rust/src/librustc/middle/trans/cabi.rs
2013-12-26 13:01:26 -08:00

103 lines
3.0 KiB
Rust

// Copyright 2012 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 lib::llvm::Attribute;
use std::option;
use middle::trans::context::CrateContext;
use middle::trans::cabi_x86;
use middle::trans::cabi_x86_64;
use middle::trans::cabi_arm;
use middle::trans::cabi_mips;
use middle::trans::type_::Type;
use syntax::abi::{X86, X86_64, Arm, Mips};
#[deriving(Clone, Eq)]
pub enum ArgKind {
/// Pass the argument directly using the normal converted
/// LLVM type or by coercing to another specified type
Direct,
/// Pass the argument indirectly via a hidden pointer
Indirect
}
/// Information about how a specific C type
/// should be passed to or returned from a function
///
/// This is borrowed from clang's ABIInfo.h
#[deriving(Clone)]
pub struct ArgType {
kind: ArgKind,
/// Original LLVM type
ty: Type,
/// Coerced LLVM Type
cast: option::Option<Type>,
/// Dummy argument, which is emitted before the real argument
pad: option::Option<Type>,
/// LLVM attribute of argument
attr: option::Option<Attribute>
}
impl ArgType {
pub fn direct(ty: Type, cast: option::Option<Type>,
pad: option::Option<Type>,
attr: option::Option<Attribute>) -> ArgType {
ArgType {
kind: Direct,
ty: ty,
cast: cast,
pad: pad,
attr: attr
}
}
pub fn indirect(ty: Type, attr: option::Option<Attribute>) -> ArgType {
ArgType {
kind: Indirect,
ty: ty,
cast: option::None,
pad: option::None,
attr: attr
}
}
pub fn is_direct(&self) -> bool {
return self.kind == Direct;
}
pub fn is_indirect(&self) -> bool {
return self.kind == Indirect;
}
}
/// Metadata describing how the arguments to a native function
/// should be passed in order to respect the native ABI.
///
/// I will do my best to describe this structure, but these
/// comments are reverse-engineered and may be inaccurate. -NDM
pub struct FnType {
/// The LLVM types of each argument.
arg_tys: ~[ArgType],
/// LLVM return type.
ret_ty: ArgType,
}
pub fn compute_abi_info(ccx: &CrateContext,
atys: &[Type],
rty: Type,
ret_def: bool) -> FnType {
match ccx.sess.targ_cfg.arch {
X86 => cabi_x86::compute_abi_info(ccx, atys, rty, ret_def),
X86_64 => cabi_x86_64::compute_abi_info(ccx, atys, rty, ret_def),
Arm => cabi_arm::compute_abi_info(ccx, atys, rty, ret_def),
Mips => cabi_mips::compute_abi_info(ccx, atys, rty, ret_def),
}
}