// Copyright 2012-2016 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. use llvm::{self, ValueRef, AttributePlace}; use base; use builder::Builder; use common::{ty_fn_sig, C_usize}; use context::CodegenCx; use cabi_x86; use cabi_x86_64; use cabi_x86_win64; use cabi_arm; use cabi_aarch64; use cabi_powerpc; use cabi_powerpc64; use cabi_s390x; use cabi_mips; use cabi_mips64; use cabi_asmjs; use cabi_msp430; use cabi_sparc; use cabi_sparc64; use cabi_nvptx; use cabi_nvptx64; use cabi_hexagon; use mir::place::PlaceRef; use mir::operand::OperandValue; use type_::Type; use type_of::{LayoutLlvmExt, PointerKind}; use rustc::ty::{self, Ty}; use rustc::ty::layout::{self, Align, Size, TyLayout}; use rustc::ty::layout::{HasDataLayout, LayoutOf}; use libc::c_uint; use std::{cmp, iter}; pub use syntax::abi::Abi; pub use rustc::ty::layout::{FAT_PTR_ADDR, FAT_PTR_EXTRA}; #[derive(Clone, Copy, PartialEq, Eq, Debug)] pub enum PassMode { /// Ignore the argument (useful for empty struct). Ignore, /// Pass the argument directly. Direct(ArgAttributes), /// Pass a pair's elements directly in two arguments. Pair(ArgAttributes, ArgAttributes), /// Pass the argument after casting it, to either /// a single uniform or a pair of registers. Cast(CastTarget), /// Pass the argument indirectly via a hidden pointer. Indirect(ArgAttributes), } // Hack to disable non_upper_case_globals only for the bitflags! and not for the rest // of this module pub use self::attr_impl::ArgAttribute; #[allow(non_upper_case_globals)] #[allow(unused)] mod attr_impl { // The subset of llvm::Attribute needed for arguments, packed into a bitfield. bitflags! { #[derive(Default)] pub struct ArgAttribute: u16 { const ByVal = 1 << 0; const NoAlias = 1 << 1; const NoCapture = 1 << 2; const NonNull = 1 << 3; const ReadOnly = 1 << 4; const SExt = 1 << 5; const StructRet = 1 << 6; const ZExt = 1 << 7; const InReg = 1 << 8; } } } macro_rules! for_each_kind { ($flags: ident, $f: ident, $($kind: ident),+) => ({ $(if $flags.contains(ArgAttribute::$kind) { $f(llvm::Attribute::$kind) })+ }) } impl ArgAttribute { fn for_each_kind(&self, mut f: F) where F: FnMut(llvm::Attribute) { for_each_kind!(self, f, ByVal, NoAlias, NoCapture, NonNull, ReadOnly, SExt, StructRet, ZExt, InReg) } } /// A compact representation of LLVM attributes (at least those relevant for this module) /// that can be manipulated without interacting with LLVM's Attribute machinery. #[derive(Copy, Clone, PartialEq, Eq, Debug)] pub struct ArgAttributes { regular: ArgAttribute, pointee_size: Size, pointee_align: Option } impl ArgAttributes { fn new() -> Self { ArgAttributes { regular: ArgAttribute::default(), pointee_size: Size::from_bytes(0), pointee_align: None, } } pub fn set(&mut self, attr: ArgAttribute) -> &mut Self { self.regular = self.regular | attr; self } pub fn contains(&self, attr: ArgAttribute) -> bool { self.regular.contains(attr) } pub fn apply_llfn(&self, idx: AttributePlace, llfn: ValueRef) { let mut regular = self.regular; unsafe { let deref = self.pointee_size.bytes(); if deref != 0 { if regular.contains(ArgAttribute::NonNull) { llvm::LLVMRustAddDereferenceableAttr(llfn, idx.as_uint(), deref); } else { llvm::LLVMRustAddDereferenceableOrNullAttr(llfn, idx.as_uint(), deref); } regular -= ArgAttribute::NonNull; } if let Some(align) = self.pointee_align { llvm::LLVMRustAddAlignmentAttr(llfn, idx.as_uint(), align.abi() as u32); } regular.for_each_kind(|attr| attr.apply_llfn(idx, llfn)); } } pub fn apply_callsite(&self, idx: AttributePlace, callsite: ValueRef) { let mut regular = self.regular; unsafe { let deref = self.pointee_size.bytes(); if deref != 0 { if regular.contains(ArgAttribute::NonNull) { llvm::LLVMRustAddDereferenceableCallSiteAttr(callsite, idx.as_uint(), deref); } else { llvm::LLVMRustAddDereferenceableOrNullCallSiteAttr(callsite, idx.as_uint(), deref); } regular -= ArgAttribute::NonNull; } if let Some(align) = self.pointee_align { llvm::LLVMRustAddAlignmentCallSiteAttr(callsite, idx.as_uint(), align.abi() as u32); } regular.for_each_kind(|attr| attr.apply_callsite(idx, callsite)); } } } #[derive(Copy, Clone, PartialEq, Eq, Debug)] pub enum RegKind { Integer, Float, Vector } #[derive(Copy, Clone, PartialEq, Eq, Debug)] pub struct Reg { pub kind: RegKind, pub size: Size, } macro_rules! reg_ctor { ($name:ident, $kind:ident, $bits:expr) => { pub fn $name() -> Reg { Reg { kind: RegKind::$kind, size: Size::from_bits($bits) } } } } impl Reg { reg_ctor!(i8, Integer, 8); reg_ctor!(i16, Integer, 16); reg_ctor!(i32, Integer, 32); reg_ctor!(i64, Integer, 64); reg_ctor!(f32, Float, 32); reg_ctor!(f64, Float, 64); } impl Reg { pub fn align(&self, cx: &CodegenCx) -> Align { let dl = cx.data_layout(); match self.kind { RegKind::Integer => { match self.size.bits() { 1 => dl.i1_align, 2...8 => dl.i8_align, 9...16 => dl.i16_align, 17...32 => dl.i32_align, 33...64 => dl.i64_align, 65...128 => dl.i128_align, _ => bug!("unsupported integer: {:?}", self) } } RegKind::Float => { match self.size.bits() { 32 => dl.f32_align, 64 => dl.f64_align, _ => bug!("unsupported float: {:?}", self) } } RegKind::Vector => dl.vector_align(self.size) } } pub fn llvm_type(&self, cx: &CodegenCx) -> Type { match self.kind { RegKind::Integer => Type::ix(cx, self.size.bits()), RegKind::Float => { match self.size.bits() { 32 => Type::f32(cx), 64 => Type::f64(cx), _ => bug!("unsupported float: {:?}", self) } } RegKind::Vector => { Type::vector(&Type::i8(cx), self.size.bytes()) } } } } /// An argument passed entirely registers with the /// same kind (e.g. HFA / HVA on PPC64 and AArch64). #[derive(Clone, Copy, PartialEq, Eq, Debug)] pub struct Uniform { pub unit: Reg, /// The total size of the argument, which can be: /// * equal to `unit.size` (one scalar/vector) /// * a multiple of `unit.size` (an array of scalar/vectors) /// * if `unit.kind` is `Integer`, the last element /// can be shorter, i.e. `{ i64, i64, i32 }` for /// 64-bit integers with a total size of 20 bytes pub total: Size, } impl From for Uniform { fn from(unit: Reg) -> Uniform { Uniform { unit, total: unit.size } } } impl Uniform { pub fn align(&self, cx: &CodegenCx) -> Align { self.unit.align(cx) } pub fn llvm_type(&self, cx: &CodegenCx) -> Type { let llunit = self.unit.llvm_type(cx); if self.total <= self.unit.size { return llunit; } let count = self.total.bytes() / self.unit.size.bytes(); let rem_bytes = self.total.bytes() % self.unit.size.bytes(); if rem_bytes == 0 { return Type::array(&llunit, count); } // Only integers can be really split further. assert_eq!(self.unit.kind, RegKind::Integer); let args: Vec<_> = (0..count).map(|_| llunit) .chain(iter::once(Type::ix(cx, rem_bytes * 8))) .collect(); Type::struct_(cx, &args, false) } } pub trait LayoutExt<'tcx> { fn is_aggregate(&self) -> bool; fn homogeneous_aggregate<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> Option; } impl<'tcx> LayoutExt<'tcx> for TyLayout<'tcx> { fn is_aggregate(&self) -> bool { match self.abi { layout::Abi::Uninhabited | layout::Abi::Scalar(_) | layout::Abi::Vector { .. } => false, layout::Abi::ScalarPair(..) | layout::Abi::Aggregate { .. } => true } } fn homogeneous_aggregate<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> Option { match self.abi { layout::Abi::Uninhabited => None, // The primitive for this algorithm. layout::Abi::Scalar(ref scalar) => { let kind = match scalar.value { layout::Int(..) | layout::Pointer => RegKind::Integer, layout::F32 | layout::F64 => RegKind::Float }; Some(Reg { kind, size: self.size }) } layout::Abi::Vector { .. } => { Some(Reg { kind: RegKind::Vector, size: self.size }) } layout::Abi::ScalarPair(..) | layout::Abi::Aggregate { .. } => { let mut total = Size::from_bytes(0); let mut result = None; let is_union = match self.fields { layout::FieldPlacement::Array { count, .. } => { if count > 0 { return self.field(cx, 0).homogeneous_aggregate(cx); } else { return None; } } layout::FieldPlacement::Union(_) => true, layout::FieldPlacement::Arbitrary { .. } => false }; for i in 0..self.fields.count() { if !is_union && total != self.fields.offset(i) { return None; } let field = self.field(cx, i); match (result, field.homogeneous_aggregate(cx)) { // The field itself must be a homogeneous aggregate. (_, None) => return None, // If this is the first field, record the unit. (None, Some(unit)) => { result = Some(unit); } // For all following fields, the unit must be the same. (Some(prev_unit), Some(unit)) => { if prev_unit != unit { return None; } } } // Keep track of the offset (without padding). let size = field.size; if is_union { total = cmp::max(total, size); } else { total += size; } } // There needs to be no padding. if total != self.size { None } else { result } } } } } #[derive(Clone, Copy, PartialEq, Eq, Debug)] pub enum CastTarget { Uniform(Uniform), Pair(Reg, Reg) } impl From for CastTarget { fn from(unit: Reg) -> CastTarget { CastTarget::Uniform(Uniform::from(unit)) } } impl From for CastTarget { fn from(uniform: Uniform) -> CastTarget { CastTarget::Uniform(uniform) } } impl CastTarget { pub fn size(&self, cx: &CodegenCx) -> Size { match *self { CastTarget::Uniform(u) => u.total, CastTarget::Pair(a, b) => { (a.size.abi_align(a.align(cx)) + b.size) .abi_align(self.align(cx)) } } } pub fn align(&self, cx: &CodegenCx) -> Align { match *self { CastTarget::Uniform(u) => u.align(cx), CastTarget::Pair(a, b) => { cx.data_layout().aggregate_align .max(a.align(cx)) .max(b.align(cx)) } } } pub fn llvm_type(&self, cx: &CodegenCx) -> Type { match *self { CastTarget::Uniform(u) => u.llvm_type(cx), CastTarget::Pair(a, b) => { Type::struct_(cx, &[ a.llvm_type(cx), b.llvm_type(cx) ], false) } } } } /// Information about how to pass an argument to, /// or return a value from, a function, under some ABI. #[derive(Debug)] pub struct ArgType<'tcx> { pub layout: TyLayout<'tcx>, /// Dummy argument, which is emitted before the real argument. pub pad: Option, pub mode: PassMode, } impl<'a, 'tcx> ArgType<'tcx> { fn new(layout: TyLayout<'tcx>) -> ArgType<'tcx> { ArgType { layout, pad: None, mode: PassMode::Direct(ArgAttributes::new()), } } pub fn make_indirect(&mut self) { assert_eq!(self.mode, PassMode::Direct(ArgAttributes::new())); // Start with fresh attributes for the pointer. let mut attrs = ArgAttributes::new(); // For non-immediate arguments the callee gets its own copy of // the value on the stack, so there are no aliases. It's also // program-invisible so can't possibly capture attrs.set(ArgAttribute::NoAlias) .set(ArgAttribute::NoCapture) .set(ArgAttribute::NonNull); attrs.pointee_size = self.layout.size; // FIXME(eddyb) We should be doing this, but at least on // i686-pc-windows-msvc, it results in wrong stack offsets. // attrs.pointee_align = Some(self.layout.align); self.mode = PassMode::Indirect(attrs); } pub fn make_indirect_byval(&mut self) { self.make_indirect(); match self.mode { PassMode::Indirect(ref mut attrs) => { attrs.set(ArgAttribute::ByVal); } _ => bug!