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use crate::abi::call::{ArgAbi, FnAbi, Reg};
use crate::abi::{Abi, Float, Primitive};
// Win64 ABI: https://docs.microsoft.com/en-us/cpp/build/parameter-passing
pub fn compute_abi_info<Ty>(fn_abi: &mut FnAbi<'_, Ty>) {
let fixup = |a: &mut ArgAbi<'_, Ty>| {
match a.layout.abi {
Abi::Uninhabited | Abi::Aggregate { sized: false } => {}
Abi::ScalarPair(..) | Abi::Aggregate { sized: true } => match a.layout.size.bits() {
8 => a.cast_to(Reg::i8()),
16 => a.cast_to(Reg::i16()),
32 => a.cast_to(Reg::i32()),
64 => a.cast_to(Reg::i64()),
_ => a.make_indirect(),
},
Abi::Vector { .. } => {
// FIXME(eddyb) there should be a size cap here
// (probably what clang calls "illegal vectors").
}
Abi::Scalar(scalar) => {
// Match what LLVM does for `f128` so that `compiler-builtins` builtins match up
// with what LLVM expects.
if a.layout.size.bytes() > 8
&& !matches!(scalar.primitive(), Primitive::Float(Float::F128))
{
a.make_indirect();
} else {
a.extend_integer_width_to(32);
}
}
}
};
if !fn_abi.ret.is_ignore() {
fixup(&mut fn_abi.ret);
}
for arg in fn_abi.args.iter_mut() {
if arg.is_ignore() {
continue;
}
fixup(arg);
}
}