1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441
|
/* C language support for compilation.
Copyright (C) 2014-2015 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "compile-internal.h"
#include "compile.h"
#include "gdb-dlfcn.h"
#include "c-lang.h"
#include "macrotab.h"
#include "macroscope.h"
#include "regcache.h"
/* See compile-internal.h. */
const char *
c_get_mode_for_size (int size)
{
const char *mode = NULL;
switch (size)
{
case 1:
mode = "QI";
break;
case 2:
mode = "HI";
break;
case 4:
mode = "SI";
break;
case 8:
mode = "DI";
break;
default:
internal_error (__FILE__, __LINE__, _("Invalid GCC mode size %d."), size);
}
return mode;
}
/* See compile-internal.h. */
char *
c_get_range_decl_name (const struct dynamic_prop *prop)
{
return xstrprintf ("__gdb_prop_%s", host_address_to_string (prop));
}
#define STR(x) #x
#define STRINGIFY(x) STR(x)
/* Helper function for c_get_compile_context. Open the GCC front-end
shared library and return the symbol specified by the current
GCC_C_FE_CONTEXT. */
static gcc_c_fe_context_function *
load_libcc (void)
{
void *handle;
gcc_c_fe_context_function *func;
/* gdb_dlopen will call error () on an error, so no need to check
value. */
handle = gdb_dlopen (STRINGIFY (GCC_C_FE_LIBCC));
func = (gcc_c_fe_context_function *) gdb_dlsym (handle,
STRINGIFY (GCC_C_FE_CONTEXT));
if (func == NULL)
error (_("could not find symbol %s in library %s"),
STRINGIFY (GCC_C_FE_CONTEXT),
STRINGIFY (GCC_C_FE_LIBCC));
return func;
}
/* Return the compile instance associated with the current context.
This function calls the symbol returned from the load_libcc
function. This will provide the gcc_c_context. */
struct compile_instance *
c_get_compile_context (void)
{
static gcc_c_fe_context_function *func;
struct gcc_c_context *context;
if (func == NULL)
{
func = load_libcc ();
gdb_assert (func != NULL);
}
context = (*func) (GCC_FE_VERSION_0, GCC_C_FE_VERSION_0);
if (context == NULL)
error (_("The loaded version of GCC does not support the required version "
"of the API."));
return new_compile_instance (context);
}
/* Write one macro definition. */
static void
print_one_macro (const char *name, const struct macro_definition *macro,
struct macro_source_file *source, int line,
void *user_data)
{
struct ui_file *file = (struct ui_file *) user_data;
/* Don't print command-line defines. They will be supplied another
way. */
if (line == 0)
return;
/* None of -Wno-builtin-macro-redefined, #undef first
or plain #define of the same value would avoid a warning. */
fprintf_filtered (file, "#ifndef %s\n# define %s", name, name);
if (macro->kind == macro_function_like)
{
int i;
fputs_filtered ("(", file);
for (i = 0; i < macro->argc; i++)
{
fputs_filtered (macro->argv[i], file);
if (i + 1 < macro->argc)
fputs_filtered (", ", file);
}
fputs_filtered (")", file);
}
fprintf_filtered (file, " %s\n#endif\n", macro->replacement);
}
/* Write macro definitions at PC to FILE. */
static void
write_macro_definitions (const struct block *block, CORE_ADDR pc,
struct ui_file *file)
{
struct macro_scope *scope;
if (block != NULL)
scope = sal_macro_scope (find_pc_line (pc, 0));
else
scope = default_macro_scope ();
if (scope == NULL)
scope = user_macro_scope ();
if (scope != NULL && scope->file != NULL && scope->file->table != NULL)
macro_for_each_in_scope (scope->file, scope->line, print_one_macro, file);
}
/* Helper function to construct a header scope for a block of code.
