[deliverable/binutils-gdb.git] / gdb / compile / compile-c-support.c

/* 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));
}

\f

#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);
}

\f

/* 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;
}
Commit	Line	Data
bb2ec1b3 TT	1	/* C language support for compilation.
bb2ec1b3 TT	2
32d0add0	3	Copyright (C) 2014-2015 Free Software Foundation, Inc.
bb2ec1b3 TT	4
	5	This file is part of GDB.
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 3 of the License, or
	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program. If not, see <http://www.gnu.org/licenses/>. */
	19
	20	#include "defs.h"
	21	#include "compile-internal.h"
	22	#include "compile.h"
	23	#include "gdb-dlfcn.h"
	24	#include "c-lang.h"
	25	#include "macrotab.h"
	26	#include "macroscope.h"
	27	#include "regcache.h"
	28
	29	/* See compile-internal.h. */
	30
	31	const char *
	32	c_get_mode_for_size (int size)
	33	{
	34	const char *mode = NULL;
	35
	36	switch (size)
	37	{
	38	case 1:
	39	mode = "QI";
	40	break;
	41	case 2:
	42	mode = "HI";
	43	break;
	44	case 4:
	45	mode = "SI";
	46	break;
	47	case 8:
	48	mode = "DI";
	49	break;
	50	default:
	51	internal_error (__FILE__, __LINE__, _("Invalid GCC mode size %d."), size);
	52	}
	53
	54	return mode;
	55	}
	56
	57	/* See compile-internal.h. */
	58
	59	char *
	60	c_get_range_decl_name (const struct dynamic_prop *prop)
	61	{
	62	return xstrprintf ("__gdb_prop_%s", host_address_to_string (prop));
	63	}
	64
	65	\f
	66
	67	#define STR(x) #x
68	#define STRINGIFY(x) STR(x)
69
70	/* Helper function for c_get_compile_context. Open the GCC front-end
71	shared library and return the symbol specified by the current
72	GCC_C_FE_CONTEXT. */
73
74	static gcc_c_fe_context_function *
75	load_libcc (void)
76	{
77	void *handle;
78	gcc_c_fe_context_function *func;
79
80	/* gdb_dlopen will call error () on an error, so no need to check
81	value. */
82	handle = gdb_dlopen (STRINGIFY (GCC_C_FE_LIBCC));
83	func = (gcc_c_fe_context_function *) gdb_dlsym (handle,
84	STRINGIFY (GCC_C_FE_CONTEXT));
85
86	if (func == NULL)
87	error (_("could not find symbol %s in library %s"),
88	STRINGIFY (GCC_C_FE_CONTEXT),
89	STRINGIFY (GCC_C_FE_LIBCC));
90	return func;
91	}
92
93	/* Return the compile instance associated with the current context.
94	This function calls the symbol returned from the load_libcc
95	function. This will provide the gcc_c_context. */
96
97	struct compile_instance *
98	c_get_compile_context (void)
99	{
100	static gcc_c_fe_context_function *func;
101
102	struct gcc_c_context *context;
103
104	if (func == NULL)
105	{
106	func = load_libcc ();
107	gdb_assert (func != NULL);
108	}
109
110	context = (*func) (GCC_FE_VERSION_0, GCC_C_FE_VERSION_0);
111	if (context == NULL)
112	error (_("The loaded version of GCC does not support the required version "
113	"of the API."));
114
