gcc/params.c

   1 /* params.c - Run-time parameters.
   2    Copyright (C) 2001-2016 Free Software Foundation, Inc.
   3    Written by Mark Mitchell <mark@codesourcery.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "common/common-target.h"
  25 #include "params.h"
  26 #include "params-enum.h"
  27 #include "diagnostic-core.h"
  28
  29 /* An array containing the compiler parameters and their current
  30    values.  */
  31
  32 param_info *compiler_params;
  33
  34 /* The number of entries in the table.  */
  35 static size_t num_compiler_params;
  36
  37 /* Whether the parameters have all been initialized and had their
  38    default values determined.  */
  39 static bool params_finished;
  40
  41 #define DEFPARAM(ENUM, OPTION, HELP, DEFAULT, MIN, MAX)
  42 #define DEFPARAMENUM5(ENUM, OPTION, HELP, DEFAULT, V0, V1, V2, V3, V4)  \
  43   static const char *values_ ## ENUM [] = { #V0, #V1, #V2, #V3, #V4, NULL };
  44 #include "params.def"
  45 #undef DEFPARAMENUM5
  46 #undef DEFPARAM
  47
  48 static const param_info lang_independent_params[] = {
  49 #define DEFPARAM(ENUM, OPTION, HELP, DEFAULT, MIN, MAX) \
  50   { OPTION, DEFAULT, MIN, MAX, HELP, NULL },
  51 #define DEFPARAMENUM5(ENUM, OPTION, HELP, DEFAULT,           \
  52                       V0, V1, V2, V3, V4)                    \
  53   { OPTION, (int)ENUM ## _KIND_ ## DEFAULT, 0, 4, HELP, values_ ## ENUM },
  54 #include "params.def"
  55 #undef DEFPARAM
  56 #undef DEFPARAMENUM5
  57   { NULL, 0, 0, 0, NULL, NULL }
  58 };
  59
  60 /* Add the N PARAMS to the current list of compiler parameters.  */
  61
  62 void
  63 add_params (const param_info params[], size_t n)
  64 {
  65   gcc_assert (!params_finished);
  66
  67   /* Allocate enough space for the new parameters.  */
  68   compiler_params = XRESIZEVEC (param_info, compiler_params,
  69                                 num_compiler_params + n);
  70   /* Copy them into the table.  */
  71   memcpy (compiler_params + num_compiler_params,
  72           params,
  73           n * sizeof (param_info));
  74   /* Keep track of how many parameters we have.  */
  75   num_compiler_params += n;
  76 }
  77
  78 /* Add all parameters and default values that can be set in both the
  79    driver and the compiler proper.  */
  80
  81 void
  82 global_init_params (void)
  83 {
  84   gcc_assert (!params_finished);
  85
  86   add_params (lang_independent_params, LAST_PARAM);
  87   targetm_common.option_default_params ();
  88 }
  89
  90 /* Note that all parameters have been added and all default values
  91    set.  */
  92
  93 void
  94 finish_params (void)
  95 {
  96   params_finished = true;
  97 }
  98
  99 /* Reset all state within params.c so that we can rerun the compiler
 100    within the same process.  For use by toplev::finalize.  */
 101
 102 void
 103 params_c_finalize (void)
 104 {
 105   XDELETEVEC (compiler_params);
 106   compiler_params = NULL;
 107   num_compiler_params = 0;
 108   params_finished = false;
 109 }
 110
 111 /* Set the value of the parameter given by NUM to VALUE in PARAMS and
 112    PARAMS_SET.  If EXPLICIT_P, this is being set by the user;
 113    otherwise it is being set implicitly by the compiler.  */
 114
 115 static void
 116 set_param_value_internal (compiler_param num, int value,
 117                           int *params, int *params_set,
 118                           bool explicit_p)
 119 {
 120   size_t i = (size_t) num;
 121
 122   gcc_assert (params_finished);
 123
 124   params[i] = value;
 125   if (explicit_p)
 126     params_set[i] = true;
 127 }
 128
 129 /* Return true if it can find the matching entry for NAME in the parameter
 130    table, and assign the entry index to INDEX.  Return false otherwise.  */
 131
 132 bool
 133 find_param (const char *name, enum compiler_param *index)
 134 {
 135   for (size_t i = 0; i < num_compiler_params; ++i)
 136     if (strcmp (compiler_params[i].option, name) == 0)
 137       {
 138         *index = (enum compiler_param) i;
 139         return true;
 140       }
 141
 142   return false;
 143 }
 144
 145 /* Return true if param with entry index INDEX should be defined using strings.
