[Refactoring] Code reusage in spliceIntoBlock (#4174)

2 files changed, 3 insertions, 11 deletions

diff --git a/src/ir/ExpressionManipulator.cpp b/src/ir/ExpressionManipulator.cpp
index 535aa51c3..0bb94a66d 100644
--- a/src/ir/ExpressionManipulator.cpp
+++ b/src/ir/ExpressionManipulator.cpp
@@ -114,17 +114,7 @@ flexibleCopy(Expression* original, Module& wasm, CustomCopier custom) {
 
 // Splice an item into the middle of a block's list
 void spliceIntoBlock(Block* block, Index index, Expression* add) {
-  auto& list = block->list;
-  if (index == list.size()) {
-    list.push_back(add); // simple append
-  } else {
-    // we need to make room
-    list.push_back(nullptr);
-    for (Index i = list.size() - 1; i > index; i--) {
-      list[i] = list[i - 1];
-    }
-    list[index] = add;
-  }
+  block->list.insertAt(index, add);
   block->finalize(block->type);
 }
 
diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index 45137fffe..0f1017e00 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -821,6 +821,7 @@ void Try::finalize() {
   // If none of the component bodies' type is a supertype of the others, assume
   // the current type is already correct. TODO: Calculate a proper LUB.
   std::unordered_set<Type> types{body->type};
+  types.reserve(catchBodies.size());
   for (auto catchBody : catchBodies) {
     types.insert(catchBody->type);
   }
@@ -844,6 +845,7 @@ void Rethrow::finalize() { type = Type::unreachable; }
 
 void TupleMake::finalize() {
   std::vector<Type> types;
+  types.reserve(operands.size());
   for (auto* op : operands) {
     if (op->type == Type::unreachable) {
       type = Type::unreachable;