compiler/rustc_target/src/abi/call/wasm32.rs

   1 use crate::abi::call::{ArgAbi, FnAbi, Uniform};
   2 use crate::abi::{HasDataLayout, LayoutOf, TyAndLayout, TyAndLayoutMethods};
   3
   4 fn unwrap_trivial_aggregate<'a, Ty, C>(cx: &C, val: &mut ArgAbi<'a, Ty>) -> bool
   5 where
   6     Ty: TyAndLayoutMethods<'a, C> + Copy,
   7     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
   8 {
   9     if val.layout.is_aggregate() {
  10         if let Some(unit) = val.layout.homogeneous_aggregate(cx).ok().and_then(|ha| ha.unit()) {
  11             let size = val.layout.size;
  12             if unit.size == size {
  13                 val.cast_to(Uniform { unit, total: size });
  14                 return true;
  15             }
  16         }
  17     }
  18     false
  19 }
  20
  21 fn classify_ret<'a, Ty, C>(cx: &C, ret: &mut ArgAbi<'a, Ty>)
  22 where
  23     Ty: TyAndLayoutMethods<'a, C> + Copy,
  24     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
  25 {
  26     ret.extend_integer_width_to(32);
  27     if ret.layout.is_aggregate() {
  28         if !unwrap_trivial_aggregate(cx, ret) {
  29             ret.make_indirect();
  30         }
  31     }
  32 }
  33
  34 fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>)
  35 where
  36     Ty: TyAndLayoutMethods<'a, C> + Copy,
  37     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
  38 {
  39     arg.extend_integer_width_to(32);
  40     if arg.layout.is_aggregate() {
  41         if !unwrap_trivial_aggregate(cx, arg) {
  42             arg.make_indirect_byval();
  43         }
  44     }
  45 }
  46
  47 pub fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>)
  48 where
  49     Ty: TyAndLayoutMethods<'a, C> + Copy,
  50     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
  51 {
  52     if !fn_abi.ret.is_ignore() {
  53         classify_ret(cx, &mut fn_abi.ret);
  54     }
  55
  56     for arg in &mut fn_abi.args {
  57         if arg.is_ignore() {
  58             continue;
  59         }
  60         classify_arg(cx, arg);
  61     }
  62 }