863 lines
34 KiB
Rust
863 lines
34 KiB
Rust
use crate::llvm::{self, AttributePlace};
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use crate::builder::Builder;
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use crate::context::CodegenCx;
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use crate::type_::Type;
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use crate::type_of::{LayoutLlvmExt, PointerKind};
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use crate::value::Value;
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use rustc_codegen_ssa::MemFlags;
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use rustc_codegen_ssa::mir::place::PlaceRef;
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use rustc_codegen_ssa::mir::operand::OperandValue;
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use rustc_target::abi::call::ArgType;
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use rustc_codegen_ssa::traits::*;
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use rustc_target::abi::{HasDataLayout, LayoutOf, Size, TyLayout, Abi as LayoutAbi};
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use rustc::ty::{self, Ty, Instance};
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use rustc::ty::layout;
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use libc::c_uint;
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pub use rustc_target::spec::abi::Abi;
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pub use rustc::ty::layout::{FAT_PTR_ADDR, FAT_PTR_EXTRA};
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pub use rustc_target::abi::call::*;
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macro_rules! for_each_kind {
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($flags: ident, $f: ident, $($kind: ident),+) => ({
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$(if $flags.contains(ArgAttribute::$kind) { $f(llvm::Attribute::$kind) })+
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})
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}
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trait ArgAttributeExt {
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fn for_each_kind<F>(&self, f: F) where F: FnMut(llvm::Attribute);
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}
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impl ArgAttributeExt for ArgAttribute {
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fn for_each_kind<F>(&self, mut f: F) where F: FnMut(llvm::Attribute) {
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for_each_kind!(self, f,
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ByVal, NoAlias, NoCapture, NonNull, ReadOnly, SExt, StructRet, ZExt, InReg)
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}
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}
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pub trait ArgAttributesExt {
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fn apply_llfn(&self, idx: AttributePlace, llfn: &Value);
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fn apply_callsite(&self, idx: AttributePlace, callsite: &Value);
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}
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impl ArgAttributesExt for ArgAttributes {
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fn apply_llfn(&self, idx: AttributePlace, llfn: &Value) {
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let mut regular = self.regular;
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unsafe {
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let deref = self.pointee_size.bytes();
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if deref != 0 {
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if regular.contains(ArgAttribute::NonNull) {
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llvm::LLVMRustAddDereferenceableAttr(llfn,
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idx.as_uint(),
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deref);
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} else {
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llvm::LLVMRustAddDereferenceableOrNullAttr(llfn,
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idx.as_uint(),
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deref);
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}
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regular -= ArgAttribute::NonNull;
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}
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if let Some(align) = self.pointee_align {
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llvm::LLVMRustAddAlignmentAttr(llfn,
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idx.as_uint(),
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align.bytes() as u32);
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}
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regular.for_each_kind(|attr| attr.apply_llfn(idx, llfn));
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}
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}
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fn apply_callsite(&self, idx: AttributePlace, callsite: &Value) {
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let mut regular = self.regular;
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unsafe {
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let deref = self.pointee_size.bytes();
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if deref != 0 {
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if regular.contains(ArgAttribute::NonNull) {
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llvm::LLVMRustAddDereferenceableCallSiteAttr(callsite,
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idx.as_uint(),
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deref);
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} else {
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llvm::LLVMRustAddDereferenceableOrNullCallSiteAttr(callsite,
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idx.as_uint(),
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deref);
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}
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regular -= ArgAttribute::NonNull;
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}
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if let Some(align) = self.pointee_align {
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llvm::LLVMRustAddAlignmentCallSiteAttr(callsite,
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idx.as_uint(),
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align.bytes() as u32);
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}
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regular.for_each_kind(|attr| attr.apply_callsite(idx, callsite));
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}
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}
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}
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pub trait LlvmType {
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fn llvm_type(&self, cx: &CodegenCx<'ll, '_>) -> &'ll Type;
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}
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impl LlvmType for Reg {
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fn llvm_type(&self, cx: &CodegenCx<'ll, '_>) -> &'ll Type {
