1 /* Usage example for libgccjit.so's C++ API
2 Copyright (C) 2014-2016 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 /*
29 Simple sum-of-squares, to test conditionals and looping
30
31 int loop_test (int n)
32 {
33 int i;
34 int sum = 0;
35 for (i = 0; i < n ; i ++)
36 {
37 sum += i * i;
38 }
39 return sum;
40 */
41 gccjit::type the_type = ctxt.get_int_type <int> ();
42 gccjit::type return_type = the_type;
43
44 gccjit::param n = ctxt.new_param (the_type, "n");
45 std::vector<gccjit::param> params;
46 params.push_back (n);
47 gccjit::function func =
48 ctxt.new_function (GCC_JIT_FUNCTION_EXPORTED,
49 return_type,
50 "loop_test",
51 params, 0);
52
53 /* Build locals: */
54 gccjit::lvalue i = func.new_local (the_type, "i");
55 gccjit::lvalue sum = func.new_local (the_type, "sum");
56
57 gccjit::block b_initial = func.new_block ("initial");
58 gccjit::block b_loop_cond = func.new_block ("loop_cond");
59 gccjit::block b_loop_body = func.new_block ("loop_body");
60 gccjit::block b_after_loop = func.new_block ("after_loop");
61
62 /* sum = 0; */
63 b_initial.add_assignment (sum, ctxt.zero (the_type));
64
65 /* i = 0; */
66 b_initial.add_assignment (i, ctxt.zero (the_type));
67
68 b_initial.end_with_jump (b_loop_cond);
69
70 /* if (i >= n) */
71 b_loop_cond.end_with_conditional (
72 i >= n,
73 b_after_loop,
74 b_loop_body);
75
76 /* sum += i * i */
77 b_loop_body.add_assignment_op (sum,
78 GCC_JIT_BINARY_OP_PLUS,
79 i * i);
80
81 /* i++ */
82 b_loop_body.add_assignment_op (i,
83 GCC_JIT_BINARY_OP_PLUS,
84 ctxt.one (the_type));
85
86 b_loop_body.end_with_jump (b_loop_cond);
87
88 /* return sum */
89 b_after_loop.end_with_return (sum);
90 }
91
92 int
main(int argc,char ** argv)93 main (int argc, char **argv)
94 {
95 gccjit::context ctxt;
96 gcc_jit_result *result = NULL;
97
98 /* Get a "context" object for working with the library. */
99 ctxt = gccjit::context::acquire ();
100
101 /* Set some options on the context.
102 Turn this on to see the code being generated, in assembler form. */
103 ctxt.set_bool_option (GCC_JIT_BOOL_OPTION_DUMP_GENERATED_CODE,
104 0);
105
106 /* Populate the context. */
107 create_code (ctxt);
108
109 /* Compile the code. */
110 result = ctxt.compile ();
111
112 ctxt.release ();
113
114 if (!result)
115 {
116 fprintf (stderr, "NULL result");
117 return 1;
118 }
119
120 /* Extract the generated code from "result". */
121 typedef int (*loop_test_fn_type) (int);
122 loop_test_fn_type loop_test =
123 (loop_test_fn_type)gcc_jit_result_get_code (result, "loop_test");
124 if (!loop_test)
125 {
126 fprintf (stderr, "NULL loop_test");
127 gcc_jit_result_release (result);
128 return 1;
129 }
130
131 /* Run the generated code. */
132 int val = loop_test (10);
133 printf("loop_test returned: %d\n", val);
134
135 gcc_jit_result_release (result);
136 return 0;
137 }
138