[PATCH 1/4] OpenMP 4.0 offloading to Intel MIC: mkoffload.

gcc/
	* config.gcc (*-intelmic-* | *-intelmicemul-*): Add i386/t-intelmic to
	tmake_file.
	(i[34567]86-*-* | x86_64-*-*): Build mkoffload$(exeext) with the
	accelerator compiler.
	* config/i386/intelmic-mkoffload.c: New file.
	* config/i386/t-intelmic: Ditto.

Co-Authored-By: Andrey Turetskiy <andrey.turetskiy@intel.com>

From-SVN: r217495

gcc/ChangeLog

+2014-11-13  Ilya Verbin  <ilya.verbin@intel.com>
+	    Andrey Turetskiy  <andrey.turetskiy@intel.com>
+
+	* config.gcc (*-intelmic-* | *-intelmicemul-*): Add i386/t-intelmic to
+	tmake_file.
+	(i[34567]86-*-* | x86_64-*-*): Build mkoffload$(exeext) with the
+	accelerator compiler.
+	* config/i386/intelmic-mkoffload.c: New file.
+	* config/i386/t-intelmic: Ditto.
+
 2014-11-13  Bernd Schmidt  <bernds@codesourcery.com>
 	    Andrey Turetskiy  <andrey.turetskiy@intel.com>
 	    Ilya Verbin  <ilya.verbin@intel.com>

gcc/config.gcc

@@ -2884,6 +2884,13 @@ powerpc*-*-* | rs6000-*-*)
 	tm_file="${tm_file} rs6000/option-defaults.h"
 esac
 
+# Build mkoffload tool
+case ${target} in
+*-intelmic-* | *-intelmicemul-*)
+	tmake_file="${tmake_file} i386/t-intelmic"
+	;;
+esac
+
 if [ "$target_has_targetcm" = "no" ]; then
   c_target_objs="$c_target_objs default-c.o"
   cxx_target_objs="$cxx_target_objs default-c.o"
@@ -4279,3 +4286,11 @@ then
 		target_cpu_default=$target_cpu_default2
 	fi
 fi
+
+case ${target} in
+i[34567]86-*-* | x86_64-*-*)
+	if test x$enable_as_accelerator = xyes; then
+		extra_programs="mkoffload\$(exeext)"
+	fi
+	;;
+esac

