use rustc_codegen_ssa::traits::*;
-use rustc_target::abi::{HasDataLayout, LayoutOf, Size, TyLayout, Abi as LayoutAbi};
-use rustc::ty::{self, Ty, Instance};
-use rustc::ty::layout::{self, PointerKind};
+use rustc_target::abi::{HasDataLayout, LayoutOf};
+use rustc::ty::{Ty};
+use rustc::ty::layout::{self};
use libc::c_uint;
}
}
-pub trait FnTypeExt<'tcx> {
- fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>) -> Self;
- fn new(cx: &CodegenCx<'ll, 'tcx>,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>]) -> Self;
- fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>]) -> Self;
- fn new_internal(
- cx: &CodegenCx<'ll, 'tcx>,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>],
- mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
- ) -> Self;
- fn adjust_for_abi(&mut self,
- cx: &CodegenCx<'ll, 'tcx>,
- abi: Abi);
+pub trait FnTypeLlvmExt<'tcx> {
fn llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
fn ptr_to_llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
fn llvm_cconv(&self) -> llvm::CallConv;
fn apply_attrs_callsite(&self, bx: &mut Builder<'a, 'll, 'tcx>, callsite: &'ll Value);
}
-impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
- fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>) -> Self {
- let sig = instance.fn_sig(cx.tcx);
- let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
- FnType::new(cx, sig, &[])
- }
-
- fn new(cx: &CodegenCx<'ll, 'tcx>,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>]) -> Self {
- FnType::new_internal(cx, sig, extra_args, |ty, _| {
- ArgType::new(cx.layout_of(ty))
- })
- }
-
- fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>]) -> Self {
- FnType::new_internal(cx, sig, extra_args, |ty, arg_idx| {
- let mut layout = cx.layout_of(ty);
- // Don't pass the vtable, it's not an argument of the virtual fn.
- // Instead, pass just the data pointer, but give it the type `*const/mut dyn Trait`
- // or `&/&mut dyn Trait` because this is special-cased elsewhere in codegen
- if arg_idx == Some(0) {
- let fat_pointer_ty = if layout.is_unsized() {
- // unsized `self` is passed as a pointer to `self`
- // FIXME (mikeyhew) change this to use &own if it is ever added to the language
- cx.tcx.mk_mut_ptr(layout.ty)
- } else {
- match layout.abi {
- LayoutAbi::ScalarPair(..) => (),
- _ => bug!("receiver type has unsupported layout: {:?}", layout)
- }
-
- // In the case of Rc<Self>, we need to explicitly pass a *mut RcBox<Self>
- // with a Scalar (not ScalarPair) ABI. This is a hack that is understood
- // elsewhere in the compiler as a method on a `dyn Trait`.
- // To get the type `*mut RcBox<Self>`, we just keep unwrapping newtypes until we
- // get a built-in pointer type
- let mut fat_pointer_layout = layout;
- 'descend_newtypes: while !fat_pointer_layout.ty.is_unsafe_ptr()
- && !fat_pointer_layout.ty.is_region_ptr()
- {
- 'iter_fields: for i in 0..fat_pointer_layout.fields.count() {
- let field_layout = fat_pointer_layout.field(cx, i);
-
- if !field_layout.is_zst() {
- fat_pointer_layout = field_layout;
- continue 'descend_newtypes
- }
- }
-
- bug!("receiver has no non-zero-sized fields {:?}", fat_pointer_layout);
- }
-
- fat_pointer_layout.ty
- };
-
- // we now have a type like `*mut RcBox<dyn Trait>`
- // change its layout to that of `*mut ()`, a thin pointer, but keep the same type
- // this is understood as a special case elsewhere in the compiler
- let unit_pointer_ty = cx.tcx.mk_mut_ptr(cx.tcx.mk_unit());
- layout = cx.layout_of(unit_pointer_ty);
- layout.ty = fat_pointer_ty;
- }
- ArgType::new(layout)
- })
- }
-
- fn new_internal(
- cx: &CodegenCx<'ll, 'tcx>,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>],
- mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
- ) -> Self {
- debug!("FnType::new_internal({:?}, {:?})", sig, extra_args);
-
- use self::Abi::*;
- let conv = match cx.sess().target.target.adjust_abi(sig.abi) {
- RustIntrinsic | PlatformIntrinsic |
- Rust | RustCall => Conv::C,
-
- // It's the ABI's job to select this, not ours.
- System => bug!("system abi should be selected elsewhere"),
-
- Stdcall => Conv::X86Stdcall,
- Fastcall => Conv::X86Fastcall,
- Vectorcall => Conv::X86VectorCall,
- Thiscall => Conv::X86ThisCall,
- C => Conv::C,
- Unadjusted => Conv::C,
- Win64 => Conv::X86_64Win64,
- SysV64 => Conv::X86_64SysV,
- Aapcs => Conv::ArmAapcs,
- PtxKernel => Conv::PtxKernel,
- Msp430Interrupt => Conv::Msp430Intr,
- X86Interrupt => Conv::X86Intr,
- AmdGpuKernel => Conv::AmdGpuKernel,
-
- // These API constants ought to be more specific...