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match self.kind {
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RegKind::Integer => cx.type_ix(self.size.bits()),
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RegKind::Float => {
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match self.size.bits() {
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32 => cx.type_f32(),
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64 => cx.type_f64(),
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_ => bug!("unsupported float: {:?}", self)
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}
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}
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RegKind::Vector => {
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cx.type_vector(cx.type_i8(), self.size.bytes())
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}
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}
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}
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}
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impl LlvmType for CastTarget {
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fn llvm_type(&self, cx: &CodegenCx<'ll, '_>) -> &'ll Type {
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let rest_ll_unit = self.rest.unit.llvm_type(cx);
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let (rest_count, rem_bytes) = if self.rest.unit.size.bytes() == 0 {
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(0, 0)
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} else {
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(self.rest.total.bytes() / self.rest.unit.size.bytes(),
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self.rest.total.bytes() % self.rest.unit.size.bytes())
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};
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if self.prefix.iter().all(|x| x.is_none()) {
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// Simplify to a single unit when there is no prefix and size <= unit size
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if self.rest.total <= self.rest.unit.size {
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return rest_ll_unit;
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}
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// Simplify to array when all chunks are the same size and type
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if rem_bytes == 0 {
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return cx.type_array(rest_ll_unit, rest_count);
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}
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}
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// Create list of fields in the main structure
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let mut args: Vec<_> =
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self.prefix.iter().flat_map(|option_kind| option_kind.map(
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|kind| Reg { kind: kind, size: self.prefix_chunk }.llvm_type(cx)))
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.chain((0..rest_count).map(|_| rest_ll_unit))
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.collect();
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// Append final integer
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if rem_bytes != 0 {
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// Only integers can be really split further.
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assert_eq!(self.rest.unit.kind, RegKind::Integer);
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args.push(cx.type_ix(rem_bytes * 8));
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}
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cx.type_struct(&args, false)
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}
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}
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pub trait ArgTypeExt<'ll, 'tcx> {
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fn memory_ty(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
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fn store(
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&self,
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bx: &mut Builder<'_, 'll, 'tcx>,
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val: &'ll Value,
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dst: PlaceRef<'tcx, &'ll Value>,
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);
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fn store_fn_arg(
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&self,
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bx: &mut Builder<'_, 'll, 'tcx>,
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idx: &mut usize,
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dst: PlaceRef<'tcx, &'ll Value>,
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);
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}
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impl ArgTypeExt<'ll, 'tcx> for ArgType<'tcx, Ty<'tcx>> {
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/// Gets the LLVM type for a place of the original Rust type of
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/// this argument/return, i.e., the result of `type_of::type_of`.
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fn memory_ty(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type {
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self.layout.llvm_type(cx)
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}
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/// Stores a direct/indirect value described by this ArgType into a
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/// place for the original Rust type of this argument/return.
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/// Can be used for both storing formal arguments into Rust variables
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/// or results of call/invoke instructions into their destinations.
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fn store(
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&self,
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bx: &mut Builder<'_, 'll, 'tcx>,
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val: &'ll Value,
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dst: PlaceRef<'tcx, &'ll Value>,
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) {
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if self.is_ignore() {
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return;
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}
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if self.is_sized_indirect() {
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OperandValue::Ref(val, None, self.layout.align.abi).store(bx, dst)
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} else if self.is_unsized_indirect() {
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bug!("unsized ArgType must be handled through store_fn_arg");
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} else if let PassMode::Cast(cast) = self.mode {
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// FIXME(eddyb): Figure out when the simpler Store is safe, clang
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// uses it for i16 -> {i8, i8}, but not for i24 -> {i8, i8, i8}.