gcc/config/i386/intelmic-mkoffload.c

+/* Offload image generation tool for Intel MIC devices.
+
+   Copyright (C) 2014 Free Software Foundation, Inc.
+
+   Contributed by Ilya Verbin <ilya.verbin@intel.com>.
+
+   This file is part of GCC.
+
+   GCC 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, or (at your option)
+   any later version.
+
+   GCC 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 GCC; see the file COPYING3.  If not see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include <libgen.h>
+#include "system.h"
+#include "coretypes.h"
+#include "obstack.h"
+#include "intl.h"
+#include "diagnostic.h"
+#include "collect-utils.h"
+#include <libgomp_target.h>
+
+const char tool_name[] = "intelmic mkoffload";
+
+const char image_section_name[] = ".gnu.offload_images";
+const char *symbols[3] = { "__offload_image_intelmic_start",
+			   "__offload_image_intelmic_end",
+			   "__offload_image_intelmic_size" };
+const char *out_obj_filename = NULL;
+
+int num_temps = 0;
+const int MAX_NUM_TEMPS = 10;
+const char *temp_files[MAX_NUM_TEMPS];
+
+/* Shows if we should compile binaries for i386 instead of x86-64.  */
+bool target_ilp32 = false;
+
+/* Delete tempfiles and exit function.  */
+void
+tool_cleanup (bool from_signal ATTRIBUTE_UNUSED)
+{
+  for (int i = 0; i < num_temps; i++)
+    maybe_unlink (temp_files[i]);
+}
+
+static void
+mkoffload_atexit (void)
+{
+  tool_cleanup (false);
+}
+
+/* Unlink FILE unless we are debugging.  */
+void
+maybe_unlink (const char *file)
+{
+  if (debug)
+    notice ("[Leaving %s]\n", file);
+  else
+    unlink_if_ordinary (file);
+}
+
+/* Add or change the value of an environment variable, outputting the
+   change to standard error if in verbose mode.  */
+static void
+xputenv (const char *string)
+{
+  if (verbose)
+    fprintf (stderr, "%s\n", string);
+  putenv (CONST_CAST (char *, string));
+}
+
+/* Parse STR, saving found tokens into PVALUES and return their number.
+   Tokens are assumed to be delimited by ':'.  */
+static unsigned
+parse_env_var (const char *str, char ***pvalues)
+{
+  const char *curval, *nextval;
+  char **values;
+  unsigned num = 1, i;
+
+  curval = strchr (str, ':');
+  while (curval)
+    {
+      num++;
+      curval = strchr (curval + 1, ':');
+    }
+
+  values = (char **) xmalloc (num * sizeof (char *));
+  curval = str;
+  nextval = strchr (curval, ':');
+  if (nextval == NULL)
+    nextval = strchr (curval, '\0');
+
+  for (i = 0; i < num; i++)
+    {
+      int l = nextval - curval;
+      values[i] = (char *) xmalloc (l + 1);
+      memcpy (values[i], curval, l);
+      values[i][l] = 0;
+      curval = nextval + 1;
+      nextval = strchr (curval, ':');
+      if (nextval == NULL)
+	nextval = strchr (curval, '\0');
+    }
+  *pvalues = values;
+  return num;
+}
+
+/* Auxiliary function that frees elements of PTR and PTR itself.
+   N is number of elements to be freed.  If PTR is NULL, nothing is freed.
+   If an element is NULL, subsequent elements are not freed.  */
+static void
+free_array_of_ptrs (void **ptr, unsigned n)
+{
+  unsigned i;
+  if (!ptr)
+    return;
+  for (i = 0; i < n; i++)
+    {
+      if (!ptr[i])
+	break;
+      free (ptr[i]);
+    }
+  free (ptr);
+  return;
+}
+
+/* Check whether NAME can be accessed in MODE.  This is like access,
+   except that it never considers directories to be executable.  */
+static int
+access_check (const char *name, int mode)
+{
+  if (mode == X_OK)
+    {
+      struct stat st;
