[wasm] Lazy compilation for asm.js

src/wasm/wasm-objects.h

Index: src/wasm/wasm-objects.h
diff --git a/src/wasm/wasm-objects.h b/src/wasm/wasm-objects.h
index c526a909b1ed2720cc70d6d040315911415f2b34..49f5789917a800af84a472dfb8138b5a63f45548 100644
--- a/src/wasm/wasm-objects.h
+++ b/src/wasm/wasm-objects.h
@@ -164,6 +164,7 @@ class WasmSharedModuleData : public FixedArray {
     kScript,
     kAsmJsOffsetTable,
     kBreakPointInfos,
+    kLazyCompilationOrchestrator,
     kFieldCount
   };
 
@@ -192,6 +193,12 @@ class WasmSharedModuleData : public FixedArray {
 
   static void SetBreakpointsOnNewInstance(Handle<WasmSharedModuleData>,
                                           Handle<WasmInstanceObject>);
+
+  static void PrepareForLazyCompilation(Handle<WasmSharedModuleData>);
+
+ private:
+  DECLARE_OPTIONAL_GETTER(lazy_compilation_orchestrator, Foreign);
+  friend class WasmCompiledModule;
 };
 
 class WasmCompiledModule : public FixedArray {
@@ -400,6 +407,19 @@ class WasmCompiledModule : public FixedArray {
   // FixedArray with all hit breakpoint objects.
   MaybeHandle<FixedArray> CheckBreakPoints(int position);
 
+  // Compile lazily the function called in the given caller code object at the
+  // given offset.
+  // If the called function cannot be termined from the caller (indirect call /
+  // exported function), func_index must be set.
+  // If patch_caller is set, then at least the given all call site in the caller
+  // will be patched, potentially more call sites are updated.
+  // Returns the Code to be called at the given callsite, or an empty Handle if
+  // an error occured during lazy compilation. In this case, an exception has
+  // been set on the isolate.
+  static MaybeHandle<Code> CompileLazy(Isolate*, Handle<WasmInstanceObject>,
+                                       Handle<Code> caller, int offset,
+                                       int func_index, bool patch_caller);
+
  private:
   void InitId();