|
1731 {
|
|
|
1732 tree index = TYPE_DOMAIN (type);
|
|
|
1733 tree element = TREE_TYPE (type);
|
|
|
1734
|
|
|
1735 build_pointer_type (element);
|
|
|
1736
|
|
|
1737 /* We need to know both bounds in order to compute the size. */
|
|
|
1738 if (index && TYPE_MAX_VALUE (index) && TYPE_MIN_VALUE (index)
|
|
|
1739 && TYPE_SIZE (element))
|
|
|
1740 {
|
|
|
1741 tree ub = TYPE_MAX_VALUE (index);
|
|
|
1742 tree lb = TYPE_MIN_VALUE (index);
|
|
|
1743 tree length;
|
|
|
1744 tree element_size;
|
|
|
1745
|
|
|
1746 /* The initial subtraction should happen in the original type so
|
|
|
1747 that (possible) negative values are handled appropriately. */
|
|
|
1748 length = size_binop (PLUS_EXPR, size_one_node,
|
|
|
1749 fold_convert (sizetype,
|
|
|
1750 fold_build2 (MINUS_EXPR,
|
|
|
1751 TREE_TYPE (lb),
|
|
|
1752 ub, lb)));
|
|
|
1753
|
|
|
1754 /* Special handling for arrays of bits (for Chill). */
|
|
|
1755 element_size = TYPE_SIZE (element);
|
|
|
1756 if (TYPE_PACKED (type) && INTEGRAL_TYPE_P (element)
|
|
|
1757 && (integer_zerop (TYPE_MAX_VALUE (element))
|
|
|
1758 || integer_onep (TYPE_MAX_VALUE (element)))
|
|
|
1759 && host_integerp (TYPE_MIN_VALUE (element), 1))
|
|
|
1760 {
|
|
|
1761 HOST_WIDE_INT maxvalue
|
|
|
1762 = tree_low_cst (TYPE_MAX_VALUE (element), 1);
|
|
|
1763 HOST_WIDE_INT minvalue
|
|
|
1764 = tree_low_cst (TYPE_MIN_VALUE (element), 1);
|
|
|
1765
|
|
|
1766 if (maxvalue - minvalue == 1
|
|
|
1767 && (maxvalue == 1 || maxvalue == 0))
|
|
|
1768 element_size = integer_one_node;
|
|
|
1769 }
|
|
|
1770
|
|
|
1771 /* If neither bound is a constant and sizetype is signed, make
|
|
|
1772 sure the size is never negative. We should really do this
|
|
|
1773 if *either* bound is non-constant, but this is the best
|
|
|
1774 compromise between C and Ada. */
|
|
|
1775 if (!TYPE_UNSIGNED (sizetype)
|
|
|
1776 && TREE_CODE (TYPE_MIN_VALUE (index)) != INTEGER_CST
|
|
|
1777 && TREE_CODE (TYPE_MAX_VALUE (index)) != INTEGER_CST)
|
|
|
1778 length = size_binop (MAX_EXPR, length, size_zero_node);
|
|
|
1779
|
|
|
1780 TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size,
|
|
|
1781 fold_convert (bitsizetype,
|
|
|
1782 length));
|
|
|
1783
|
|
|
1784 /* If we know the size of the element, calculate the total
|
|
|
1785 size directly, rather than do some division thing below.
|
|
|
1786 This optimization helps Fortran assumed-size arrays
|
|
|
1787 (where the size of the array is determined at runtime)
|
|
|
1788 substantially.
