Implement Wasm GrowMemory opcode as a wasm runtime call

src/wasm/wasm-module.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/base/atomic-utils.h"
 #include "src/macro-assembler.h"
 #include "src/objects.h"
 #include "src/property-descriptor.h"
 #include "src/v8.h"
 
@@ skipping 1008 matching lines @@
 }
 
 WasmDebugInfo* GetDebugInfo(JSObject* wasm) {
   Object* info = wasm->GetInternalField(kWasmDebugInfo);
   if (!info->IsUndefined(wasm->GetIsolate())) return WasmDebugInfo::cast(info);
   Handle<WasmDebugInfo> new_info = WasmDebugInfo::New(handle(wasm));
   wasm->SetInternalField(kWasmDebugInfo, *new_info);
   return *new_info;
 }
 
+bool UpdateWasmModuleMemory(JSObject* object, byte* old_start, byte* new_start,
+                            uint32_t old_size, uint32_t new_size) {
+  if (!IsWasmObject(object)) {
+    return false;
+  }
+
+  // Get code table associated with the module js_object
+  Object* obj = object->GetInternalField(kWasmModuleCodeTable);
+  Handle<FixedArray> code_table;
+  code_table = Handle<FixedArray>(FixedArray::cast(obj));
+
+  // Iterate through the code objects in the code table and update relocation
+  // information
+  for (int i = 0; i < code_table->length(); i++) {
+    Handle<Code> code;
+    obj = code_table->get(i);
+    code = Handle<Code>(Code::cast(obj));

[ahaas, 2016/06/24 11:10:15]

Why don't you just say Handle<Code> code(Code::cast(obj));?

[gdeepti, 2016/06/25 00:28:41]

Done.

+
+    int mode_mask = RelocInfo::ModeMask(RelocInfo::WASM_MEMORY_REFERENCE) |
+                    RelocInfo::ModeMask(RelocInfo::WASM_MEMORY_SIZE_REFERENCE);
+    for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
+      RelocInfo::Mode mode = it.rinfo()->rmode();
+      if (RelocInfo::IsWasmMemoryReference(mode) ||
+          RelocInfo::IsWasmMemorySizeReference(mode)) {
+        it.rinfo()->update_wasm_memory_reference(
+            reinterpret_cast<Address>(old_start),
+            reinterpret_cast<Address>(new_start), old_size, new_size);
+      }
+    }
+  }
+  return true;
+}
+
 namespace testing {
 
 int32_t CompileAndRunWasmModule(Isolate* isolate, const byte* module_start,
                                 const byte* module_end, bool asm_js) {
   HandleScope scope(isolate);
   Zone zone(isolate->allocator());
   ErrorThrower thrower(isolate, "CompileAndRunWasmModule");
 
   // Decode the module, but don't verify function bodies, since we'll
   // be compiling them anyway.
@@ skipping 51 matching lines @@
     return static_cast<int32_t>(HeapNumber::cast(*result)->value());
   }
   thrower.Error("WASM.compileRun() failed: Return value should be number");
   return -1;
 }
 
 }  // namespace testing
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8