| // Copyright 2012-2013 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. |
| |
| #![allow(non_upper_case_globals)] |
| |
| use llvm::{Integer, Pointer, Float, Double, Struct, Array, Vector}; |
| use abi::{FnType, ArgType}; |
| use context::CrateContext; |
| use type_::Type; |
| |
| use std::cmp; |
| |
| pub enum Flavor { |
| General, |
| Ios |
| } |
| |
| type TyAlignFn = fn(ty: Type) -> usize; |
| |
| fn align_up_to(off: usize, a: usize) -> usize { |
| return (off + a - 1) / a * a; |
| } |
| |
| fn align(off: usize, ty: Type, align_fn: TyAlignFn) -> usize { |
| let a = align_fn(ty); |
| return align_up_to(off, a); |
| } |
| |
| fn general_ty_align(ty: Type) -> usize { |
| match ty.kind() { |
| Integer => ((ty.int_width() as usize) + 7) / 8, |
| Pointer => 4, |
| Float => 4, |
| Double => 8, |
| Struct => { |
| if ty.is_packed() { |
| 1 |
| } else { |
| let str_tys = ty.field_types(); |
| str_tys.iter().fold(1, |a, t| cmp::max(a, general_ty_align(*t))) |
| } |
| } |
| Array => { |
| let elt = ty.element_type(); |
| general_ty_align(elt) |
| } |
| Vector => { |
| let len = ty.vector_length(); |
| let elt = ty.element_type(); |
| general_ty_align(elt) * len |
| } |
| _ => bug!("ty_align: unhandled type") |
| } |
| } |
| |
| // For more information see: |
| // ARMv7 |
| // https://developer.apple.com/library/ios/documentation/Xcode/Conceptual |
| // /iPhoneOSABIReference/Articles/ARMv7FunctionCallingConventions.html |
| // ARMv6 |
| // https://developer.apple.com/library/ios/documentation/Xcode/Conceptual |
| // /iPhoneOSABIReference/Articles/ARMv6FunctionCallingConventions.html |
| fn ios_ty_align(ty: Type) -> usize { |
| match ty.kind() { |
| Integer => cmp::min(4, ((ty.int_width() as usize) + 7) / 8), |
| Pointer => 4, |
| Float => 4, |
| Double => 4, |
| Struct => { |
| if ty.is_packed() { |
| 1 |
| } else { |
| let str_tys = ty.field_types(); |
| str_tys.iter().fold(1, |a, t| cmp::max(a, ios_ty_align(*t))) |
| } |
| } |
| Array => { |
| let elt = ty.element_type(); |
| ios_ty_align(elt) |
| } |
| Vector => { |
| let len = ty.vector_length(); |
| let elt = ty.element_type(); |
| ios_ty_align(elt) * len |
| } |
| _ => bug!("ty_align: unhandled type") |
| } |
| } |
| |
| fn ty_size(ty: Type, align_fn: TyAlignFn) -> usize { |
| match ty.kind() { |
| Integer => ((ty.int_width() as usize) + 7) / 8, |
| Pointer => 4, |
| Float => 4, |
| Double => 8, |
| Struct => { |
| if ty.is_packed() { |
| let str_tys = ty.field_types(); |
| str_tys.iter().fold(0, |s, t| s + ty_size(*t, align_fn)) |
| } else { |
| let str_tys = ty.field_types(); |
| let size = str_tys.iter() |
| .fold(0, |s, t| { |
| align(s, *t, align_fn) + ty_size(*t, align_fn) |
| }); |
| align(size, ty, align_fn) |
| } |
| } |
| Array => { |
| let len = ty.array_length(); |
| let elt = ty.element_type(); |
| let eltsz = ty_size(elt, align_fn); |
| len * eltsz |
| } |
| Vector => { |
| let len = ty.vector_length(); |
| let elt = ty.element_type(); |
| let eltsz = ty_size(elt, align_fn); |
| len * eltsz |
| } |
| _ => bug!("ty_size: unhandled type") |
| } |
| } |
| |
| fn classify_ret_ty(ccx: &CrateContext, ret: &mut ArgType, align_fn: TyAlignFn) { |
| if is_reg_ty(ret.ty) { |
| ret.extend_integer_width_to(32); |
| return; |
| } |
| let size = ty_size(ret.ty, align_fn); |
| if size <= 4 { |
| let llty = if size <= 1 { |
| Type::i8(ccx) |
| } else if size <= 2 { |
| Type::i16(ccx) |
| } else { |
| Type::i32(ccx) |
| }; |
| ret.cast = Some(llty); |
| return; |
| } |
| ret.make_indirect(ccx); |
| } |
| |
| fn classify_arg_ty(ccx: &CrateContext, arg: &mut ArgType, align_fn: TyAlignFn) { |
| if is_reg_ty(arg.ty) { |
| arg.extend_integer_width_to(32); |
| return; |
| } |
| let align = align_fn(arg.ty); |
| let size = ty_size(arg.ty, align_fn); |
| let llty = if align <= 4 { |
| Type::array(&Type::i32(ccx), ((size + 3) / 4) as u64) |
| } else { |
| Type::array(&Type::i64(ccx), ((size + 7) / 8) as u64) |
| }; |
| arg.cast = Some(llty); |
| } |
| |
| fn is_reg_ty(ty: Type) -> bool { |
| match ty.kind() { |
| Integer |
| | Pointer |
| | Float |
| | Double |
| | Vector => true, |
| _ => false |
| } |
| } |
| |
| pub fn compute_abi_info(ccx: &CrateContext, fty: &mut FnType, flavor: Flavor) { |
| let align_fn = match flavor { |
| Flavor::General => general_ty_align as TyAlignFn, |
| Flavor::Ios => ios_ty_align as TyAlignFn, |
| }; |
| |
| if !fty.ret.is_ignore() { |
| classify_ret_ty(ccx, &mut fty.ret, align_fn); |
| } |
| |
| for arg in &mut fty.args { |
| if arg.is_ignore() { continue; } |
| classify_arg_ty(ccx, arg, align_fn); |
| } |
| } |