[GC] Add Array operations (#3436)

array.new/get/set/len - pretty straightforward after structs and all the
infrastructure for them.

Also fixes validation of the unnecessary heapType param in the
text and binary formats in structs as well as arrays.

Fixes printing of packed types in type names, which emitted i32
for them. That broke when we emitted the same name for an array
of i8 and i32 as in the new testing here.

Also fix a bug in Field::operator< which was wrong for packed
types; again, this was easy to notice with the new testing.

1 files changed, 68 insertions, 11 deletions

diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index e97541444..cf92cf4d3 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -2277,14 +2277,19 @@ void FunctionValidator::visitStructGet(StructGet* curr) {
   shouldBeTrue(getModule()->features.hasGC(),
                curr,
                "struct.get requires gc to be enabled");
-  if (curr->ref->type != Type::unreachable) {
-    const auto& fields = curr->ref->type.getHeapType().getStruct().fields;
-    shouldBeTrue(curr->index < fields.size(), curr, "bad struct.get field");
-    shouldBeEqual(curr->type,
-                  fields[curr->index].type,
-                  curr,
-                  "struct.get must have the proper type");
+  const auto& fields = curr->ref->type.getHeapType().getStruct().fields;
+  shouldBeTrue(curr->index < fields.size(), curr, "bad struct.get field");
+  auto field = fields[curr->index];
+  // If the type is not packed, it must be marked internally as unsigned, by
+  // convention.
+  if (field.type != Type::i32 || field.packedType == Field::not_packed) {
+    shouldBeFalse(curr->signed_, curr, "non-packed get cannot be signed");
+  }
+  if (curr->ref->type == Type::unreachable) {
+    return;
   }
+  shouldBeEqual(
+    curr->type, field.type, curr, "struct.get must have the proper type");
 }
 
 void FunctionValidator::visitStructSet(StructSet* curr) {
@@ -2304,25 +2309,77 @@ void FunctionValidator::visitStructSet(StructSet* curr) {
 void FunctionValidator::visitArrayNew(ArrayNew* curr) {
   shouldBeTrue(
     getModule()->features.hasGC(), curr, "array.new requires gc to be enabled");
-  WASM_UNREACHABLE("TODO (gc): array.new");
+  shouldBeEqualOrFirstIsUnreachable(
+    curr->size->type, Type(Type::i32), curr, "array.new size must be an i32");
+  if (curr->type == Type::unreachable) {
+    return;
+  }
+  if (!shouldBeTrue(
+        curr->rtt->type.isRtt(), curr, "array.new rtt must be rtt")) {
+    return;
+  }
+  auto heapType = curr->rtt->type.getHeapType();
+  if (!shouldBeTrue(
+        heapType.isArray(), curr, "array.new heap type must be array")) {
+    return;
+  }
+  const auto& element = heapType.getArray().element;
+  if (curr->isWithDefault()) {
+    shouldBeTrue(
+      !curr->init, curr, "array.new_with_default should have no init");
+    // The element must be defaultable.
+    // TODO: add type.isDefaultable()?
+    shouldBeTrue(!element.type.isRef() || element.type.isNullable(),
+                 element,
+                 "array.new_with_default value type must be defaultable");
+  } else {
+    shouldBeTrue(!!curr->init, curr, "array.new should have an init");
+    // The inits must have the proper type.
+    shouldBeSubType(curr->init->type,
+                    element.type,
+                    curr,
+                    "array.new init must have proper type");
+  }
 }
 
 void FunctionValidator::visitArrayGet(ArrayGet* curr) {
   shouldBeTrue(
     getModule()->features.hasGC(), curr, "array.get requires gc to be enabled");
-  WASM_UNREACHABLE("TODO (gc): array.get");
+  shouldBeEqualOrFirstIsUnreachable(
+    curr->index->type, Type(Type::i32), curr, "array.get index must be an i32");
+  const auto& element = curr->ref->type.getHeapType().getArray().element;
+  // If the type is not packed, it must be marked internally as unsigned, by
+  // convention.
+  if (element.type != Type::i32 || element.packedType == Field::not_packed) {
+    shouldBeFalse(curr->signed_, curr, "non-packed get cannot be signed");
+  }
+  if (curr->type == Type::unreachable) {
+    return;
+  }
+  shouldBeEqual(
+    curr->type, element.type, curr, "array.get must have the proper type");
 }
 
 void FunctionValidator::visitArraySet(ArraySet* curr) {
   shouldBeTrue(
     getModule()->features.hasGC(), curr, "array.set requires gc to be enabled");
-  WASM_UNREACHABLE("TODO (gc): array.set");
+  shouldBeEqualOrFirstIsUnreachable(
+    curr->index->type, Type(Type::i32), curr, "array.set index must be an i32");
+  if (curr->type == Type::unreachable) {
+    return;
+  }
+  const auto& element = curr->ref->type.getHeapType().getArray().element;
+  shouldBeEqual(curr->value->type,
+                element.type,
+                curr,
+                "array.set must have the proper type");
 }
 
 void FunctionValidator::visitArrayLen(ArrayLen* curr) {
   shouldBeTrue(
     getModule()->features.hasGC(), curr, "array.len requires gc to be enabled");
-  WASM_UNREACHABLE("TODO (gc): array.len");
+  shouldBeEqualOrFirstIsUnreachable(
+    curr->type, Type(Type::i32), curr, "array.len result must be an i32");
 }
 
 void FunctionValidator::visitFunction(Function* curr) {