Implement Wasm GrowMemory opcode as a wasm runtime call

src/compiler/wasm-compiler.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/compiler/wasm-compiler.h"
 
 #include "src/isolate-inl.h"
 
 #include "src/base/platform/elapsed-timer.h"
 #include "src/base/platform/platform.h"
@@ skipping 859 matching lines @@
       op = m->RoundUint64ToFloat64();
       break;
     case wasm::kExprI64SConvertF32:
       return BuildI64SConvertF32(input, position);
     case wasm::kExprI64SConvertF64:
       return BuildI64SConvertF64(input, position);
     case wasm::kExprI64UConvertF32:
       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:
       return BuildAsmjsLoadMem(MachineType::Uint8(), input);
     case wasm::kExprI32AsmjsLoadMem16S:
       return BuildAsmjsLoadMem(MachineType::Int16(), input);
     case wasm::kExprI32AsmjsLoadMem16U:
       return BuildAsmjsLoadMem(MachineType::Uint16(), input);
     case wasm::kExprI32AsmjsLoadMem:
       return BuildAsmjsLoadMem(MachineType::Int32(), input);
@@ skipping 708 matching lines @@
   trap_->ZeroCheck32(wasm::kTrapFloatUnrepresentable,
                      BuildCCall(sig_builder.Build(), args), position);
   const Operator* load_op = jsgraph()->machine()->Load(result_type);
   Node* load =
       graph()->NewNode(load_op, stack_slot_result, jsgraph()->Int32Constant(0),
                        *effect_, *control_);
   *effect_ = load;
   return load;
 }
 
+Node* WasmGraphBuilder::BuildGrowMemory(Node* input) {
+  Runtime::FunctionId f = Runtime::kWasmGrowMemory;
+  const Runtime::Function* fun = Runtime::FunctionForId(f);
+  CallDescriptor* desc = Linkage::GetRuntimeCallDescriptor(
+      jsgraph()->zone(), f, fun->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);
+  *effect_ptr = graph()->NewNode(jsgraph()->common()->EffectPhi(1), *effect_ptr,
+                                 *control_ptr);
+  input = BuildChangeInt32ToTagged(input);
+  Node* inputs[] = {jsgraph()->CEntryStubConstant(fun->result_size),  // C entry
+                    input, jsgraph()->Constant(module->instance->js_object),

[ahaas, 2016/06/14 13:03:13]

Use HeapConstant(module->instance->js_object) instead of
jsgraph()->Constant(module->instance->js_object) to avoid problems with parallel
compilation here.

[gdeepti, 2016/06/23 16:57:02]

Done.

+                    jsgraph()->ExternalConstant(
+                        ExternalReference(f, jsgraph()->isolate())),  // ref
+                    jsgraph()->Int32Constant(fun->nargs),             // arity
+                    jsgraph()->Constant(module->instance->context),   // context

[ahaas, 2016/06/14 13:03:13]

Use HeapConstant(module->instance->context) instead of
jsgraph()->Constant(module->instance->context) to avoid problems with parallel
compilation here.

[gdeepti, 2016/06/23 16:57:02]

Done.

+                    *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 = BuildChangeTaggedToFloat64(node);
+  node = graph()->NewNode(jsgraph()->machine()->ChangeFloat64ToInt32(), node);
+  return node;
+}
+
 Node* WasmGraphBuilder::BuildI32DivS(Node* left, Node* right,
                                      wasm::WasmCodePosition position) {
   MachineOperatorBuilder* m = jsgraph()->machine();
   trap_->ZeroCheck32(wasm::kTrapDivByZero, right, position);
   Node* before = *control_;
   Node* denom_is_m1;
   Node* denom_is_not_m1;
   Branch(
       graph()->NewNode(m->Word32Equal(), right, jsgraph()->Int32Constant(-1)),
       &denom_is_m1, &denom_is_not_m1);
@@ skipping 917 matching lines @@
     return jsgraph()->RelocatableIntPtrConstant(
         reinterpret_cast<uintptr_t>(module_->instance->mem_start + offset),
         RelocInfo::WASM_MEMORY_REFERENCE);
   }
 }
 
 Node* WasmGraphBuilder::MemSize(uint32_t offset) {
   DCHECK(module_ && module_->instance);
   uint32_t size = static_cast<uint32_t>(module_->instance->mem_size);
   if (offset == 0) {
-    if (!mem_size_) mem_size_ = jsgraph()->Int32Constant(size);
+    if (!mem_size_)
+      mem_size_ = jsgraph()->RelocatableInt32Constant(
+          size, RelocInfo::WASM_MEMORY_SIZE_REFERENCE);
     return mem_size_;
   } else {
-    return jsgraph()->Int32Constant(size + offset);
+    return jsgraph()->RelocatableInt32Constant(
+        size + offset, RelocInfo::WASM_MEMORY_SIZE_REFERENCE);
   }
 }
 
 Node* WasmGraphBuilder::FunctionTable() {
   DCHECK(module_ && module_->instance &&
          !module_->instance->function_table.is_null());
   if (!function_table_) {
     function_table_ = HeapConstant(module_->instance->function_table);
   }
   return function_table_;
@@ skipping 26 matching lines @@
   return node;
 }
 
 void WasmGraphBuilder::BoundsCheckMem(MachineType memtype, Node* index,
                                       uint32_t offset,
                                       wasm::WasmCodePosition position) {
   DCHECK(module_ && module_->instance);
   size_t size = module_->instance->mem_size;
   byte memsize = wasm::WasmOpcodes::MemSize(memtype);
 
+  // Check against the effective size.
+  size_t effective_size;
   if (offset >= size || (static_cast<uint64_t>(offset) + memsize) > size) {
-    // The access will always throw (unless memory is grown).
-    Node* cond = jsgraph()->Int32Constant(0);
-    trap_->AddTrapIfFalse(wasm::kTrapMemOutOfBounds, cond, position);
-    return;
+    effective_size = 0;
+  } else {
+    effective_size = size - offset - memsize + 1;
   }
-
-  // Check against the effective size.
-  size_t effective_size = size - offset - memsize;
   CHECK(effective_size <= kMaxUInt32);
 
   Uint32Matcher m(index);
   if (m.HasValue()) {
     uint32_t value = m.Value();
-    if (value <= effective_size) {
+    if (value < effective_size) {
       // The bounds check will always succeed.
       return;
     }
   }
 
-  Node* cond = graph()->NewNode(
-      jsgraph()->machine()->Uint32LessThanOrEqual(), index,
-      jsgraph()->Int32Constant(static_cast<uint32_t>(effective_size)));
+  Node* cond = graph()->NewNode(jsgraph()->machine()->Uint32LessThan(), index,
+                                jsgraph()->RelocatableInt32Constant(
+                                    static_cast<uint32_t>(effective_size),
+                                    RelocInfo::WASM_MEMORY_SIZE_REFERENCE));
 
   trap_->AddTrapIfFalse(wasm::kTrapMemOutOfBounds, cond, position);
 }
 
 MachineType WasmGraphBuilder::GetTypeForUnalignedAccess(uint32_t alignment,
                                                         bool signExtend) {
   switch (alignment) {
     case 0:
       return signExtend ? MachineType::Int8() : MachineType::Uint8();
     case 1:
@@ skipping 669 matching lines @@
                             function_->code_start_offset),
            compile_ms);
   }
 
   return code;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8