1 /* Usage example for libgccjit.so
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(gcc_jit_context * ctxt)26 create_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, ¶m_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
59 int
main(int argc,char ** argv)60 main (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