[wasm] Distinguish Liftoff code from Turbofan code

For memory tracing, output a 'T' for Turbofan code and an 'L' for
Liftoff code. To do this, the WasmCodeWrapper now has some dispatch
functions which work for both on-the-heap and off-the-heap code.
We can probably refactor more code by having this mechanism.

Since the output of --wasm-trace-memory differs now between Turbofan
and Liftoff, the message test is split in two.

R=titzer@chromium.org
CC=mstarzinger@chromium.org

Bug: v8:6600
Change-Id: Ic5fd18c631f5c8aaad19d639df75b18098895b5a
Reviewed-on: https://chromium-review.googlesource.com/868214
Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50655}

src/frames.cc

@@ -1727,6 +1727,13 @@ Address WasmCompiledFrame::GetCallerStackPointer() const {
   return fp() + ExitFrameConstants::kCallerSPOffset;
 }
 
+WasmCodeWrapper WasmCompiledFrame::wasm_code() const {
+  return FLAG_wasm_jit_to_native
+             ? WasmCodeWrapper(
+                   isolate()->wasm_engine()->code_manager()->LookupCode(pc()))
+             : WasmCodeWrapper(Handle<Code>(LookupCode(), isolate()));
+}
+
 WasmInstanceObject* WasmCompiledFrame::wasm_instance() const {
   WasmInstanceObject* obj =
       FLAG_wasm_jit_to_native
@@ -1752,26 +1759,9 @@ int WasmCompiledFrame::position() const {
 
 void WasmCompiledFrame::Summarize(std::vector<FrameSummary>* functions) const {
   DCHECK(functions->empty());
-  WasmCodeWrapper code;
-  Handle<WasmInstanceObject> instance;
-  int offset = -1;
-  if (FLAG_wasm_jit_to_native) {
-    code = WasmCodeWrapper(
-        isolate()->wasm_engine()->code_manager()->LookupCode(pc()));
-    offset =
-        static_cast<int>(pc() - code.GetWasmCode()->instructions().start());
-    instance = Handle<WasmInstanceObject>(
-        WasmInstanceObject::cast(code.GetWasmCode()
-                                     ->owner()
-                                     ->compiled_module()
-                                     ->weak_owning_instance()
-                                     ->value()),
-        isolate());
-  } else {
-    code = WasmCodeWrapper(Handle<Code>(LookupCode(), isolate()));
-    offset = static_cast<int>(pc() - code.GetCode()->instruction_start());
-    instance = Handle<WasmInstanceObject>(wasm_instance(), isolate());
-  }
+  WasmCodeWrapper code = wasm_code();
+  int offset = static_cast<int>(pc() - code.instructions().start());
+  Handle<WasmInstanceObject> instance = code.wasm_instance();
   FrameSummary::WasmCompiledFrameSummary summary(
       isolate(), instance, code, offset, at_to_number_conversion());
   functions->push_back(summary);

src/frames.h

@@ -968,6 +968,7 @@ class WasmCompiledFrame final : public StandardFrame {
 
   // Accessors.
   WasmInstanceObject* wasm_instance() const;
+  WasmCodeWrapper wasm_code() const;
   uint32_t function_index() const;
   Script* script() const override;
   int position() const override;

src/runtime/runtime-test.cc

@@ -1126,9 +1126,11 @@ RUNTIME_FUNCTION(Runtime_WasmTraceMemory) {
   // TODO(titzer): eliminate dependency on WasmModule definition here.
   int func_start =
       frame->wasm_instance()->module()->functions[func_index].code.offset();
-  // TODO(clemensh): Determine compiler (TurboFan / Liftoff).
-  wasm::TraceMemoryOperation(wasm::ExecutionEngine::kTurbofan, info, func_index,
-                             pos - func_start, mem_start);
+  wasm::ExecutionEngine eng = frame->wasm_code().is_liftoff()
+                                  ? wasm::ExecutionEngine::kLiftoff
+                                  : wasm::ExecutionEngine::kTurbofan;
+  wasm::TraceMemoryOperation(eng, info, func_index, pos - func_start,
+                             mem_start);
   return isolate->heap()->undefined_value();
 }
 

src/wasm/wasm-code-wrapper.cc

@@ -4,9 +4,10 @@
 
 #include "src/wasm/wasm-code-wrapper.h"
 
