diff mbox

nvptx offloading patches [4/n]

Message ID 5454CDF1.3070307@codesourcery.com
State New
Headers show

Commit Message

Bernd Schmidt Nov. 1, 2014, 12:11 p.m. UTC
I'm sending this for reference more than anything else - this is the 
patch that adds the target support for offloading to the nvptx port. It 
depends on the other offloading patches Ilya is currently submitting.

I actually expect this to change a little in the near future; the nvptx 
mkoffload duplicates some of the logic that we have in nvptx-as and I'm 
thinking of making some improvements. But I figure it would be good to 
show the entire picture, as it is as of now.


Bernd
diff mbox

Patch

Index: git/gcc/config/nvptx/mkoffload.c
===================================================================
--- /dev/null
+++ git/gcc/config/nvptx/mkoffload.c
@@ -0,0 +1,889 @@ 
+/* Offload image generation tool for ptx
+
+   Nathan Sidwell <nathan@codesourcery.com>
+   Bernd Schmidt <bernds@codesourcery.com>
+
+   Munges PTX assembly into a C source file defining the PTX code as a
+   string.
+
+   This is not a complete assembler.  We presume the source is well
+   formed from the compiler and can die horribly if it is not.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "intl.h"
+#include <libgen.h>
+#include "obstack.h"
+#include "diagnostic-core.h"
+#include "collect-utils.h"
+
+const char tool_name[] = "nvptx mkoffload";
+
+#define COMMENT_PREFIX "#"
+
+typedef enum Kind
+{
+  /* 0-ff used for single char tokens */
+  K_symbol = 0x100, /* a symbol */
+  K_label,  /* a label defn (i.e. symbol:) */
+  K_ident,  /* other ident */
+  K_dotted, /* dotted identifier */
+  K_number,
+  K_string,
+  K_comment
+} Kind;
+
+typedef struct Token
+{
+  unsigned short kind : 12;
+  unsigned short space : 1; /* preceded by space */
+  unsigned short end : 1;   /* succeeded by end of line */
+  /* Length of token */
+  unsigned short len;
+
+  /* Token itself */
+  char const *ptr;
+} Token;
+
+/* statement info */
+typedef enum Vis
+{
+  V_dot = 0,  /* random pseudo */
+  V_var = 1,  /* var decl/defn */
+  V_func = 2, /* func decl/defn */
+  V_insn = 3, /* random insn */
+  V_label = 4, /* label defn */
+  V_comment = 5,
+  V_pred = 6,  /* predicate */
+  V_mask = 0x7,
+  V_global = 0x08, /* globalize */
+  V_weak = 0x10,   /* weakly globalize */
+  V_no_eol = 0x20, /* no end of line */
+  V_prefix_comment = 0x40 /* prefixed comment */
+} Vis;
+
+typedef struct Stmt
+{
+  struct Stmt *next;
+  Token *tokens;
+  unsigned char vis;
+  unsigned len : 12;
+  unsigned sym : 12;
+} Stmt;
+
+struct id_map
+{
+  id_map *next;
+  char *ptx_name;
+};
+
+static const char *read_file (FILE *);
+static Token *tokenize (const char *);
+
+static void write_token (FILE *, const Token *);
+static void write_tokens (FILE *, const Token *, unsigned, int);
+
+static Stmt *alloc_stmt (unsigned, Token *, Token *, const Token *);
+#define alloc_comment(S,E) alloc_stmt (V_comment, S, E, 0)
+#define append_stmt(V, S) ((S)->next = *(V), *(V) = (S))
+static Stmt *rev_stmts (Stmt *);
+static void write_stmt (FILE *, const Stmt *);
+static void write_stmts (FILE *, const Stmt *);
+
+static Token *parse_insn (Token *);
+static Token *parse_list_nosemi (Token *);
+static Token *parse_init (Token *);
+static Token *parse_file (Token *);
+
+static Stmt *decls;
+static Stmt *vars;
+static Stmt *fns;
+
+static id_map *func_ids, **funcs_tail = &func_ids;
+static id_map *var_ids, **vars_tail = &var_ids;
+
+/* Files to unlink.  */
+static const char *ptx_name;
+static const char *ptx_cfile_name;
+
+/* Delete tempfiles.  */
+
+/* Unlink a temporary file unless requested otherwise.  */
