[wasm] Decouple function name and exported name in WasmFunctionBuilder

src/wasm/wasm-module-builder.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/signature.h"
 
 #include "src/handles.h"
 #include "src/v8.h"
 #include "src/zone/zone-containers.h"
 
@@ skipping 37 matching lines @@
 }
 
 WasmFunctionBuilder::WasmFunctionBuilder(WasmModuleBuilder* builder)
     : builder_(builder),
       locals_(builder->zone()),
       signature_index_(0),
       exported_(0),
       func_index_(static_cast<uint32_t>(builder->functions_.size())),
       body_(builder->zone()),
       name_(builder->zone()),
+      exported_name_(builder->zone()),
       i32_temps_(builder->zone()),
       i64_temps_(builder->zone()),
       f32_temps_(builder->zone()),
       f64_temps_(builder->zone()),
       direct_calls_(builder->zone()) {}
 
 void WasmFunctionBuilder::EmitVarInt(uint32_t val) {
   byte buffer[8];
   byte* ptr = buffer;
   LEBHelper::write_u32v(&ptr, val);
@@ skipping 67 matching lines @@
   DirectCallIndex call;
   call.offset = body_.size();
   call.direct_index = index;
   direct_calls_.push_back(call);
   byte code[] = {U32V_5(0)};
   EmitCode(code, sizeof(code));
 }
 
 void WasmFunctionBuilder::SetExported() { exported_ = true; }
 
+void WasmFunctionBuilder::SetExportedWithName(const char* name,
+                                              int name_length) {
+  exported_ = true;
+  exported_name_.resize(name_length);
+  memcpy(exported_name_.data(), name, name_length);
+}
+
 void WasmFunctionBuilder::SetName(const char* name, int name_length) {
-  name_.clear();
-  if (name_length > 0) {
-    for (int i = 0; i < name_length; ++i) {
-      name_.push_back(*(name + i));
-    }
-  }
+  name_.resize(name_length);
+  memcpy(name_.data(), name, name_length);
 }
 
 void WasmFunctionBuilder::WriteSignature(ZoneBuffer& buffer) const {
   buffer.write_u32v(signature_index_);
 }
 
 void WasmFunctionBuilder::WriteExport(ZoneBuffer& buffer) const {
   if (exported_) {
-    buffer.write_size(name_.size());
-    if (name_.size() > 0) {
-      buffer.write(reinterpret_cast<const byte*>(&name_[0]), name_.size());
-    }
+    const ZoneVector<char>* exported_name =
+        exported_name_.size() == 0 ? &name_ : &exported_name_;
+    buffer.write_size(exported_name->size());
+    buffer.write(reinterpret_cast<const byte*>(exported_name->data()),
+                 exported_name->size());
     buffer.write_u8(kExternalFunction);
     buffer.write_u32v(func_index_ +
                       static_cast<uint32_t>(builder_->imports_.size()));
   }
 }
 
 void WasmFunctionBuilder::WriteBody(ZoneBuffer& buffer) const {
   size_t locals_size = locals_.Size();
   buffer.write_size(locals_size + body_.size());
   buffer.EnsureSpace(locals_size);
@@ skipping 314 matching lines @@
                      function->name_.size());
       }
       buffer.write_u8(0);
     }
     FixupSection(buffer, start, payload_offset);
   }
 }
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8