1/* Usage example for libgccjit.so
2   Copyright (C) 2014-2015 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it
7under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 3, or (at your option)
9any later version.
10
11GCC is distributed in the hope that it will be useful, but
12WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20#include <libgccjit.h>
21
22#include <stdlib.h>
23#include <stdio.h>
24
25void
26create_code (gcc_jit_context *ctxt)
27{
28  /* Let's try to inject the equivalent of:
29
30      int square (int i)
31      {
32        return i * i;
33      }
34  */
35  gcc_jit_type *int_type =
36    gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_INT);
37  gcc_jit_param *param_i =
38    gcc_jit_context_new_param (ctxt, NULL, int_type, "i");
39  gcc_jit_function *func =
40    gcc_jit_context_new_function (ctxt, NULL,
41                                  GCC_JIT_FUNCTION_EXPORTED,
42                                  int_type,
43                                  "square",
44                                  1, &param_i,
45                                  0);
46
47  gcc_jit_block *block = gcc_jit_function_new_block (func, NULL);
48
49  gcc_jit_rvalue *expr =
50    gcc_jit_context_new_binary_op (
51      ctxt, NULL,
52      GCC_JIT_BINARY_OP_MULT, int_type,
53      gcc_jit_param_as_rvalue (param_i),
54      gcc_jit_param_as_rvalue (param_i));
55
56   gcc_jit_block_end_with_return (block, NULL, expr);
57}
58
59int
60main (int argc, char **argv)
61{
62  gcc_jit_context *ctxt = NULL;
63  gcc_jit_result *result = NULL;
64
65  /* Get a "context" object for working with the library.  */
66  ctxt = gcc_jit_context_acquire ();
67  if (!ctxt)
68    {
69      fprintf (stderr, "NULL ctxt");
70      goto error;
71    }
72
73  /* Set some options on the context.
74     Let's see the code being generated, in assembler form.  */
75  gcc_jit_context_set_bool_option (
76    ctxt,
77    GCC_JIT_BOOL_OPTION_DUMP_GENERATED_CODE,
78    0);
79
80  /* Populate the context.  */
81  create_code (ctxt);
82
83  /* Compile the code.  */
84  result = gcc_jit_context_compile (ctxt);
85  if (!result)
86    {
87      fprintf (stderr, "NULL result");
88      goto error;
89    }
90
91  /* We're done with the context; we can release it: */
92  gcc_jit_context_release (ctxt);
93  ctxt = NULL;
94
95  /* Extract the generated code from "result".  */
96  void *fn_ptr = gcc_jit_result_get_code (result, "square");
97  if (!fn_ptr)
98     {
99       fprintf (stderr, "NULL fn_ptr");
100       goto error;
101     }
102
103  typedef int (*fn_type) (int);
104  fn_type square = (fn_type)fn_ptr;
105  printf ("result: %d\n", square (5));
106
107 error:
108  if (ctxt)
109    gcc_jit_context_release (ctxt);
110  if (result)
111    gcc_jit_result_release (result);
112  return 0;
113}
114