[Wasm GC] Add static variants of ref.test, ref.cast, and br_on_cast* (#4163)

These variants take a HeapType that is the type we intend to cast to,
and do not take an RTT.

These are intended to be more statically optimizable. For now though
this PR just implements the minimum to get them parsing and to get
through the optimizer without crashing.

Spec: https://docs.google.com/document/d/1afthjsL_B9UaMqCA5ekgVmOm75BVFu6duHNsN9-gnXw/edit#

See #4149

1 files changed, 29 insertions, 4 deletions

diff --git a/src/wasm/wasm-stack.cpp b/src/wasm/wasm-stack.cpp
index e5460cf6f..b6424cdde 100644
--- a/src/wasm/wasm-stack.cpp
+++ b/src/wasm/wasm-stack.cpp
@@ -1942,11 +1942,23 @@ void BinaryInstWriter::visitCallRef(CallRef* curr) {
 }
 
 void BinaryInstWriter::visitRefTest(RefTest* curr) {
-  o << int8_t(BinaryConsts::GCPrefix) << U32LEB(BinaryConsts::RefTest);
+  o << int8_t(BinaryConsts::GCPrefix);
+  if (curr->rtt) {
+    o << U32LEB(BinaryConsts::RefTest);
+  } else {
+    o << U32LEB(BinaryConsts::RefTestStatic);
+    parent.writeIndexedHeapType(curr->intendedType);
+  }
 }
 
 void BinaryInstWriter::visitRefCast(RefCast* curr) {
-  o << int8_t(BinaryConsts::GCPrefix) << U32LEB(BinaryConsts::RefCast);
+  o << int8_t(BinaryConsts::GCPrefix);
+  if (curr->rtt) {
+    o << U32LEB(BinaryConsts::RefCast);
+  } else {
+    o << U32LEB(BinaryConsts::RefCastStatic);
+    parent.writeIndexedHeapType(curr->intendedType);
+  }
 }
 
 void BinaryInstWriter::visitBrOn(BrOn* curr) {
@@ -1958,10 +1970,20 @@ void BinaryInstWriter::visitBrOn(BrOn* curr) {
       o << int8_t(BinaryConsts::BrOnNonNull);
       break;
     case BrOnCast:
-      o << int8_t(BinaryConsts::GCPrefix) << U32LEB(BinaryConsts::BrOnCast);
+      o << int8_t(BinaryConsts::GCPrefix);
+      if (curr->rtt) {
+        o << U32LEB(BinaryConsts::BrOnCast);
+      } else {
+        o << U32LEB(BinaryConsts::BrOnCastStatic);
+      }
       break;
     case BrOnCastFail:
-      o << int8_t(BinaryConsts::GCPrefix) << U32LEB(BinaryConsts::BrOnCastFail);
+      o << int8_t(BinaryConsts::GCPrefix);
+      if (curr->rtt) {
+        o << U32LEB(BinaryConsts::BrOnCastFail);
+      } else {
+        o << U32LEB(BinaryConsts::BrOnCastStaticFail);
+      }
       break;
     case BrOnFunc:
       o << int8_t(BinaryConsts::GCPrefix) << U32LEB(BinaryConsts::BrOnFunc);
@@ -1985,6 +2007,9 @@ void BinaryInstWriter::visitBrOn(BrOn* curr) {
       WASM_UNREACHABLE("invalid br_on_*");
   }
   o << U32LEB(getBreakIndex(curr->name));
+  if ((curr->op == BrOnCast || curr->op == BrOnCastFail) && !curr->rtt) {
+    parent.writeIndexedHeapType(curr->intendedType);
+  }
 }
 
 void BinaryInstWriter::visitRttCanon(RttCanon* curr) {