1 files changed, 31 insertions, 27 deletions

diff --git a/src/passes/DeadCodeElimination.cpp b/src/passes/DeadCodeElimination.cpp
index de1191131..b30b8ffbd 100644
--- a/src/passes/DeadCodeElimination.cpp
+++ b/src/passes/DeadCodeElimination.cpp
@@ -31,6 +31,7 @@
 #include <wasm.h>
 #include <pass.h>
 #include <ast_utils.h>
+#include <wasm-builder.h>
 
 namespace wasm {
 
@@ -131,12 +132,8 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
   }
 
   void visitLoop(Loop* curr) {
-    if (curr->in.is()) {
-      reachableBreaks.erase(curr->in);
-    }
-    if (curr->out.is()) {
-      reachable = reachable || reachableBreaks.count(curr->out);
-      reachableBreaks.erase(curr->out);
+    if (curr->name.is()) {
+      reachableBreaks.erase(curr->name);
     }
     if (isDead(curr->body)) {
       replaceCurrent(curr->body);
@@ -191,6 +188,7 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
         case Expression::Id::UnaryId: DELEGATE(Unary);
         case Expression::Id::BinaryId: DELEGATE(Binary);
         case Expression::Id::SelectId: DELEGATE(Select);
+        case Expression::Id::DropId: DELEGATE(Drop);
         case Expression::Id::ReturnId: DELEGATE(Return);
         case Expression::Id::HostId: DELEGATE(Host);
         case Expression::Id::NopId: DELEGATE(Nop);
@@ -226,46 +224,52 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
 
   // other things
 
+  Expression* drop(Expression* toDrop) {
+    if (toDrop->is<Unreachable>()) return toDrop;
+    return Builder(*getModule()).makeDrop(toDrop);
+  }
+
   template<typename T>
-  void handleCall(T* curr, Expression* initial) {
+  Expression* handleCall(T* curr) {
     for (Index i = 0; i < curr->operands.size(); i++) {
       if (isDead(curr->operands[i])) {
-        if (i > 0 || initial != nullptr) {
+        if (i > 0) {
           auto* block = getModule()->allocator.alloc<Block>();
-          Index newSize = i + 1 + (initial ? 1 : 0);
+          Index newSize = i + 1;
           block->list.resize(newSize);
           Index j = 0;
-          if (initial) {
-            block->list[j] = initial;
-            j++;
-          }
           for (; j < newSize; j++) {
-            block->list[j] = curr->operands[j - (initial ? 1 : 0)];
+            block->list[j] = drop(curr->operands[j]);
           }
           block->finalize();
-          replaceCurrent(block);
+          return replaceCurrent(block);
         } else {
-          replaceCurrent(curr->operands[i]);
+          return replaceCurrent(curr->operands[i]);
         }
-        return;
       }
     }
+    return curr;
   }
 
   void visitCall(Call* curr) {
-    handleCall(curr, nullptr);
+    handleCall(curr);
   }
 
   void visitCallImport(CallImport* curr) {
-    handleCall(curr, nullptr);
+    handleCall(curr);
   }
 
   void visitCallIndirect(CallIndirect* curr) {
+    if (handleCall(curr) != curr) return;
     if (isDead(curr->target)) {
-      replaceCurrent(curr->target);
-      return;
+      auto* block = getModule()->allocator.alloc<Block>();
+      for (auto* operand : curr->operands) {
+        block->list.push_back(drop(operand));
+      }
+      block->list.push_back(curr->target);
+      block->finalize();
+      replaceCurrent(block);
     }
-    handleCall(curr, curr->target);
   }
 
   void visitSetLocal(SetLocal* curr) {
@@ -288,7 +292,7 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
     if (isDead(curr->value)) {
       auto* block = getModule()->allocator.alloc<Block>();
       block->list.resize(2);
-      block->list[0] = curr->ptr;
+      block->list[0] = drop(curr->ptr);
       block->list[1] = curr->value;
       block->finalize();
       replaceCurrent(block);
@@ -309,7 +313,7 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
     if (isDead(curr->right)) {
       auto* block = getModule()->allocator.alloc<Block>();
       block->list.resize(2);
-      block->list[0] = curr->left;
+      block->list[0] = drop(curr->left);
       block->list[1] = curr->right;
       block->finalize();
       replaceCurrent(block);
@@ -324,7 +328,7 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
     if (isDead(curr->ifFalse)) {
       auto* block = getModule()->allocator.alloc<Block>();
       block->list.resize(2);
-      block->list[0] = curr->ifTrue;
+      block->list[0] = drop(curr->ifTrue);
       block->list[1] = curr->ifFalse;
       block->finalize();
       replaceCurrent(block);
@@ -333,8 +337,8 @@ struct DeadCodeElimination : public WalkerPass<PostWalker<DeadCodeElimination, V
     if (isDead(curr->condition)) {
       auto* block = getModule()->allocator.alloc<Block>();
       block->list.resize(3);
-      block->list[0] = curr->ifTrue;
-      block->list[1] = curr->ifFalse;
+      block->list[0] = drop(curr->ifTrue);
+      block->list[1] = drop(curr->ifFalse);
       block->list[2] = curr->condition;
       block->finalize();
       replaceCurrent(block);