|
|
|
1789 Note that we can't do this in the case where the size of
|
|
|
1790 the elements is one bit since TYPE_SIZE_UNIT cannot be
|
|
|
1791 set correctly in that case. */
|
|
|
1792 if (TYPE_SIZE_UNIT (element) != 0 && ! integer_onep (element_size))
|
|
|
1793 TYPE_SIZE_UNIT (type)
|
|
|
1794 = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length);
|
|
|
1795 }
|
|
|
1796
|
|
|
1797 /* Now round the alignment and size,
|
|
|
1798 using machine-dependent criteria if any. */
|
|
|
1799
|
|
|
1800 #ifdef ROUND_TYPE_ALIGN
|
|
|
1801 TYPE_ALIGN (type)
|
|
|
1802 = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (element), BITS_PER_UNIT);
|
|
|
1803 #else
|
|
|
1804 TYPE_ALIGN (type) = MAX (TYPE_ALIGN (element), BITS_PER_UNIT);
|
|
|
1805 #endif
|
|
|
1806 if (!TYPE_SIZE (element))
|
|
|
1807 /* We don't know the size of the underlying element type, so
|
|
|
1808 our alignment calculations will be wrong, forcing us to
|
|
|
1809 fall back on structural equality. */
|
|
|
1810 SET_TYPE_STRUCTURAL_EQUALITY (type);
|
|
|
1811 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (element);
|
|
|
1812 SET_TYPE_MODE (type, BLKmode);
|
|
|
1813 if (TYPE_SIZE (type) != 0
|
|
|
1814 #ifdef MEMBER_TYPE_FORCES_BLK
|
|
|
1815 && ! MEMBER_TYPE_FORCES_BLK (type, VOIDmode)
|
|
|
1816 #endif
|
|
|
1817 /* BLKmode elements force BLKmode aggregate;
|
|
|
1818 else extract/store fields may lose. */
|
|
|
1819 && (TYPE_MODE (TREE_TYPE (type)) != BLKmode
|
|
|
1820 || TYPE_NO_FORCE_BLK (TREE_TYPE (type))))
|
|
|
1821 {
|
|
|
1822 /* One-element arrays get the component type's mode. */
|
|
|
1823 if (simple_cst_equal (TYPE_SIZE (type),
|
|
|
1824 TYPE_SIZE (TREE_TYPE (type))))
|
|
|
1825 SET_TYPE_MODE (type, TYPE_MODE (TREE_TYPE (type)));
|
|
|
1826 else
|
|
|
1827 SET_TYPE_MODE (type, mode_for_size_tree (TYPE_SIZE (type),
|
|
|
1828 MODE_INT, 1));
|
|
|
1829
|
|
|
1830 if (TYPE_MODE (type) != BLKmode
|
|
|
1831 && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT
|
|
|
1832 && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type)))
|
|
|
1833 {
|
|
|
1834 TYPE_NO_FORCE_BLK (type) = 1;
|
|
|
1835 SET_TYPE_MODE (type, BLKmode);
|
|
|
1836 }
|
|
|
1837 }
|
|
|
1838 /* When the element size is constant, check that it is at least as
|
|
|
1839 large as the element alignment. */
|
|
|
1840 if (TYPE_SIZE_UNIT (element)
|
|
|
1841 && TREE_CODE (TYPE_SIZE_UNIT (element)) == INTEGER_CST
|
|
|
1842 /* If TYPE_SIZE_UNIT overflowed, then it is certainly larger than
|
|
|
1843 TYPE_ALIGN_UNIT. */
|
|
|
1844 && !TREE_OVERFLOW (TYPE_SIZE_UNIT (element))
|
|
|
1845 && !integer_zerop (TYPE_SIZE_UNIT (element))
|
|
|
1846 && compare_tree_int (TYPE_SIZE_UNIT (element),
|
|
|
1847 TYPE_ALIGN_UNIT (element)) < 0)
|
|
|
1848 error ("alignment of array elements is greater than element size");
|
|
|
1849 break;
|
|
|
1850 }
|
|
|
1851
|
|
|
1852 case RECORD_TYPE:
|
|
|
1853 case UNION_TYPE:
|
|
|
1854 case QUAL_UNION_TYPE:
|
|
|
1855 {
|
|
|
1856 tree field;
|
|
|
1857 record_layout_info rli;
|
|
|
1858
|
|
|
1859 /* Initialize the layout information. */
|
|
|
1860 rli = start_record_layout (type);
|
|
|
1861
|
|
|