+
+      if (stat (name, &st) < 0 || S_ISDIR (st.st_mode))
+	return -1;
+    }
+
+  return access (name, mode);
+}
+
+/* Find target compiler using a path from COLLECT_GCC or COMPILER_PATH.  */
+static char *
+find_target_compiler (const char *name)
+{
+  bool found = false;
+  char **paths = NULL;
+  unsigned n_paths, i;
+  const char *collect_path = dirname (ASTRDUP (getenv ("COLLECT_GCC")));
+  size_t len = strlen (collect_path) + 1 + strlen (name) + 1;
+  char *target_compiler = XNEWVEC (char, len);
+  sprintf (target_compiler, "%s/%s", collect_path, name);
+  if (access_check (target_compiler, X_OK) == 0)
+    {
+      found = true;
+      goto out;
+    }
+
+  n_paths = parse_env_var (getenv ("COMPILER_PATH"), &paths);
+  for (i = 0; i < n_paths; i++)
+    {
+      len = strlen (paths[i]) + 1 + strlen (name) + 1;
+      target_compiler = XRESIZEVEC (char, target_compiler, len);
+      sprintf (target_compiler, "%s/%s", paths[i], name);
+      if (access_check (target_compiler, X_OK) == 0)
+	{
+	  found = true;
+	  break;
+	}
+    }
+
+out:
+  free_array_of_ptrs ((void **) paths, n_paths);
+  return found ? target_compiler : NULL;
+}
+
+static void
+compile_for_target (struct obstack *argv_obstack)
+{
+  if (target_ilp32)
+    obstack_ptr_grow (argv_obstack, "-m32");
+  obstack_ptr_grow (argv_obstack, NULL);
+  char **argv = XOBFINISH (argv_obstack, char **);
+
+  /* Save environment variables.  */
+  const char *epath = getenv ("GCC_EXEC_PREFIX");
+  const char *cpath = getenv ("COMPILER_PATH");
+  const char *lpath = getenv ("LIBRARY_PATH");
+  const char *rpath = getenv ("LD_RUN_PATH");
+  unsetenv ("GCC_EXEC_PREFIX");
+  unsetenv ("COMPILER_PATH");
+  unsetenv ("LIBRARY_PATH");
+  unsetenv ("LD_RUN_PATH");
+
+  fork_execute (argv[0], argv, false);
+  obstack_free (argv_obstack, NULL);
+
+  /* Restore environment variables.  */
+  xputenv (concat ("GCC_EXEC_PREFIX=", epath, NULL));
+  xputenv (concat ("COMPILER_PATH=", cpath, NULL));
+  xputenv (concat ("LIBRARY_PATH=", lpath, NULL));
+  xputenv (concat ("LD_RUN_PATH=", rpath, NULL));
+}
+
+/* Generates object file with the descriptor for the target library.  */
+static const char *
+generate_target_descr_file (const char *target_compiler)
+{
+  const char *src_filename = make_temp_file ("_target_descr.c");
+  const char *obj_filename = make_temp_file ("_target_descr.o");
+  temp_files[num_temps++] = src_filename;
+  temp_files[num_temps++] = obj_filename;
+  FILE *src_file = fopen (src_filename, "w");
+
+  if (!src_file)
+    fatal_error ("cannot open '%s'", src_filename);
+
+  fprintf (src_file,
+	   "extern void *__offload_funcs_end[];\n"
+	   "extern void *__offload_vars_end[];\n\n"
+
+	   "void *__offload_func_table[0]\n"
+	   "__attribute__ ((__used__, visibility (\"hidden\"),\n"
+	   "section (\".gnu.offload_funcs\"))) = { };\n\n"
+
+	   "void *__offload_var_table[0]\n"
+	   "__attribute__ ((__used__, visibility (\"hidden\"),\n"
+	   "section (\".gnu.offload_vars\"))) = { };\n\n"
+
+	   "void *__OFFLOAD_TARGET_TABLE__[]\n"
+	   "__attribute__ ((__used__, visibility (\"hidden\"))) = {\n"
+	   "  &__offload_func_table, &__offload_funcs_end,\n"
+	   "  &__offload_var_table, &__offload_vars_end\n"
+	   "};\n\n");
+
+  fprintf (src_file,
+	   "#ifdef __cplusplus\n"
+	   "extern \"C\"\n"
+	   "#endif\n"
+	   "void target_register_lib (const void *);\n\n"
+
+	   "__attribute__((constructor))\n"
+	   "static void\n"
+	   "init (void)\n"
+	   "{\n"
