blob: 8821fb21fd00242abb39df0035d031d15f75765b [file] [log] [blame]
use super::operand::{OperandRef, OperandValue};
use super::place::PlaceRef;
use super::FunctionCx;
use crate::common::IntPredicate;
use crate::errors;
use crate::errors::InvalidMonomorphization;
use crate::glue;
use crate::meth;
use crate::traits::*;
use crate::MemFlags;
use rustc_middle::ty::{self, Ty, TyCtxt};
use rustc_span::{sym, Span};
use rustc_target::abi::{
call::{FnAbi, PassMode},
WrappingRange,
};
fn copy_intrinsic<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
bx: &mut Bx,
allow_overlap: bool,
volatile: bool,
ty: Ty<'tcx>,
dst: Bx::Value,
src: Bx::Value,
count: Bx::Value,
) {
let layout = bx.layout_of(ty);
let size = layout.size;
let align = layout.align.abi;
let size = bx.mul(bx.const_usize(size.bytes()), count);
let flags = if volatile { MemFlags::VOLATILE } else { MemFlags::empty() };
if allow_overlap {
bx.memmove(dst, align, src, align, size, flags);
} else {
bx.memcpy(dst, align, src, align, size, flags);
}
}
fn memset_intrinsic<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
bx: &mut Bx,
volatile: bool,
ty: Ty<'tcx>,
dst: Bx::Value,
val: Bx::Value,
count: Bx::Value,
) {
let layout = bx.layout_of(ty);
let size = layout.size;
let align = layout.align.abi;
let size = bx.mul(bx.const_usize(size.bytes()), count);
let flags = if volatile { MemFlags::VOLATILE } else { MemFlags::empty() };
bx.memset(dst, val, size, align, flags);
}
impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
pub fn codegen_intrinsic_call(
bx: &mut Bx,
instance: ty::Instance<'tcx>,
fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
args: &[OperandRef<'tcx, Bx::Value>],
llresult: Bx::Value,
span: Span,
) {
let callee_ty = instance.ty(bx.tcx(), ty::ParamEnv::reveal_all());
let ty::FnDef(def_id, fn_args) = *callee_ty.kind() else {
bug!("expected fn item type, found {}", callee_ty);
};
let sig = callee_ty.fn_sig(bx.tcx());
let sig = bx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig);
let arg_tys = sig.inputs();
let ret_ty = sig.output();
let name = bx.tcx().item_name(def_id);
let name_str = name.as_str();
let llret_ty = bx.backend_type(bx.layout_of(ret_ty));
let result = PlaceRef::new_sized(llresult, fn_abi.ret.layout);
let llval = match name {
sym::abort => {
bx.abort();
return;
}
sym::va_start => bx.va_start(args[0].immediate()),
sym::va_end => bx.va_end(args[0].immediate()),
sym::size_of_val => {
let tp_ty = fn_args.type_at(0);
if let OperandValue::Pair(_, meta) = args[0].val {
let (llsize, _) = glue::size_and_align_of_dst(bx, tp_ty, Some(meta));
llsize
} else {
bx.const_usize(bx.layout_of(tp_ty).size.bytes())
}
}
sym::min_align_of_val => {
let tp_ty = fn_args.type_at(0);
if let OperandValue::Pair(_, meta) = args[0].val {
let (_, llalign) = glue::size_and_align_of_dst(bx, tp_ty, Some(meta));
llalign
} else {
bx.const_usize(bx.layout_of(tp_ty).align.abi.bytes())
}
}
sym::vtable_size | sym::vtable_align => {
let vtable = args[0].immediate();
let idx = match name {
sym::vtable_size => ty::COMMON_VTABLE_ENTRIES_SIZE,
sym::vtable_align => ty::COMMON_VTABLE_ENTRIES_ALIGN,
_ => bug!(),
};
let value = meth::VirtualIndex::from_index(idx).get_usize(bx, vtable);
match name {
// Size is always <= isize::MAX.
