1 /* Usage example for libgccjit.so's C++ API
2 Copyright (C) 2014-2020 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10
11 GCC is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along 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
25 void
create_code(gccjit::context ctxt)26 create_code (gccjit::context ctxt)
27 {
28 /* Let's try to inject the equivalent of this C code:
29
30 int square (int i)
31 {
32 return i * i;
33 }
34 */
35 gccjit::type int_type = ctxt.get_type (GCC_JIT_TYPE_INT);
36 gccjit::param param_i = ctxt.new_param (int_type, "i");
37 std::vector<gccjit::param> params;
38 params.push_back (param_i);
39 gccjit::function func = ctxt.new_function (GCC_JIT_FUNCTION_EXPORTED,
40 int_type,
41 "square",
42 params, 0);
43
44 gccjit::block block = func.new_block ();
45
46 gccjit::rvalue expr =
47 ctxt.new_binary_op (GCC_JIT_BINARY_OP_MULT, int_type,
48 param_i, param_i);
49
50 block.end_with_return (expr);
51 }
52
53 int
main(int argc,char ** argv)54 main (int argc, char **argv)
55 {
56 /* Get a "context" object for working with the library. */
57 gccjit::context ctxt = gccjit::context::acquire ();
58
59 /* Set some options on the context.
60 Turn this on to see the code being generated, in assembler form. */
61 ctxt.set_bool_option (
62 GCC_JIT_BOOL_OPTION_DUMP_GENERATED_CODE,
63 0);
64
65 /* Populate the context. */
66 create_code (ctxt);
67
68 /* Compile the code. */
69 gcc_jit_result *result = ctxt.compile ();
70
71 /* We're done with the context; we can release it: */
72 ctxt.release ();
73
74 if (!result)
75 {
76 fprintf (stderr, "NULL result");
77 return 1;
78 }
79
80 /* Extract the generated code from "result". */
81 void *fn_ptr = gcc_jit_result_get_code (result, "square");
82 if (!fn_ptr)
83 {
84 fprintf (stderr, "NULL fn_ptr");
85 gcc_jit_result_release (result);
86 return 1;
87 }
88
89 typedef int (*fn_type) (int);
90 fn_type square = (fn_type)fn_ptr;
91 printf ("result: %d\n", square (5));
92
93 gcc_jit_result_release (result);
94 return 0;
95 }
96