115	return new_compile_instance (context);
116	}
117
118	\f
119
120	/* Write one macro definition. */
121
122	static void
123	print_one_macro (const char name, const struct macro_definition macro,
124	struct macro_source_file *source, int line,
125	void *user_data)
126	{
9a3c8263	127	struct ui_file file = (struct ui_file ) user_data;
bb2ec1b3 TT	128
	129	/* Don't print command-line defines. They will be supplied another
	130	way. */
	131	if (line == 0)
	132	return;
	133
3a9558c4 JK	134	/* None of -Wno-builtin-macro-redefined, #undef first
	135	or plain #define of the same value would avoid a warning. */
	136	fprintf_filtered (file, "#ifndef %s\n# define %s", name, name);
bb2ec1b3 TT	137
	138	if (macro->kind == macro_function_like)
	139	{
	140	int i;
	141
	142	fputs_filtered ("(", file);
	143	for (i = 0; i < macro->argc; i++)
	144	{
	145	fputs_filtered (macro->argv[i], file);
	146	if (i + 1 < macro->argc)
	147	fputs_filtered (", ", file);
	148	}
	149	fputs_filtered (")", file);
	150	}
	151
3a9558c4	152	fprintf_filtered (file, " %s\n#endif\n", macro->replacement);
bb2ec1b3 TT	153	}
	154
	155	/* Write macro definitions at PC to FILE. */
	156
	157	static void
	158	write_macro_definitions (const struct block *block, CORE_ADDR pc,
	159	struct ui_file *file)
	160	{
	161	struct macro_scope *scope;
	162
	163	if (block != NULL)
	164	scope = sal_macro_scope (find_pc_line (pc, 0));
	165	else
	166	scope = default_macro_scope ();
	167	if (scope == NULL)
	168	scope = user_macro_scope ();
	169
	170	if (scope != NULL && scope->file != NULL && scope->file->table != NULL)
	171	macro_for_each_in_scope (scope->file, scope->line, print_one_macro, file);
	172	}
	173
	174	/* Helper function to construct a header scope for a block of code.
	175	Takes a scope argument which selects the correct header to
	176	insert into BUF. */
	177
	178	static void
	179	add_code_header (enum compile_i_scope_types type, struct ui_file *buf)
	180	{
	181	switch (type)
	182	{
	183	case COMPILE_I_SIMPLE_SCOPE:
	184	fputs_unfiltered ("void "
	185	GCC_FE_WRAPPER_FUNCTION
	186	" (struct "
	187	COMPILE_I_SIMPLE_REGISTER_STRUCT_TAG
	188	" *"
	189	COMPILE_I_SIMPLE_REGISTER_ARG_NAME
	190	") {\n",
	191	buf);
	192	break;
36de76f9 JK	193	case COMPILE_I_PRINT_ADDRESS_SCOPE:
	194	case COMPILE_I_PRINT_VALUE_SCOPE:
	195	/* <string.h> is needed for a memcpy call below. */
	196	fputs_unfiltered ("#include <string.h>\n"
	197	"void "
	198	GCC_FE_WRAPPER_FUNCTION
	199	" (struct "
	200	COMPILE_I_SIMPLE_REGISTER_STRUCT_TAG
	201	" *"
	202	COMPILE_I_SIMPLE_REGISTER_ARG_NAME
	203	", "
	204	COMPILE_I_PRINT_OUT_ARG_TYPE
	205	" "
	206	COMPILE_I_PRINT_OUT_ARG
	207	") {\n",
	208	buf);
	209	break;
	210
bb2ec1b3 TT	211	case COMPILE_I_RAW_SCOPE:
	212	break;
	213	default:
	214	gdb_assert_not_reached (_("Unknown compiler scope reached."));
	215	}
	216	}
	217
	218	/* Helper function to construct a footer scope for a block of code.
