Removes open arrays (e.g. data[0]) from raw objects.

runtime/vm/raw_object.h

Index: runtime/vm/raw_object.h
===================================================================
--- runtime/vm/raw_object.h	(revision 37403)
+++ runtime/vm/raw_object.h	(working copy)
@@ -223,7 +223,6 @@
     SNAPSHOT_WRITER_SUPPORT()                                                  \
     HEAP_PROFILER_SUPPORT()                                                    \
 
-
 // RawObject is the base class of all raw objects, even though it carries the
 // class_ field not all raw objects are allocated in the heap and thus cannot
 // be dereferenced (e.g. RawSmi).
@@ -558,9 +557,13 @@
   RawSmi* length_;
 
   // Variable length data follows here.
-  RawAbstractType* types_[0];
+  RawAbstractType** types() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(RawAbstractType*)));
+    return reinterpret_cast<RawAbstractType**>(result);

[siva, 2014/06/17 22:29:50]

why not make a macro and use that everywhere?
e.g
#define OPEN_ARRAY_START(type)                                        \
  const uword result = reinterpret_cast<uword>(this) + sizeof(*this); \
  ASSERT(Utils::IsAligned(result, sizeof(type)));                     \
  return reinterpret_cast<type*>(result);                             \

and here:
RawAbstractType** type() { OPEN_ARRAY_START(RawAbstractType*); }

[zra, 2014/06/17 23:17:58]

Done.

+  }
   RawObject** to(intptr_t length) {
-    return reinterpret_cast<RawObject**>(&ptr()->types_[length - 1]);
+    return reinterpret_cast<RawObject**>(&ptr()->types()[length - 1]);
   }
 
   friend class SnapshotReader;
@@ -855,10 +858,12 @@
   intptr_t patch_code_pc_offset_;
   intptr_t lazy_deopt_pc_offset_;
 
-  intptr_t dummy_alignment_;
-
   // Variable length data follows here.
-  int32_t data_[0];
+  int32_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(int32_t)));
+    return reinterpret_cast<int32_t*>(result);
+  }

[siva, 2014/06/17 22:29:50]

int32_t* data() { OPEN_ARRAY_START(int32_t); }

[zra, 2014/06/17 23:17:57]

Done.

 
   friend class StackFrame;
   friend class MarkingVisitor;
@@ -880,7 +885,11 @@
   intptr_t size_;
 
   // Variable length data follows here.
-  uint8_t data_[0];
+  uint8_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint8_t)));
+    return reinterpret_cast<uint8_t*>(result);
+  }
 
   // Private helper function used while visiting stack frames. The
   // code which iterates over dart frames is also called during GC and
@@ -901,7 +910,11 @@
   intptr_t length_;  // Number of descriptors.
 
   // Variable length data follows here.
-  intptr_t data_[0];
+  intptr_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(intptr_t)));
+    return reinterpret_cast<intptr_t*>(result);
+  }
 
   friend class Object;
 };
@@ -925,7 +938,11 @@
   uword pc_;  // PC corresponding to this stack map representation.
 
   // Variable length data follows here (bitmap of the stack layout).
-  uint8_t data_[0];
+  uint8_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint8_t)));
+    return reinterpret_cast<uint8_t*>(result);
+  }
 };
 
 
@@ -952,7 +969,12 @@
   intptr_t length_;  // Number of descriptors.
   RawArray* names_;  // Array of [length_] variable names.
 
-  VarInfo data_[0];   // Variable info with [length_] entries.
+  // Variable info with [length_] entries.
+  VarInfo* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(intptr_t)));
+    return reinterpret_cast<VarInfo*>(result);
+  }
 };
 
 
@@ -966,6 +988,7 @@
     int8_t needs_stacktrace;   // True if a stacktrace is needed.
     int8_t has_catch_all;      // Catches all exceptions.
   };
+
  private:
   RAW_HEAP_OBJECT_IMPLEMENTATION(ExceptionHandlers);
 
@@ -977,7 +1000,11 @@
   RawArray* handled_types_data_;
 
   // Exception handler info of length [length_].
-  HandlerInfo data_[0];
+  HandlerInfo* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(intptr_t)));
+    return reinterpret_cast<HandlerInfo*>(result);
+  }
 };
 