+	   "  target_register_lib (__OFFLOAD_TARGET_TABLE__);\n"
+	   "}\n");
+  fclose (src_file);
+
+  struct obstack argv_obstack;
+  obstack_init (&argv_obstack);
+  obstack_ptr_grow (&argv_obstack, target_compiler);
+  obstack_ptr_grow (&argv_obstack, "-c");
+  obstack_ptr_grow (&argv_obstack, "-shared");
+  obstack_ptr_grow (&argv_obstack, "-fPIC");
+  obstack_ptr_grow (&argv_obstack, src_filename);
+  obstack_ptr_grow (&argv_obstack, "-o");
+  obstack_ptr_grow (&argv_obstack, obj_filename);
+  compile_for_target (&argv_obstack);
+
+  return obj_filename;
+}
+
+/* Generates object file with __offload_*_end symbols for the target
+   library.  */
+static const char *
+generate_target_offloadend_file (const char *target_compiler)
+{
+  const char *src_filename = make_temp_file ("_target_offloadend.c");
+  const char *obj_filename = make_temp_file ("_target_offloadend.o");
+  temp_files[num_temps++] = src_filename;
+  temp_files[num_temps++] = obj_filename;
+  FILE *src_file = fopen (src_filename, "w");
+
+  if (!src_file)
+    fatal_error ("cannot open '%s'", src_filename);
+
+  fprintf (src_file,
+	   "void *__offload_funcs_end[0]\n"
+	   "__attribute__ ((__used__, visibility (\"hidden\"),\n"
+	   "section (\".gnu.offload_funcs\"))) = { };\n\n"
+
+	   "void *__offload_vars_end[0]\n"
+	   "__attribute__ ((__used__, visibility (\"hidden\"),\n"
+	   "section (\".gnu.offload_vars\"))) = { };\n");
+  fclose (src_file);
+
+  struct obstack argv_obstack;
+  obstack_init (&argv_obstack);
+  obstack_ptr_grow (&argv_obstack, target_compiler);
+  obstack_ptr_grow (&argv_obstack, "-c");
+  obstack_ptr_grow (&argv_obstack, "-shared");
+  obstack_ptr_grow (&argv_obstack, "-fPIC");
+  obstack_ptr_grow (&argv_obstack, src_filename);
+  obstack_ptr_grow (&argv_obstack, "-o");
+  obstack_ptr_grow (&argv_obstack, obj_filename);
+  compile_for_target (&argv_obstack);
+
+  return obj_filename;
+}
+
+/* Generates object file with the host side descriptor.  */
+static const char *
+generate_host_descr_file (const char *host_compiler)
+{
+  const char *src_filename = make_temp_file ("_host_descr.c");
+  const char *obj_filename = make_temp_file ("_host_descr.o");
+  temp_files[num_temps++] = src_filename;
+  temp_files[num_temps++] = obj_filename;
+  FILE *src_file = fopen (src_filename, "w");
+
+  if (!src_file)
+    fatal_error ("cannot open '%s'", src_filename);
+
+  fprintf (src_file,
+	   "extern void *__OFFLOAD_TABLE__;\n"
+	   "extern void *__offload_image_intelmic_start;\n"
+	   "extern void *__offload_image_intelmic_end;\n\n"
+
+	   "static const void *__offload_target_data[] = {\n"
+	   "  &__offload_image_intelmic_start, &__offload_image_intelmic_end\n"
+	   "};\n\n");
+
+  fprintf (src_file,
+	   "#ifdef __cplusplus\n"
+	   "extern \"C\"\n"
+	   "#endif\n"
+	   "void GOMP_offload_register (void *, int, void *);\n\n"
+
+	   "__attribute__((constructor))\n"
+	   "static void\n"
+	   "init (void)\n"
+	   "{\n"
+	   "  GOMP_offload_register (&__OFFLOAD_TABLE__, %d, __offload_target_data);\n"
+	   "}\n", OFFLOAD_TARGET_TYPE_INTEL_MIC);
+  fclose (src_file);
+
+  unsigned new_argc = 0;
+  const char *new_argv[9];
+  new_argv[new_argc++] = host_compiler;
+  new_argv[new_argc++] = "-c";
+  new_argv[new_argc++] = "-fPIC";
+  new_argv[new_argc++] = "-shared";
+  if (target_ilp32)
+    new_argv[new_argc++] = "-m32";
+  new_argv[new_argc++] = src_filename;
+  new_argv[new_argc++] = "-o";
+  new_argv[new_argc++] = obj_filename;
+  new_argv[new_argc++] = NULL;