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let can_store_through_cast_ptr = false;
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if can_store_through_cast_ptr {
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let cast_ptr_llty = bx.type_ptr_to(cast.llvm_type(bx));
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let cast_dst = bx.pointercast(dst.llval, cast_ptr_llty);
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bx.store(val, cast_dst, self.layout.align.abi);
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} else {
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// The actual return type is a struct, but the ABI
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// adaptation code has cast it into some scalar type. The
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// code that follows is the only reliable way I have
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// found to do a transform like i64 -> {i32,i32}.
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// Basically we dump the data onto the stack then memcpy it.
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//
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// Other approaches I tried:
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// - Casting rust ret pointer to the foreign type and using Store
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// is (a) unsafe if size of foreign type > size of rust type and
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// (b) runs afoul of strict aliasing rules, yielding invalid
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// assembly under -O (specifically, the store gets removed).
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// - Truncating foreign type to correct integral type and then
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// bitcasting to the struct type yields invalid cast errors.
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// We instead thus allocate some scratch space...
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let scratch_size = cast.size(bx);
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let scratch_align = cast.align(bx);
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let llscratch = bx.alloca(cast.llvm_type(bx), "abi_cast", scratch_align);
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bx.lifetime_start(llscratch, scratch_size);
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// ...where we first store the value...
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bx.store(val, llscratch, scratch_align);
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// ...and then memcpy it to the intended destination.
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bx.memcpy(
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dst.llval,
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self.layout.align.abi,
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llscratch,
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scratch_align,
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bx.const_usize(self.layout.size.bytes()),
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MemFlags::empty()
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);
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bx.lifetime_end(llscratch, scratch_size);
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}
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} else {
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OperandValue::Immediate(val).store(bx, dst);
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}
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}
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fn store_fn_arg(
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&self,
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bx: &mut Builder<'a, 'll, 'tcx>,
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idx: &mut usize,
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dst: PlaceRef<'tcx, &'ll Value>,
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) {
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let mut next = || {
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let val = llvm::get_param(bx.llfn(), *idx as c_uint);
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*idx += 1;
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val
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};
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match self.mode {
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PassMode::Ignore(_) => {}
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PassMode::Pair(..) => {
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OperandValue::Pair(next(), next()).store(bx, dst);
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}
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PassMode::Indirect(_, Some(_)) => {
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OperandValue::Ref(next(), Some(next()), self.layout.align.abi).store(bx, dst);
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}
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PassMode::Direct(_) | PassMode::Indirect(_, None) | PassMode::Cast(_) => {
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self.store(bx, next(), dst);
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}
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}
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}
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}
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impl ArgTypeMethods<'tcx> for Builder<'a, 'll, 'tcx> {
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fn store_fn_arg(
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&mut self,
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ty: &ArgType<'tcx, Ty<'tcx>>,
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idx: &mut usize, dst: PlaceRef<'tcx, Self::Value>
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) {
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ty.store_fn_arg(self, idx, dst)
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}
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fn store_arg_ty(
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&mut self,
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ty: &ArgType<'tcx, Ty<'tcx>>,
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val: &'ll Value,
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dst: PlaceRef<'tcx, &'ll Value>
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) {
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ty.store(self, val, dst)
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}
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fn memory_ty(&self, ty: &ArgType<'tcx, Ty<'tcx>>) -> &'ll Type {
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ty.memory_ty(self)
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}
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}
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pub trait FnTypeExt<'tcx> {
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fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>) -> Self;
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fn new(cx: &CodegenCx<'ll, 'tcx>,
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sig: ty::FnSig<'tcx>,
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extra_args: &[Ty<'tcx>]) -> Self;
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fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
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sig: ty::FnSig<'tcx>,
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extra_args: &[Ty<'tcx>]) -> Self;
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fn new_internal(
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cx: &CodegenCx<'ll, 'tcx>,
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sig: ty::FnSig<'tcx>,
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extra_args: &[Ty<'tcx>],
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mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
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) -> Self;
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fn adjust_for_abi(&mut self,
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cx: &CodegenCx<'ll, 'tcx>,
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abi: Abi);
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fn llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
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fn ptr_to_llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
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fn llvm_cconv(&self) -> llvm::CallConv;
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fn apply_attrs_llfn(&self, llfn: &'ll Value);
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fn apply_attrs_callsite(&self, bx: &mut Builder<'a, 'll, 'tcx>, callsite: &'ll Value);
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}
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impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
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fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>) -> Self {
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let sig = instance.fn_sig(cx.tcx);
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let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
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FnType::new(cx, sig, &[])
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}
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fn new(cx: &CodegenCx<'ll, 'tcx>,
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sig: ty::FnSig<'tcx>,
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extra_args: &[Ty<'tcx>]) -> Self {
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FnType::new_internal(cx, sig, extra_args, |ty, _| {
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ArgType::new(cx.layout_of(ty))
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})
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}
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fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
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sig: ty::FnSig<'tcx>,
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extra_args: &[Ty<'tcx>]) -> Self {
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FnType::new_internal(cx, sig, extra_args, |ty, arg_idx| {
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let mut layout = cx.layout_of(ty);
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// Don't pass the vtable, it's not an argument of the virtual fn.