+
+void
+maybe_unlink (const char *file)
+{
+  if (! debug)
+    {
+      if (unlink_if_ordinary (file)
+	  && errno != ENOENT)
+	fatal_error ("deleting file %s: %m", file);
+    }
+  else
+    fprintf (stderr, "[Leaving %s]\n", file);
+}
+
+void
+tool_cleanup (bool)
+{
+}
+
+/* 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));
+}
+
+
+static void
+record_id (const char *p1, id_map ***where)
+{
+  const char *end = strchr (p1, '\n');
+  if (!end)
+    fatal_error ("malformed ptx file");
+
+  id_map *v = XNEW (id_map);
+  size_t len = end - p1;
+  v->ptx_name = XNEWVEC (char, len + 1);
+  memcpy (v->ptx_name, p1, len);
+  v->ptx_name[len] = '\0';
+  v->next = NULL;
+  id_map **tail = *where;
+  *tail = v;
+  *where = &v->next;
+}
+
+/* Read the whole input file.  It will be NUL terminated (but
+   remember, there could be a NUL in the file itself.  */
+
+static const char *
+read_file (FILE *stream)
+{
+  size_t alloc = 16384;
+  size_t base = 0;
+  char *buffer;
+
+  if (!fseek (stream, 0, SEEK_END))
+    {
+      /* Get the file size.  */
+      long s = ftell (stream);
+      if (s >= 0)
+	alloc = s + 100;
+      fseek (stream, 0, SEEK_SET);
+    }
+  buffer = XNEWVEC (char, alloc);
+
+  for (;;)
+    {
+      size_t n = fread (buffer + base, 1, alloc - base - 1, stream);
+
+      if (!n)
+	break;
+      base += n;
+      if (base + 1 == alloc)
+	{
+	  alloc *= 2;
+	  buffer = XRESIZEVEC (char, buffer, alloc);
+	}
+    }
+  buffer[base] = 0;
+  return buffer;
+}
+
+/* Read a token, advancing ptr.
+   If we read a comment, append it to the comments block. */
+
+static Token *
+tokenize (const char *ptr)
+{
+  unsigned alloc = 1000;
+  unsigned num = 0;
+  Token *toks = XNEWVEC (Token, alloc);
+  int in_comment = 0;
+  int not_comment = 0;
+
+  for (;; num++)
+    {
+      const char *base;
+      unsigned kind;
+      int ws = 0;
+      int eol = 0;
+
+    again:
+      base = ptr;
+      if (in_comment)
+	goto block_comment;
+      switch (kind = *ptr++)
+	{
+	default:
+	  break;
+
+	case '\n':
+	  eol = 1;
+	  /* Fall through */
+	case ' ':
+	case '\t':
+	case '\r':
+	case '\v':
+	  /* White space */
+	  ws = not_comment;
+	  goto again;
+
+	case '/':
+	  {
+	    if (*ptr == '/')
+	      {
+		/* line comment.  Do not include trailing \n */
+		base += 2;
+		for (; *ptr; ptr++)
+		  if (*ptr == '\n')
+		    break;
+		kind = K_comment;
+	      }
+	    else if (*ptr == '*')
+	      {
+		/* block comment */
+		base += 2;
+		ptr++;
+
+	      block_comment:
+		eol = in_comment;
+		in_comment = 1;
+		for (; *ptr; ptr++)
+		  {
+		    if (*ptr == '\n')
+		      {
+			ptr++;
+			break;
+		      }
+		    if (ptr[0] == '*' && ptr[1] == '/')
+		      {
+			in_comment = 2;
+			ptr += 2;
+			break;
+		      }
+		  }
+		kind = K_comment;
+	      }
+	    else
+	      break;
+	  }
+	  break;
+
+	case '"':
+	  /* quoted string */
+	  kind = K_string;
+	  while (*ptr)
+	    if (*ptr == '"')
+	      {
+		ptr++;
+		break;
+	      }
+	    else if (*ptr++ == '\\')
+	      ptr++;
+	  break;
+
+	case '.':
+	  if (*ptr < '0' || *ptr > '9')
+	    {
+	      kind = K_dotted;
+	      ws = not_comment;
+	      goto ident;
+	    }
+	  /* FALLTHROUGH */
+	case '0'...'9':
+	  kind = K_number;
+	  goto ident;
+	  break;
+
+	case '$':  /* local labels.  */
+	case '%':  /* register names, pseudoes etc */
+	  kind = K_ident;
+	  goto ident;
+
+	case 'a'...'z':
+	case 'A'...'Z':
+	case '_':
+	  kind = K_symbol; /* possible symbol name */
+	ident:
+	  for (; *ptr; ptr++)
+	    {
+	      if (*ptr >= 'A' && *ptr <= 'Z')
+		continue;
+	      if (*ptr >= 'a' && *ptr <= 'z')
+		continue;