sym::vtable_size => {
let size_bound = bx.data_layout().ptr_sized_integer().signed_max() as u128;
bx.range_metadata(value, WrappingRange { start: 0, end: size_bound });
},
// Alignment is always nonzero.
sym::vtable_align => bx.range_metadata(value, WrappingRange { start: 1, end: !0 }),
_ => {}
}
value
}
sym::pref_align_of
| sym::needs_drop
| sym::type_id
| sym::type_name
| sym::variant_count => {
let value = bx
.tcx()
.const_eval_instance(ty::ParamEnv::reveal_all(), instance, None)
.unwrap();
OperandRef::from_const(bx, value, ret_ty).immediate_or_packed_pair(bx)
}
sym::arith_offset => {
let ty = fn_args.type_at(0);
let layout = bx.layout_of(ty);
let ptr = args[0].immediate();
let offset = args[1].immediate();
bx.gep(bx.backend_type(layout), ptr, &[offset])
}
sym::copy => {
copy_intrinsic(
bx,
true,
false,
fn_args.type_at(0),
args[1].immediate(),
args[0].immediate(),
args[2].immediate(),
);
return;
}
sym::write_bytes => {
memset_intrinsic(
bx,
false,
fn_args.type_at(0),
args[0].immediate(),
args[1].immediate(),
args[2].immediate(),
);
return;
}
sym::volatile_copy_nonoverlapping_memory => {
copy_intrinsic(
bx,
false,
true,
fn_args.type_at(0),
args[0].immediate(),
args[1].immediate(),
args[2].immediate(),
);
return;
}
sym::volatile_copy_memory => {
copy_intrinsic(
bx,
true,
true,
fn_args.type_at(0),
args[0].immediate(),
args[1].immediate(),
args[2].immediate(),
);
return;
}
sym::volatile_set_memory => {
memset_intrinsic(
bx,
true,
fn_args.type_at(0),
args[0].immediate(),
args[1].immediate(),
args[2].immediate(),
);
return;
}
sym::volatile_store => {
let dst = args[0].deref(bx.cx());
args[1].val.volatile_store(bx, dst);
return;
}
sym::unaligned_volatile_store => {
let dst = args[0].deref(bx.cx());
args[1].val.unaligned_volatile_store(bx, dst);
return;
}
sym::exact_div => {
let ty = arg_tys[0];
match int_type_width_signed(ty, bx.tcx()) {
Some((_width, signed)) => {
if signed {
bx.exactsdiv(args[0].immediate(), args[1].immediate())
} else {
bx.exactudiv(args[0].immediate(), args[1].immediate())
}
},
None => {
bx.tcx().sess.emit_err(InvalidMonomorphization::BasicIntegerType { span, name, ty });
return;
}
}
}
sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => {
match float_type_width(arg_tys[0]) {
Some(_width) => match name {
sym::fadd_fast => bx.fadd_fast(args[0].immediate(), args[1].immediate()),
sym::fsub_fast => bx.fsub_fast(args[0].immediate(), args[1].immediate()),
sym::fmul_fast => bx.fmul_fast(args[0].immediate(), args[1].immediate()),
sym::fdiv_fast => bx.fdiv_fast(args[0].immediate(), args[1].immediate()),
sym::frem_fast => bx.frem_fast(args[0].immediate(), args[1].immediate()),
_ => bug!(),
},
None => {
bx.tcx().sess.emit_err(InvalidMonomorphization::BasicFloatType { span, name, ty: arg_tys[0] });
return;
}
}
}
sym::float_to_int_unchecked => {
if float_type_width(arg_tys[0]).is_none() {
bx.tcx().sess.emit_err(InvalidMonomorphization::FloatToIntUnchecked { span, ty: arg_tys[0] });
return;
}
let Some((_width, signed)) = int_type_width_signed(ret_ty, bx.tcx()) else {
bx.tcx().sess.emit_err(InvalidMonomorphization::FloatToIntUnchecked { span, ty: ret_ty });
return;
};
if signed {
bx.fptosi(args[0].immediate(), llret_ty)
} else {
bx.fptoui(args[0].immediate(), llret_ty)
}
}
sym::discriminant_value => {
if ret_ty.is_integral() {
args[0].deref(bx.cx()).codegen_get_discr(bx, ret_ty)
} else {
span_bug!(span, "Invalid discriminant type for `{:?}`", arg_tys[0])
}
}
sym::const_allocate => {
// returns a null pointer at runtime.