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// Instead, pass just the data pointer, but give it the type `*const/mut dyn Trait`
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// or `&/&mut dyn Trait` because this is special-cased elsewhere in codegen
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if arg_idx == Some(0) {
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let fat_pointer_ty = if layout.is_unsized() {
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// unsized `self` is passed as a pointer to `self`
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// FIXME (mikeyhew) change this to use &own if it is ever added to the language
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cx.tcx.mk_mut_ptr(layout.ty)
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} else {
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match layout.abi {
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LayoutAbi::ScalarPair(..) => (),
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_ => bug!("receiver type has unsupported layout: {:?}", layout)
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}
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// In the case of Rc<Self>, we need to explicitly pass a *mut RcBox<Self>
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// with a Scalar (not ScalarPair) ABI. This is a hack that is understood
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// elsewhere in the compiler as a method on a `dyn Trait`.
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// To get the type `*mut RcBox<Self>`, we just keep unwrapping newtypes until we
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// get a built-in pointer type
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let mut fat_pointer_layout = layout;
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'descend_newtypes: while !fat_pointer_layout.ty.is_unsafe_ptr()
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&& !fat_pointer_layout.ty.is_region_ptr()
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{
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'iter_fields: for i in 0..fat_pointer_layout.fields.count() {
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let field_layout = fat_pointer_layout.field(cx, i);
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if !field_layout.is_zst() {
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fat_pointer_layout = field_layout;
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continue 'descend_newtypes
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}
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}
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bug!("receiver has no non-zero-sized fields {:?}", fat_pointer_layout);
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}
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fat_pointer_layout.ty
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};
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// we now have a type like `*mut RcBox<dyn Trait>`
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// change its layout to that of `*mut ()`, a thin pointer, but keep the same type
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// this is understood as a special case elsewhere in the compiler
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let unit_pointer_ty = cx.tcx.mk_mut_ptr(cx.tcx.mk_unit());
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layout = cx.layout_of(unit_pointer_ty);
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layout.ty = fat_pointer_ty;
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}
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ArgType::new(layout)
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})
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}
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fn new_internal(
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cx: &CodegenCx<'ll, 'tcx>,
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sig: ty::FnSig<'tcx>,
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extra_args: &[Ty<'tcx>],
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mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
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) -> Self {
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debug!("FnType::new_internal({:?}, {:?})", sig, extra_args);
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use self::Abi::*;
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let conv = match cx.sess().target.target.adjust_abi(sig.abi) {
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RustIntrinsic | PlatformIntrinsic |
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Rust | RustCall => Conv::C,
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// It's the ABI's job to select this, not ours.