1862 /* If this is a QUAL_UNION_TYPE, we want to process the fields
|
|
|
1863 in the reverse order in building the COND_EXPR that denotes
|
|
|
1864 its size. We reverse them again later. */
|
|
|
1865 if (TREE_CODE (type) == QUAL_UNION_TYPE)
|
|
|
1866 TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type));
|
|
|
1867
|
|
|
1868 /* Place all the fields. */
|
|
|
1869 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
|
|
|
1870 place_field (rli, field);
|
|
|
1871
|
|
|
1872 if (TREE_CODE (type) == QUAL_UNION_TYPE)
|
|
|
1873 TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type));
|
|
|
1874
|
|
|
1875 /* Finish laying out the record. */
|
|
|
1876 finish_record_layout (rli, /*free_p=*/true);
|
|
|
1877 }
|
|
|
1878 break;
|
|
|
1879
|
|
|
1880 default:
|
|
|
1881 gcc_unreachable ();
|
|
|
1882 }
|
|
|
1883
|
|
|
1884 /* Compute the final TYPE_SIZE, TYPE_ALIGN, etc. for TYPE. For
|
|
|
1885 records and unions, finish_record_layout already called this
|
|
|
1886 function. */
|
|
|
1887 if (TREE_CODE (type) != RECORD_TYPE
|
|
|
1888 && TREE_CODE (type) != UNION_TYPE
|
|
|
1889 && TREE_CODE (type) != QUAL_UNION_TYPE)
|
|
|
1890 finalize_type_size (type);
|
|
|
1891
|
|
|
1892 /* We should never see alias sets on incomplete aggregates. And we
|
|
|
1893 should not call layout_type on not incomplete aggregates. */
|
|
|
1894 if (AGGREGATE_TYPE_P (type))
|
|
|
1895 gcc_assert (!TYPE_ALIAS_SET_KNOWN_P (type));
|
|
|
1896 }
|
|
|
1897
|
|
|
1898 /* Vector types need to re-check the target flags each time we report
|
|
|
1899 the machine mode. We need to do this because attribute target can
|
|
|
1900 change the result of vector_mode_supported_p and have_regs_of_mode
|
|
|
1901 on a per-function basis. Thus the TYPE_MODE of a VECTOR_TYPE can
|
|
|
1902 change on a per-function basis. */
|
|
|
1903 /* ??? Possibly a better solution is to run through all the types
|
|
|
1904 referenced by a function and re-compute the TYPE_MODE once, rather
|
|
|
1905 than make the TYPE_MODE macro call a function. */
|
|
|
1906
|
|
|
1907 enum machine_mode
|
|
|
1908 vector_type_mode (const_tree t)
|
|
|
1909 {
|
|
|
1910 enum machine_mode mode;
|
|
|
1911
|
|
|
1912 gcc_assert (TREE_CODE (t) == VECTOR_TYPE);
|
|
|
1913
|
|
|
1914 mode = t->type.mode;
|
|
|
1915 if (VECTOR_MODE_P (mode)
|
|
|
1916 && (!targetm.vector_mode_supported_p (mode)
|
|
|
1917 || !have_regs_of_mode[mode]))
|
|
|
1918 {
|
|
|
1919 enum machine_mode innermode = TREE_TYPE (t)->type.mode;
|
|
|
1920
|
|
|
1921 /* For integers, try mapping it to a same-sized scalar mode. */
|
|
|
1922 if (GET_MODE_CLASS (innermode) == MODE_INT)
|
|
|
1923 {
|
|
|
1924 mode = mode_for_size (TYPE_VECTOR_SUBPARTS (t)
|
|
|
1925 * GET_MODE_BITSIZE (innermode), MODE_INT, 0);
|
|
|
1926
|
|
|
1927 if (mode != VOIDmode && have_regs_of_mode[mode])
|
|
|
1928 return mode;
|
|
|
1929 }
|
|
|
1930
|
|
|
1931 return BLKmode;
|
|
|
1932 }
|
|
|
1933
|
|
|
1934 return mode;
|
|
|
1935 }
|
|
|
1936
|
|
|
1937 /* Create and return a type for signed integers of PRECISION bits. */
|
|
|
1938
|
|
|
1939 tree
|
|
|
1940 make_signed_type (int precision)
|
|
|
1941 {
|
|
|
1942 tree type = make_node (INTEGER_TYPE);
|
|
|
1943
