Add gemma.cpp bindings / llm-chain-gemma.

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "crates/llm-chain-llama/sys/llama.cpp"]
 	path = crates/llm-chain-llama-sys/llama.cpp
 	url = https://github.com/ggerganov/llama.cpp.git
+[submodule "crates/llm-chain-gemma-sys/gemma.cpp"]
+	path = crates/llm-chain-gemma-sys/gemma.cpp
+	url = https://github.com/google/gemma.cpp.git

crates/llm-chain-gemma-sys/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "llm-chain-gemma-sys"
+description = "A library with bindings for gemma.cpp"
+version = "0.1.0"
+edition = "2021"
+license = "MIT"
+keywords = ["llm", "langchain", "gemma", "chain"]
+categories = ["science"]
+authors = [
+    "Jun Mukai <[email protected]>",
+]
+repository = "https://github.com/sobelio/llm-chain/"
+readme = "README.md"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+[build-dependencies]
+cc = "1.0.87"

crates/llm-chain-gemma-sys/build.rs

@@ -0,0 +1,123 @@
+#![allow(clippy::uninlined_format_args)]
+
+extern crate cc;
+
+use std::env;
+
+fn main() {
+    let target = env::var("TARGET").unwrap();
+    // Link C++ standard library
+    if let Some(cpp_stdlib) = get_cpp_link_stdlib(&target) {
+        println!("cargo:rustc-link-lib=dylib={}", cpp_stdlib);
+        println!("cargo:rustc-link-arg=-l{}", cpp_stdlib);
+    }
+    // Link macOS Accelerate framework for matrix calculations
+    if target.contains("apple") {
+        println!("cargo:rustc-link-lib=framework=Accelerate");
+    }
+    println!("cargo:rustc-link-search={}", env::var("OUT_DIR").unwrap());
+    println!("cargo:rustc-link-lib=static=gemma");
+    println!("cargo:rustc-link-lib=static=hwy");
+    println!("cargo:rustc-link-lib=static=hwy_contrib");
+    println!("cargo:rustc-link-lib=static=sentencepiece");
+    println!("cargo:rustc-link-lib=static=bindings");
+    println!("cargo:rerun-if-changed=wrapper.h");
+
+    // stop if we're on docs.rs
+    if env::var("DOCS_RS").is_ok() {
+        return;
+    }
+
+    // Run cmake to generate build files.
+    env::set_current_dir("gemma.cpp").expect("Unable to change directory to gemma.cpp");
+    env::set_current_dir("build").expect("Unable to change directory to gemma.cpp build");
+
+    env::set_var("CXXFLAGS", "-fPIC");
+    env::set_var("CFLAGS", "-fPIC");
+
+    let mut code = std::process::Command::new("cmake");
+    let code = code
+        .arg("..")
+        .arg("-DCMAKE_BUILD_TYPE=Release")
+        .arg("-DBUILD_SHARED_LIBS=OFF")
+        .arg("-DWEIGHT_TYPE=hwy::bfloat16_t")
+        .arg("-DSPM_ENABLE_SHARED=OFF");
+    let code = code.status().expect("Failed to generate build script");
+    if code.code() != Some(0) {
+        panic!("Failed to generate build script");
+    }
+
+    // Build binary.
+    #[allow(clippy::suspicious_command_arg_space)]
+    let code = std::process::Command::new("cmake")
+        .arg("--build")
+        .arg(".")
+        .arg("--config Release")
+        .arg("--")
+        .arg("libgemma")
+        .status()
+        .expect("Failed to build lib");
+    if code.code() != Some(0) {
+        panic!("Failed to build lib");
+    }
+
+    // move libllama.a to where Cargo expects it (OUT_DIR)
+    #[cfg(target_os = "windows")]
+    {
+        // I haven't tested windows, so it's not supported yet.
+    }
+
+    #[cfg(not(target_os = "windows"))]
+    {
+        std::fs::copy(
+            "libgemma.a",
+            format!("{}/libgemma.a", env::var("OUT_DIR").unwrap()),
+        )
+        .expect("Failed to copy lib");
+
+        std::fs::copy(
+            "_deps/highway-build/libhwy.a",
+            format!("{}/libhwy.a", env::var("OUT_DIR").unwrap()),
+        )
+        .expect("Failed to copy libwhy.a");
+
+        std::fs::copy(
+            "_deps/highway-build/libhwy_contrib.a",
+            format!("{}/libhwy_contrib.a", env::var("OUT_DIR").unwrap()),
+        )
+        .expect("Failed to copy libwhy_contrib.a");
+
+        std::fs::copy(
+            "_deps/sentencepiece-build/src/libsentencepiece.a",
+            format!("{}/libsentencepiece.a", env::var("OUT_DIR").unwrap()),
+        )
+        .expect("Failed to copy libsentencepiece.a");
+    }
+
+    // Finally, build bindings.cc to allow access for gemma.cpp.
+    // So far, bindgen does not correctly generate buildable rust file,
+    // so I manually wrote bindings.rs for hand-written src/bindings.cc file.
+    env::set_current_dir("..").expect("Unlable to change directory back to gemma.cpp");
+    env::set_current_dir("..").expect("Unlable to change directory back to crate top");
+
+    cc::Build::new()
+        .cpp(true)
+        .file("src/bindings.cc")
+        .include("./gemma.cpp")
+        .include("./gemma.cpp/build/_deps/highway-src")
+        .include("./gemma.cpp/build/_deps/sentencepiece-src")
+        .compile("bindings");
+}
+
+// From https://github.com/alexcrichton/cc-rs/blob/fba7feded71ee4f63cfe885673ead6d7b4f2f454/src/lib.rs#L2462
+fn get_cpp_link_stdlib(target: &str) -> Option<&'static str> {
+    if target.contains("msvc") {
+        None
+    } else if target.contains("apple") || target.contains("freebsd") || target.contains("openbsd") {
+        Some("c++")
+    } else if target.contains("android") {
+        Some("c++_shared")
+    } else {
+        Some("stdc++")
+    }
+}