 
@@ -989,7 +1016,11 @@
   RawSmi* length_;  // Number of deoptimization commands
 
   // Variable length data follows here.
-  intptr_t data_[0];
+  intptr_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(intptr_t)));
+    return reinterpret_cast<intptr_t*>(result);
+  }
 };
 
 
@@ -1003,9 +1034,13 @@
   RawContext* parent_;
 
   // Variable length data follows here.
-  RawInstance* data_[0];
+  RawInstance** data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(RawInstance*)));
+    return reinterpret_cast<RawInstance**>(result);
+  }
   RawObject** to(intptr_t num_vars) {
-    return reinterpret_cast<RawObject**>(&ptr()->data_[num_vars - 1]);
+    return reinterpret_cast<RawObject**>(&ptr()->data()[num_vars - 1]);
   }
 
   friend class SnapshotReader;
@@ -1033,11 +1068,17 @@
   intptr_t num_variables_;
 
   // Variable length data follows here.

[siva, 2014/06/17 22:29:50]

This comment should be above data() for consistency?

[zra, 2014/06/17 23:17:58]

Done.

-  RawObject** from() { return reinterpret_cast<RawObject**>(&ptr()->data_[0]); }
-  RawObject* data_[0];
+  RawObject** from() {
+    return reinterpret_cast<RawObject**>(&ptr()->data()[0]);
+  }
+  RawObject** data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(RawObject*)));
+    return reinterpret_cast<RawObject**>(result);
+  }
   RawObject** to(intptr_t num_vars) {
-    intptr_t data_length = num_vars * (sizeof(VariableDesc)/kWordSize);
-    return reinterpret_cast<RawObject**>(&ptr()->data_[data_length - 1]);
+    const intptr_t data_length = num_vars * (sizeof(VariableDesc)/kWordSize);
+    return reinterpret_cast<RawObject**>(&ptr()->data()[data_length - 1]);
   }
 };
 
@@ -1306,7 +1347,11 @@
 
   // A sequence of Chunks (typedef in Bignum) representing bignum digits.
   // Bignum::Chunk chunks_[Utils::Abs(signed_length_)];
-  uint8_t data_[0];
+  uint8_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint8_t)));
+    return reinterpret_cast<uint8_t*>(result);
+  }
 
   friend class SnapshotReader;
 };
@@ -1337,7 +1382,11 @@
   RAW_HEAP_OBJECT_IMPLEMENTATION(OneByteString);
 
   // Variable length data follows here.
-  uint8_t data_[0];
+  uint8_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint8_t)));
+    return reinterpret_cast<uint8_t*>(result);
+  }
 
   friend class ApiMessageReader;
   friend class SnapshotReader;
@@ -1348,7 +1397,11 @@
   RAW_HEAP_OBJECT_IMPLEMENTATION(TwoByteString);
 
   // Variable length data follows here.
-  uint16_t data_[0];
+  uint16_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint16_t)));
+    return reinterpret_cast<uint16_t*>(result);
+  }
 
   friend class SnapshotReader;
 };
@@ -1411,8 +1464,9 @@
   RawSmi* length_;
   // Variable length data follows here.
   RawObject** data() {
-    uword address_of_length = reinterpret_cast<uword>(&length_);
-    return reinterpret_cast<RawObject**>(address_of_length + kWordSize);
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(RawObject*)));
+    return reinterpret_cast<RawObject**>(result);
   }
   RawObject** to(intptr_t length) {
     return reinterpret_cast<RawObject**>(&ptr()->data()[length - 1]);
@@ -1510,11 +1564,14 @@
  protected:
   RawObject** from() { return reinterpret_cast<RawObject**>(&ptr()->length_); }
   RawSmi* length_;
+  // Variable length data follows here.
+  uint8_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint8_t)));
+    return reinterpret_cast<uint8_t*>(result);
+  }
   RawObject** to() { return reinterpret_cast<RawObject**>(&ptr()->length_); }
 
-  // Variable length data follows here.
-  uint8_t data_[0];
-
   friend class Api;
   friend class Object;
   friend class Instance;
@@ -1604,7 +1661,11 @@
   intptr_t flags_;  // Represents global/local, case insensitive, multiline.
 
   // Variable length data follows here.
-  uint8_t data_[0];
+  uint8_t* data() {
+    const uword result = reinterpret_cast<uword>(this) + sizeof(*this);
+    ASSERT(Utils::IsAligned(result, sizeof(uint8_t)));
+    return reinterpret_cast<uint8_t*>(result);
+  }
 };