Add BPF target

This change adds the bpfel-unknown-none and bpfeb-unknown-none targets
which can be used to generate little endian and big endian BPF

2 files changed, 33 insertions, 0 deletions

diff --git a/compiler/rustc_target/src/abi/call/bpf.rs b/compiler/rustc_target/src/abi/call/bpf.rs
new file mode 100644
index 00000000000..79af0150e21
--- /dev/null
+++ b/compiler/rustc_target/src/abi/call/bpf.rs
@@ -0,0 +1,31 @@
+// see BPFCallingConv.td
+use crate::abi::call::{ArgAbi, FnAbi};
+
+fn classify_ret<Ty>(ret: &mut ArgAbi<'_, Ty>) {
+    if ret.layout.is_aggregate() || ret.layout.size.bits() > 64 {
+        ret.make_indirect();
+    } else {
+        ret.extend_integer_width_to(64);
+    }
+}
+
+fn classify_arg<Ty>(arg: &mut ArgAbi<'_, Ty>) {
+    if arg.layout.is_aggregate() || arg.layout.size.bits() > 64 {
+        arg.make_indirect();
+    } else {
+        arg.extend_integer_width_to(64);
+    }
+}
+
+pub fn compute_abi_info<Ty>(fn_abi: &mut FnAbi<'_, Ty>) {
+    if !fn_abi.ret.is_ignore() {
+        classify_ret(&mut fn_abi.ret);
+    }
+
+    for arg in &mut fn_abi.args {
+        if arg.is_ignore() {
+            continue;
+        }
+        classify_arg(arg);
+    }
+}
diff --git a/compiler/rustc_target/src/abi/call/mod.rs b/compiler/rustc_target/src/abi/call/mod.rs
index 0cf2441d84e..864b4fe5f08 100644
--- a/compiler/rustc_target/src/abi/call/mod.rs
+++ b/compiler/rustc_target/src/abi/call/mod.rs
@@ -6,6 +6,7 @@ mod aarch64;
 mod amdgpu;
 mod arm;
 mod avr;
+mod bpf;
 mod hexagon;
 mod mips;
 mod mips64;
@@ -654,6 +655,7 @@ impl<'a, Ty> FnAbi<'a, Ty> {
                 }
             }
             "asmjs" => wasm::compute_c_abi_info(cx, self),
+            "bpfel" | "bpfeb" => bpf::compute_abi_info(self),
             a => return Err(format!("unrecognized arch \"{}\" in target specification", a)),
         }