+	      if (*ptr >= '0' && *ptr <= '9')
+		continue;
+	      if (*ptr == '_' || *ptr == '$')
+		continue;
+	      if (*ptr == '.' && kind != K_dotted)
+		/* Idents starting with a dot, cannot have internal dots. */
+		continue;
+	      if ((*ptr == '+' || *ptr == '-')
+		  && kind == K_number
+		  && (ptr[-1] == 'e' || ptr[-1] == 'E'
+		      || ptr[-1] == 'p' || ptr[-1] == 'P'))
+		/* exponent */
+		continue;
+	      break;
+	    }
+	  if (*ptr == ':')
+	    {
+	      ptr++;
+	      kind = K_label;
+	    }
+	  break;
+	}
+
+      if (alloc == num)
+	{
+	  alloc *= 2;
+	  toks = XRESIZEVEC (Token, toks, alloc);
+	}
+      Token *tok = toks + num;
+
+      tok->kind = kind;
+      tok->space = ws;
+      tok->end = 0;
+      tok->ptr = base;
+      tok->len = ptr - base - in_comment;
+      in_comment &= 1;
+      not_comment = kind != K_comment;
+      if (eol && num)
+	tok[-1].end = 1;
+      if (!kind)
+	break;
+    }
+
+  return toks;
+}
+
+/* Write an encoded token. */
+
+static void
+write_token (FILE *out, Token const *tok)
+{
+  if (tok->space)
+    fputc (' ', out);
+
+  switch (tok->kind)
+    {
+    case K_string:
+      {
+	const char *c = tok->ptr + 1;
+	size_t len = tok->len - 2;
+
+	fputs ("\\\"", out);
+	while (len)
+	  {
+	    const char *bs = (const char *)memchr (c, '\\', len);
+	    size_t l = bs ? bs - c : len;
+
+	    fprintf (out, "%.*s", (int)l, c);
+	    len -= l;
+	    c += l;
+	    if (bs)
+	      {
+		fputs ("\\\\", out);
+		len--, c++;
+	      }
+	  }
+	fputs ("\\\"", out);
+      }
+      break;
+
+    default:
+      /* All other tokens shouldn't have anything magic in them */
+      fprintf (out, "%.*s", tok->len, tok->ptr);
+      break;
+    }
+  if (tok->end)
+    fputs ("\\n", out);
+}
+
+static void
+write_tokens (FILE *out, Token const *toks, unsigned len, int spc)
+{
+  fputs ("\t\"", out);
+  for (; len--; toks++)
+    write_token (out, toks);
+  if (spc)
+    fputs (" ", out);
+  fputs ("\"", out);
+}
+
+static Stmt *
+alloc_stmt (unsigned vis, Token *tokens, Token *end, Token const *sym)
+{
+  static unsigned alloc = 0;
+  static Stmt *heap = 0;
+
+  if (!alloc)
+    {
+      alloc = 1000;
+      heap = XNEWVEC (Stmt, alloc);
+    }
+
+  Stmt *stmt = heap++;
+  alloc--;
+
+  tokens->space = 0;
+  stmt->next = 0;
+  stmt->vis = vis;
+  stmt->tokens = tokens;
+  stmt->len = end - tokens;
+  stmt->sym = sym ? sym - tokens : ~0;
+
+  return stmt;
+}
+
+static Stmt *
+rev_stmts (Stmt *stmt)
+{
+  Stmt *prev = 0;
+  Stmt *next;
+
+  while (stmt)
+    {
+      next = stmt->next;
+      stmt->next = prev;
+      prev = stmt;
+      stmt = next;
+    }
+
+  return prev;
+}
+
+static void
+write_stmt (FILE *out, const Stmt *stmt)
+{
+  if ((stmt->vis & V_mask) != V_comment)
+    {
+      write_tokens (out, stmt->tokens, stmt->len,
+		    (stmt->vis & V_mask) == V_pred);
+      fputs (stmt->vis & V_no_eol ? "\t" : "\n", out);
+    }
+}
+
+static void
+write_stmts (FILE *out, const Stmt *stmts)
+{
+  for (; stmts; stmts = stmts->next)
+    write_stmt (out, stmts);
+}
+
+static Token *
+parse_insn (Token *tok)
+{
+  unsigned depth = 0;
+
+  do
+    {
+      Stmt *stmt;
+      Token *sym = 0;
+      unsigned s = V_insn;
+      Token *start = tok;
+
+      switch (tok++->kind)
+	{
+	case K_comment:
+	  while (tok->kind == K_comment)
+	    tok++;
+	  stmt = alloc_comment (start, tok);
+	  append_stmt (&fns, stmt);
+	  continue;
+
+	case '{':
+	  depth++;
+	  break;
+
+	case '}':
+	  depth--;
+	  break;
+
+	case K_label:
+	  if (tok[-1].ptr[0] != '$')
+	    sym = tok - 1;
+	  tok[-1].end = 1;
+	  s = V_label;
+	  break;
+
+	case '@':
+	  tok->space = 0;
+	  if (tok->kind == '!')
