[wasm] First step to separate graph construction from graph compilation.

src/compiler/pipeline.cc

Index: src/compiler/pipeline.cc
diff --git a/src/compiler/pipeline.cc b/src/compiler/pipeline.cc
index e29c5d2f3c40761c86ccfb1efe6319fc41327385..b158d8b37ac32c37914556c0c36417c031e57d62 100644
--- a/src/compiler/pipeline.cc
+++ b/src/compiler/pipeline.cc
@@ -73,7 +73,7 @@ namespace v8 {
 namespace internal {
 namespace compiler {
 
-class PipelineData {
+class PipelineData : public ZoneObject {
  public:
   // For main entry point.
   PipelineData(ZonePool* zone_pool, CompilationInfo* info,
@@ -172,12 +172,14 @@ class PipelineData {
         register_allocation_zone_(register_allocation_zone_scope_.zone()),
         register_allocation_data_(nullptr) {}
 
-  ~PipelineData() {
+  void Destroy() {
     DeleteRegisterAllocationZone();
     DeleteInstructionZone();
     DeleteGraphZone();
   }
 
+  ~PipelineData() { Destroy(); }
+
   Isolate* isolate() const { return isolate_; }
   CompilationInfo* info() const { return info_; }
   ZonePool* zone_pool() const { return zone_pool_; }
@@ -1396,6 +1398,14 @@ Handle<Code> Pipeline::GenerateCodeForTesting(CompilationInfo* info,
   return pipeline.ScheduleAndGenerateCode(call_descriptor);
 }
 
+void Pipeline::InitializeWasmCompilation(Zone* pipeline_zone,
+                                         ZonePool* zone_pool, Graph* graph) {
+  data_ = new (pipeline_zone) PipelineData(zone_pool, info(), graph, nullptr);
+  RunPrintAndVerify("Machine", true);
+}
+
+void Pipeline::FinalizeWasmCompilation() { data_->Destroy(); }
+
 OptimizedCompileJob* Pipeline::NewCompilationJob(CompilationInfo* info) {
   return new (info->zone()) PipelineCompilationJob(info);
 }
@@ -1418,6 +1428,7 @@ Handle<Code> Pipeline::ScheduleAndGenerateCode(
     CallDescriptor* call_descriptor) {
   PipelineData* data = this->data_;
 
+  DCHECK_NOT_NULL(data);
   DCHECK_NOT_NULL(data->graph());
 
   if (data->schedule() == nullptr) Run<ComputeSchedulePhase>();