	219	Takes a scope argument which selects the correct footer to
	220	insert into BUF. */
	221
	222	static void
	223	add_code_footer (enum compile_i_scope_types type, struct ui_file *buf)
	224	{
	225	switch (type)
	226	{
	227	case COMPILE_I_SIMPLE_SCOPE:
36de76f9 JK	228	case COMPILE_I_PRINT_ADDRESS_SCOPE:
36de76f9 JK	229	case COMPILE_I_PRINT_VALUE_SCOPE:
bb2ec1b3 TT	230	fputs_unfiltered ("}\n", buf);
	231	break;
	232	case COMPILE_I_RAW_SCOPE:
	233	break;
	234	default:
	235	gdb_assert_not_reached (_("Unknown compiler scope reached."));
	236	}
	237	}
	238
	239	/* Generate a structure holding all the registers used by the function
	240	we're generating. */
	241
	242	static void
	243	generate_register_struct (struct ui_file stream, struct gdbarch gdbarch,
	244	const unsigned char *registers_used)
	245	{
	246	int i;
	247	int seen = 0;
	248
	249	fputs_unfiltered ("struct " COMPILE_I_SIMPLE_REGISTER_STRUCT_TAG " {\n",
	250	stream);
	251
	252	if (registers_used != NULL)
	253	for (i = 0; i < gdbarch_num_regs (gdbarch); ++i)
	254	{
	255	if (registers_used[i])
	256	{
	257	struct type *regtype = check_typedef (register_type (gdbarch, i));
	258	char *regname = compile_register_name_mangled (gdbarch, i);
	259	struct cleanup *cleanups = make_cleanup (xfree, regname);
	260
	261	seen = 1;
	262
	263	/* You might think we could use type_print here. However,
	264	target descriptions often use types with names like
	265	"int64_t", which may not be defined in the inferior
	266	(and in any case would not be looked up due to the
	267	#pragma business). So, we take a much simpler
	268	approach: for pointer- or integer-typed registers, emit
	269	the field in the most direct way; and for other
	270	register types (typically flags or vectors), emit a
	271	maximally-aligned array of the correct size. */
	272
	273	fputs_unfiltered (" ", stream);
	274	switch (TYPE_CODE (regtype))
	275	{
	276	case TYPE_CODE_PTR:
3a9558c4	277	fprintf_filtered (stream, "__gdb_uintptr %s", regname);
bb2ec1b3 TT	278	break;
	279
	280	case TYPE_CODE_INT:
	281	{
	282	const char *mode
	283	= c_get_mode_for_size (TYPE_LENGTH (regtype));
	284
	285	if (mode != NULL)
	286	{
	287	if (TYPE_UNSIGNED (regtype))
	288	fputs_unfiltered ("unsigned ", stream);
	289	fprintf_unfiltered (stream,
	290	"int %s"
	291	" __attribute__ ((__mode__(__%s__)))",
	292	regname,
	293	mode);
	294	break;
	295	}
	296	}
	297
	298	/* Fall through. */
	299
	300	default:
	301	fprintf_unfiltered (stream,
	302	" unsigned char %s[%d]"
	303	" __attribute__((__aligned__("
	304	"__BIGGEST_ALIGNMENT__)))",
	305	regname,
	306	TYPE_LENGTH (regtype));
	307	}
	308	fputs_unfiltered (";\n", stream);
	309
	310	do_cleanups (cleanups);
	311	}
	312	}
	313
	314	if (!seen)
	315	fputs_unfiltered (" char " COMPILE_I_SIMPLE_REGISTER_DUMMY ";\n",
	316	stream);
	317
	318	fputs_unfiltered ("};\n\n", stream);
	319	}
	320
	321	/* Take the source code provided by the user with the 'compile'
	322	command, and compute the additional wrapping, macro, variable and
	323	register operations needed. INPUT is the source code derived from
	324	the 'compile' command, GDBARCH is the architecture to use when
	325	computing above, EXPR_BLOCK denotes the block relevant contextually
	326	to the inferior when the expression was created, and EXPR_PC
	327	indicates the value of $PC. */
	328
	329	char *
	330	c_compute_program (struct compile_instance *inst,
	331	const char *input,
	332	struct gdbarch *gdbarch,
	333	const struct block *expr_block,
	334	CORE_ADDR expr_pc)
	335	{
