tflite 0.4.0

Rust bindings for TensorFlow Lite
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233

extern crate bindgen;
extern crate cpp_build;
extern crate curl;
extern crate failure;
extern crate flate2;
extern crate hex;
extern crate reqwest;
extern crate sha2;
extern crate tar;

use std::env;
use std::fs;
use std::path::{Path, PathBuf};
use std::process::Command;

use failure::Fallible;

const TFLITE_VERSION: &'static str = "1.13.2";

fn is_valid_tf_src<P: AsRef<Path>>(filepath: P) -> bool {
    use sha2::{Digest, Sha256};

    let mut sha256 = Sha256::new();
    sha256.input(&fs::read(filepath).unwrap());
    ::hex::encode(sha256.result())
        == "abe3bf0c47845a628b7df4c57646f41a10ee70f914f1b018a5c761be75e1f1a9"
}

fn download<P: reqwest::IntoUrl, P2: AsRef<Path>>(source_url: P, target_file: P2) -> Fallible<()> {
    let mut resp = reqwest::get(source_url)?;
    let f = fs::File::create(&target_file)?;
    let mut writer = ::std::io::BufWriter::new(f);
    resp.copy_to(&mut writer)?;
    Ok(())
}

fn extract<P: AsRef<Path>, P2: AsRef<Path>>(archive_path: P, extract_to: P2) {
    use flate2::read::GzDecoder;
    use tar::Archive;

    let file = fs::File::open(archive_path).unwrap();
    let unzipped = GzDecoder::new(file);
    let mut a = Archive::new(unzipped);
    a.unpack(extract_to).unwrap();
}

fn prepare_tensorflow_source() -> PathBuf {
    let tf_src_dir = PathBuf::from(env::var("OUT_DIR").unwrap()).join("tensorflow");
    fs::create_dir(&tf_src_dir).unwrap_or_default();

    let tf_src_name = tf_src_dir.join(format!("v{}.tar.gz", TFLITE_VERSION));
    if !tf_src_name.exists() || !is_valid_tf_src(&tf_src_name) {
        let tf_src_url = format!(
            "https://codeload.github.com/tensorflow/tensorflow/tar.gz/v{}",
            TFLITE_VERSION
        );

        download(&tf_src_url, &tf_src_name).unwrap();

        assert!(
            is_valid_tf_src(&tf_src_name),
            "{} is not valid",
            tf_src_name.to_str().unwrap()
        );
    }

    let tf_src_dir_inner = tf_src_dir.join(format!("tensorflow-{}", TFLITE_VERSION));
    if !tf_src_dir_inner.exists() {
        extract(&tf_src_name, &tf_src_dir);

        Command::new("tensorflow/lite/tools/make/download_dependencies.sh")
            .current_dir(&tf_src_dir_inner)
            .status()
            .expect("failed to download tflite dependencies.");

        // To compile C files with -fPIC
        if env::var("CARGO_CFG_TARGET_OS").unwrap() == "linux" {
            fs::copy(
                "data/linux_makefile.inc",
                tf_src_dir_inner.join("tensorflow/lite/tools/make/targets/linux_makefile.inc"),
            )
            .expect("Unable to copy linux makefile");
        }
        // To allow for cross-compiling to aarch64
        if env::var("CARGO_CFG_TARGET_ARCH").unwrap() == "aarch64" {
            fs::copy(
                "data/aarch64_makefile.inc",
                tf_src_dir_inner.join("tensorflow/lite/tools/make/targets/aarch64_makefile.inc"),
            )
            .expect("Unable to copy aarch64 makefile");
        }

        #[cfg(feature = "debug_tflite")]
        {
            Command::new("sed")
                .arg("-i")
                .arg("54s/.*/CXXFLAGS := -O0 -g -fno-inline/")
                .arg("tensorflow/lite/tools/make/Makefile")
                .current_dir(&tf_src_dir_inner)
                .status()
                .expect("failed to edit Makefile.");

            Command::new("sed")
                .arg("-i")
                .arg("57s/.*/CFLAGS := -O0 -g -fno-inline/")
                .arg("tensorflow/lite/tools/make/Makefile")
                .current_dir(&tf_src_dir_inner)
                .status()
                .expect("failed to edit Makefile.");
        }
    }
    tf_src_dir_inner
}

