From 2a9da447b515f6e06a23d41922f5e07dc6c6ef6f Mon Sep 17 00:00:00 2001
From: Yoshitomo Nakanishi <yurayura.rounin.3@gmail.com>
Date: Sat, 7 Sep 2024 16:55:50 +0200
Subject: [PATCH] Implement a macro to provide an easy way to define `Inst`
 types

---
 crates/ir/src/inst.rs | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/crates/ir/src/inst.rs b/crates/ir/src/inst.rs
index 5deb8739..8be3e220 100644
--- a/crates/ir/src/inst.rs
+++ b/crates/ir/src/inst.rs
@@ -6,3 +6,43 @@ pub trait Inst {
     fn has_side_effect(&self) -> bool;
     fn as_str(&self) -> &'static str;
 }
+
+macro_rules! define_inst {
+    ($(($purity:ident, $ty:ident, $name:literal, $arity:literal)),* $(,)?) => {
+        $(
+            define_inst!($purity, $ty, $name, $arity);
+        )*
+    };
+
+    ($purity: ident, $ty: ident, $name:literal, $arity:literal) => {
+        pub struct $ty {
+            args: [Value; $arity],
+        }
+
+        impl Inst for $ty {
+            fn args(&self) -> &[Value] {
+                &self.args
+            }
+
+            fn args_mut(&mut self) -> &mut [Value] {
+                &mut self.args
+            }
+
+            fn has_side_effect(&self) -> bool {
+                define_inst!(has_side_effect_impl $purity)
+            }
+
+            fn as_str(&self) -> &'static str {
+                $name
+            }
+        }
+    };
+
+   (has_side_effect_impl pure) => {
+       true
+   };
+
+   (has_side_effect_impl non_pure) => {
+       true
+   };
+}