() } } pub fn extend_integer_width_to(&mut self, bits: u64) { // Only integers have signedness if let layout::Abi::Scalar(ref scalar) = self.layout.abi { if let layout::Int(i, signed) = scalar.value { if i.size().bits() < bits { if let PassMode::Direct(ref mut attrs) = self.mode { attrs.set(if signed { ArgAttribute::SExt } else { ArgAttribute::ZExt }); } } } } } pub fn cast_to>(&mut self, target: T) { assert_eq!(self.mode, PassMode::Direct(ArgAttributes::new())); self.mode = PassMode::Cast(target.into()); } pub fn pad_with(&mut self, reg: Reg) { self.pad = Some(reg); } pub fn is_indirect(&self) -> bool { match self.mode { PassMode::Indirect(_) => true, _ => false } } pub fn is_ignore(&self) -> bool { self.mode == PassMode::Ignore } /// Get the LLVM type for an place of the original Rust type of /// this argument/return, i.e. the result of `type_of::type_of`. pub fn memory_ty(&self, cx: &CodegenCx<'a, 'tcx>) -> Type { self.layout.llvm_type(cx) } /// Store a direct/indirect value described by this ArgType into a /// place for the original Rust type of this argument/return. /// Can be used for both storing formal arguments into Rust variables /// or results of call/invoke instructions into their destinations. pub fn store(&self, bx: &Builder<'a, 'tcx>, val: ValueRef, dst: PlaceRef<'tcx>) { if self.is_ignore() { return; } let cx = bx.cx; if self.is_indirect() { OperandValue::Ref(val, self.layout.align).store(bx, dst) } else if let PassMode::Cast(cast) = self.mode { // FIXME(eddyb): Figure out when the simpler Store is safe, clang // uses it for i16 -> {i8, i8}, but not for i24 -> {i8, i8, i8}. let can_store_through_cast_ptr = false; if can_store_through_cast_ptr { let cast_dst = bx.pointercast(dst.llval, cast.llvm_type(cx).ptr_to()); bx.store(val, cast_dst, self.layout.align); } else { // The actual return type is a struct, but the ABI // adaptation code has cast it into some scalar type. The // code that follows is the only reliable way I have // found to do a transform like i64 -> {i32,i32}. // Basically we dump the data onto the stack then memcpy it. // // Other approaches I tried: // - Casting rust ret pointer to the foreign type and using Store // is (a) unsafe if size of foreign type > size of rust type and // (b) runs afoul of strict aliasing rules, yielding invalid // assembly under -O (specifically, the store gets removed). // - Truncating foreign type to correct integral type and then // bitcasting to the struct type yields invalid cast errors. // We instead thus allocate some scratch space... let scratch_size = cast.size(cx); let scratch_align = cast.align(cx); let llscratch = bx.alloca(cast.llvm_type(cx), "abi_cast", scratch_align); bx.lifetime_start(llscratch, scratch_size); // ...where we first store the value... bx.store(val, llscratch, scratch_align); // ...and then memcpy it to the intended destination. base::call_memcpy(bx, bx.pointercast(dst.llval, Type::i8p(cx)), bx.pointercast(llscratch, Type::i8p(cx)), C_usize(cx, self.layout.size.bytes()), self.layout.align.min(scratch_align)); bx.lifetime_end(llscratch, scratch_size); } } else { OperandValue::Immediate(val).store(bx, dst); } } pub fn store_fn_arg(&self, bx: &Builder<'a, 'tcx>, idx: &mut usize, dst: PlaceRef<'tcx>) { let mut next = || { let val = llvm::get_param(bx.llfn(), *idx as c_uint); *idx += 1; val }; match self.mode { PassMode::Ignore => {}, PassMode::Pair(..) => { OperandValue::Pair(next(), next()).store(bx, dst); } PassMode::Direct(_) | PassMode::Indirect(_) | PassMode::Cast(_) => { self.store(bx, next(), dst); } } } } /// 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 #[derive(Debug)] pub struct FnType<'tcx> { /// The LLVM types of each argument. pub args: Vec>, /// LLVM return type. pub ret: ArgType<'tcx>, pub variadic: bool, pub cconv: llvm::CallConv } impl<'a, 'tcx> FnType<'tcx> { pub fn of_instance(cx: &CodegenCx<'a, 'tcx>, instance: &ty::Instance<'tcx>) -> Self { let fn_ty = instance.ty(cx.tcx); let sig = ty_fn_sig(cx, fn_ty); let sig = cx.tcx.erase_late_bound_regions_and_normalize(&sig); FnType::new(cx, sig, &[]) } pub fn new(cx: &CodegenCx<'a, 'tcx>, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> FnType<'tcx> { let mut fn_ty = FnType::unadjusted(cx, sig, extra_args); fn_ty.adjust_for_abi(cx, sig.abi); fn_ty } pub fn new_vtable(cx: &CodegenCx<'a, 'tcx>, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> FnType<'tcx> { let mut fn_ty = FnType::unadjusted(cx, sig, extra_args); // Don't pass the vtable, it's not an argument of the virtual fn. { let self_arg = &mut fn_ty.args[0]; match self_arg.mode { PassMode::Pair(data_ptr, _) => { self_arg.mode = PassMode::Direct(data_ptr); } _ => bug!("FnType::new_vtable: non-pair self {:?}", self_arg) } let pointee = self_arg.layout.ty.builtin_deref(true, ty::NoPreference) .unwrap_or_else(|| { bug!("FnType::new_vtable: non-pointer self {:?}", self_arg) }).ty; let fat_ptr_ty = cx.tcx.mk_mut_ptr(pointee); self_arg.layout = cx.layout_of(fat_ptr_ty).field(cx, 0); } fn_ty.adjust_for_abi(cx, sig.abi); fn_ty } pub fn unadjusted(cx: &CodegenCx<'a, 'tcx>, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> FnType<'tcx> { debug!("FnType::unadjusted({:?}, {:?})", sig, extra_args); use self::Abi::*; let cconv = match cx.sess().target.target.adjust_abi(sig.abi) { RustIntrinsic | PlatformIntrinsic | Rust | RustCall => llvm::CCallConv, // It's the ABI's job to select this, not us. System => bug!("system abi should be selected elsewhere"), Stdcall => llvm::X86StdcallCallConv, Fastcall => llvm::X86FastcallCallConv, Vectorcall => llvm::X86_VectorCall, Thiscall => llvm::X86_ThisCall, C => llvm::CCallConv, Unadjusted => llvm::CCallConv, Win64 => llvm::X86_64_Win64, SysV64 => llvm::X86_64_SysV, Aapcs => llvm::ArmAapcsCallConv, PtxKernel => llvm::PtxKernel, Msp430Interrupt => llvm::Msp430Intr, X86Interrupt => llvm::X86_Intr, // These API constants ought to be more specific... Cdecl => llvm::CCallConv, }; let mut inputs = sig.inputs(); let extra_args = if sig.abi == RustCall { assert!(!sig.variadic && extra_args.is_empty()); match sig.inputs().last().unwrap().sty { ty::TyTuple(ref tupled_arguments, _) => { inputs = &sig.inputs()[0..sig.inputs().len() - 1]; tupled_arguments } _ => { bug!("argument to function with \"rust-call\" ABI \ is not a tuple"); } } } else { assert!(sig.variadic || extra_args.is_empty()); extra_args }; let target = &cx.sess().target.target; let win_x64_gnu = target.target_os == "windows" && target.arch == "x86_64" && target.target_env == "gnu"; let linux_s390x = target.target_os == "linux" && target.arch == "s390x" && target.target_env == "gnu"; let rust_abi = match sig.abi { RustIntrinsic | PlatformIntrinsic | Rust | RustCall => true, _ => false }; // Handle safe Rust thin and fat pointers. let adjust_for_rust_scalar = |attrs: &mut ArgAttributes, scalar: &layout::Scalar, layout: TyLayout<'tcx>, offset: Size, is_return: bool| { // Booleans are always an i1 that needs to be zero-extended. if scalar.is_bool() { attrs.set(ArgAttribute::ZExt); return; } // Only pointer types handled below. if