fn prepare_tensorflow_library<P: AsRef<Path>>(tflite: P) {
    let tf_lib_name = PathBuf::from(env::var("OUT_DIR").unwrap()).join("libtensorflow-lite.a");
    let os = env::var("CARGO_CFG_TARGET_OS").expect("Unable to get TARGET_OS");
    let arch = env::var("CARGO_CFG_TARGET_ARCH").expect("Unable to get TARGET_ARCH");
    if !tf_lib_name.exists() {
        Command::new("make")
            .arg("-j")
            // allow parallelism to be overridden
            .arg(env::var("TFLITE_RS_MAKE_PARALLELISM").unwrap_or("3".to_owned()))
            .arg("-f")
            .arg("tensorflow/lite/tools/make/Makefile")
            // Use cargo's cross-compilation information while building tensorflow
            .arg(format!("TARGET={}", os))
            .arg(format!("TARGET_ARCH={}", arch))
            .current_dir(&tflite)
            .status()
            .expect("failed to build tensorflow");

        fs::copy(
            tflite.as_ref().join(format!(
                "tensorflow/lite/tools/make/gen/{OS}_{ARCH}/lib/libtensorflow-lite.a",
                OS = os,
                ARCH = arch,
            )),
            &tf_lib_name,
        )
        .expect("Unable to copy libtensorflow-lite.a to OUT_DIR");
    }
}

// This generates "tflite_types.rs" containing structs and enums which are inter-operable with Glow.
fn import_tflite_types<P: AsRef<Path>>(tflite: P) {
    use bindgen::*;

    let bindings = Builder::default()
        .whitelist_recursively(false)
        .prepend_enum_name(false)
        .impl_debug(true)
        .with_codegen_config(CodegenConfig::TYPES)
        .layout_tests(false)
        .enable_cxx_namespaces()
        .derive_default(true)
        .whitelist_type("tflite::FlatBufferModel")
        .opaque_type("tflite::FlatBufferModel")
        .whitelist_type("tflite::InterpreterBuilder")
        .opaque_type("tflite::InterpreterBuilder")
        .whitelist_type("tflite::Interpreter")
        .opaque_type("tflite::Interpreter")
        .whitelist_type("tflite::ops::builtin::BuiltinOpResolver")
        .opaque_type("tflite::ops::builtin::BuiltinOpResolver")
        .whitelist_type("tflite::OpResolver")
        .opaque_type("tflite::OpResolver")
        .whitelist_type("TfLiteTensor")
        .whitelist_type("TfLiteType")
        .whitelist_type("TfLitePtrUnion")
        .whitelist_type("TfLiteIntArray")
        .whitelist_type("TfLiteQuantizationParams")
        .whitelist_type("TfLiteAllocationType")
        .whitelist_type("TfLiteDelegate")
        .opaque_type("TfLiteDelegate")
        .whitelist_type("TfLiteBufferHandle")
        .whitelist_type("TfLiteComplex64")
        .whitelist_type("TfLiteStatus")
        .whitelist_type("TfLiteQuantizationParams")
        .blacklist_type("std")
        .blacklist_type("tflite::Interpreter_TfLiteDelegatePtr")
        .blacklist_type("tflite::Interpreter_State")
        .default_enum_style(EnumVariation::Rust {
            non_exhaustive: false,
        })
        .header("csrc/tflite_wrapper.hpp")
        .clang_arg(format!("-I{}", tflite.as_ref().to_str().unwrap()))
        .clang_arg(format!(
            "-I{}/tensorflow/lite/tools/make/downloads/flatbuffers/include",
            tflite.as_ref().to_str().unwrap()
        ))
        .clang_arg("-DGEMMLOWP_ALLOW_SLOW_SCALAR_FALLBACK")
        .clang_arg("-x")
        .clang_arg("c++")
        .clang_arg("-std=c++11")
        // required to get cross compilation for aarch64 to work because of an issue in flatbuffers
        .clang_arg("-fms-extensions");

    let bindings = bindings.generate().expect("Unable to generate bindings");

    // Write the bindings to the $OUT_DIR/tflite_types.rs file.
    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("tflite_types.rs");
    bindings
        .write_to_file(out_path)
        .expect("Couldn't write bindings!");
}

fn build_inline_cpp<P: AsRef<Path>>(tflite: P) {
    println!("cargo:rustc-link-lib=static=tensorflow-lite");
    println!("cargo:rustc-link-lib=dylib=pthread");
    println!("cargo:rustc-link-lib=dylib=dl");

    cpp_build::Config::new()
        .include(tflite.as_ref())
        .include(
            tflite
                .as_ref()
                .join("tensorflow/lite/tools/make/downloads/flatbuffers/include"),
        )
        .flag("-fPIC")
        .flag("-std=c++11")
        .flag("-Wno-sign-compare")
        .define("GEMMLOWP_ALLOW_SLOW_SCALAR_FALLBACK", None)
        .debug(true)
        .opt_level(2)
        .build("src/lib.rs");
}

fn main() {
    let tflite_src_dir = prepare_tensorflow_source();
    prepare_tensorflow_library(&tflite_src_dir);
    import_tflite_types(&tflite_src_dir);
    build_inline_cpp(&tflite_src_dir);
}