+
+  fork_execute (new_argv[0], CONST_CAST (char **, new_argv), false);
+
+  return obj_filename;
+}
+
+static const char *
+prepare_target_image (const char *target_compiler, int argc, char **argv)
+{
+  const char *target_descr_filename
+    = generate_target_descr_file (target_compiler);
+  const char *target_offloadend_filename
+    = generate_target_offloadend_file (target_compiler);
+
+  char *opt1
+    = XALLOCAVEC (char, sizeof ("-Wl,") + strlen (target_descr_filename));
+  char *opt2
+    = XALLOCAVEC (char, sizeof ("-Wl,") + strlen (target_offloadend_filename));
+  sprintf (opt1, "-Wl,%s", target_descr_filename);
+  sprintf (opt2, "-Wl,%s", target_offloadend_filename);
+
+  const char *target_so_filename = make_temp_file ("_offload_intelmic.so");
+  temp_files[num_temps++] = target_so_filename;
+  struct obstack argv_obstack;
+  obstack_init (&argv_obstack);
+  obstack_ptr_grow (&argv_obstack, target_compiler);
+  obstack_ptr_grow (&argv_obstack, "-xlto");
+  obstack_ptr_grow (&argv_obstack, "-fopenmp");
+  obstack_ptr_grow (&argv_obstack, "-shared");
+  obstack_ptr_grow (&argv_obstack, "-fPIC");
+  obstack_ptr_grow (&argv_obstack, opt1);
+  for (int i = 1; i < argc; i++)
+    {
+      if (!strcmp (argv[i], "-o") && i + 1 != argc)
+	out_obj_filename = argv[++i];
+      else
+	obstack_ptr_grow (&argv_obstack, argv[i]);
+    }
+  if (!out_obj_filename)
+    fatal_error ("output file not specified");
+  obstack_ptr_grow (&argv_obstack, opt2);
+  obstack_ptr_grow (&argv_obstack, "-o");
+  obstack_ptr_grow (&argv_obstack, target_so_filename);
+  compile_for_target (&argv_obstack);
+
+  /* Run objcopy.  */
+  char *rename_section_opt
+    = XALLOCAVEC (char, sizeof (".data=") + strlen (image_section_name));
+  sprintf (rename_section_opt, ".data=%s", image_section_name);
+  const char *objcopy_argv[11];
+  objcopy_argv[0] = "objcopy";
+  objcopy_argv[1] = "-B";
+  objcopy_argv[2] = "i386";
+  objcopy_argv[3] = "-I";
+  objcopy_argv[4] = "binary";
+  objcopy_argv[5] = "-O";
+  if (target_ilp32)
+    objcopy_argv[6] = "elf32-i386";
+  else
+    objcopy_argv[6] = "elf64-x86-64";
+  objcopy_argv[7] = target_so_filename;
+  objcopy_argv[8] = "--rename-section";
+  objcopy_argv[9] = rename_section_opt;
+  objcopy_argv[10] = NULL;
+  fork_execute (objcopy_argv[0], CONST_CAST (char **, objcopy_argv), false);
+
+  /* Objcopy has created symbols, containing the input file name with
+     special characters replaced with '_'.  We are going to rename these
+     new symbols.  */
+  size_t symbol_name_len = strlen (target_so_filename);
+  char *symbol_name = XALLOCAVEC (char, symbol_name_len + 1);
+  for (size_t i = 0; i <= symbol_name_len; i++)
+    {
+      char c = target_so_filename[i];
+      if ((c == '/') || (c == '.'))
+	c = '_';
+      symbol_name[i] = c;
+    }
+
+  char *opt_for_objcopy[3];
+  opt_for_objcopy[0] = XALLOCAVEC (char, sizeof ("_binary__start=")
+					 + symbol_name_len
+					 + strlen (symbols[0]));
+  opt_for_objcopy[1] = XALLOCAVEC (char, sizeof ("_binary__end=")
+					 + symbol_name_len
+					 + strlen (symbols[1]));
+  opt_for_objcopy[2] = XALLOCAVEC (char, sizeof ("_binary__size=")
+					 + symbol_name_len
+					 + strlen (symbols[2]));
+  sprintf (opt_for_objcopy[0], "_binary_%s_start=%s", symbol_name, symbols[0]);
+  sprintf (opt_for_objcopy[1], "_binary_%s_end=%s", symbol_name, symbols[1]);
+  sprintf (opt_for_objcopy[2], "_binary_%s_size=%s", symbol_name, symbols[2]);
+