Takes a scope argument which selects the correct header to
insert into BUF. */
static void
add_code_header (enum compile_i_scope_types type, struct ui_file *buf)
{
switch (type)
{
case COMPILE_I_SIMPLE_SCOPE:
fputs_unfiltered ("void "
GCC_FE_WRAPPER_FUNCTION
" (struct "
COMPILE_I_SIMPLE_REGISTER_STRUCT_TAG
" *"
COMPILE_I_SIMPLE_REGISTER_ARG_NAME
") {\n",
buf);
break;
case COMPILE_I_PRINT_ADDRESS_SCOPE:
case COMPILE_I_PRINT_VALUE_SCOPE:
/* <string.h> is needed for a memcpy call below. */
fputs_unfiltered ("#include <string.h>\n"
"void "
GCC_FE_WRAPPER_FUNCTION
" (struct "
COMPILE_I_SIMPLE_REGISTER_STRUCT_TAG
" *"
COMPILE_I_SIMPLE_REGISTER_ARG_NAME
", "
COMPILE_I_PRINT_OUT_ARG_TYPE
" "
COMPILE_I_PRINT_OUT_ARG
") {\n",
buf);
break;
case COMPILE_I_RAW_SCOPE:
break;
default:
gdb_assert_not_reached (_("Unknown compiler scope reached."));
}
}
/* Helper function to construct a footer scope for a block of code.
Takes a scope argument which selects the correct footer to
insert into BUF. */
static void
add_code_footer (enum compile_i_scope_types type, struct ui_file *buf)
{
switch (type)
{
case COMPILE_I_SIMPLE_SCOPE:
case COMPILE_I_PRINT_ADDRESS_SCOPE:
case COMPILE_I_PRINT_VALUE_SCOPE:
fputs_unfiltered ("}\n", buf);
break;
case COMPILE_I_RAW_SCOPE:
break;
default:
gdb_assert_not_reached (_("Unknown compiler scope reached."));
}
}
/* Generate a structure holding all the registers used by the function
we're generating. */
static void
generate_register_struct (struct ui_file *stream, struct gdbarch *gdbarch,
const unsigned char *registers_used)
{
int i;
int seen = 0;
fputs_unfiltered ("struct " COMPILE_I_SIMPLE_REGISTER_STRUCT_TAG " {\n",
stream);
if (registers_used != NULL)
for (i = 0; i < gdbarch_num_regs (gdbarch); ++i)
{
if (registers_used[i])
{
struct type *regtype = check_typedef (register_type (gdbarch, i));
char *regname = compile_register_name_mangled (gdbarch, i);
struct cleanup *cleanups = make_cleanup (xfree, regname);
seen = 1;
/* You might think we could use type_print here. However,
target descriptions often use types with names like
"int64_t", which may not be defined in the inferior
(and in any case would not be looked up due to the
#pragma business). So, we take a much simpler
approach: for pointer- or integer-typed registers, emit
the field in the most direct way; and for other
register types (typically flags or vectors), emit a
maximally-aligned array of the correct size. */
fputs_unfiltered (" ", stream);
switch (TYPE_CODE (regtype))
{
case TYPE_CODE_PTR:
fprintf_filtered (stream, "__gdb_uintptr %s", regname);
break;
case TYPE_CODE_INT:
{
const char *mode
= c_get_mode_for_size (TYPE_LENGTH (regtype));
if (mode != NULL)
{
if (TYPE_UNSIGNED (regtype))
fputs_unfiltered ("unsigned ", stream);
fprintf_unfiltered (stream,
"int %s"
" __attribute__ ((__mode__(__%s__)))",
regname,
mode);
break;
}
}
/* Fall through. */
default:
fprintf_unfiltered (stream,
" unsigned char %s[%d]"
" __attribute__((__aligned__("
"__BIGGEST_ALIGNMENT__)))",
regname,
TYPE_LENGTH (regtype));
}
fputs_unfiltered (";\n", stream);
do_cleanups (cleanups);
}
}
if (!seen)
fputs_unfiltered (" char " COMPILE_I_SIMPLE_REGISTER_DUMMY ";\n",
stream);
fputs_unfiltered ("};\n\n", stream);
}
/* Take the source code provided by the user with the 'compile'
command, and compute the additional wrapping, macro, variable and