 146    If so, return the value corresponding to VALUE_NAME in *VALUE_P.  */
 147
 148 bool
 149 param_string_value_p (enum compiler_param index, const char *value_name,
 150                       int *value_p)
 151 {
 152   param_info *entry = &compiler_params[(int) index];
 153   if (entry->value_names == NULL)
 154     return false;
 155
 156   *value_p = -1;
 157
 158   for (int i = 0; entry->value_names[i] != NULL; ++i)
 159     if (strcmp (entry->value_names[i], value_name) == 0)
 160       {
 161         *value_p = i;
 162         return true;
 163       }
 164
 165   return true;
 166 }
 167
 168 /* Set the VALUE associated with the parameter given by NAME in PARAMS
 169    and PARAMS_SET.  */
 170
 171 void
 172 set_param_value (const char *name, int value,
 173                  int *params, int *params_set)
 174 {
 175   size_t i;
 176
 177   /* Make sure nobody tries to set a parameter to an invalid value.  */
 178   gcc_assert (value != INVALID_PARAM_VAL);
 179
 180   enum compiler_param index;
 181   if (!find_param (name, &index))
 182     {
 183       /* If we didn't find this parameter, issue an error message.  */
 184       error ("invalid parameter %qs", name);
 185       return;
 186     }
 187   i = (size_t)index;
 188
 189   if (value < compiler_params[i].min_value)
 190     error ("minimum value of parameter %qs is %u",
 191            compiler_params[i].option,
 192            compiler_params[i].min_value);
 193   else if (compiler_params[i].max_value > compiler_params[i].min_value
 194            && value > compiler_params[i].max_value)
 195     error ("maximum value of parameter %qs is %u",
 196            compiler_params[i].option,
 197            compiler_params[i].max_value);
 198   else
 199     set_param_value_internal ((compiler_param) i, value,
 200                               params, params_set, true);
 201 }
 202
 203 /* Set the value of the parameter given by NUM to VALUE in PARAMS and
 204    PARAMS_SET, implicitly, if it has not been set explicitly by the
 205    user.  */
 206
 207 void
 208 maybe_set_param_value (compiler_param num, int value,
 209                        int *params, int *params_set)
 210 {
 211   if (!params_set[(int) num])
 212     set_param_value_internal (num, value, params, params_set, false);
 213 }
 214
 215 /* Set the default value of a parameter given by NUM to VALUE, before
 216    option processing.  */
 217
 218 void
 219 set_default_param_value (compiler_param num, int value)
 220 {
 221   gcc_assert (!params_finished);
 222
 223   compiler_params[(int) num].default_value = value;
 224 }
 225
 226 /* Return the default value of parameter NUM.  */
 227
 228 int
 229 default_param_value (compiler_param num)
 230 {
 231   return compiler_params[(int) num].default_value;
 232 }
 233
 234 /* Initialize an array PARAMS with default values of the
 235    parameters.  */
 236
 237 void
 238 init_param_values (int *params)
 239 {
 240   size_t i;
 241
 242   gcc_assert (params_finished);
 243
 244   for (i = 0; i < num_compiler_params; i++)
 245     params[i] = compiler_params[i].default_value;
 246 }
 247
 248 /* Return the current value of num_compiler_params, for the benefit of
 249    plugins that use parameters as features.  */
 250
 251 size_t
 252 get_num_compiler_params (void)
 253 {
 254   return num_compiler_params;
 255 }