StableHasherResult};
pub use rustc_target::abi::*;
-use rustc_target::spec::HasTargetSpec;
+use rustc_target::spec::{HasTargetSpec, abi::Abi as SpecAbi};
use rustc_target::abi::call::{
- ArgAttribute, ArgAttributes, ArgType, Conv, FnType, IgnoreMode, PassMode
+ ArgAttribute, ArgAttributes, ArgType, Conv, FnType, IgnoreMode, PassMode, Reg, RegKind
};
}
}
-pub trait FnTypeExt<'tcx, C> {
- fn of_instance(cx: &C, instance: &ty::Instance<'tcx>) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>;
- fn new(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>;
- fn new_vtable(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>;
+pub trait FnTypeExt<'tcx, C>
+where
+ C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
+ + HasDataLayout
+ + HasTargetSpec
+ + HasTyCtxt<'tcx>
+ + HasParamEnv<'tcx>,
+{
+ fn of_instance(cx: &C, instance: &ty::Instance<'tcx>) -> Self;
+ fn new(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self;
+ fn new_vtable(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self;
fn new_internal(
cx: &C,
sig: ty::FnSig<'tcx>,
extra_args: &[Ty<'tcx>],
mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
- ) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>;
+ ) -> Self;
+ fn adjust_for_abi(&mut self, cx: &C, abi: SpecAbi);
}
-
-impl<'tcx, C> FnTypeExt<'tcx, C> for call::FnType<'tcx, Ty<'tcx>> {
- fn of_instance(cx: &C, instance: &ty::Instance<'tcx>) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>,
- {
+impl<'tcx, C> FnTypeExt<'tcx, C> for call::FnType<'tcx, Ty<'tcx>>
+where
+ C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
+ + HasDataLayout
+ + HasTargetSpec
+ + HasTyCtxt<'tcx>
+ + HasParamEnv<'tcx>,
+{
+ fn of_instance(cx: &C, instance: &ty::Instance<'tcx>) -> Self {
let sig = instance.fn_sig(cx.tcx());
let sig = cx
.tcx()
call::FnType::new(cx, sig, &[])
}
- fn new(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>,
- {
+ fn new(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self {
call::FnType::new_internal(cx, sig, extra_args, |ty, _| ArgType::new(cx.layout_of(ty)))
}
-
- fn new_vtable(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>,
- {
- FnType::new_internal(cx, sig, extra_args, |ty, arg_idx| {
+ fn new_vtable(cx: &C, sig: ty::FnSig<'tcx>, extra_args: &[Ty<'tcx>]) -> Self {
+ FnTypeExt::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`
}
fn new_internal(
- cx: &C,
- sig: ty::FnSig<'tcx>,
- extra_args: &[Ty<'tcx>],
- mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
- ) -> Self
- where
- C: LayoutOf<Ty = Ty<'tcx>, TyLayout = TyLayout<'tcx>>
- + HasDataLayout
- + HasTargetSpec
- + HasTargetSpec
- + HasTyCtxt<'tcx>
- + HasParamEnv<'tcx>,
- {
+ cx: &C,
+ 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 rustc_target::spec::abi::Abi::*;
arg
};
- let fn_ty = FnType {
+ let mut fn_ty = FnType {
ret: arg_of(sig.output(), None),
args: inputs
.iter()
c_variadic: sig.c_variadic,
conv,
};
- // FIXME: uncomment this after figuring out wwhere should adjust_for_abi reside.
- //fn_ty.adjust_for_abi(cx, sig.abi);
+ fn_ty.adjust_for_abi(cx, sig.abi);
fn_ty
}
+
+ fn adjust_for_abi(&mut self, cx: &C, abi: SpecAbi) {
+ if abi == SpecAbi::Unadjusted {
+ return;
+ }
+
+ if abi == SpecAbi::Rust
+ || abi == SpecAbi::RustCall
+ || abi == SpecAbi::RustIntrinsic
+ || abi == SpecAbi::PlatformIntrinsic
+ {
+ let fixup = |arg: &mut ArgType<'tcx, Ty<'tcx>>| {
+ if arg.is_ignore() {
+ return;
+ }
+
+ match arg.layout.abi {
+ 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.
+ Abi::Vector { .. }
+ if abi != SpecAbi::PlatformIntrinsic
+ && cx.tcx().sess.target.target.options.simd_types_indirect =>
+ {
+ arg.make_indirect();
+ return;
+ }
+
+ _ => return,
+ }
+
+ let size = arg.layout.size;
+ if arg.layout.is_unsized() || size > 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.tcx().sess.fatal(&msg);
+ }
+ }
}
}
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);
}
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);
+ FnTypeExt::new(cx, sig, &[])
+ }
+
+ fn new(cx: &CodegenCx<'ll, 'tcx>,
+ sig: ty::FnSig<'tcx>,
+ extra_args: &[Ty<'tcx>]) -> Self {
+ FnTypeExt::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 {
+ FnTypeExt::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,
+ };
+ FnTypeExt::adjust_for_abi(&mut fn_ty, cx, sig.abi);
+ fn_ty
+ }
+
fn adjust_for_abi(&mut self,
cx: &CodegenCx<'ll, 'tcx>,
abi: Abi) {
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)
+ FnTypeExt::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)
+ FnTypeExt::new_vtable(&self, sig, extra_args)
}
fn fn_type_of_instance(&self, instance: &Instance<'tcx>) -> FnType<'tcx, Ty<'tcx>> {
- FnType::of_instance(&self, instance)
+ FnTypeExt::of_instance(&self, instance)
}
}
projects / rust.git / commitdiff