-#include "src/objects.h"
+#include "src/objects-inl.h"
 #include "src/objects/code.h"
 #include "src/wasm/wasm-code-manager.h"
+#include "src/wasm/wasm-objects.h"
 
 namespace v8 {
 namespace internal {
@@ -46,5 +47,23 @@ void WasmCodeWrapper::Disassemble(const char* name, Isolate* isolate,
 }
 #endif
 
+bool WasmCodeWrapper::is_liftoff() const {
+  return IsCodeObject() ? !GetCode()->is_turbofanned()
+                        : GetWasmCode()->is_liftoff();
+}
+
+Vector<uint8_t> WasmCodeWrapper::instructions() const {
+  if (!IsCodeObject()) return GetWasmCode()->instructions();
+  Handle<Code> code = GetCode();
+  return {code->instruction_start(),
+          static_cast<size_t>(code->instruction_size())};
+}
+
+Handle<WasmInstanceObject> WasmCodeWrapper::wasm_instance() const {
+  return IsCodeObject()
+             ? handle(WasmInstanceObject::GetOwningInstanceGC(*GetCode()))
+             : handle(WasmInstanceObject::GetOwningInstance(GetWasmCode()));
+}
+
 }  // namespace internal
 }  // namespace v8

src/wasm/wasm-code-wrapper.h

@@ -13,6 +13,7 @@ class WasmCode;
 }  // namespace wasm
 
 class Code;
+class WasmInstanceObject;
 
 // TODO(mtrofin): remove once we remove FLAG_wasm_jit_to_native
 class WasmCodeWrapper {
@@ -25,6 +26,11 @@ class WasmCodeWrapper {
   const wasm::WasmCode* GetWasmCode() const;
   bool is_null() const { return code_ptr_.wasm_code_ == nullptr; }
   bool IsCodeObject() const;
+  bool is_liftoff() const;
+
+  Vector<uint8_t> instructions() const;
+
+  Handle<WasmInstanceObject> wasm_instance() const;
 
 #ifdef ENABLE_DISASSEMBLER
   void Disassemble(const char* name, Isolate* isolate, std::ostream& os) const;

test/message/message.status

@@ -36,4 +36,11 @@
   # tested standalone.
   'fail/modules-skip*': [SKIP],
 }],  # ALWAYS
+
+# Liftoff is currently only sufficiently implemented on x64 and ia32.
+# TODO(clemensh): Implement on all other platforms (crbug.com/v8/6600).
+['arch != x64 and arch != ia32', {
+  'wasm-trace-memory-liftoff': [SKIP],
+}], # arch != x64 and arch != ia32
+
 ]

test/message/wasm-trace-memory-liftoff.js

@@ -0,0 +1,7 @@
+// Copyright 2017 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.
+
+// Flags: --no-stress-opt --expose-wasm --wasm-trace-memory --liftoff
+
+load("test/message/wasm-trace-memory.js");

test/message/wasm-trace-memory-liftoff.out

@@ -0,0 +1,9 @@
+L        0+0x3      load  @00000004 i32:0 / 00000000
+L        1+0x3      load  @00000001  i8:0 / 00
+L        3+0x5      store @00000004 i32:305419896 / 12345678
+L        0+0x3      load  @00000002 i32:1450704896 / 56780000
+L        1+0x3      load  @00000006  i8:52 / 34
+L        2+0x3      load  @00000002 f32:68169720922112.000000 / 56780000
+L        4+0x5      store @00000004  i8:171 / ab
+L        0+0x3      load  @00000002 i32:1454047232 / 56ab0000
+L        2+0x3      load  @00000002 f32:94008244174848.000000 / 56ab0000

test/message/wasm-trace-memory.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --no-stress-opt --expose-wasm --wasm-trace-memory
+// Flags: --no-stress-opt --expose-wasm --wasm-trace-memory --no-liftoff
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");