bx.const_null(bx.type_ptr())
}
sym::const_deallocate => {
// nop at runtime.
return;
}
// This requires that atomic intrinsics follow a specific naming pattern:
// "atomic_<operation>[_<ordering>]"
name if let Some(atomic) = name_str.strip_prefix("atomic_") => {
use crate::common::AtomicOrdering::*;
use crate::common::{AtomicRmwBinOp, SynchronizationScope};
let Some((instruction, ordering)) = atomic.split_once('_') else {
bx.sess().emit_fatal(errors::MissingMemoryOrdering);
};
let parse_ordering = |bx: &Bx, s| match s {
"unordered" => Unordered,
"relaxed" => Relaxed,
"acquire" => Acquire,
"release" => Release,
"acqrel" => AcquireRelease,
"seqcst" => SequentiallyConsistent,
_ => bx.sess().emit_fatal(errors::UnknownAtomicOrdering),
};
let invalid_monomorphization = |ty| {
bx.tcx().sess.emit_err(InvalidMonomorphization::BasicIntegerType { span, name, ty });
};
match instruction {
"cxchg" | "cxchgweak" => {
let Some((success, failure)) = ordering.split_once('_') else {
bx.sess().emit_fatal(errors::AtomicCompareExchange);
};
let ty = fn_args.type_at(0);
if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
let weak = instruction == "cxchgweak";
let dst = args[0].immediate();
let mut cmp = args[1].immediate();
let mut src = args[2].immediate();
if ty.is_unsafe_ptr() {
// Some platforms do not support atomic operations on pointers,
// so we cast to integer first.
cmp = bx.ptrtoint(cmp, bx.type_isize());
src = bx.ptrtoint(src, bx.type_isize());
}
let pair = bx.atomic_cmpxchg(dst, cmp, src, parse_ordering(bx, success), parse_ordering(bx, failure), weak);
let val = bx.extract_value(pair, 0);
let success = bx.extract_value(pair, 1);
let val = bx.from_immediate(val);
let success = bx.from_immediate(success);
let dest = result.project_field(bx, 0);
bx.store(val, dest.llval, dest.align);
let dest = result.project_field(bx, 1);
bx.store(success, dest.llval, dest.align);
return;
} else {
return invalid_monomorphization(ty);
}
}
"load" => {
let ty = fn_args.type_at(0);
if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
let layout = bx.layout_of(ty);
let size = layout.size;
let source = args[0].immediate();
if ty.is_unsafe_ptr() {
// Some platforms do not support atomic operations on pointers,
// so we cast to integer first...
let llty = bx.type_isize();
let result = bx.atomic_load(llty, source, parse_ordering(bx, ordering), size);
// ... and then cast the result back to a pointer
bx.inttoptr(result, bx.backend_type(layout))
} else {
bx.atomic_load(bx.backend_type(layout), source, parse_ordering(bx, ordering), size)
}
} else {
return invalid_monomorphization(ty);
}
}
"store" => {
let ty = fn_args.type_at(0);
if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
let size = bx.layout_of(ty).size;
let mut val = args[1].immediate();
let ptr = args[0].immediate();
if ty.is_unsafe_ptr() {
// Some platforms do not support atomic operations on pointers,
// so we cast to integer first.
