rustc_target/callconv/
s390x.rs

1// Reference: ELF Application Binary Interface s390x Supplement
2// https://github.com/IBM/s390x-abi
3
4use rustc_abi::{BackendRepr, HasDataLayout, TyAbiInterface};
5
6use crate::callconv::{ArgAbi, FnAbi, Reg, RegKind};
7use crate::spec::{Env, HasTargetSpec, Os};
8
9fn classify_ret<Ty>(ret: &mut ArgAbi<'_, Ty>) {
10    let size = ret.layout.size;
11    if size.bits() <= 128 && matches!(ret.layout.backend_repr, BackendRepr::SimdVector { .. }) {
12        return;
13    }
14    if !ret.layout.is_aggregate() && size.bits() <= 64 {
15        ret.extend_integer_width_to(64);
16    } else {
17        ret.make_indirect();
18    }
19}
20
21fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>)
22where
23    Ty: TyAbiInterface<'a, C> + Copy,
24    C: HasDataLayout + HasTargetSpec,
25{
26    if !arg.layout.is_sized() {
27        // Not touching this...
28        return;
29    }
30    if arg.is_ignore() {
31        // s390x-unknown-linux-{gnu,musl,uclibc} doesn't ignore ZSTs.
32        if cx.target_spec().os == Os::Linux
33            && matches!(cx.target_spec().env, Env::Gnu | Env::Musl | Env::Uclibc)
34            && arg.layout.is_zst()
35        {
36            arg.make_indirect_from_ignore();
37        }
38        return;
39    }
40    if arg.layout.pass_indirectly_in_non_rustic_abis(cx) {
41        arg.make_indirect();
42        return;
43    }
44
45    let size = arg.layout.size;
46    if size.bits() <= 128 {
47        if let BackendRepr::SimdVector { .. } = arg.layout.backend_repr {
48            // pass non-wrapped vector types using `PassMode::Direct`
49            return;
50        }
51
52        if arg.layout.is_single_vector_element(cx, size) {
53            // pass non-transparent wrappers around a vector as `PassMode::Cast`
54            arg.cast_to(Reg { kind: RegKind::Vector, size });
55            return;
56        }
57    }
58    if !arg.layout.is_aggregate() && size.bits() <= 64 {
59        arg.extend_integer_width_to(64);
60        return;
61    }
62
63    if arg.layout.is_single_fp_element(cx) {
64        match size.bytes() {
65            4 => arg.cast_to(Reg::f32()),
66            8 => arg.cast_to(Reg::f64()),
67            _ => arg.make_indirect(),
68        }
69    } else {
70        match size.bytes() {
71            1 => arg.cast_to(Reg::i8()),
72            2 => arg.cast_to(Reg::i16()),
73            4 => arg.cast_to(Reg::i32()),
74            8 => arg.cast_to(Reg::i64()),
75            _ => arg.make_indirect(),
76        }
77    }
78}
79
80pub(crate) fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>)
81where
82    Ty: TyAbiInterface<'a, C> + Copy,
83    C: HasDataLayout + HasTargetSpec,
84{
85    if !fn_abi.ret.is_ignore() {
86        classify_ret(&mut fn_abi.ret);
87    }
88
89    for arg in fn_abi.args.iter_mut() {
90        classify_arg(cx, arg);
91    }
92}
rustc_target/callconv/s390x.rs

rustc_target/callconv/
s390x.rs
