--- /dev/null
+use crate::abi::call::{ArgAbi, FnAbi, Reg};
+use crate::abi::Abi;
+
+// 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::ScalarPair(..) | Abi::Aggregate { .. } => 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(_) => {
+ if a.layout.size.bytes() > 8 {
+ a.make_indirect();
+ } else {
+ a.extend_integer_width_to(32);
+ }
+ }
+ }
+ };
+
+ if !fn_abi.ret.is_ignore() {
+ fixup(&mut fn_abi.ret);
+ }
+ for arg in &mut fn_abi.args {
+ if arg.is_ignore() {
+ continue;
+ }
+ fixup(arg);
+ }
+}