|
|
|
1944 TYPE_PRECISION (type) = precision;
|
|
|
1945
|
|
|
1946 fixup_signed_type (type);
|
|
|
1947 return type;
|
|
|
1948 }
|
|
|
1949
|
|
|
1950 /* Create and return a type for unsigned integers of PRECISION bits. */
|
|
|
1951
|
|
|
1952 tree
|
|
|
1953 make_unsigned_type (int precision)
|
|
|
1954 {
|
|
|
1955 tree type = make_node (INTEGER_TYPE);
|
|
|
1956
|
|
|
1957 TYPE_PRECISION (type) = precision;
|
|
|
1958
|
|
|
1959 fixup_unsigned_type (type);
|
|
|
1960 return type;
|
|
|
1961 }
|
|
|
1962
|
|
|
1963 /* Create and return a type for fract of PRECISION bits, UNSIGNEDP,
|
|
|
1964 and SATP. */
|
|
|
1965
|
|
|
1966 tree
|
|
|
1967 make_fract_type (int precision, int unsignedp, int satp)
|
|
|
1968 {
|
|
|
1969 tree type = make_node (FIXED_POINT_TYPE);
|
|
|
1970
|
|
|
1971 TYPE_PRECISION (type) = precision;
|
|
|
1972
|
|
|
1973 if (satp)
|
|
|
1974 TYPE_SATURATING (type) = 1;
|
|
|
1975
|
|
|
1976 /* Lay out the type: set its alignment, size, etc. */
|
|
|
1977 if (unsignedp)
|
|
|
1978 {
|
|
|
1979 TYPE_UNSIGNED (type) = 1;
|
|
|
1980 SET_TYPE_MODE (type, mode_for_size (precision, MODE_UFRACT, 0));
|
|
|
1981 }
|
|
|
1982 else
|
|
|
1983 SET_TYPE_MODE (type, mode_for_size (precision, MODE_FRACT, 0));
|
|
|
1984 layout_type (type);
|
|
|
1985
|
|
|
1986 return type;
|
|
|
1987 }
|
|
|
1988
|
|
|
1989 /* Create and return a type for accum of PRECISION bits, UNSIGNEDP,
|
|
|
1990 and SATP. */
|
|
|
1991
|
|
|
1992 tree
|
|
|
1993 make_accum_type (int precision, int unsignedp, int satp)
|
|
|
1994 {
|
|
|
1995 tree type = make_node (FIXED_POINT_TYPE);
|
|
|
1996
|
|
|
1997 TYPE_PRECISION (type) = precision;
|
|
|
1998
|
|
|
1999 if (satp)
|
|
|
2000 TYPE_SATURATING (type) = 1;
|
|
|
2001
|
|
|
2002 /* Lay out the type: set its alignment, size, etc. */
|
|
|
2003 if (unsignedp)
|
|
|
2004 {
|
|
|
2005 TYPE_UNSIGNED (type) = 1;
|
|
|
2006 SET_TYPE_MODE (type, mode_for_size (precision, MODE_UACCUM, 0));
|
|
|
2007 }
|
|
|
2008 else
|
|
|
2009 SET_TYPE_MODE (type, mode_for_size (precision, MODE_ACCUM, 0));
|
|
|
2010 layout_type (type);
|
|
|
2011
|
|
|
2012 return type;
|
|
|
2013 }
|
|
|
2014
|
|
|
2015 /* Initialize sizetype and bitsizetype to a reasonable and temporary
|
|
|
2016 value to enable integer types to be created. */
|
|
|
2017
|
|
|
2018 void
|
|
|
2019 initialize_sizetypes (bool signed_p)
|
|
|
2020 {
|
|
|
2021 tree t = make_node (INTEGER_TYPE);
|
|
|
2022 int precision = GET_MODE_BITSIZE (SImode);
|
|
|
2023
|
|
|
2024 SET_TYPE_MODE (t, SImode);
|
|
|
2025 TYPE_ALIGN (t) = GET_MODE_ALIGNMENT (SImode);
|
|
|
2026 TYPE_USER_ALIGN (t) = 0;
|
|
|
2027 TYPE_IS_SIZETYPE (t) = 1;
|
|
|
2028 TYPE_UNSIGNED (t) = !signed_p;
|
|
|
2029 TYPE_SIZE (t) = build_int_cst (t, precision);
|
|
|
2030 TYPE_SIZE_UNIT (t) = build_int_cst (t, GET_MODE_SIZE (SImode));
|
|
|
2031 TYPE_PRECISION (t) = precision;
|
|
|
2032
|
|
|
2033 /* Set TYPE_MIN_VALUE and TYPE_MAX_VALUE. */
|
|
|
2034 set_min_and_max_values_for_integral_type (t, precision, !signed_p);
|
|
|
2035
|
|
|
2036 sizetype = t;
|
|
|
2037 bitsizetype = build_distinct_type_copy (t);
|
|
|
2038 }
|
|
|
2039
|
|
|
2040 /* Make sizetype a version of TYPE, and initialize *sizetype