+  objcopy_argv[0] = "objcopy";
+  objcopy_argv[1] = target_so_filename;
+  objcopy_argv[2] = "--redefine-sym";
+  objcopy_argv[3] = opt_for_objcopy[0];
+  objcopy_argv[4] = "--redefine-sym";
+  objcopy_argv[5] = opt_for_objcopy[1];
+  objcopy_argv[6] = "--redefine-sym";
+  objcopy_argv[7] = opt_for_objcopy[2];
+  objcopy_argv[8] = NULL;
+  fork_execute (objcopy_argv[0], CONST_CAST (char **, objcopy_argv), false);
+
+  return target_so_filename;
+}
+
+int
+main (int argc, char **argv)
+{
+  progname = "mkoffload-intelmic";
+  gcc_init_libintl ();
+  diagnostic_initialize (global_dc, 0);
+
+  if (atexit (mkoffload_atexit) != 0)
+    fatal_error ("atexit failed");
+
+  const char *host_compiler = getenv ("COLLECT_GCC");
+  if (!host_compiler)
+    fatal_error ("COLLECT_GCC must be set");
+
+  const char *target_driver_name
+    = DEFAULT_REAL_TARGET_MACHINE "-accel-" DEFAULT_TARGET_MACHINE "-gcc";
+  char *target_compiler = find_target_compiler (target_driver_name);
+  if (target_compiler == NULL)
+    fatal_error ("offload compiler %s not found", target_driver_name);
+
+  /* We may be called with all the arguments stored in some file and
+     passed with @file.  Expand them into argv before processing.  */
+  expandargv (&argc, &argv);
+
+  /* Find out whether we should compile binaries for i386 or x86-64.  */
+  for (int i = argc - 1; i > 0; i--)
+    if (strncmp (argv[i], "-foffload-abi=", sizeof ("-foffload-abi=") - 1) == 0)
+      {
+	if (strstr (argv[i], "ilp32"))
+	  target_ilp32 = true;
+	else if (!strstr (argv[i], "lp64"))
+	  fatal_error ("unrecognizable argument of option -foffload-abi");
+	break;
+      }
+
+  const char *target_so_filename
+    = prepare_target_image (target_compiler, argc, argv);
+
+  const char *host_descr_filename = generate_host_descr_file (host_compiler);
+
+  /* Perform partial linking for the target image and host side descriptor.
+     As a result we'll get a finalized object file with all offload data.  */
+  unsigned new_argc = 0;
+  const char *new_argv[9];
+  new_argv[new_argc++] = "ld";
+  if (target_ilp32)
+    {
+      new_argv[new_argc++] = "-m";
+      new_argv[new_argc++] = "elf_i386";
+    }
+  new_argv[new_argc++] = "--relocatable";
+  new_argv[new_argc++] = host_descr_filename;
+  new_argv[new_argc++] = target_so_filename;
+  new_argv[new_argc++] = "-o";
+  new_argv[new_argc++] = out_obj_filename;
+  new_argv[new_argc++] = NULL;
+  fork_execute (new_argv[0], CONST_CAST (char **, new_argv), false);
+
+  /* Run objcopy on the resultant object file to localize generated symbols
+     to avoid conflicting between different DSO and an executable.  */
+  new_argv[0] = "objcopy";
+  new_argv[1] = "-L";
+  new_argv[2] = symbols[0];
+  new_argv[3] = "-L";
+  new_argv[4] = symbols[1];
+  new_argv[5] = "-L";
+  new_argv[6] = symbols[2];
+  new_argv[7] = out_obj_filename;
+  new_argv[8] = NULL;
+  fork_execute (new_argv[0], CONST_CAST (char **, new_argv), false);
+
+  return 0;
+}

gcc/config/i386/t-intelmic

+mkoffload.o: $(srcdir)/config/i386/intelmic-mkoffload.c | insn-modes.h
+	$(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) \
+	  -I$(srcdir)/../libgomp \
+	  -DDEFAULT_REAL_TARGET_MACHINE=\"$(real_target_noncanonical)\" \
+	  -DDEFAULT_TARGET_MACHINE=\"$(target_noncanonical)\" \
+	  $< $(OUTPUT_OPTION)
+
+mkoffload$(exeext): mkoffload.o collect-utils.o libcommon-target.a $(LIBIBERTY) $(LIBDEPS)
+	$(COMPILER) -o $@ mkoffload.o collect-utils.o libcommon-target.a $(LIBIBERTY) $(LIBS)