GC: Add i31 instructions (#3154)

Adds the `i31.new` and `i31.get_s/u` instructions for creating and working with `i31ref` typed values. Does not include fuzzer integration just yet because the fuzzer expects that trivial values it creates are suitable in global initializers, which is not the case for trivial `i31ref` expressions.

4 files changed, 128 insertions, 0 deletions

diff --git a/test/binaryen.js/expressions.js b/test/binaryen.js/expressions.js
index a97097afe..0d48e5551 100644
--- a/test/binaryen.js/expressions.js
+++ b/test/binaryen.js/expressions.js
@@ -1649,3 +1649,60 @@ console.log("# TupleExtract");
 
   module.dispose();
 })();
+
+console.log("# I31New");
+(function testI31New() {
+  const module = new binaryen.Module();
+
+  var value = module.local.get(1, binaryen.i32);
+  const theI31New = binaryen.I31New(module.i31.new(value));
+  assert(theI31New instanceof binaryen.I31New);
+  assert(theI31New instanceof binaryen.Expression);
+  assert(theI31New.value === value);
+  assert(theI31New.type === binaryen.i31ref);
+
+  theI31New.value = value = module.local.get(2, binaryen.i32);
+  assert(theI31New.value === value);
+  theI31New.type = binaryen.f64;
+  theI31New.finalize();
+  assert(theI31New.type === binaryen.i31ref);
+
+  console.log(theI31New.toText());
+  assert(
+    theI31New.toText()
+    ==
+    "(i31.new\n (local.get $2)\n)\n"
+  );
+
+  module.dispose();
+})();
+
+console.log("# I31Get");
+(function testI31Get() {
+  const module = new binaryen.Module();
+
+  var i31 = module.local.get(1, binaryen.i31ref);
+  const theI31Get = binaryen.I31Get(module.i31.get_s(i31));
+  assert(theI31Get instanceof binaryen.I31Get);
+  assert(theI31Get instanceof binaryen.Expression);
+  assert(theI31Get.i31 === i31);
+  assert(theI31Get.signed === true);
+  assert(theI31Get.type === binaryen.i32);
+
+  theI31Get.i31 = i31 = module.local.get(2, binaryen.i31ref);
+  assert(theI31Get.i31 === i31);
+  theI31Get.signed = false;
+  assert(theI31Get.signed === false);
+  theI31Get.type = binaryen.f64;
+  theI31Get.finalize();
+  assert(theI31Get.type === binaryen.i32);
+
+  console.log(theI31Get.toText());
+  assert(
+    theI31Get.toText()
+    ==
+    "(i31.get_u\n (local.get $2)\n)\n"
+  );
+
+  module.dispose();
+})();
diff --git a/test/binaryen.js/expressions.js.txt b/test/binaryen.js/expressions.js.txt
index 22c4f2747..e2b34e501 100644
--- a/test/binaryen.js/expressions.js.txt
+++ b/test/binaryen.js/expressions.js.txt
@@ -256,3 +256,13 @@
  )
 )
 
+# I31New
+(i31.new
+ (local.get $2)
+)
+
+# I31Get
+(i31.get_u
+ (local.get $2)
+)
+
diff --git a/test/binaryen.js/kitchen-sink.js b/test/binaryen.js/kitchen-sink.js
index f699e96e0..051f53c54 100644
--- a/test/binaryen.js/kitchen-sink.js
+++ b/test/binaryen.js/kitchen-sink.js
@@ -165,6 +165,10 @@ function test_ids() {
   console.log("ThrowId: " + binaryen.ThrowId);
   console.log("RethrowId: " + binaryen.RethrowId);
   console.log("BrOnExnId: " + binaryen.BrOnExnId);
+  console.log("TupleMakeId: " + binaryen.TupleMakeId);
+  console.log("TupleExtractId: " + binaryen.TupleExtractId);
+  console.log("I31NewId: " + binaryen.I31NewId);
+  console.log("I31GetId: " + binaryen.I31GetId);
 }
 
 function test_core() {
@@ -595,6 +599,21 @@ function test_core() {
     module.memory.size(),
     module.memory.grow(makeInt32(0)),
 
+    // GC
+    module.i31.new(
+      module.i32.const(0)
+    ),
+    module.i31.get_s(
+      module.i31.new(
+        module.i32.const(1)
+      )
+    ),
+    module.i31.get_u(
+      module.i31.new(
+        module.i32.const(2)
+      )
+    ),
+
     // Other
     module.nop(),
     module.unreachable(),
diff --git a/test/binaryen.js/kitchen-sink.js.txt b/test/binaryen.js/kitchen-sink.js.txt
index 1c11e787e..9fca3ae53 100644
--- a/test/binaryen.js/kitchen-sink.js.txt
+++ b/test/binaryen.js/kitchen-sink.js.txt
@@ -89,6 +89,10 @@ TryId: 44
 ThrowId: 45
 RethrowId: 46
 BrOnExnId: 47
+TupleMakeId: 48
+TupleExtractId: 49
+I31NewId: 50
+I31GetId: 51
 getExpressionInfo={"id":15,"type":4,"op":6}
 (f32.neg
  (f32.const -33.61199951171875)
@@ -1952,6 +1956,25 @@ getExpressionInfo(tuple[3])={"id":14,"type":5,"value":3.7}
         (i32.const 0)
        )
       )
+      (drop
+       (i31.new
+        (i32.const 0)
+       )
+      )
+      (drop
+       (i31.get_s
+        (i31.new
+         (i32.const 1)
+        )
+       )
+      )
+      (drop
+       (i31.get_u
+        (i31.new
+         (i32.const 2)
+        )
+       )
+      )
       (nop)
       (unreachable)
      )
@@ -3815,6 +3838,25 @@ getExpressionInfo(tuple[3])={"id":14,"type":5,"value":3.7}
         (i32.const 0)
        )
       )
+      (drop
+       (i31.new
+        (i32.const 0)
+       )
+      )
+      (drop
+       (i31.get_s
+        (i31.new
+         (i32.const 1)
+        )
+       )
+      )
+      (drop
+       (i31.get_u
+        (i31.new
+         (i32.const 2)
+        )
+       )
+      )
       (nop)
       (unreachable)
      )