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System => bug!("system abi should be selected elsewhere"),
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Stdcall => Conv::X86Stdcall,
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Fastcall => Conv::X86Fastcall,
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Vectorcall => Conv::X86VectorCall,
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Thiscall => Conv::X86ThisCall,
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C => Conv::C,
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Unadjusted => Conv::C,
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Win64 => Conv::X86_64Win64,
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SysV64 => Conv::X86_64SysV,
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Aapcs => Conv::ArmAapcs,
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PtxKernel => Conv::PtxKernel,
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Msp430Interrupt => Conv::Msp430Intr,
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X86Interrupt => Conv::X86Intr,
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AmdGpuKernel => Conv::AmdGpuKernel,
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// These API constants ought to be more specific...
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Cdecl => Conv::C,
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};
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let mut inputs = sig.inputs();
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let extra_args = if sig.abi == RustCall {
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assert!(!sig.variadic && extra_args.is_empty());
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match sig.inputs().last().unwrap().sty {
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ty::Tuple(ref tupled_arguments) => {
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inputs = &sig.inputs()[0..sig.inputs().len() - 1];
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tupled_arguments
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}
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_ => {
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bug!("argument to function with \"rust-call\" ABI \
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is not a tuple");
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}
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}
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} else {
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assert!(sig.variadic || extra_args.is_empty());
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extra_args
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};
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let target = &cx.sess().target.target;
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let win_x64_gnu = target.target_os == "windows"
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&& target.arch == "x86_64"
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&& target.target_env == "gnu";
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let linux_s390x = target.target_os == "linux"
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&& target.arch == "s390x"
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&& target.target_env == "gnu";
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let linux_sparc64 = target.target_os == "linux"
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&& target.arch == "sparc64"
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&& target.target_env == "gnu";
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let rust_abi = match sig.abi {
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RustIntrinsic | PlatformIntrinsic | Rust | RustCall => true,
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_ => false
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};
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// Handle safe Rust thin and fat pointers.
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let adjust_for_rust_scalar = |attrs: &mut ArgAttributes,
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scalar: &layout::Scalar,
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layout: TyLayout<'tcx, Ty<'tcx>>,
