ex_maxsim_cpu

use std::env;
use std::path::PathBuf;

fn main() {
    // Tell cargo to rerun this script if build.rs changes
    println!("cargo:rerun-if-changed=build.rs");

    // Platform-specific linking
    #[cfg(all(target_os = "linux", not(feature = "use-libxsmm")))]
    {
        // On Linux without libxsmm, we need to explicitly link system OpenBLAS
        println!("cargo:rustc-link-lib=openblas");
    }

    // Only link libxsmm if the feature is enabled
    if cfg!(feature = "use-libxsmm") {
        // Look for LIBXSMM_DIR or LIBXSMM_LIB_DIR
        let libxsmm_dir = env::var("LIBXSMM_DIR")
            .or_else(|_| {
                env::var("LIBXSMM_LIB_DIR").map(|lib_dir| {
                    // If we have LIBXSMM_LIB_DIR, assume parent dir is LIBXSMM_DIR
                    PathBuf::from(&lib_dir)
                        .parent()
                        .unwrap()
                        .to_string_lossy()
                        .to_string()
                })
            })
            .expect("LIBXSMM_DIR or LIBXSMM_LIB_DIR must be set when using use-libxsmm feature");

        let libxsmm_path = PathBuf::from(libxsmm_dir);

        // Add library search path
        println!(
            "cargo:rustc-link-search=native={}/lib",
            libxsmm_path.display()
        );

        // Force static linking of libxsmm
        println!("cargo:rustc-link-lib=static=xsmm");
        println!("cargo:rustc-link-lib=static=xsmmext");

        // Link against BLAS (OpenBLAS or system BLAS)
        println!("cargo:rustc-link-lib=openblas");

        // Link with standard libraries that libxsmm needs
        println!("cargo:rustc-link-lib=dl");
        println!("cargo:rustc-link-lib=m");
        println!("cargo:rustc-link-lib=pthread");
        println!("cargo:rustc-link-lib=stdc++");
        println!("cargo:rustc-link-lib=gomp"); // OpenMP support

        // Tell cargo to rerun if libxsmm libs change
        println!("cargo:rerun-if-changed={}/lib", libxsmm_path.display());
    }
}