- Cdecl => Conv::C,
- };
-
- let mut inputs = sig.inputs();
- let extra_args = if sig.abi == RustCall {
- assert!(!sig.c_variadic && extra_args.is_empty());
-
- match sig.inputs().last().unwrap().sty {
- ty::Tuple(tupled_arguments) => {
- inputs = &sig.inputs()[0..sig.inputs().len() - 1];
- tupled_arguments.iter().map(|k| k.expect_ty()).collect()
- }
- _ => {
- bug!("argument to function with \"rust-call\" ABI \
- is not a tuple");
- }
- }
- } else {
- assert!(sig.c_variadic || extra_args.is_empty());
- extra_args.to_vec()
- };
-
- 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 linux_sparc64 = target.target_os == "linux"
- && target.arch == "sparc64"
- && 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, Ty<'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);
-
- // `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<U>` 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);
- }
- }
- }
- };
-
- // Store the index of the last argument. This is useful for working with
- // C-compatible variadic arguments.
- let last_arg_idx = if sig.inputs().is_empty() {
- None
- } else {
- Some(sig.inputs().len() - 1)
- };
-
- let arg_of = |ty: Ty<'tcx>, arg_idx: Option<usize>| {
- let is_return = arg_idx.is_none();
- let mut arg = mk_arg_type(ty, arg_idx);
- 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
- // and sparc64-unknown-linux-gnu.
- if is_return || rust_abi || (!win_x64_gnu && !linux_s390x && !linux_sparc64) {
- arg.mode = PassMode::Ignore(IgnoreMode::Zst);
- }
- }
-
- // If this is a C-variadic function, this is not the return value,
- // and there is one or more fixed arguments; ensure that the `VaList`
- // is ignored as an argument.
- if sig.c_variadic {
- match (last_arg_idx, arg_idx) {
- (Some(last_idx), Some(cur_idx)) if last_idx == cur_idx => {
- let va_list_did = match cx.tcx.lang_items().va_list() {
- Some(did) => did,
- None => bug!("`va_list` lang item required for C-variadic functions"),
- };
- match ty.sty {
- ty::Adt(def, _) if def.did == va_list_did => {
- // This is the "spoofed" `VaList`. Set the arguments mode
- // so that it will be ignored.
- arg.mode = PassMode::Ignore(IgnoreMode::CVarArgs);
- },
- _ => (),
- }
- }
- _ => {}
- }
- }
-
- // 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::ZERO,
- false);
- adjust_for_rust_scalar(&mut b_attrs,
- b,
- arg.layout,
- a.value.size(cx).align_to(b.value.align(cx).abi),
- 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::ZERO,
- is_return);
- }
- }
-
- arg
- };
-
- let mut fn_ty = FnType {
- ret: arg_of(sig.output(), None),
- args: inputs.iter().cloned().chain(extra_args).enumerate().map(|(i, ty)| {
- arg_of(ty, Some(i))
- }).collect(),
- c_variadic: sig.c_variadic,
- conv,
- };
- fn_ty.adjust_for_abi(cx, sig.abi);
- fn_ty
- }
-
- fn adjust_for_abi(&mut self,
- cx: &CodegenCx<'ll, '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, Ty<'tcx>>| {
- if arg.is_ignore() { return; }
-
- match arg.layout.abi {
- layout::Abi::Aggregate { .. } => {}
-
- // This is a fun case! The gist of what this is doing is
- // that we want callers and callees to always agree on the
- // ABI of how they pass SIMD arguments. If we were to *not*
- // make these arguments indirect then they'd be immediates
- // in LLVM, which means that they'd used whatever the
- // appropriate ABI is for the callee and the caller. That
- // means, for example, if the caller doesn't have AVX
- // enabled but the callee does, then passing an AVX argument
- // across this boundary would cause corrupt data to show up.
- //
- // This problem is fixed by unconditionally passing SIMD
- // arguments through memory between callers and callees
- // which should get them all to agree on ABI regardless of
- // target feature sets. Some more information about this
- // issue can be found in #44367.
- //
- // Note that the platform intrinsic ABI is exempt here as
- // that's how we connect up to LLVM and it's unstable
- // anyway, we control all calls to it in libstd.
- layout::Abi::Vector { .. }
- if abi != Abi::PlatformIntrinsic &&
- cx.sess().target.target.options.simd_types_indirect =>
- {
- arg.make_indirect();
- return
- }
-
- _ => return
- }
-
- let size = arg.layout.size;
- if arg.layout.is_unsized() || 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;
- }
-
- if let Err(msg) = self.adjust_for_cabi(cx, abi) {
- cx.sess().fatal(&msg);
- }
- }
-
+impl<'tcx> FnTypeLlvmExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
fn llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type {
let args_capacity: usize = self.args.iter().map(|arg|
if arg.pad.is_some() { 1 } else { 0 } +
}
}
-impl AbiMethods<'tcx> for CodegenCx<'ll, 'tcx> {
- fn new_fn_type(&self, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> FnType<'tcx, Ty<'tcx>> {
- FnType::new(&self, sig, extra_args)
- }
- fn new_vtable(
- &self,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>]
- ) -> FnType<'tcx, Ty<'tcx>> {
- FnType::new_vtable(&self, sig, extra_args)
- }
- fn fn_type_of_instance(&self, instance: &Instance<'tcx>) -> FnType<'tcx, Ty<'tcx>> {
- FnType::of_instance(&self, instance)
- }
-}
-
impl AbiBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
fn apply_attrs_callsite(
&mut self,
projects / rust.git / blobdiff