From f1be72f9d393593a00eb508a3e8365853d7e372d Mon Sep 17 00:00:00 2001
From: Sam Zhou <sam@developersam.com>
Date: Sat, 14 Dec 2024 13:49:58 -0500
Subject: [PATCH] [wasm][ast] Support `ref.cast` instruction

---
 crates/samlang-ast/src/wasm.rs | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/crates/samlang-ast/src/wasm.rs b/crates/samlang-ast/src/wasm.rs
index 25c55f25..1d213c11 100644
--- a/crates/samlang-ast/src/wasm.rs
+++ b/crates/samlang-ast/src/wasm.rs
@@ -10,6 +10,10 @@ pub enum InlineInstruction {
     pointer_type: String,
     value: Box<InlineInstruction>,
   },
+  Cast {
+    pointer_type: String,
+    value: Box<InlineInstruction>,
+  },
   Binary(Box<InlineInstruction>, hir::BinaryOperator, Box<InlineInstruction>),
   Load {
     index: usize,
@@ -60,6 +64,13 @@ impl InlineInstruction {
         value.pretty_print(collector, heap, table);
         collector.push(')');
       }
+      InlineInstruction::Cast { pointer_type, value } => {
+        collector.push_str("(ref.cast $");
+        collector.push_str(pointer_type);
+        collector.push(' ');
+        value.pretty_print(collector, heap, table);
+        collector.push(')');
+      }
       InlineInstruction::Binary(v1, op, v2) => {
         let op_s = match op {
           hir::BinaryOperator::MUL => "mul",
@@ -377,6 +388,10 @@ mod tests {
                 pointer_type: "Foo".to_string(),
                 value: Box::new(InlineInstruction::Const(0)),
               }),
+              Instruction::Inline(InlineInstruction::Cast {
+                pointer_type: "Foo".to_string(),
+                value: Box::new(InlineInstruction::Const(0)),
+              }),
             ],
             s2: vec![
               Instruction::Inline(InlineInstruction::Binary(
@@ -520,6 +535,7 @@ mod tests {
     (local.get $a)
     (local.set $b (i32.const 0))
     (ref.test $Foo (i32.const 0))
+    (ref.cast $Foo (i32.const 0))
   ) (else
     (i32.add (i32.const 0) (i32.const 0))
     (i32.sub (i32.const 0) (i32.const 0))