+	    tok++;
+	  if (tok->kind == K_symbol)
+	    sym = tok;
+	  tok++;
+	  s = V_pred;
+	  break;
+
+	default:
+	  for (; tok->kind != ';'; tok++)
+	    {
+	      if (tok->kind == ',')
+		tok[1].space = 0;
+	      else if (tok->kind == K_symbol)
+		sym = tok;
+	    }
+	  tok++->end = 1;
+	  break;
+	}
+
+      stmt = alloc_stmt (s, start, tok, sym);
+      append_stmt (&fns, stmt);
+
+      if (!tok[-1].end && tok[0].kind == K_comment)
+	{
+	  stmt->vis |= V_no_eol;
+	  stmt = alloc_comment (tok, tok + 1);
+	  append_stmt (&fns, stmt);
+	  tok++;
+	}
+    }
+  while (depth);
+
+  return tok;
+}
+
+/* comma separated list of tokens */
+
+static Token *
+parse_list_nosemi (Token *tok)
+{
+  Token *start = tok;
+
+  do
+    if (!(++tok)->kind)
+      break;
+  while ((++tok)->kind == ',');
+
+  tok[-1].end = 1;
+  Stmt *stmt = alloc_stmt (V_dot, start, tok, 0);
+  append_stmt (&decls, stmt);
+
+  return tok;
+}
+
+#define is_keyword(T,S) \
+  (sizeof (S) == (T)->len && !memcmp ((T)->ptr + 1, (S), (T)->len - 1))
+
+static Token *
+parse_init (Token *tok)
+{
+  for (;;)
+    {
+      Token *start = tok;
+      Token const *sym = 0;
+      Stmt *stmt;
+
+      if (tok->kind == K_comment)
+	{
+	  while (tok->kind == K_comment)
+	    tok++;
+	  stmt = alloc_comment (start, tok);
+	  append_stmt (&vars, stmt);
+	  start = tok;
+	}
+
+      if (tok->kind == '{')
+	tok[1].space = 0;
+      for (; tok->kind != ',' && tok->kind != ';'; tok++)
+	if (tok->kind == K_symbol)
+	  sym = tok;
+      tok[1].space = 0;
+      int end = tok++->kind == ';';
+      stmt = alloc_stmt (V_insn, start, tok, sym);
+      append_stmt (&vars, stmt);
+      if (!tok[-1].end && tok->kind == K_comment)
+	{
+	  stmt->vis |= V_no_eol;
+	  stmt = alloc_comment (tok, tok + 1);
+	  append_stmt (&vars, stmt);
+	  tok++;
+	}
+      if (end)
+	break;
+    }
+  return tok;
+}
+
+static Token *
+parse_file (Token *tok)
+{
+  Stmt *comment = 0;
+
+  if (tok->kind == K_comment)
+    {
+      Token *start = tok;
+
+      while (tok->kind == K_comment)
+	{
+	  if (strncmp (tok->ptr, ":VAR_MAP ", 9) == 0)
+	    record_id (tok->ptr + 9, &vars_tail);
+	  if (strncmp (tok->ptr, ":FUNC_MAP ", 10) == 0)
+	    record_id (tok->ptr + 10, &funcs_tail);
+	  tok++;
+	}
+      comment = alloc_comment (start, tok);
+      comment->vis |= V_prefix_comment;
+    }
+
+  if (tok->kind == K_dotted)
+    {
+      if (is_keyword (tok, "version")
+	  || is_keyword (tok, "target")
+	  || is_keyword (tok, "address_size"))
+	{
+	  if (comment)
+	    append_stmt (&decls, comment);
+	  tok = parse_list_nosemi (tok);
+	}
+      else
+	{
+	  unsigned vis = 0;
+	  const Token *def = 0;
+	  unsigned is_decl = 0;
+	  Token *start;
+
+	  for (start = tok;
+	       tok->kind && tok->kind != '=' && tok->kind != K_comment
+		 && tok->kind != '{' && tok->kind != ';'; tok++)
+	    {
+	      if (is_keyword (tok, "global")
+		  || is_keyword (tok, "const"))
