Unreachable typing fixes (#1004)

* fix type of drop, set_local, set_global, load, etc: when operand is unreachable, so is the node itself

* support binary tests properly in test/passes

* fix unreachable typing of blocks with no name and an unreachable child

* fix continue emitting in asm2wasm

* properly handle emitting of unreachable load

1 files changed, 61 insertions, 0 deletions

diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index 96ca8fbc8..834d9e28f 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -198,6 +198,16 @@ void Block::finalize() {
   if (!name.is()) {
     // nothing branches here, so this is easy
     if (list.size() > 0) {
+      // if we have an unreachable child, we are unreachable
+      // (we don't need to recurse into children, they can't
+      // break to us)
+      for (auto* child : list) {
+        if (child->type == unreachable) {
+          type = unreachable;
+          return;
+        }
+      }
+      // children are reachable, so last element determines type
       type = list.back()->type;
     } else {
       type = none;
@@ -264,6 +274,31 @@ void Switch::finalize() {
   type = unreachable;
 }
 
+template<typename T>
+void handleUnreachableOperands(T* curr) {
+  for (auto* child : curr->operands) {
+    if (child->type == unreachable) {
+      curr->type = unreachable;
+      break;
+    }
+  }
+}
+
+void Call::finalize() {
+  handleUnreachableOperands(this);
+}
+
+void CallImport::finalize() {
+  handleUnreachableOperands(this);
+}
+
+void CallIndirect::finalize() {
+  handleUnreachableOperands(this);
+  if (target->type == unreachable) {
+    type = unreachable;
+  }
+}
+
 bool FunctionType::structuralComparison(FunctionType& b) {
   if (result != b.result) return false;
   if (params.size() != b.params.size()) return false;
@@ -290,6 +325,24 @@ void SetLocal::setTee(bool is) {
   else type = none;
 }
 
+void SetLocal::finalize() {
+  if (value->type == unreachable) {
+    type = unreachable;
+  }
+}
+
+void SetGlobal::finalize() {
+  if (value->type == unreachable) {
+    type = unreachable;
+  }
+}
+
+void Load::finalize() {
+  if (ptr->type == unreachable) {
+    type = unreachable;
+  }
+}
+
 void Store::finalize() {
   assert(valueType != none); // must be set
   if (ptr->type == unreachable || value->type == unreachable) {
@@ -423,6 +476,14 @@ void Select::finalize() {
   }
 }
 
+void Drop::finalize() {
+  if (value->type == unreachable) {
+    type = unreachable;
+  } else {
+    type = none;
+  }
+}
+
 void Host::finalize() {
   switch (op) {
     case PageSize: case CurrentMemory: case HasFeature: {