	336	struct ui_file buf, var_stream = NULL;
	337	char *code;
	338	struct cleanup *cleanup;
	339	struct compile_c_instance context = (struct compile_c_instance ) inst;
	340
	341	buf = mem_fileopen ();
342	cleanup = make_cleanup_ui_file_delete (buf);
343
344	write_macro_definitions (expr_block, expr_pc, buf);
345
346	/* Do not generate local variable information for "raw"
347	compilations. In this case we aren't emitting our own function
348	and the user's code may only refer to globals. */
349	if (inst->scope != COMPILE_I_RAW_SCOPE)
350	{
351	unsigned char *registers_used;
352	int i;
353
354	/* Generate the code to compute variable locations, but do it
355	before generating the function header, so we can define the
356	register struct before the function body. This requires a
357	temporary stream. */
358	var_stream = mem_fileopen ();
359	make_cleanup_ui_file_delete (var_stream);
360	registers_used = generate_c_for_variable_locations (context,
361	var_stream, gdbarch,
362	expr_block, expr_pc);
363	make_cleanup (xfree, registers_used);
364
bb2ec1b3 TT	365	fputs_unfiltered ("typedef unsigned int"
	366	" __attribute__ ((__mode__(__pointer__)))"
	367	" __gdb_uintptr;\n",
	368	buf);
	369	fputs_unfiltered ("typedef int"
	370	" __attribute__ ((__mode__(__pointer__)))"
	371	" __gdb_intptr;\n",
	372	buf);
	373
bb2b33b9	374	/* Iterate all log2 sizes in bytes supported by c_get_mode_for_size. */
bb2ec1b3 TT	375	for (i = 0; i < 4; ++i)
	376	{
	377	const char *mode = c_get_mode_for_size (1 << i);
	378
	379	gdb_assert (mode != NULL);
	380	fprintf_unfiltered (buf,
	381	"typedef int"
	382	" __attribute__ ((__mode__(__%s__)))"
	383	" __gdb_int_%s;\n",
	384	mode, mode);
	385	}
3a9558c4 JK	386
3a9558c4 JK	387	generate_register_struct (buf, gdbarch, registers_used);
bb2ec1b3 TT	388	}
	389
	390	add_code_header (inst->scope, buf);
	391
36de76f9 JK	392	if (inst->scope == COMPILE_I_SIMPLE_SCOPE
	393	\|\| inst->scope == COMPILE_I_PRINT_ADDRESS_SCOPE
	394	\|\| inst->scope == COMPILE_I_PRINT_VALUE_SCOPE)
bb2ec1b3 TT	395	{
	396	ui_file_put (var_stream, ui_file_write_for_put, buf);
	397	fputs_unfiltered ("#pragma GCC user_expression\n", buf);
	398	}
	399
	400	/* The user expression has to be in its own scope, so that "extern"
	401	works properly. Otherwise gcc thinks that the "extern"
	402	declaration is in the same scope as the declaration provided by
	403	gdb. */
	404	if (inst->scope != COMPILE_I_RAW_SCOPE)
	405	fputs_unfiltered ("{\n", buf);
	406
	407	fputs_unfiltered ("#line 1 \"gdb command line\"\n", buf);
36de76f9 JK	408
	409	switch (inst->scope)
	410	{
	411	case COMPILE_I_PRINT_ADDRESS_SCOPE:
	412	case COMPILE_I_PRINT_VALUE_SCOPE:
	413	fprintf_unfiltered (buf,
	414	"__auto_type " COMPILE_I_EXPR_VAL " = %s;\n"
	415	"typeof (%s) *" COMPILE_I_EXPR_PTR_TYPE ";\n"
	416	"memcpy (" COMPILE_I_PRINT_OUT_ARG ", %s" COMPILE_I_EXPR_VAL ",\n"
	417	"sizeof (*" COMPILE_I_EXPR_PTR_TYPE "));\n"
	418	, input, input,
	419	(inst->scope == COMPILE_I_PRINT_ADDRESS_SCOPE
	420	? "&" : ""));
	421	break;
	422	default:
	423	fputs_unfiltered (input, buf);
	424	break;
	425	}
	426
bb2ec1b3 TT	427	fputs_unfiltered ("\n", buf);
	428
	429	/* For larger user expressions the automatic semicolons may be
	430	confusing. */
	431	if (strchr (input, '\n') == NULL)
	432	fputs_unfiltered (";\n", buf);
	433
	434	if (inst->scope != COMPILE_I_RAW_SCOPE)
	435	fputs_unfiltered ("}\n", buf);
	436
	437	add_code_footer (inst->scope, buf);
	438	code = ui_file_xstrdup (buf, NULL);
	439	do_cleanups (cleanup);
	440	return code;
	441	}