+		vis |= V_var;
+	      else if (is_keyword (tok, "func")
+		       || is_keyword (tok, "entry"))
+		vis |= V_func;
+	      else if (is_keyword (tok, "visible"))
+		vis |= V_global;
+	      else if (is_keyword (tok, "extern"))
+		is_decl = 1;
+	      else if (is_keyword (tok, "weak"))
+		vis |= V_weak;
+	      if (tok->kind == '(')
+		{
+		  tok[1].space = 0;
+		  tok[0].space = 1;
+		}
+	      else if (tok->kind == ')' && tok[1].kind != ';')
+		tok[1].space = 1;
+
+	      if (tok->kind == K_symbol)
+		def = tok;
+	    }
+
+	  if (!tok->kind)
+	    {
+	      /* end of file */
+	      if (comment)
+		append_stmt (&fns, comment);
+	    }
+	  else if (tok->kind == '{'
+		   || tok->kind == K_comment)
+	    {
+	      /* function defn */
+	      Stmt *stmt = alloc_stmt (vis, start, tok, def);
+	      if (comment)
+		{
+		  append_stmt (&fns, comment);
+		  stmt->vis |= V_prefix_comment;
+		}
+	      append_stmt (&fns, stmt);
+	      tok = parse_insn (tok);
+	    }
+	  else
+	    {
+	      int assign = tok->kind == '=';
+
+	      tok++->end = 1;
+	      if ((vis & V_mask) == V_var && !is_decl)
+		{
+		  /* variable */
+		  Stmt *stmt = alloc_stmt (vis, start, tok, def);
+		  if (comment)
+		    {
+		      append_stmt (&vars, comment);
+		      stmt->vis |= V_prefix_comment;
+		    }
+		  append_stmt (&vars, stmt);
+		  if (assign)
+		    tok = parse_init (tok);
+		}
+	      else
+		{
+		  /* declaration */
+		  Stmt *stmt = alloc_stmt (vis, start, tok, 0);
+		  if (comment)
+		    {
+		      append_stmt (&decls, comment);
+		      stmt->vis |= V_prefix_comment;
+		    }
+		  append_stmt (&decls, stmt);
+		}
+	    }
+	}
+    }
+  else
+    {
+      /* Something strange.  Ignore it.  */
+      if (comment)
+	append_stmt (&fns, comment);
+
+      while (tok->kind && !tok->end)
+	tok++;
+    }
+  return tok;
+}
+
+static void
+process (FILE *in, FILE *out)
+{
+  const char *input = read_file (in);
+  Token *tok = tokenize (input);
+
+  do
+    tok = parse_file (tok);
+  while (tok->kind);
+
+  fprintf (out, "static const char ptx_code[] = \n");
+  write_stmts (out, rev_stmts (decls));
+  write_stmts (out, rev_stmts (vars));
+  write_stmts (out, rev_stmts (fns));
+  fprintf (out, ";\n\n");
+  fprintf (out, "static const char *var_mappings[] = {\n");
+  for (id_map *id = var_ids; id; id = id->next)
+    fprintf (out, "\t\"%s\"%s\n", id->ptx_name, id->next ? "," : "");
+  fprintf (out, "};\n\n");
+  fprintf (out, "static const char *func_mappings[] = {\n");
+  for (id_map *id = func_ids; id; id = id->next)
+    fprintf (out, "\t\"%s\"%s\n", id->ptx_name, id->next ? "," : "");
+  fprintf (out, "};\n\n");
+
+  fprintf (out, "static const void *target_data[] = {\n");
+  fprintf (out, "  ptx_code, var_mappings, func_mappings\n");
+  fprintf (out, "};\n\n");
+
+  fprintf (out, "extern void GOMP_offload_register (const void *, int, void *);\n");
+
+  fprintf (out, "extern void *__OPENMP_TARGET__[];\n\n");