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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.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().chain(extra_args).enumerate().map(|(i, ty)| {
|
|
arg_of(ty, Some(i))
|
|
}).collect(),
|
|
variadic: sig.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);
|
|
}
|
|
}
|
|
|
|
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 } +
|
|
if let PassMode::Pair(_, _) = arg.mode { 2 } else { 1 }
|
|
).sum();
|
|
let mut llargument_tys = Vec::with_capacity(
|
|
if let PassMode::Indirect(..) = self.ret.mode { 1 } else { 0 } + args_capacity
|
|
);
|
|
|
|
let llreturn_ty = match self.ret.mode {
|
|
PassMode::Ignore(IgnoreMode::Zst) => cx.type_void(),
|
|
PassMode::Ignore(IgnoreMode::CVarArgs) =>
|
|
bug!("`va_list` should never be a return type"),
|
|
PassMode::Direct(_) | PassMode::Pair(..) => {
|
|
self.ret.layout.immediate_llvm_type(cx)
|
|
}
|
|
PassMode::Cast(cast) => cast.llvm_type(cx),
|
|
PassMode::Indirect(..) => {
|
|
llargument_tys.push(cx.type_ptr_to(self.ret.memory_ty(cx)));
|
|
cx.type_void()
|
|
}
|
|
};
|
|
|
|
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, true));
|
|
llargument_tys.push(arg.layout.scalar_pair_element_llvm_type(cx, 1, true));
|
|
continue;
|
|
}
|
|
PassMode::Indirect(_, Some(_)) => {
|
|
let ptr_ty = cx.tcx.mk_mut_ptr(arg.layout.ty);
|
|
let ptr_layout = cx.layout_of(ptr_ty);
|
|
llargument_tys.push(ptr_layout.scalar_pair_element_llvm_type(cx, 0, true));
|
|
llargument_tys.push(ptr_layout.scalar_pair_element_llvm_type(cx, 1, true));
|
|
continue;
|
|
}
|
|
PassMode::Cast(cast) => cast.llvm_type(cx),
|
|
PassMode::Indirect(_, None) => cx.type_ptr_to(arg.memory_ty(cx)),
|
|
};
|
|
llargument_tys.push(llarg_ty);
|
|
}
|
|
|
|
if self.variadic {
|
|
cx.type_variadic_func(&llargument_tys, llreturn_ty)
|
|
} else {
|
|
cx.type_func(&llargument_tys, llreturn_ty)
|
|
}
|
|
}
|
|
|
|
fn ptr_to_llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type {
|
|
unsafe {
|
|
llvm::LLVMPointerType(self.llvm_type(cx),
|
|
cx.data_layout().instruction_address_space as c_uint)
|
|
}
|
|
}
|
|
|
|
fn llvm_cconv(&self) -> llvm::CallConv {
|
|
match self.conv {
|
|
Conv::C => llvm::CCallConv,
|
|
Conv::AmdGpuKernel => llvm::AmdGpuKernel,
|
|
Conv::ArmAapcs => llvm::ArmAapcsCallConv,
|
|
Conv::Msp430Intr => llvm::Msp430Intr,
|
|
Conv::PtxKernel => llvm::PtxKernel,
|
|
Conv::X86Fastcall => llvm::X86FastcallCallConv,
|
|
Conv::X86Intr => llvm::X86_Intr,
|
|
Conv::X86Stdcall => llvm::X86StdcallCallConv,
|
|
Conv::X86ThisCall => llvm::X86_ThisCall,
|
|
Conv::X86VectorCall => llvm::X86_VectorCall,
|
|
Conv::X86_64SysV => llvm::X86_64_SysV,
|
|
Conv::X86_64Win64 => llvm::X86_64_Win64,
|
|
}
|
|
}
|
|
|
|
fn apply_attrs_llfn(&self, llfn: &'ll Value) {
|
|
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, None) => apply(attrs),
|
|
PassMode::Indirect(ref attrs, Some(ref extra_attrs)) => {
|
|
apply(attrs);
|
|
apply(extra_attrs);
|
|
}
|
|
PassMode::Pair(ref a, ref b) => {
|
|
apply(a);
|
|
apply(b);
|
|
}
|
|
PassMode::Cast(_) => apply(&ArgAttributes::new()),
|
|
}
|
|
}
|
|
}
|
|
|
|
fn apply_attrs_callsite(&self, bx: &mut Builder<'a, 'll, 'tcx>, callsite: &'ll Value) {
|
|
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),
|
|
_ => {}
|
|
}
|
|
if let layout::Abi::Scalar(ref scalar) = self.ret.layout.abi {
|
|
// If the value is a boolean, the range is 0..2 and that ultimately
|
|
// become 0..0 when the type becomes i1, which would be rejected
|
|
// by the LLVM verifier.
|
|
if let layout::Int(..) = scalar.value {
|
|
if !scalar.is_bool() {
|
|
let range = scalar.valid_range_exclusive(bx);
|
|
if range.start != range.end {
|
|
bx.range_metadata(callsite, range);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
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, None) => apply(attrs),
|
|
PassMode::Indirect(ref attrs, Some(ref extra_attrs)) => {
|
|
apply(attrs);
|
|
apply(extra_attrs);
|
|
}
|
|
PassMode::Pair(ref a, ref b) => {
|
|
apply(a);
|
|
apply(b);
|
|
}
|
|
PassMode::Cast(_) => apply(&ArgAttributes::new()),
|
|
}
|
|
}
|
|
|
|
let cconv = self.llvm_cconv();
|
|
if cconv != llvm::CCallConv {
|
|
llvm::SetInstructionCallConv(callsite, cconv);
|
|
}
|
|
}
|
|
}
|
|
|
|
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,
|
|
ty: &FnType<'tcx, Ty<'tcx>>,
|
|
callsite: Self::Value
|
|
) {
|
|
ty.apply_attrs_callsite(self, callsite)
|
|
}
|
|
}
|