scalar.value != layout::Pointer { return; } if scalar.valid_range.start < scalar.valid_range.end { if scalar.valid_range.start > 0 { attrs.set(ArgAttribute::NonNull); } } if let Some(pointee) = layout.pointee_info_at(cx, offset) { if let Some(kind) = pointee.safe { attrs.pointee_size = pointee.size; attrs.pointee_align = Some(pointee.align); // HACK(eddyb) LLVM inserts `llvm.assume` calls when inlining functions // with align attributes, and those calls later block optimizations. if !is_return { attrs.pointee_align = None; } // `Box` pointer parameters never alias because ownership is transferred // `&mut` pointer parameters never alias other parameters, // or mutable global data // // `&T` where `T` contains no `UnsafeCell` is immutable, // and can be marked as both `readonly` and `noalias`, as // LLVM's definition of `noalias` is based solely on memory // dependencies rather than pointer equality let no_alias = match kind { PointerKind::Shared => false, PointerKind::UniqueOwned => true, PointerKind::Frozen | PointerKind::UniqueBorrowed => !is_return }; if no_alias { attrs.set(ArgAttribute::NoAlias); } if kind == PointerKind::Frozen && !is_return { attrs.set(ArgAttribute::ReadOnly); } } } }; let arg_of = |ty: Ty<'tcx>, is_return: bool| { let mut arg = ArgType::new(cx.layout_of(ty)); if arg.layout.is_zst() { // For some forsaken reason, x86_64-pc-windows-gnu // doesn't ignore zero-sized struct arguments. // The same is true for s390x-unknown-linux-gnu. if is_return || rust_abi || (!win_x64_gnu && !linux_s390x) { arg.mode = PassMode::Ignore; } } // FIXME(eddyb) other ABIs don't have logic for scalar pairs. if !is_return && rust_abi { if let layout::Abi::ScalarPair(ref a, ref b) = arg.layout.abi { let mut a_attrs = ArgAttributes::new(); let mut b_attrs = ArgAttributes::new(); adjust_for_rust_scalar(&mut a_attrs, a, arg.layout, Size::from_bytes(0), false); adjust_for_rust_scalar(&mut b_attrs, b, arg.layout, a.value.size(cx).abi_align(b.value.align(cx)), false); arg.mode = PassMode::Pair(a_attrs, b_attrs); return arg; } } if let layout::Abi::Scalar(ref scalar) = arg.layout.abi { if let PassMode::Direct(ref mut attrs) = arg.mode { adjust_for_rust_scalar(attrs, scalar, arg.layout, Size::from_bytes(0), is_return); } } arg }; FnType { ret: arg_of(sig.output(), true), args: inputs.iter().chain(extra_args.iter()).map(|ty| { arg_of(ty, false) }).collect(), variadic: sig.variadic, cconv, } } fn adjust_for_abi(&mut self, cx: &CodegenCx<'a, 'tcx>, abi: Abi) { if abi == Abi::Unadjusted { return } if abi == Abi::Rust || abi == Abi::RustCall || abi == Abi::RustIntrinsic || abi == Abi::PlatformIntrinsic { let fixup = |arg: &mut ArgType<'tcx>| { if arg.is_ignore() { return; } match arg.layout.abi { layout::Abi::Aggregate { .. } => {} _ => return } let size = arg.layout.size; if size > layout::Pointer.size(cx) { arg.make_indirect(); } else { // We want to pass small aggregates as immediates, but using // a LLVM aggregate type for this leads to bad optimizations, // so we pick an appropriately sized integer type instead. arg.cast_to(Reg { kind: RegKind::Integer, size }); } }; fixup(&mut self.ret); for arg in &mut self.args { fixup(arg); } if let PassMode::Indirect(ref mut attrs) = self.ret.mode { attrs.set(ArgAttribute::StructRet); } return; } match &cx.sess().target.target.arch[..] { "x86" => { let flavor = if abi == Abi::Fastcall { cabi_x86::Flavor::Fastcall } else { cabi_x86::Flavor::General }; cabi_x86::compute_abi_info(cx, self, flavor); }, "x86_64" => if abi == Abi::SysV64 { cabi_x86_64::compute_abi_info(cx, self); } else if abi == Abi::Win64 || cx.sess().target.target.options.is_like_windows { cabi_x86_win64::compute_abi_info(self); } else { cabi_x86_64::compute_abi_info(cx, self); }, "aarch64" => cabi_aarch64::compute_abi_info(cx, self), "arm" => cabi_arm::compute_abi_info(cx, self), "mips" => cabi_mips::compute_abi_info(cx, self), "mips64" => cabi_mips64::compute_abi_info(cx, self), "powerpc" => cabi_powerpc::compute_abi_info(cx, self), "powerpc64" => cabi_powerpc64::compute_abi_info(cx, self), "s390x" => cabi_s390x::compute_abi_info(cx, self), "asmjs" => cabi_asmjs::compute_abi_info(cx, self), "wasm32" => cabi_asmjs::compute_abi_info(cx, self), "msp430" => cabi_msp430::compute_abi_info(self), "sparc" => cabi_sparc::compute_abi_info(cx, self), "sparc64" => cabi_sparc64::compute_abi_info(cx, self), "nvptx" => cabi_nvptx::compute_abi_info(self), "nvptx64" => cabi_nvptx64::compute_abi_info(self), "hexagon" => cabi_hexagon::compute_abi_info(self), a => cx.sess().fatal(&format!("unrecognized arch \"{}\" in target specification", a)) } if let PassMode::Indirect(ref mut attrs) = self.ret.mode { attrs.set(ArgAttribute::StructRet); } } pub fn llvm_type(&self, cx: &CodegenCx<'a, 'tcx>) -> Type { let mut llargument_tys = Vec::new(); let llreturn_ty = match self.ret.mode { PassMode::Ignore => Type::void(cx), PassMode::Direct(_) | PassMode::Pair(..) => { self.ret.layout.immediate_llvm_type(cx) } PassMode::Cast(cast) => cast.llvm_type(cx), PassMode::Indirect(_) => { llargument_tys.push(self.ret.memory_ty(cx).ptr_to()); Type::void(cx) } }; for arg in &self.args { // add padding if let Some(ty) = arg.pad { llargument_tys.push(ty.llvm_type(cx)); } let llarg_ty = match arg.mode { PassMode::Ignore => continue, PassMode::Direct(_) => arg.layout.immediate_llvm_type(cx), PassMode::Pair(..) => { llargument_tys.push(arg.layout.scalar_pair_element_llvm_type(cx, 0)); llargument_tys.push(arg.layout.scalar_pair_element_llvm_type(cx, 1)); continue; } PassMode::Cast(cast) => cast.llvm_type(cx), PassMode::Indirect(_) => arg.memory_ty(cx).ptr_to(), }; llargument_tys.push(llarg_ty); } if self.variadic { Type::variadic_func(&llargument_tys, &llreturn_ty) } else { Type::func(&llargument_tys, &llreturn_ty) } } pub fn apply_attrs_llfn(&self, llfn: ValueRef) { let mut i = 0; let mut apply = |attrs: &ArgAttributes| { attrs.apply_llfn(llvm::AttributePlace::Argument(i), llfn); i += 1; }; match self.ret.mode { PassMode::Direct(ref attrs) => { attrs.apply_llfn(llvm::AttributePlace::ReturnValue, llfn); } PassMode::Indirect(ref attrs) => apply(attrs), _ => {} } for arg in &self.args { if arg.pad.is_some() { apply(&ArgAttributes::new()); } match arg.mode { PassMode::Ignore => {} PassMode::Direct(ref attrs) | PassMode::Indirect(ref attrs) => apply(attrs), PassMode::Pair(ref a, ref b) => { apply(a); apply(b); } PassMode::Cast(_) => apply(&ArgAttributes::new()), } } } pub fn apply_attrs_callsite(&self, callsite: ValueRef) { let mut i = 0; let mut apply = |attrs: &ArgAttributes| { attrs.apply_callsite(llvm::AttributePlace::Argument(i), callsite); i += 1; }; match self.ret.mode { PassMode::Direct(ref attrs) => { attrs.apply_callsite(llvm::AttributePlace::ReturnValue, callsite); } PassMode::Indirect(ref attrs) => apply(attrs), _ => {} } for arg in &self.args { if arg.pad.is_some() { apply(&ArgAttributes::new()); } match arg.mode { PassMode::Ignore => {} PassMode::Direct(ref attrs) | PassMode::Indirect(ref attrs) => apply(attrs), PassMode::Pair(ref a, ref b) => { apply(a); apply(b); } PassMode::Cast(_) => apply(&ArgAttributes::new()), } } if self.cconv != llvm::CCallConv { llvm::SetInstructionCallConv(callsite, self.cconv); } } }