| // Copyright 2015 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| use syntax::{ast, attr}; |
| use llvm::LLVMRustHasFeature; |
| use rustc::session::Session; |
| use rustc_trans::back::write::create_target_machine; |
| use syntax::parse::token::InternedString; |
| use syntax::parse::token::intern_and_get_ident as intern; |
| use libc::c_char; |
| |
| // WARNING: the features must be known to LLVM or the feature |
| // detection code will walk past the end of the feature array, |
| // leading to crashes. |
| |
| const ARM_WHITELIST: &'static [&'static str] = &[ |
| "neon\0", |
| "vfp2\0", |
| "vfp3\0", |
| "vfp4\0", |
| ]; |
| |
| const X86_WHITELIST: &'static [&'static str] = &[ |
| "avx\0", |
| "avx2\0", |
| "bmi\0", |
| "bmi2\0", |
| "sse\0", |
| "sse2\0", |
| "sse3\0", |
| "sse4.1\0", |
| "sse4.2\0", |
| "ssse3\0", |
| "tbm\0", |
| ]; |
| |
| /// Add `target_feature = "..."` cfgs for a variety of platform |
| /// specific features (SSE, NEON etc.). |
| /// |
| /// This is performed by checking whether a whitelisted set of |
| /// features is available on the target machine, by querying LLVM. |
| pub fn add_configuration(cfg: &mut ast::CrateConfig, sess: &Session) { |
| let target_machine = create_target_machine(sess); |
| |
| let whitelist = match &*sess.target.target.arch { |
| "arm" => ARM_WHITELIST, |
| "x86" | "x86_64" => X86_WHITELIST, |
| _ => &[], |
| }; |
| |
| let tf = InternedString::new("target_feature"); |
| for feat in whitelist { |
| assert_eq!(feat.chars().last(), Some('\0')); |
| if unsafe { LLVMRustHasFeature(target_machine, feat.as_ptr() as *const c_char) } { |
| cfg.push(attr::mk_name_value_item_str(tf.clone(), intern(&feat[..feat.len()-1]))) |
| } |
| } |
| } |