|
|
|
2041 accordingly. We do this by overwriting the stub sizetype and
|
|
|
2042 bitsizetype nodes created by initialize_sizetypes. This makes sure
|
|
|
2043 that (a) anything stubby about them no longer exists, (b) any
|
|
|
2044 INTEGER_CSTs created with such a type, remain valid. */
|
|
|
2045
|
|
|
2046 void
|
|
|
2047 set_sizetype (tree type)
|
|
|
2048 {
|
|
|
2049 int oprecision = TYPE_PRECISION (type);
|
|
|
2050 /* The *bitsizetype types use a precision that avoids overflows when
|
|
|
2051 calculating signed sizes / offsets in bits. However, when
|
|
|
2052 cross-compiling from a 32 bit to a 64 bit host, we are limited to 64 bit
|
|
|
2053 precision. */
|
|
|
2054 int precision = MIN (MIN (oprecision + BITS_PER_UNIT_LOG + 1,
|
|
|
2055 MAX_FIXED_MODE_SIZE),
|
|
|
2056 2 * HOST_BITS_PER_WIDE_INT);
|
|
|
2057 tree t;
|
|
|
2058
|
|
|
2059 gcc_assert (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (sizetype));
|
|
|
2060
|
|
|
2061 t = build_distinct_type_copy (type);
|
|
|
2062 /* We do want to use sizetype's cache, as we will be replacing that
|
|
|
2063 type. */
|
|
|
2064 TYPE_CACHED_VALUES (t) = TYPE_CACHED_VALUES (sizetype);
|
|
|
2065 TYPE_CACHED_VALUES_P (t) = TYPE_CACHED_VALUES_P (sizetype);
|
|
|
2066 TREE_TYPE (TYPE_CACHED_VALUES (t)) = type;
|
|
|
2067 TYPE_UID (t) = TYPE_UID (sizetype);
|
|
|
2068 TYPE_IS_SIZETYPE (t) = 1;
|
|
|
2069
|
|
|
2070 /* Replace our original stub sizetype. */
|
|
|
2071 memcpy (sizetype, t, tree_size (sizetype));
|
|
|
2072 TYPE_MAIN_VARIANT (sizetype) = sizetype;
|
|
|
2073
|
|
|
2074 t = make_node (INTEGER_TYPE);
|
|
|
2075 TYPE_NAME (t) = get_identifier ("bit_size_type");
|
|
|
2076 /* We do want to use bitsizetype's cache, as we will be replacing that
|
|
|
2077 type. */
|
|
|
2078 TYPE_CACHED_VALUES (t) = TYPE_CACHED_VALUES (bitsizetype);
|
|
|
2079 TYPE_CACHED_VALUES_P (t) = TYPE_CACHED_VALUES_P (bitsizetype);
|
|
|
2080 TYPE_PRECISION (t) = precision;
|
|
|
2081 TYPE_UID (t) = TYPE_UID (bitsizetype);
|
|
|
2082 TYPE_IS_SIZETYPE (t) = 1;
|
|
|
2083
|
|
|
2084 /* Replace our original stub bitsizetype. */
|
|
|
2085 memcpy (bitsizetype, t, tree_size (bitsizetype));
|
|
|
2086 TYPE_MAIN_VARIANT (bitsizetype) = bitsizetype;
|
|
|
2087
|
|
|
2088 if (TYPE_UNSIGNED (type))
|
|
|
2089 {
|
|
|
2090 fixup_unsigned_type (bitsizetype);
|
|
|
2091 ssizetype = build_distinct_type_copy (make_signed_type (oprecision));
|
|
|
2092 TYPE_IS_SIZETYPE (ssizetype) = 1;
|
|
|
2093 sbitsizetype = build_distinct_type_copy (make_signed_type (precision));
|
|
|
2094 TYPE_IS_SIZETYPE (sbitsizetype) = 1;
|
|
|
2095 }
|
|
|
2096 else
|
|
|
2097 {
|
|
|
2098 fixup_signed_type (bitsizetype);
|
|
|
2099 ssizetype = sizetype;
|
|
|
2100 sbitsizetype = bitsizetype;
|
|
|
2101 }
|
|
|
2102
|
|
|
2103 /* If SIZETYPE is unsigned, we need to fix TYPE_MAX_VALUE so that
|
|
|
2104 it is sign extended in a way consistent with force_fit_type. */
|
|
|
2105 if (TYPE_UNSIGNED (type))
|
|
|
2106 {
|
|
|
2107 tree orig_max, new_max;
|
|
|
2108
|
|
|
2109 orig_max = TYPE_MAX_VALUE (sizetype);
|
|
|
2110
|
|
|
2111 /* Build a new node with the same values, but a different type.