+  fprintf (out, "#define PTX_ID 1\n");
+  fprintf (out, "static __attribute__((constructor)) void init (void)\n{\n");
+  fprintf (out, "  GOMP_offload_register (__OPENMP_TARGET__, PTX_ID,\n");
+  fprintf (out, "                         &target_data);\n");
+  fprintf (out, "};\n");
+}
+
+static void
+compile_native (const char *infile, const char *outfile, const char *compiler)
+{
+  const char *collect_gcc_options = getenv ("COLLECT_GCC_OPTIONS");
+  if (!collect_gcc_options)
+    fatal_error ("environment variable COLLECT_GCC_OPTIONS must be set");
+
+  struct obstack argv_obstack;
+  obstack_init (&argv_obstack);
+  obstack_ptr_grow (&argv_obstack, compiler);
+  obstack_ptr_grow (&argv_obstack, infile);
+  obstack_ptr_grow (&argv_obstack, "-c");
+  obstack_ptr_grow (&argv_obstack, "-o");
+  obstack_ptr_grow (&argv_obstack, outfile);
+  obstack_ptr_grow (&argv_obstack, NULL);
+
+  const char **new_argv = XOBFINISH (&argv_obstack, const char **);
+  fork_execute (new_argv[0], CONST_CAST (char **, new_argv), true);
+  obstack_free (&argv_obstack, NULL);
+}
+
+int
+main (int argc, char **argv)
+{
+  FILE *in = stdin;
+  FILE *out = stdout;
+  const char *outname = 0;
+
+  char *collect_gcc = getenv ("COLLECT_GCC");
+  if (collect_gcc == NULL)
+    fatal_error ("COLLECT_GCC must be set.");
+  const char *gcc_path = dirname (ASTRDUP (collect_gcc));
+  const char *gcc_exec = basename (ASTRDUP (collect_gcc));
+
+  size_t len = (strlen (gcc_path) + 1
+		+ strlen (GCC_INSTALL_NAME)
+		+ 1);
+  char *driver = XALLOCAVEC (char, len);
+
+  if (strcmp (gcc_exec, collect_gcc) == 0)
+    /* collect_gcc has no path, so it was found in PATH.  Make sure we also
+       find accel-gcc in PATH.  */
+    gcc_path = NULL;
+
+  int driver_used = 0;
+  if (gcc_path != NULL)
+    driver_used = sprintf (driver, "%s/", gcc_path);
+  sprintf (driver + driver_used, "%s", GCC_INSTALL_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);
+
+  struct obstack argv_obstack;
+  obstack_init (&argv_obstack);
+  obstack_ptr_grow (&argv_obstack, driver);
+  obstack_ptr_grow (&argv_obstack, "-xlto");
+  obstack_ptr_grow (&argv_obstack, "-m64");
+  obstack_ptr_grow (&argv_obstack, "-S");
+
+  for (int ix = 1; ix != argc; ix++)
+    {
+      if (!strcmp (argv[ix], "-o") && ix + 1 != argc)
+	outname = argv[++ix];
+      else
+	obstack_ptr_grow (&argv_obstack, argv[ix]);
+    }
+
+  ptx_name = make_temp_file (".mkoffload");
+  obstack_ptr_grow (&argv_obstack, "-o");
+  obstack_ptr_grow (&argv_obstack, ptx_name);
+  obstack_ptr_grow (&argv_obstack, NULL);
+  const char **new_argv = XOBFINISH (&argv_obstack, const char **);
+
+  char *execpath = getenv ("GCC_EXEC_PREFIX");
+  char *cpath = getenv ("COMPILER_PATH");
+  char *lpath = getenv ("LIBRARY_PATH");
+  unsetenv ("GCC_EXEC_PREFIX");
+  unsetenv ("COMPILER_PATH");
+  unsetenv ("LIBRARY_PATH");
+
+  fork_execute (new_argv[0], CONST_CAST (char **, new_argv), true);
