src/librustc_target/abi/call/s390x.rs

   1 // FIXME: The assumes we're using the non-vector ABI, i.e., compiling
   2 // for a pre-z13 machine or using -mno-vx.
   3
   4 use crate::abi::call::{ArgAbi, FnAbi, Reg};
   5 use crate::abi::{self, HasDataLayout, LayoutOf, TyAndLayout, TyAndLayoutMethods};
   6
   7 fn classify_ret<'a, Ty, C>(ret: &mut ArgAbi<'_, Ty>)
   8 where
   9     Ty: TyAndLayoutMethods<'a, C>,
  10     C: LayoutOf<Ty = Ty> + HasDataLayout,
  11 {
  12     if !ret.layout.is_aggregate() && ret.layout.size.bits() <= 64 {
  13         ret.extend_integer_width_to(64);
  14     } else {
  15         ret.make_indirect();
  16     }
  17 }
  18
  19 fn is_single_fp_element<'a, Ty, C>(cx: &C, layout: TyAndLayout<'a, Ty>) -> bool
  20 where
  21     Ty: TyAndLayoutMethods<'a, C>,
  22     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
  23 {
  24     match layout.abi {
  25         abi::Abi::Scalar(ref scalar) => scalar.value.is_float(),
  26         abi::Abi::Aggregate { .. } => {
  27             if layout.fields.count() == 1 && layout.fields.offset(0).bytes() == 0 {
  28                 is_single_fp_element(cx, layout.field(cx, 0))
  29             } else {
  30                 false
  31             }
  32         }
  33         _ => false,
  34     }
  35 }
  36
  37 fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>)
  38 where
  39     Ty: TyAndLayoutMethods<'a, C> + Copy,
  40     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
  41 {
  42     if !arg.layout.is_aggregate() && arg.layout.size.bits() <= 64 {
  43         arg.extend_integer_width_to(64);
  44         return;
  45     }
  46
  47     if is_single_fp_element(cx, arg.layout) {
  48         match arg.layout.size.bytes() {
  49             4 => arg.cast_to(Reg::f32()),
  50             8 => arg.cast_to(Reg::f64()),
  51             _ => arg.make_indirect(),
  52         }
  53     } else {
  54         match arg.layout.size.bytes() {
  55             1 => arg.cast_to(Reg::i8()),
  56             2 => arg.cast_to(Reg::i16()),
  57             4 => arg.cast_to(Reg::i32()),
  58             8 => arg.cast_to(Reg::i64()),
  59             _ => arg.make_indirect(),
  60         }
  61     }
  62 }
  63
  64 pub fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>)
  65 where
  66     Ty: TyAndLayoutMethods<'a, C> + Copy,
  67     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
  68 {
  69     if !fn_abi.ret.is_ignore() {
  70         classify_ret(&mut fn_abi.ret);
  71     }
  72
  73     for arg in &mut fn_abi.args {
  74         if arg.is_ignore() {
  75             continue;
  76         }
  77         classify_arg(cx, arg);
  78     }
  79 }