|
|
|
2112 Sign extend it to ensure consistency. */
|
|
|
2113 new_max = build_int_cst_wide_type (sizetype,
|
|
|
2114 TREE_INT_CST_LOW (orig_max),
|
|
|
2115 TREE_INT_CST_HIGH (orig_max));
|
|
|
2116 TYPE_MAX_VALUE (sizetype) = new_max;
|
|
|
2117 }
|
|
|
2118 }
|
|
|
2119
|
|
|
2120 /* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE
|
|
|
2121 or BOOLEAN_TYPE. Set TYPE_MIN_VALUE and TYPE_MAX_VALUE
|
|
|
2122 for TYPE, based on the PRECISION and whether or not the TYPE
|
|
|
2123 IS_UNSIGNED. PRECISION need not correspond to a width supported
|
|
|
2124 natively by the hardware; for example, on a machine with 8-bit,
|
|
|
2125 16-bit, and 32-bit register modes, PRECISION might be 7, 23, or
|
|
|
2126 61. */
|
|
|
2127
|
|
|
2128 void
|
|
|
2129 set_min_and_max_values_for_integral_type (tree type,
|
|
|
2130 int precision,
|
|
|
2131 bool is_unsigned)
|
|
|
2132 {
|
|
|
2133 tree min_value;
|
|
|
2134 tree max_value;
|
|
|
2135
|
|
|
2136 if (is_unsigned)
|
|
|
2137 {
|
|
|
2138 min_value = build_int_cst (type, 0);
|
|
|
2139 max_value
|
|
|
2140 = build_int_cst_wide (type, precision - HOST_BITS_PER_WIDE_INT >= 0
|
|
|
2141 ? -1
|
|
|
2142 : ((HOST_WIDE_INT) 1 << precision) - 1,
|
|
|
2143 precision - HOST_BITS_PER_WIDE_INT > 0
|
|
|
2144 ? ((unsigned HOST_WIDE_INT) ~0
|
|
|
2145 >> (HOST_BITS_PER_WIDE_INT
|
|
|
2146 - (precision - HOST_BITS_PER_WIDE_INT)))
|
|
|
2147 : 0);
|
|
|
2148 }
|
|
|
2149 else
|
|
|
2150 {
|
|
|
2151 min_value
|
|
|
2152 = build_int_cst_wide (type,
|
|
|
2153 (precision - HOST_BITS_PER_WIDE_INT > 0
|
|
|
2154 ? 0
|
|
|
2155 : (HOST_WIDE_INT) (-1) << (precision - 1)),
|
|
|
2156 (((HOST_WIDE_INT) (-1)
|
|
|
2157 << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
|
|
|
2158 ? precision - HOST_BITS_PER_WIDE_INT - 1
|
|
|
2159 : 0))));
|
|
|
2160 max_value
|
|
|
2161 = build_int_cst_wide (type,
|
|
|
2162 (precision - HOST_BITS_PER_WIDE_INT > 0
|
|
|
2163 ? -1
|
|
|
2164 : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1),
|
|
|
2165 (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
|
|
|
2166 ? (((HOST_WIDE_INT) 1
|
|
|
2167 << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1
|
|
|
2168 : 0));
|
|
|
2169 }
|
|
|
2170
|
|
|
2171 TYPE_MIN_VALUE (type) = min_value;
|
|
|
2172 TYPE_MAX_VALUE (type) = max_value;
|
|
|
2173 }
|
|
|
2174
|
|
|
2175 /* Set the extreme values of TYPE based on its precision in bits,
|
|
|
2176 then lay it out. Used when make_signed_type won't do
|
|
|
2177 because the tree code is not INTEGER_TYPE.