+  obstack_free (&argv_obstack, NULL);
+
+  xputenv (concat ("GCC_EXEC_PREFIX=", execpath, NULL));
+  xputenv (concat ("COMPILER_PATH=", cpath, NULL));
+  xputenv (concat ("LIBRARY_PATH=", lpath, NULL));
+
+  in = fopen (ptx_name, "r");
+  if (!in)
+    fatal_error ("cannot open intermediate ptx file");
+
+  ptx_cfile_name = make_temp_file (".c");
+
+  out = fopen (ptx_cfile_name, "w");
+  if (!out)
+    fatal_error ("cannot open '%s'", ptx_cfile_name);
+
+  process (in, out);
+  fclose (out);
+
+  compile_native (ptx_cfile_name, outname, collect_gcc);
+
+  utils_cleanup (false);
+
+  return 0;
+}
Index: git/gcc/config.gcc
===================================================================
--- git.orig/gcc/config.gcc
+++ git/gcc/config.gcc
@@ -2155,6 +2155,9 @@  nvptx-*)
 	tm_file="${tm_file} newlib-stdint.h"
 	tmake_file="nvptx/t-nvptx"
 	extra_programs="collect-ld\$(exeext) as\$(exeext) ar\$(exeext) ranlib\$(exeext)"
+	if test x$enable_as_accelerator = xyes; then
+		extra_programs="${extra_programs} mkoffload\$(exeext)"
+	fi
 	;;
 pdp11-*-*)
 	tm_file="${tm_file} newlib-stdint.h"
Index: git/gcc/config/nvptx/t-nvptx
===================================================================
--- git.orig/gcc/config/nvptx/t-nvptx
+++ git/gcc/config/nvptx/t-nvptx
@@ -1,5 +1,15 @@ 
 #
 
+CFLAGS-mkoffload.o += $(DRIVER_DEFINES) \
+	-DGCC_INSTALL_NAME=\"$(GCC_INSTALL_NAME)\"
+mkoffload.o: $(srcdir)/config/nvptx/mkoffload.c
+	$(COMPILE) $<
+	$(POSTCOMPILE)
+
+mkoffload$(exeext): mkoffload.o collect-utils.o libcommon-target.a $(LIBIBERTY) $(LIBDEPS)
+	+$(LINKER) $(ALL_LINKERFLAGS) $(LDFLAGS) -o $@ \
+	  mkoffload.o collect-utils.o libcommon-target.a $(LIBIBERTY) $(LIBS)
+
 nvptx-ld.o: $(srcdir)/config/nvptx/nvptx-ld.c
 	$(COMPILE) $<
 	$(POSTCOMPILE)
@@ -23,5 +33,3 @@  ar$(exeext):
 ranlib$(exeext):
 	echo -e "#! /bin/sh\n$(RANLIB) \"$$""@\"" >$@
 	chmod a+x $@
-
-
Index: git/gcc/config/nvptx/nvptx.c
===================================================================
--- git.orig/gcc/config/nvptx/nvptx.c
+++ git/gcc/config/nvptx/nvptx.c
@@ -1990,6 +1990,16 @@  nvptx_vector_alignment (const_tree type)
   return MIN (align, BIGGEST_ALIGNMENT);
 }
 
+/* Record a symbol for mkoffload to enter into the mapping table.  */
+
+static void
+nvptx_record_offload_symbol (tree decl)
+{
+  fprintf (asm_out_file, "//:%s_MAP %s\n",
+	   TREE_CODE (decl) == VAR_DECL ? "VAR" : "FUNC",
+	   IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
+}
+
 /* Implement TARGET_ASM_FILE_START.  Write the kinds of things ptxas expects
    at the start of a file.  */
 
@@ -2101,6 +2111,9 @@  nvptx_file_end (void)
 #undef TARGET_NO_REGISTER_ALLOCATION
 #define TARGET_NO_REGISTER_ALLOCATION true
 
+#undef TARGET_RECORD_OFFLOAD_SYMBOL
+#define TARGET_RECORD_OFFLOAD_SYMBOL nvptx_record_offload_symbol
+
 #undef TARGET_VECTOR_ALIGNMENT
 #define TARGET_VECTOR_ALIGNMENT nvptx_vector_alignment