val = bx.ptrtoint(val, bx.type_isize());
}
bx.atomic_store(val, ptr, parse_ordering(bx, ordering), size);
return;
} else {
return invalid_monomorphization(ty);
}
}
"fence" => {
bx.atomic_fence(parse_ordering(bx, ordering), SynchronizationScope::CrossThread);
return;
}
"singlethreadfence" => {
bx.atomic_fence(parse_ordering(bx, ordering), SynchronizationScope::SingleThread);
return;
}
// These are all AtomicRMW ops
op => {
let atom_op = match op {
"xchg" => AtomicRmwBinOp::AtomicXchg,
"xadd" => AtomicRmwBinOp::AtomicAdd,
"xsub" => AtomicRmwBinOp::AtomicSub,
"and" => AtomicRmwBinOp::AtomicAnd,
"nand" => AtomicRmwBinOp::AtomicNand,
"or" => AtomicRmwBinOp::AtomicOr,
"xor" => AtomicRmwBinOp::AtomicXor,
"max" => AtomicRmwBinOp::AtomicMax,
"min" => AtomicRmwBinOp::AtomicMin,
"umax" => AtomicRmwBinOp::AtomicUMax,
"umin" => AtomicRmwBinOp::AtomicUMin,
_ => bx.sess().emit_fatal(errors::UnknownAtomicOperation),
};
let ty = fn_args.type_at(0);
if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
let ptr = args[0].immediate();
let mut val = args[1].immediate();
if ty.is_unsafe_ptr() {
// Some platforms do not support atomic operations on pointers,
// so we cast to integer first.
val = bx.ptrtoint(val, bx.type_isize());
}
bx.atomic_rmw(atom_op, ptr, val, parse_ordering(bx, ordering))
} else {
return invalid_monomorphization(ty);
}
}
}
}
sym::nontemporal_store => {
let dst = args[0].deref(bx.cx());
args[1].val.nontemporal_store(bx, dst);
return;
}
sym::ptr_guaranteed_cmp => {
let a = args[0].immediate();
let b = args[1].immediate();
bx.icmp(IntPredicate::IntEQ, a, b)
}
sym::ptr_offset_from | sym::ptr_offset_from_unsigned => {
let ty = fn_args.type_at(0);
let pointee_size = bx.layout_of(ty).size;
let a = args[0].immediate();
let b = args[1].immediate();
let a = bx.ptrtoint(a, bx.type_isize());
let b = bx.ptrtoint(b, bx.type_isize());
let pointee_size = bx.const_usize(pointee_size.bytes());
if name == sym::ptr_offset_from {
// This is the same sequence that Clang emits for pointer subtraction.
// It can be neither `nsw` nor `nuw` because the input is treated as
// unsigned but then the output is treated as signed, so neither works.
let d = bx.sub(a, b);
// this is where the signed magic happens (notice the `s` in `exactsdiv`)
bx.exactsdiv(d, pointee_size)
} else {
// The `_unsigned` version knows the relative ordering of the pointers,
// so can use `sub nuw` and `udiv exact` instead of dealing in signed.
let d = bx.unchecked_usub(a, b);
bx.exactudiv(d, pointee_size)
}
}
_ => {
// Need to use backend-specific things in the implementation.
bx.codegen_intrinsic_call(instance, fn_abi, args, llresult, span);
return;
}
};
if !fn_abi.ret.is_ignore() {
if let PassMode::Cast(..) = &fn_abi.ret.mode {
bx.store(llval, result.llval, result.align);
} else {
OperandRef::from_immediate_or_packed_pair(bx, llval, result.layout)
.val
.store(bx, result);
}
}
}
}
// Returns the width of an int Ty, and if it's signed or not
// Returns None if the type is not an integer
// FIXME: there’s multiple of this functions, investigate using some of the already existing
// stuffs.
fn int_type_width_signed(ty: Ty<'_>, tcx: TyCtxt<'_>) -> Option<(u64, bool)> {
match ty.kind() {
ty::Int(t) => {
Some((t.bit_width().unwrap_or(u64::from(tcx.sess.target.pointer_width)), true))
}
ty::Uint(t) => {
Some((t.bit_width().unwrap_or(u64::from(tcx.sess.target.pointer_width)), false))
}
_ => None,
}
}
// Returns the width of a float Ty
// Returns None if the type is not a float
fn float_type_width(ty: Ty<'_>) -> Option<u64> {
match ty.kind() {
ty::Float(t) => Some(t.bit_width()),
_ => None,
}
}