Add for loop to asm-to-wasm

src/wasm/asm-wasm-builder.cc

Index: src/wasm/asm-wasm-builder.cc
diff --git a/src/wasm/asm-wasm-builder.cc b/src/wasm/asm-wasm-builder.cc
index 88049b8520bc7f07a32dc3761ebbd1ce054d94a3..a0cabb24d3b4fe24c536ab5251aa8805268dc716 100644
--- a/src/wasm/asm-wasm-builder.cc
+++ b/src/wasm/asm-wasm-builder.cc
@@ -226,16 +226,39 @@ class AsmWasmBuilderImpl : public AstVisitor {
   }
 
   void VisitForStatement(ForStatement* stmt) {
+    DCHECK(in_function_);
     if (stmt->init() != NULL) {
+      block_size_++;
       RECURSE(Visit(stmt->init()));
     }
+    current_function_builder_->Emit(kExprLoop);
+    uint32_t index = current_function_builder_->EmitEditableImmediate(0);
+    int prev_block_size = block_size_;
+    block_size_ = 0;
+    breakable_blocks_.push_back(
+        std::make_pair(stmt->AsBreakableStatement(), true));
     if (stmt->cond() != NULL) {
+      block_size_++;
+      current_function_builder_->Emit(kExprIf);
+      current_function_builder_->Emit(kExprBoolNot);
       RECURSE(Visit(stmt->cond()));
+      current_function_builder_->EmitWithU8(kExprBr, 1);
+      current_function_builder_->Emit(kExprNop);
+    }
+    if (stmt->body() != NULL) {
+      block_size_++;
+      RECURSE(Visit(stmt->body()));
     }
     if (stmt->next() != NULL) {
+      block_size_++;
       RECURSE(Visit(stmt->next()));
     }
-    RECURSE(Visit(stmt->body()));
+    block_size_++;
+    current_function_builder_->EmitWithU8(kExprBr, 0);
+    current_function_builder_->Emit(kExprNop);
+    current_function_builder_->EditImmediate(index, block_size_);
+    block_size_ = prev_block_size;
+    breakable_blocks_.pop_back();
   }
 
   void VisitForInStatement(ForInStatement* stmt) {

[bradnelson, 2015/12/15 03:07:04]

Unrelated to this CL, but since for..in, for..of, try..catch, try..finally are
forbidden by the typer, maybe switch them to UNREACHABLE(); in another CL.