[wasm] Disassemble wasm code from script

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index fac56495a0048ab66f4678fad43bce600df9050f..1ef946e5b0da97105895a70356b3aa32bc4caf7d 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -78,25 +78,35 @@ int PropertyDetails::field_width_in_words() const {
   int holder::name() const { return READ_INT_FIELD(this, offset); }           \
   void holder::set_##name(int value) { WRITE_INT_FIELD(this, offset, value); }
 
-
-#define ACCESSORS(holder, name, type, offset)                                 \
-  type* holder::name() const { return type::cast(READ_FIELD(this, offset)); } \
-  void holder::set_##name(type* value, WriteBarrierMode mode) {               \
-    WRITE_FIELD(this, offset, value);                                         \
-    CONDITIONAL_WRITE_BARRIER(GetHeap(), this, offset, value, mode);          \
+#define ACCESSORS_CHECKED(holder, name, type, offset, condition)     \
+  type* holder::name() const {                                       \
+    DCHECK(condition);                                               \
+    return type::cast(READ_FIELD(this, offset));                     \
+  }                                                                  \
+  void holder::set_##name(type* value, WriteBarrierMode mode) {      \
+    DCHECK(condition);                                               \
+    WRITE_FIELD(this, offset, value);                                \
+    CONDITIONAL_WRITE_BARRIER(GetHeap(), this, offset, value, mode); \
   }
 
+#define ACCESSORS(holder, name, type, offset) \
+  ACCESSORS_CHECKED(holder, name, type, offset, true)
 
 // Getter that returns a Smi as an int and writes an int as a Smi.
-#define SMI_ACCESSORS(holder, name, offset)             \
-  int holder::name() const {                            \
-    Object* value = READ_FIELD(this, offset);           \
-    return Smi::cast(value)->value();                   \
-  }                                                     \
-  void holder::set_##name(int value) {                  \
-    WRITE_FIELD(this, offset, Smi::FromInt(value));     \
+#define SMI_ACCESSORS_CHECKED(holder, name, offset, condition) \
+  int holder::name() const {                                   \
+    DCHECK(condition);                                         \
+    Object* value = READ_FIELD(this, offset);                  \
+    return Smi::cast(value)->value();                          \
+  }                                                            \
+  void holder::set_##name(int value) {                         \
+    DCHECK(condition);                                         \
+    WRITE_FIELD(this, offset, Smi::FromInt(value));            \
   }
 
+#define SMI_ACCESSORS(holder, name, offset) \
+  SMI_ACCESSORS_CHECKED(holder, name, offset, true)
+
 #define SYNCHRONIZED_SMI_ACCESSORS(holder, name, offset)    \
   int holder::synchronized_##name() const {                 \
     Object* value = ACQUIRE_READ_FIELD(this, offset);       \
@@ -5567,12 +5577,18 @@ ACCESSORS(Script, context_data, Object, kContextOffset)
 ACCESSORS(Script, wrapper, HeapObject, kWrapperOffset)
 SMI_ACCESSORS(Script, type, kTypeOffset)
 ACCESSORS(Script, line_ends, Object, kLineEndsOffset)
-ACCESSORS(Script, eval_from_shared, Object, kEvalFromSharedOffset)
-SMI_ACCESSORS(Script, eval_from_position, kEvalFromPositionOffset)
+ACCESSORS_CHECKED(Script, eval_from_shared, Object, kEvalFromSharedOffset,

[Yang, 2016/06/16 13:49:35]

I have plans to move the EvalFromShared and EvalFromPosition fields into a
separate FixedArray (because I need to add yet another field for eval scripts).
Could you do the same? We would replace these two fields by a TypeSpecificData
field.

[Clemens Hammacher, 2016/06/17 18:01:55]

Sure, that change would be compatible with wasm. All we need is getting the wasm
object and the function index from the script.

+                  this->type() != TYPE_WASM)
+SMI_ACCESSORS_CHECKED(Script, eval_from_position, kEvalFromPositionOffset,
+                      this->type() != TYPE_WASM)
 ACCESSORS(Script, shared_function_infos, Object, kSharedFunctionInfosOffset)
 SMI_ACCESSORS(Script, flags, kFlagsOffset)
 ACCESSORS(Script, source_url, Object, kSourceUrlOffset)
 ACCESSORS(Script, source_mapping_url, Object, kSourceMappingUrlOffset)
+ACCESSORS_CHECKED(Script, wasm_object, JSObject, kEvalFromSharedOffset,
+                  this->type() == TYPE_WASM)
+SMI_ACCESSORS_CHECKED(Script, wasm_function_index, kEvalFromPositionOffset,
+                      this->type() == TYPE_WASM)
 
 Script::CompilationType Script::compilation_type() {
   return BooleanBit::get(flags(), kCompilationTypeBit) ?