|
|
|
2178 E.g. for Pascal, when the -fsigned-char option is given. */
|
|
|
2179
|
|
|
2180 void
|
|
|
2181 fixup_signed_type (tree type)
|
|
|
2182 {
|
|
|
2183 int precision = TYPE_PRECISION (type);
|
|
|
2184
|
|
|
2185 /* We can not represent properly constants greater then
|
|
|
2186 2 * HOST_BITS_PER_WIDE_INT, still we need the types
|
|
|
2187 as they are used by i386 vector extensions and friends. */
|
|
|
2188 if (precision > HOST_BITS_PER_WIDE_INT * 2)
|
|
|
2189 precision = HOST_BITS_PER_WIDE_INT * 2;
|
|
|
2190
|
|
|
2191 set_min_and_max_values_for_integral_type (type, precision,
|
|
|
2192 /*is_unsigned=*/false);
|
|
|
2193
|
|
|
2194 /* Lay out the type: set its alignment, size, etc. */
|
|
|
2195 layout_type (type);
|
|
|
2196 }
|
|
|
2197
|
|
|
2198 /* Set the extreme values of TYPE based on its precision in bits,
|
|
|
2199 then lay it out. This is used both in `make_unsigned_type'
|
|
|
2200 and for enumeral types. */
|
|
|
2201
|
|
|
2202 void
|
|
|
2203 fixup_unsigned_type (tree type)
|
|
|
2204 {
|
|
|
2205 int precision = TYPE_PRECISION (type);
|
|
|
2206
|
|
|
2207 /* We can not represent properly constants greater then
|
|
|
2208 2 * HOST_BITS_PER_WIDE_INT, still we need the types
|
|
|
2209 as they are used by i386 vector extensions and friends. */
|
|
|
2210 if (precision > HOST_BITS_PER_WIDE_INT * 2)
|
|
|
2211 precision = HOST_BITS_PER_WIDE_INT * 2;
|
|
|
2212
|
|
|
2213 TYPE_UNSIGNED (type) = 1;
|
|
|
2214
|
|
|
2215 set_min_and_max_values_for_integral_type (type, precision,
|
|
|
2216 /*is_unsigned=*/true);
|
|
|
2217
|
|
|
2218 /* Lay out the type: set its alignment, size, etc. */
|
|
|
2219 layout_type (type);
|
|
|
2220 }
|
|
|
2221
|
|
|
2222 /* Find the best machine mode to use when referencing a bit field of length
|
|
|
2223 BITSIZE bits starting at BITPOS.
|
|
|
2224
|
|
|
2225 The underlying object is known to be aligned to a boundary of ALIGN bits.
|
|
|
2226 If LARGEST_MODE is not VOIDmode, it means that we should not use a mode
|
|
|
2227 larger than LARGEST_MODE (usually SImode).
|
|
|
2228
|
|
|
2229 If no mode meets all these conditions, we return VOIDmode.
|
|
|
2230
|
|
|
2231 If VOLATILEP is false and SLOW_BYTE_ACCESS is false, we return the
|
|
|
2232 smallest mode meeting these conditions.
|
|
|
2233
|
|
|
2234 If VOLATILEP is false and SLOW_BYTE_ACCESS is true, we return the
|
|
|
2235 largest mode (but a mode no wider than UNITS_PER_WORD) that meets
|
|
|
2236 all the conditions.