register operations needed. INPUT is the source code derived from
the 'compile' command, GDBARCH is the architecture to use when
computing above, EXPR_BLOCK denotes the block relevant contextually
to the inferior when the expression was created, and EXPR_PC
indicates the value of $PC. */
char *
c_compute_program (struct compile_instance *inst,
const char *input,
struct gdbarch *gdbarch,
const struct block *expr_block,
CORE_ADDR expr_pc)
{
struct ui_file *buf, *var_stream = NULL;
char *code;
struct cleanup *cleanup;
struct compile_c_instance *context = (struct compile_c_instance *) inst;
buf = mem_fileopen ();
cleanup = make_cleanup_ui_file_delete (buf);
write_macro_definitions (expr_block, expr_pc, buf);
/* Do not generate local variable information for "raw"
compilations. In this case we aren't emitting our own function
and the user's code may only refer to globals. */
if (inst->scope != COMPILE_I_RAW_SCOPE)
{
unsigned char *registers_used;
int i;
/* Generate the code to compute variable locations, but do it
before generating the function header, so we can define the
register struct before the function body. This requires a
temporary stream. */
var_stream = mem_fileopen ();
make_cleanup_ui_file_delete (var_stream);
registers_used = generate_c_for_variable_locations (context,
var_stream, gdbarch,
expr_block, expr_pc);
make_cleanup (xfree, registers_used);
fputs_unfiltered ("typedef unsigned int"
" __attribute__ ((__mode__(__pointer__)))"
" __gdb_uintptr;\n",
buf);
fputs_unfiltered ("typedef int"
" __attribute__ ((__mode__(__pointer__)))"
" __gdb_intptr;\n",
buf);
/* Iterate all log2 sizes in bytes supported by c_get_mode_for_size. */
for (i = 0; i < 4; ++i)
{
const char *mode = c_get_mode_for_size (1 << i);
gdb_assert (mode != NULL);
fprintf_unfiltered (buf,
"typedef int"
" __attribute__ ((__mode__(__%s__)))"
" __gdb_int_%s;\n",
mode, mode);
}
generate_register_struct (buf, gdbarch, registers_used);
}
add_code_header (inst->scope, buf);
if (inst->scope == COMPILE_I_SIMPLE_SCOPE
|| inst->scope == COMPILE_I_PRINT_ADDRESS_SCOPE
|| inst->scope == COMPILE_I_PRINT_VALUE_SCOPE)
{
ui_file_put (var_stream, ui_file_write_for_put, buf);
fputs_unfiltered ("#pragma GCC user_expression\n", buf);
}
/* The user expression has to be in its own scope, so that "extern"
works properly. Otherwise gcc thinks that the "extern"
declaration is in the same scope as the declaration provided by
gdb. */
if (inst->scope != COMPILE_I_RAW_SCOPE)
fputs_unfiltered ("{\n", buf);
fputs_unfiltered ("#line 1 \"gdb command line\"\n", buf);
switch (inst->scope)
{
case COMPILE_I_PRINT_ADDRESS_SCOPE:
case COMPILE_I_PRINT_VALUE_SCOPE:
fprintf_unfiltered (buf,
"__auto_type " COMPILE_I_EXPR_VAL " = %s;\n"
"typeof (%s) *" COMPILE_I_EXPR_PTR_TYPE ";\n"
"memcpy (" COMPILE_I_PRINT_OUT_ARG ", %s" COMPILE_I_EXPR_VAL ",\n"
"sizeof (*" COMPILE_I_EXPR_PTR_TYPE "));\n"
, input, input,
(inst->scope == COMPILE_I_PRINT_ADDRESS_SCOPE
? "&" : ""));
break;
default:
fputs_unfiltered (input, buf);
break;
}
fputs_unfiltered ("\n", buf);
/* For larger user expressions the automatic semicolons may be
confusing. */
if (strchr (input, '\n') == NULL)
fputs_unfiltered (";\n", buf);
if (inst->scope != COMPILE_I_RAW_SCOPE)
fputs_unfiltered ("}\n", buf);
add_code_footer (inst->scope, buf);
code = ui_file_xstrdup (buf, NULL);
do_cleanups (cleanup);
return code;
}
|