Implement Wasm GrowMemory opcode as a wasm runtime call

src/compiler/wasm-compiler.cc

Index: src/compiler/wasm-compiler.cc
diff --git a/src/compiler/wasm-compiler.cc b/src/compiler/wasm-compiler.cc
index 0a13f98d8593f32e8990752d7d1a64451314ae6d..a6fb886d3726e13db7f7b8f7fb296c31c9817084 100644
--- a/src/compiler/wasm-compiler.cc
+++ b/src/compiler/wasm-compiler.cc
@@ -881,6 +881,8 @@ Node* WasmGraphBuilder::Unop(wasm::WasmOpcode opcode, Node* input,
       return BuildI64UConvertF32(input, position);
     case wasm::kExprI64UConvertF64:
       return BuildI64UConvertF64(input, position);
+    case wasm::kExprGrowMemory:
+      return BuildGrowMemory(input);
     case wasm::kExprI32AsmjsLoadMem8S:
       return BuildAsmjsLoadMem(MachineType::Int8(), input);
     case wasm::kExprI32AsmjsLoadMem8U:
@@ -1571,6 +1573,35 @@ Node* WasmGraphBuilder::BuildFloatToIntConversionInstruction(
   return load;
 }
 
+Node* WasmGraphBuilder::BuildGrowMemory(Node* input) {
+  Runtime::FunctionId function_id = Runtime::kWasmGrowMemory;
+  const Runtime::Function* function = Runtime::FunctionForId(function_id);
+  CallDescriptor* desc = Linkage::GetRuntimeCallDescriptor(
+      jsgraph()->zone(), function_id, function->nargs, Operator::kNoProperties,
+      CallDescriptor::kNoFlags);
+  Node** control_ptr = control_;
+  Node** effect_ptr = effect_;
+  wasm::ModuleEnv* module = module_;
+  *control_ptr = graph()->NewNode(jsgraph()->common()->Merge(1), *control_ptr);

[ahaas, 2016/06/27 15:08:25]

why do you create a Merge and an EffectPhi node here? Can you add a test which
fails when these nodes are missing?

[gdeepti, 2016/06/27 19:18:54]

I misunderstood how control/effect pointers should be updated for runtime
functions. Merge and an EffectPhi nodes not required here, removed now. 

+  *effect_ptr = graph()->NewNode(jsgraph()->common()->EffectPhi(1), *effect_ptr,
+                                 *control_ptr);
+  input = BuildChangeUint32ToSmi(input);
+  Node* inputs[] = {
+      jsgraph()->CEntryStubConstant(function->result_size), input,  // C entry
+      jsgraph()->ExternalConstant(
+          ExternalReference(function_id, jsgraph()->isolate())),  // ref
+      jsgraph()->Int32Constant(function->nargs),                  // arity
+      jsgraph()->HeapConstant(module->instance->context),         // context
+      *effect_ptr,
+      *control_ptr};
+  Node* node = graph()->NewNode(jsgraph()->common()->Call(desc),
+                                static_cast<int>(arraysize(inputs)), inputs);
+  *control_ptr = node;
+  *effect_ptr = node;
+  node = BuildChangeSmiToInt32(node);
+  return node;
+}
+
 Node* WasmGraphBuilder::BuildI32DivS(Node* left, Node* right,
                                      wasm::WasmCodePosition position) {
   MachineOperatorBuilder* m = jsgraph()->machine();
@@ -2283,6 +2314,15 @@ Node* WasmGraphBuilder::BuildChangeSmiToInt32(Node* value) {
   return value;
 }
 
+Node* WasmGraphBuilder::BuildChangeUint32ToSmi(Node* value) {
+  if (jsgraph()->machine()->Is64()) {
+    value =
+        graph()->NewNode(jsgraph()->machine()->ChangeUint32ToUint64(), value);
+  }
+  return graph()->NewNode(jsgraph()->machine()->WordShl(), value,
+                          BuildSmiShiftBitsConstant());
+}
+
 Node* WasmGraphBuilder::BuildChangeSmiToFloat64(Node* value) {
   return graph()->NewNode(jsgraph()->machine()->ChangeInt32ToFloat64(),
                           BuildChangeSmiToInt32(value));
@@ -2588,7 +2628,6 @@ void WasmGraphBuilder::BoundsCheckMem(MachineType memtype, Node* index,
                                 jsgraph()->RelocatableInt32Constant(
                                     static_cast<uint32_t>(effective_size),
                                     RelocInfo::WASM_MEMORY_SIZE_REFERENCE));
-
   trap_->AddTrapIfFalse(wasm::kTrapMemOutOfBounds, cond, position);
 }