|
|
|
2237
|
|
|
2238 If VOLATILEP is true the narrow_volatile_bitfields target hook is used to
|
|
|
2239 decide which of the above modes should be used. */
|
|
|
2240
|
|
|
2241 enum machine_mode
|
|
|
2242 get_best_mode (int bitsize, int bitpos, unsigned int align,
|
|
|
2243 enum machine_mode largest_mode, int volatilep)
|
|
|
2244 {
|
|
|
2245 enum machine_mode mode;
|
|
|
2246 unsigned int unit = 0;
|
|
|
2247
|
|
|
2248 /* Find the narrowest integer mode that contains the bit field. */
|
|
|
2249 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
|
|
|
2250 mode = GET_MODE_WIDER_MODE (mode))
|
|
|
2251 {
|
|
|
2252 unit = GET_MODE_BITSIZE (mode);
|
|
|
2253 if ((bitpos % unit) + bitsize <= unit)
|
|
|
2254 break;
|
|
|
2255 }
|
|
|
2256
|
|
|
2257 if (mode == VOIDmode
|
|
|
2258 /* It is tempting to omit the following line
|
|
|
2259 if STRICT_ALIGNMENT is true.
|
|
|
2260 But that is incorrect, since if the bitfield uses part of 3 bytes
|
|
|
2261 and we use a 4-byte mode, we could get a spurious segv
|
|
|
2262 if the extra 4th byte is past the end of memory.
|
|
|
2263 (Though at least one Unix compiler ignores this problem:
|
|
|
2264 that on the Sequent 386 machine. */
|
|
|
2265 || MIN (unit, BIGGEST_ALIGNMENT) > align
|
|
|
2266 || (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode)))
|
|
|
2267 return VOIDmode;
|
|
|
2268
|
|
|
2269 if ((SLOW_BYTE_ACCESS && ! volatilep)
|
|
|
2270 || (volatilep && !targetm.narrow_volatile_bitfield ()))
|
|
|
2271 {
|
|
|
2272 enum machine_mode wide_mode = VOIDmode, tmode;
|
|
|
2273
|
|
|
2274 for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode;
|
|
|
2275 tmode = GET_MODE_WIDER_MODE (tmode))
|
|
|
2276 {
|
|
|
2277 unit = GET_MODE_BITSIZE (tmode);
|
|
|
2278 if (bitpos / unit == (bitpos + bitsize - 1) / unit
|
|
|
2279 && unit <= BITS_PER_WORD
|
|
|
2280 && unit <= MIN (align, BIGGEST_ALIGNMENT)
|
|
|
2281 && (largest_mode == VOIDmode
|
|
|
2282 || unit <= GET_MODE_BITSIZE (largest_mode)))
|
|
|
2283 wide_mode = tmode;
|
|
|
2284 }
|
|
|
2285
|
|
|
2286 if (wide_mode != VOIDmode)
|
|
|
2287 return wide_mode;
|
|
|
2288 }
|
|
|
2289
|
|
|
2290 return mode;
|
|
|
2291 }
|
|
|
2292
|
|
|
2293 /* Gets minimal and maximal values for MODE (signed or unsigned depending on
|
|
|
2294 SIGN). The returned constants are made to be usable in TARGET_MODE. */
|
|
|
2295
|
|
|
2296 void
|
|
|
2297 get_mode_bounds (enum machine_mode mode, int sign,
|
|
|
2298 enum machine_mode target_mode,
|
|
|
2299 rtx *mmin, rtx *mmax)
|
|
|
2300 {
|
|
|
2301 unsigned size = GET_MODE_BITSIZE (mode);
|
|
|
2302 unsigned HOST_WIDE_INT min_val, max_val;
|
|
|
2303
|
|
|
2304 gcc_assert (size <= HOST_BITS_PER_WIDE_INT);
|
|
|
2305
|
|
|
2306 if (sign)
|
|
|
2307 {
|
|
|
2308 min_val = -((unsigned HOST_WIDE_INT) 1 << (size - 1));
|
|
|
2309 max_val = ((unsigned HOST_WIDE_INT) 1 << (size - 1)) - 1;
|
|
|
2310 }
|
|
|
2311 else
|
|
|
2312 {
|
|
|
2313 min_val = 0;
|
|
|
2314 max_val = ((unsigned HOST_WIDE_INT) 1 << (size - 1) << 1) - 1;
|
|
|
2315 }
|
|
|
2316
|
|
|
2317 *mmin = gen_int_mode (min_val, target_mode);
|
|
|
2318 *mmax = gen_int_mode (max_val, target_mode);
|
|
|
2319 }
|
|
|
2320
|
|
|
2321 #include "gt-stor-layout.h"
|
